Causes & Symptoms of Diseases
What Causes Whipple’s Disease?
Bacteria called Tropheryma whipplei (T. whipplei) cause Whipple’s disease. T. whipplei infection can cause internal sores, also called lesions, and the thickening of tissues. Villi, which are tiny fingerlike projections that line the small intestine, take on an abnormal, club like appearance. The damaged intestinal lining fails to properly absorb nutrients, causing diarrhea and malnutrition.
Scientists are unsure how T. whipplei infects people. One theory is that some people are more vulnerable to Whipple’s disease—probably due to genetic factors that influence the body’s immune system. This theory is supported by the existence of a relatively high number of asymptomatic carriers—people who have the bacteria in their bodies but don’t get sick. Also, the bacteria are more common in the environment—showing up in soil and sewage wastewater—than would be predicted based on the rareness of the disease. And while multiple cases of Whipple’s disease have occurred within the same family, no documentation exists of a person-to-person transmission.
What are the Signs and Symptoms of Whipple’s Disease?
Signs and symptoms of Whipple’s disease vary widely.
Classic signs and symptoms of Whipple’s disease include
- periodic joint pain, with or without inflammation, that may persist for years before the appearance of other symptoms
- chronic diarrhea, with or without blood
- weight loss
- abdominal pain and bloating
- anemia—a condition in which the blood has a lower-than-normal number of red blood cells
Less common signs and symptoms of Whipple’s disease include
- darkening of the skin
- enlarged lymph nodes
- chronic cough
- chest pain
- pericarditis—inflammation of the membrane surrounding the heart
- heart failure
Neurologic symptoms occur in some people diagnosed with Whipple’s disease and can mimic symptoms of almost any other neurologic condition.
Neurologic symptoms of Whipple’s disease include
- vision problems
- facial numbness
- muscle weakness or twitching
- difficulty walking
- memory problems
Symptoms of neurologic, lung, or heart disease occasionally appear without gastrointestinal symptoms.
What Causes Wilson Disease?
Wilson disease is caused by a buildup of copper in the body. Normally, copper from the diet is filtered out by the liver and released into bile, which flows out of the body through the gastrointestinal tract. People who have Wilson disease cannot release copper from the liver at a normal rate, due to a mutation of the ATP7B gene. When the copper storage capacity of the liver is exceeded, copper is released into the bloodstream and travels to other organs—including the brain, kidneys, and eyes.
What are the Symptoms of Wilson Disease?
Wilson disease first attacks the liver, the central nervous system, or both.
A buildup of copper in the liver may cause ongoing liver disease. Rarely, acute liver failure occurs; most patients develop signs and symptoms that accompany chronic liver disease, including
- swelling of the liver or spleen
- jaundice, or yellowing of the skin and whites of the eyes
- fluid buildup in the legs or abdomen
- a tendency to bruise easily
A buildup of copper in the central nervous system may result in neurologic symptoms, including
- problems with speech, swallowing, or physical coordination
- tremors or uncontrolled movements
- muscle stiffness
- behavioral changes
Other signs and symptoms of Wilson disease include
- low platelet or white blood cell count
- slower blood clotting, measured by a blood test
- high levels of amino acids, protein, uric acid, and carbohydrates in urine
- premature osteoporosis and arthritis
Kayser-Fleischer rings result from a buildup of copper in the eyes and are the most unique sign of Wilson disease. They appear in each eye as a rusty-brown ring around the edge of the iris and in the rim of the cornea. The iris is the colored part of the eye surrounding the pupil. The cornea is the transparent outer membrane that covers the eye.
Causes of NASH Disease
Although NASH has become more common, its underlying cause is still not clear. It most often occurs in persons who are middle-aged and overweight or obese. Many patients with NASH have elevated blood lipids, such as cholesterol and triglycerides, and many have diabetes or pre-diabetes, but not every obese person or every patient with diabetes has NASH. Furthermore, some patients with NASH are not obese, do not have diabetes, and have normal blood cholesterol and lipids. NASH can occur without any apparent risk factor and can even occur in children. Thus, NASH is not simply obesity that affects the liver.
While the underlying reason for the liver injury that causes NASH is not known, several factors are possible candidates:
- insulin resistance
- release of toxic inflammatory proteins by fat cells (cytokines)
- oxidative stress (deterioration of cells) inside liver cells
Symptoms of Nash Disease
NASH is usually a silent disease with few or no symptoms. Patients generally feel well in the early stages and only begin to have symptoms—such as fatigue, weight loss, and weakness—once the disease is more advanced or cirrhosis develops. The progression of NASH can take years, even decades. The process can stop and, in some cases, reverse on its own without specific therapy. Or NASH can slowly worsen, causing scarring or “fibrosis” to appear and accumulate in the liver. As fibrosis worsens, cirrhosis develops; the liver becomes seriously scarred, hardened, and unable to function normally. Not every person with NASH develops cirrhosis, but once serious scarring or cirrhosis is present, few treatments can halt the progression. A person with cirrhosis experiences fluid retention, muscle wasting, bleeding from the intestines, and liver failure. Liver transplantation is the only treatment for advanced cirrhosis with liver failure, and transplantation is increasingly performed in people with NASH. NASH ranks as one of the major causes of cirrhosis in America, behind hepatitis C and alcoholic liver disease.
What Causes Crohn’s Disease?
Several theories exist about what causes Crohn’s disease, but none have been proven. The human immune system is made from cells and different proteins that protect people from infection. The most popular theory is that the body’s immune system reacts abnormally in people with Crohn’s disease, mistaking bacteria, foods, and other substances for being foreign. The immune system’s response is to attack these “invaders.” During this process, white blood cells accumulate in the lining of the intestines, producing chronic inflammation, which leads to ulcerations and bowel injury.
Scientists do not know if the abnormality in the functioning of the immune system in people with Crohn’s disease is a cause, or a result, of the disease. Research shows that the inflammation seen in the GI tract of people with Crohn’s disease involves several factors: the genes the patient has inherited, the immune system itself, and the environment. Foreign substances, also referred to as antigens, are found in the environment. One possible cause for inflammation may be the body’s reaction to these antigens, or that the antigens themselves are the cause for the inflammation. Scientists have found that high levels of a protein produced by the immune system, called tumor necrosis factor (TNF), are present in people with Crohn’s disease.
What are the Symptoms of Crohn's Disease?
The most common symptoms of Crohn’s disease are abdominal pain, often in the lower right area, and diarrhea. Rectal bleeding, weight loss, arthritis, skin problems, and fever may also occur. Bleeding may be serious and persistent, leading to anemia. Children with Crohn’s disease may suffer delayed development and stunted growth. The range and severity of symptoms varies.
What Causes GERD?
The reason some people develop GERD is still unclear. However, research shows that in people with GERD, the LES relaxes while the rest of the esophagus is working. Anatomical abnormalities such as a hiatal hernia may also contribute to GERD. A hiatal hernia occurs when the upper part of the stomach and the LES move above the diaphragm, the muscle wall that separates the stomach from the chest. Normally, the diaphragm helps the LES keep acid from rising up into the esophagus. When a hiatal hernia is present, acid reflux can occur more easily. A hiatal hernia can occur in people of any age and is most often a normal finding in otherwise healthy people over age 50. Most of the time, a hiatal hernia produces no symptoms.
Other factors that may contribute to GERD include:
Common foods that can worsen reflux symptoms:
- citrus fruits
- drinks with caffeine or alcohol
- fatty and fried foods
- garlic and onions
- mint flavorings
- spicy foods
- tomato-based foods, like spaghetti sauce, salsa, chili, and pizza
What are the Symptoms of GERD?
The main symptom of GERD in adults is frequent heartburn, also called acid indigestion—burning-type pain in the lower part of the mid-chest, behind the breast bone, and in the mid-abdomen. Most children under 12 years with GERD, and some adults, have GERD without heartburn. Instead, they may experience a dry cough, asthma symptoms, or trouble swallowing.
What Causes Sickle Cell Anemia?
Sickle cell anemia is an inherited disease. People who have the disease inherit two copies of the sickle cell gene—one from each parent.
The sickle cell gene causes the body to make abnormal hemoglobin. Hemoglobin is an iron-rich protein in red blood cells. It carries oxygen from the lungs to the rest of the body.
In sickle cell anemia, the hemoglobin sticks together after it delivers oxygen to the body's tissues. These clumps of hemoglobin are like liquid fibers. They cause the red blood cells to become stiff and have a sickle, or crescent, shape.
Sickle cells tend to stick together or to blood vessel walls, causing them to get caught in the blood vessels. (Other cells also may play a role in this process.)
Two copies of the sickle cell gene are needed for the body to make the abnormal hemoglobin found in sickle cell anemia.
Sickle Cell Trait
If you inherit one copy of the sickle cell gene (from one parent), you won't have sickle cell anemia. Instead, you'll have sickle cell trait.
People who have sickle cell trait usually have no symptoms and lead normal lives. However, some people may have medical complications.
People who have sickle cell trait also can pass the sickle cell gene to their children. The following image shows how two parents who have sickle cell trait can pass the sickle cell gene to their children.
When both parents have a normal gene and an abnormal gene, each child has a 25 percent chance of inheriting two normal genes; a 50 percent chance of inheriting one normal gene and one abnormal gene; and a 25 percent chance of inheriting two abnormal genes.
What Are the Signs and Symptoms of Sickle Cell Anemia?
The signs and symptoms of sickle cell anemia vary. Some people have mild symptoms. Others have very severe symptoms and often are hospitalized for treatment.
Sickle cell anemia is present at birth, but many infants don't show any signs until after 4 months of age.
The most common signs and symptoms are linked to anemia and pain. Other signs and symptoms are linked to the disease's complications.
Signs and Symptoms Related to Anemia
The most common symptom of anemia is fatigue (feeling tired or weak). Other signs and symptoms of anemia may include:
- Shortness of breath
- Coldness in the hands and feet
- Paler than normal skin or mucous membranes (the tissue that lines your nose, mouth, and other organs and body cavities)
Signs and Symptoms Related to Pain
Sudden pain throughout the body is a common symptom of sickle cell anemia. This pain is called a sickle cell crisis. Sickle cell crises often affect the bones, lungs, abdomen, and joints.
These crises occur when sickled red blood cells form clumps in the bloodstream. (Other cells also may play a role in this clumping process.) These clumps of cells stick to small blood vessels and block blood flow to the limbs and organs. This can cause pain and organ damage.
The pain from sickle cell anemia can be acute or chronic, but acute pain is more common. Acute pain is sudden and can range from mild to very severe. The pain usually lasts from hours to as long as a week or more.
Chronic pain often lasts for weeks or months. Chronic pain can be hard to bear and mentally draining. This pain may limit your daily activities.
Almost all people who have sickle cell anemia have painful crises at some point in their lives. Some have these crises less than once a year. Others may have crises once a month or more.
Many factors can play a role in sickle cell crises. Often, more than one factor is involved and the exact cause isn't known.
You can control some factors. For example, the risk of a sickle cell crisis increases if you're dehydrated (your body doesn't have enough fluids). Drinking plenty of fluids can lower the risk of a painful crisis.
You can't control other factors, such as infections.
Painful crises are the leading cause of emergency room visits and hospital stays for people who have sickle cell anemia.
Complications of Sickle Cell Anemia
Sickle cell crises can affect many parts of the body and cause many complications.
Sickle cells can block the small blood vessels in the hands and feet in children (usually those younger than 4 years of age). This condition is called hand-foot syndrome. It can lead to pain, swelling, and fever.
Swelling often occurs on the back of the hands and feet and moves into the fingers and toes. One or both hands and/or feet may be affected at the same time.
The spleen is an organ in the abdomen. Normally, it filters out abnormal red blood cells and helps fight infections. In some cases, the spleen may trap red blood cells that should be in the bloodstream. This causes the spleen to grow large and leads to anemia.
If the spleen traps too many red blood cells, you may need blood transfusions until your body can make more cells and recover.
Both children and adults who have sickle cell anemia may have a hard time fighting infections. This is because sickle cell anemia can damage the spleen, an organ that helps fight infections.
Infants and young children who have damaged spleens are more likely to get serious infections that can kill them within hours or days. Bloodstream infections are the most common cause of death in young children who have sickle cell anemia.
Medicines and vaccines can help prevent severe illness and death. For example, vaccines are available for infections such as meningitis, influenza, and hepatitis.
Getting treatment right away for high fevers (which can be a sign of a severe infection) also helps prevent death in infants and children who have sickle cell anemia.
Acute Chest Syndrome
Acute chest syndrome is a life-threatening condition linked to sickle cell anemia. This syndrome is similar to pneumonia. An infection or sickle cells trapped in the lungs cause acute chest syndrome.
People who have this condition often have chest pain, shortness of breath, and fever. They also often have low oxygen levels and abnormal chest x ray results.
Damage to the small blood vessels in the lungs makes it hard for the heart to pump blood through the lungs. This causes blood pressure in the lungs to rise.
Increased blood pressure in the lungs is called pulmonary hypertension (PH). Shortness of breath and fatigue are the main symptoms of PH.
Delayed Growth and Puberty in Children
Children who have sickle cell anemia often grow more slowly than other children. They may reach puberty later. A shortage of red blood cells causes the slow growth rate. Adults who have sickle cell anemia often are slender or smaller in size than other adults.
Two forms of stroke can occur in people who have sickle cell anemia. One form occurs if a blood vessel in the brain is damaged and blocked. This type of stroke occurs more often in children than adults. The other form of stroke occurs if a blood vessel in the brain bursts.
Either type of stroke can cause learning problems and/or lasting brain damage, long-term disability, paralysis (an inability to move), or death.
Sickle cells also can affect the small blood vessels that deliver oxygen-rich blood to the eyes. Sickle cells can block these vessels or cause them to break open and bleed. This can damage the retinas—thin layers of tissue at the back of the eyes. The retinas take the images you see and send them to your brain.
This damage can cause serious problems, including blindness.
Males who have sickle cell anemia may have painful, unwanted erections. This condition is called priapism (PRI-a-pizm). It happens because the sickle cells block blood flow out of an erect penis. Over time, priapism can damage the penis and lead to impotence.
When red blood cells die, they release their hemoglobin. The body breaks down this protein into a compound called bilirubin. Too much bilirubin in the body can cause stones to form in the gallbladder, called gallstones.
Gallstones may cause steady pain that lasts for 30 minutes or more in the upper right side of the belly, under the right shoulder, or between the shoulder blades. The pain may happen after eating fatty meals.
People who have gallstones may have nausea (feeling sick to the stomach), vomiting, fever, sweating, chills, clay-colored stools, or jaundice (a yellowish color of the skin or whites of the eyes).
Ulcers on the Legs
Sickle cell ulcers (sores) usually begin as small, raised, crusted sores on the lower third of the leg. Leg sores may occur more often in males than in females. These sores usually develop in people who are aged 10 years or older.
The cause of sickle cell ulcers isn't clear. The number of ulcers can vary from one to many. Some heal quickly, but others persist for years or come back after healing.
Multiple Organ Failure
Multiple organ failure is rare, but serious. It happens if you have a sickle cell crisis that causes two out of three major organs (lungs, liver, or kidneys) to fail. Often, multiple organ failure occurs during an unusually severe pain crisis.
Symptoms of this complication are fever, rapid heartbeat, problems breathing, and changes in mental status (such as sudden tiredness or confusion).
Alzheimer’s disease is an irreversible, progressive brain disease that slowly destroys memory and thinking skills, and eventually even the ability to carry out the simplest tasks. In most people with Alzheimer’s, symptoms first appear after age 60.
Alzheimer’s disease is the most common cause of dementia among older people. Dementia is the loss of cognitive functioning—thinking, remembering, and reasoning—to such an extent that it interferes with a person’s daily life and activities. Estimates vary, but experts suggest that as many as 5.1 million Americans may have Alzheimer’s.
Alzheimer’s disease is named after Dr. Alois Alzheimer. In 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behavior. After she died, he examined her brain and found many abnormal clumps (now called amyloid plaques) and tangled bundles of fibers (now called neurofibrillary tangles). Plaques and tangles in the brain are two of the main features of Alzheimer’s disease. The third is the loss of connections between nerve cells (neurons) in the brain.
Changes in the Brain in Alzheimer’s Disease
Although we still don’t know what starts the Alzheimer’s disease process, we do know that damage to the brain begins as many as 10 to 20 years before any problems are evident. Tangles begin to develop deep in the brain, in an area called the entorhinal cortex, and plaques form in other areas. As more and more plaques and tangles form in particular brain areas, healthy neurons begin to work less efficiently. Then, they lose their ability to function and communicate with each other, and eventually they die. This damaging process spreads to a nearby structure, called the hippocampus, which is essential in forming memories. As the death of neurons increases, affected brain regions begin to shrink. By the final stage of Alzheimer’s, damage is widespread and brain tissue has shrunk significantly.
Very Early Signs and Symptoms of Alzheimer’s Disease
Memory problems are one of the first signs of Alzheimer’s disease. Some people with memory problems have a condition called amnestic mild cognitive impairment (MCI). People with this condition have more memory problems than normal for people their age, but their symptoms are not as severe as those with Alzheimer’s. More people with MCI, compared with those without MCI, go on to develop Alzheimer’s.
Other changes may also signal the very early stages of Alzheimer’s disease. For example, brain imaging and biomarker studies of people with MCI and those with a family history of Alzheimer’s are beginning to detect early changes in the brain like those seen in Alzheimer’s. These findings will need to be confirmed by other studies but appear promising. Other recent research has found links between some movement difficulties and MCI. Researchers also have seen links between some problems with the sense of smell and cognitive problems. Such findings offer hope that some day we may have tools that could help detect Alzheimer’s early, track the course of the disease, and monitor response to treatments.
Mild Alzheimer’s Disease
As Alzheimer’s disease progresses, memory loss continues and changes in other cognitive abilities appear. Problems can include getting lost, trouble handling money and paying bills, repeating questions, taking longer to complete normal daily tasks, poor judgment, and small mood and personality changes. People often are diagnosed in this stage.
Moderate Alzheimer’s Disease
In this stage, damage occurs in areas of the brain that control language, reasoning, sensory processing, and conscious thought. Memory loss and confusion increase, and people begin to have problems recognizing family and friends. They may be unable to learn new things, carry out tasks that involve multiple steps (such as getting dressed), or cope with new situations. They may have hallucinations, delusions, and paranoia, and may behave impulsively.
Severe Alzheimer’s Disease
By the final stage, plaques and tangles have spread throughout the brain and brain tissue has shrunk significantly. People with severe Alzheimer’s cannot communicate and are completely dependent on others for their care. Near the end, the person may be in bed most or all of the time as the body shuts down.
What Causes Alzheimer’s
Scientists don’t yet fully understand what causes Alzheimer’s disease, but it is clear that it develops because of a complex series of events that take place in the brain over a long period of time. It is likely that the causes include genetic, environmental, and lifestyle factors. Because people differ in their genetic make-up and lifestyle, the importance of these factors for preventing or delaying Alzheimer’s differs from person to person.
The Basics of Alzheimer’s
Scientists are conducting studies to learn more about plaques, tangles, and other features of Alzheimer’s disease. They can now visualize plaques by imaging the brains of living individuals. They are also exploring the very earliest steps in the disease process. Findings from these studies will help them understand the causes of Alzheimer’s.
One of the great mysteries of Alzheimer’s disease is why it largely strikes older adults. Research on how the brain changes normally with age is shedding light on this question. For example, scientists are learning how age-related changes in the brain may harm neurons and contribute to Alzheimer’s damage. These age-related changes include atrophy (shrinking) of certain parts of the brain, inflammation, and the production of unstable molecules called free radicals.
In a very few families, people develop Alzheimer’s disease in their 30s, 40s, and 50s. Many of these people have a mutation, or permanent change, in one of three genes that they inherited from a parent. We know that these gene mutations cause Alzheimer’s in these “early-onset” familial cases. Not all early-onset cases are caused by such mutations.
Most people with Alzheimer’s disease have “late-onset” Alzheimer’s, which usually develops after age 60. Many studies have linked a gene called APOE to late-onset Alzheimer’s. This gene has several forms. One of them, APOE ε4, increases a person’s risk of getting the disease. About 40 percent of all people who develop late-onset Alzheimer’s carry this gene. However, carrying the APOE ε4 form of the gene does not necessarily mean that a person will develop Alzheimer’s disease, and people carrying no APOE ε4 forms can also develop the disease.
Most experts believe that additional genes may influence the development of late-onset Alzheimer’s in some way. Scientists around the world are searching for these genes. Researchers have identified variants of the SORL1, CLU, PICALM, and CR1 genes that may play a role in risk of late-onset Alzheimer’s.
A nutritious diet, physical activity, social engagement, and mentally stimulating pursuits can all help people stay healthy. New research suggests the possibility that these factors also might help to reduce the risk of cognitive decline and Alzheimer’s disease. Scientists are investigating associations between cognitive decline and vascular and metabolic conditions such as heart disease, stroke, high blood pressure, diabetes, and obesity. Understanding these relationships and testing them in clinical trials will help us understand whether reducing risk factors for these diseases may help with Alzheimer’s as well.
How Alzheimer’s Disease Is Diagnosed
Alzheimer’s disease can be definitively diagnosed only after death by linking clinical course with an examination of brain tissue and pathology in an autopsy. But doctors now have several methods and tools to help them determine fairly accurately whether a person who is having memory problems has “possible Alzheimer’s disease” (dementia may be due to another cause) or “probable Alzheimer’s disease” (no other cause for dementia can be found). To diagnose Alzheimer’s, doctors:
- ask questions about the person’s overall health, past medical problems, ability to carry out daily activities, and changes in behavior and personality
- conduct tests of memory, problem solving, attention, counting, and language
- carry out medical tests, such as tests of blood, urine, or spinal fluid
- perform brain scans, such as computerized tomography (CT) or magnetic resonance imaging (MRI)
These tests may be repeated to give doctors information about how the person’s memory is changing over time.
Early diagnosis is beneficial for several reasons. Having an early diagnosis and starting treatment in the early stages of the disease can help preserve function for months to years, even though the underlying disease process cannot be changed. Having an early diagnosis also helps families plan for the future, make living arrangements, take care of financial and legal matters, and develop support networks.
In addition, an early diagnosis can provide greater opportunities for people to get involved in clinical trials. In a clinical trial, scientists test drugs or treatments to see which are most effective and for whom they work best.
How Alzheimer’s Is Treated
Alzheimer’s disease is a complex disease, and no single “magic bullet” is likely to prevent or cure it. That’s why current treatments focus on several different aspects, including helping people maintain mental function; managing behavioral symptoms; and slowing, delaying, or preventing the disease.
Helping People with Alzheimer’s Maintain Mental Function
Four medications are approved by the U.S. Food and Drug Administration to treat Alzheimer’s. Donepezil (Aricept®), rivastigmine (Exelon®), and galantamine (Razadyne®) are used to treat mild to moderate Alzheimer’s (donepezil can be used for severe Alzheimer’s as well). Memantine (Namenda®) is used to treat moderate to severe Alzheimer’s. These drugs work by regulating neurotransmitters (the chemicals that transmit messages between neurons). They may help maintain thinking, memory, and speaking skills, and help with certain behavioral problems. However, these drugs don’t change the underlying disease process and may help only for a few months to a few years.
Managing Behavioral Symptoms
Common behavioral symptoms of Alzheimer’s include sleeplessness, agitation, wandering, anxiety, anger, and depression. Scientists are learning why these symptoms occur and are studying new treatments—drug and non-drug—to manage them. Treating behavioral symptoms often makes people with Alzheimer’s more comfortable and makes their care easier for caregivers.
Slowing, Delaying, or Preventing Alzheimer’s Disease
Alzheimer’s disease research has developed to a point where scientists can look beyond treating symptoms to think about addressing the underlying disease process. In ongoing clinical trials, scientists are looking at many possible interventions, such as cardiovascular and diabetes treatments, antioxidants, immunization therapy, cognitive training, and physical activity.
Supporting Families and Caregivers
Caring for a person with Alzheimer’s disease can have high physical, emotional, and financial costs. The demands of day-to-day care, changing family roles, and difficult decisions about placement in a care facility can be hard to handle. Researchers are learning a lot about Alzheimer’s caregiving, and studies are helping experts develop new ways to support caregivers.
Becoming well-informed about the disease is one important long-term strategy. Programs that teach families about the various stages of Alzheimer’s and about flexible and practical strategies for dealing with difficult caregiving situations provide vital help to those who care for people with Alzheimer’s.
Developing good coping skills and a strong support network of family and friends also are important ways that caregivers can help themselves handle the stresses of caring for a loved one with Alzheimer’s disease. For example, staying physically active provides physical and emotional benefits.
Some Alzheimer’s caregivers have found that participating in a support group is a critical lifeline. These support groups allow caregivers to find respite, express concerns, share experiences, get tips, and receive emotional comfort. The Alzheimer’s Association, Alzheimer’s Disease Centers, and many other organizations sponsor in-person and online support groups across the country. There are a growing number of groups for people in the early stage of Alzheimer’s and their families. Support networks can be especially valuable when caregivers face the difficult decision of whether and when to place a loved one in a nursing home or assisted living facility.
Advancing Our Understanding of Alzheimer’s Disease
30-years ago, we knew very little about Alzheimer’s disease. Since then, scientists have made many important advances. Research supported by NIA and other organizations has expanded knowledge of brain function in healthy older people, identified ways we might lessen normal age-related declines in mental function, and deepened our understanding of the disease. Many scientists and physicians are now working together to untangle the genetic, biological, and environmental factors that, over many years, ultimately result in Alzheimer’s. This effort is bringing us closer to the day when we will be able to manage successfully or even prevent this devastating disease.
Lyme disease is an inflammatory disease spread through a tick bite.
Causes of Lyme Disease
Lyme disease is caused by the bacterium Borrelia burgdorferi (B. burgdorferi). Certain ticks carry these bacteria. The ticks pick up the bacteria when they bite mice or deer that are infected with Lyme disease. You can get the disease if you are bitten by an infected tick.
Lyme disease was first reported in the United States in the town of Old Lyme, Connecticut, in 1975. Cases have now been reported in most parts of the United States. Most of the cases occur in the Northeast, some parts of Minnesota and Wisconsin, the mid-Atlantic states, and along the Pacific coast. Lyme disease is usually seen during the late spring, summer, and early fall.
There are 3 stages of Lyme disease.
- Stage 1 is called primary Lyme disease.
- Stage 2 is called secondary Lyme disease and early disseminated Lyme disease.
- Stage 3 is called tertiary Lyme disease and chronic persistent Lyme disease.
Risk factors for Lyme disease include:
- Doing activities that increase tick exposure (for example, gardening, hunting, or hiking)
- Having a pet that may carry ticks home
- Walking in high grasses
Symptoms of Lyme Disease
Not everyone infected with these bacteria gets ill. If a person does become ill, the first symptoms resemble the flu and include:
- Muscle pain
There may be a "bulls eye" rash, a flat or slightly raised red spot at the site of the tick bite. Often there is a clear area in the center. It can be larger than 1 - 3 inches wide.
Symptoms in people with the later stages of the disease include:
- Body-wide itching
- Joint inflammation
- Stiff neck
- Unusual or strange behavior
Note: Deer ticks can be so small that they are almost impossible to see. Many people with Lyme disease never even saw a tick.
Exams and Tests for Lyme Disease
A blood test can be done to check for antibodies to the bacteria that cause Lyme disease. The most commonly used is the ELISA for Lyme disease test. A western blot test is done to confirm ELISA results.
A physical exam may show joint, heart, or brain problems in people with advanced Lyme disease.
Treatment for Lyme Disease
Everyone who has been bitten by a tick should be watched closely for at least 30 days.
Most people who are bitten by a tick do NOT get Lyme disease.
A single dose of antibiotics may be offered to someone soon after being bitten by a tick, if all of the following are true:
- The person has a tick that can carry Lyme disease attached to their body. This usually means that a nurse or physician has looked at and identified the tick.
- The tick is thought to have been attached to the person for at least 36 hours.
- The person can begin taking the antibiotics within 72 hours of removing the tick.
- The person is over 8 years old and is not pregnant or breast-feeding.
A full course of antibiotics is used to treat people who are proven to have Lyme disease. The specific antibiotic used depends on the stage of the disease and the symptoms.
Anti-inflammatory medications, such as ibuprofen, are sometimes prescribed to relieve joint stiffness.
Outlook / Prognosis for Lyme Disease
If diagnosed in the early stages, Lyme disease can be cured with antibiotics. Without treatment, complications involving the joints, heart, and nervous system can occur.
Rarely, a person will continue having symptoms that can interfere with daily life. Some people call this post-Lyme disease syndrome. There is no effective treatment yet for this syndrome.
Possible Complications of Lyme Disease
Advanced stages of Lyme disease can cause long-term joint inflammation (Lyme arthritis) and heart rhythm problems. Nervous system (neurological) problems are also possible, and may include:
- Decreased concentration
- Memory disorders
- Nerve damage
- Paralysis of the face muscles
- Sleep disorders
- Vision problems
Call your health care provider if you have symptoms of Lyme disease.
Prevention of Lyme Disease
When walking or hiking in wooded or grassy areas:
- Spray all exposed skin and your clothing with insect repellant (spray outdoors only, do not use on face, use just enough to cover all other exposed skin, don't spray under clothing, don't apply over wounds or irritated skin, wash skin after going inside)
- Wear light-colored clothing to make it easier to spot ticks
- Wear long-sleeved shirts and long pants with the cuffs tucked into shoes or socks
- Wear high boots, preferably rubber
Check yourself and your pets frequently during and after your walk or hike.
Ticks that carry Lyme disease are so small that they are very hard to see. After returning home, remove your clothes and thoroughly inspect all skin surface areas, including your scalp.
Kidney stones, one of the most painful of the urologic disorders, have beset humans for centuries. Scientists have found evidence of kidney stones in a 7,000-year-old Egyptian mummy. Unfortunately, kidney stones are one of the most common disorders of the urinary tract. Each year, people make almost 3 million visits to health care providers and more than half a million people go to emergency rooms for kidney stone problems.
Most kidney stones pass out of the body without any intervention by a physician. Stones that cause lasting symptoms or other complications may be treated by various techniques, most of which do not involve major surgery. Also, research advances have led to a better understanding of the many factors that promote stone formation and thus better treatments for preventing stones.
What is a Kidney Stone?
A kidney stone is a hard mass developed from crystals that separate from the urine within the urinary tract. Normally, urine contains chemicals that prevent or inhibit the crystals from forming. These inhibitors do not seem to work for everyone, however, so some people form stones. If the crystals remain tiny enough, they will travel through the urinary tract and pass out of the body in the urine without being noticed.
Kidney stones may contain various combinations of chemicals. The most common type of stone contains calcium in combination with either oxalate or phosphate. These chemicals are part of a person’s normal diet and make up important parts of the body, such as bones and muscles.
A less common type of stone is caused by infection in the urinary tract. This type of stone is called a struvite or infection stone. Another type of stone, uric acid stones, are a bit less common, and cystine stones are rare.
Kidney stones in the kidney, ureter, and bladder.
Urolithiasis is the medical term used to describe stones occurring in the urinary tract. Other frequently used terms are urinary tract stone disease and nephrolithiasis. Doctors also use terms that describe the location of the stone in the urinary tract. For example, a ureteral stone—or ureterolithiasis—is a kidney stone found in the ureter. To keep things simple, the general term kidney stones is used throughout this fact sheet.
Gallstones and kidney stones are not related. They form in different areas of the body. Someone with a gallstone is not necessarily more likely to develop kidney stones.
Who gets Kidney Stones?
For unknown reasons, the number of people in the United States with kidney stones has been increasing over the past 30 years. In the late 1970s, less than 4 percent of the population had stone-forming disease. By the early 1990s, the portion of the population with the disease had increased to more than 5 percent. Caucasians are more prone to develop kidney stones than African Americans. Stones occur more frequently in men. The prevalence of kidney stones rises dramatically as men enter their 40s and continues to rise into their 70s. For women, the prevalence of kidney stones peaks in their 50s. Once a person gets more than one stone, other stones are likely to develop.
What Causes Kidney Stones?
Doctors do not always know what causes a stone to form. While certain foods may promote stone formation in people who are susceptible, scientists do not believe that eating any specific food causes stones to form in people who are not susceptible.
A person with a family history of kidney stones may be more likely to develop stones. Urinary tract infections, kidney disorders such as cystic kidney diseases, and certain metabolic disorders such as hyperparathyroidism are also linked to stone formation.
In addition, more than 70 percent of people with a rare hereditary disease called renal tubular acidosis develop kidney stones.
Shapes of various stones. Sizes are usually smaller than shown here.
Cystinuria and hyperoxaluria are two other rare, inherited metabolic disorders that often cause kidney stones. In cystinuria, too much of the amino acid cystine, which does not dissolve in urine, is voided, leading to the formation of stones made of cystine. In patients with hyperoxaluria, the body produces too much oxalate, a salt. When the urine contains more oxalate than can be dissolved, the crystals settle out and form stones.
Hypercalciuria is inherited, and it may be the cause of stones in more than half of patients. Calcium is absorbed from food in excess and is lost into the urine. This high level of calcium in the urine causes crystals of calcium oxalate or calcium phosphate to form in the kidneys or elsewhere in the urinary tract.
Other causes of kidney stones are hyper uricosuria, which is a disorder of uric acid metabolism; gout; excess intake of vitamin D; urinary tract infections; and blockage of the urinary tract. Certain diuretics, commonly called water pills, and calcium-based antacids may increase the risk of forming kidney stones by increasing the amount of calcium in the urine.
Calcium oxalate stones may also form in people who have chronic inflammation of the bowel or who have had an intestinal bypass operation, or ostomy surgery. As mentioned earlier, struvite stones can form in people who have had a urinary tract infection. People who take the protease inhibitor indinavir, a medicine used to treat HIV infection, may also be at increased risk of developing kidney stones.
Foods and Drinks Containing Oxalate
People prone to forming calcium oxalate stones may be asked by their doctor to limit or avoid certain foods if their urine contains an excess of oxalate.
High-oxalate foods—higher to lower
- swiss chard
- wheat germ
- soybean crackers
- black Indian tea
- sweet potatoes
Foods that have medium amounts of oxalate may be eaten in limited amounts.
Medium-oxalate foods—higher to lower
- green pepper
- red raspberries
- fruit cake
What are the Symptoms of Kidney Stones?
Kidney stones often do not cause any symptoms. Usually, the first symptom of a kidney stone is extreme pain, which begins suddenly when a stone moves in the urinary tract and blocks the flow of urine. Typically, a person feels a sharp, cramping pain in the back and side in the area of the kidney or in the lower abdomen. Sometimes nausea and vomiting occur. Later, pain may spread to the groin.
If the stone is too large to pass easily, pain continues as the muscles in the wall of the narrow ureter try to squeeze the stone into the bladder. As the stone moves and the body tries to push it out, blood may appear in the urine, making the urine pink. As the stone moves down the ureter, closer to the bladder, a person may feel the need to urinate more often or feel a burning sensation during urination.
If fever and chills accompany any of these symptoms, an infection may be present. In this case, a person should contact a doctor immediately.
How are Kidney Stones Diagnosed?
Sometimes “silent” stones—those that do not cause symptoms—are found on x rays taken during a general health exam. If the stones are small, they will often pass out of the body unnoticed. Often, kidney stones are found on an x ray or ultrasound taken of someone who complains of blood in the urine or sudden pain. These diagnostic images give the doctor valuable information about the stone’s size and location. Blood and urine tests help detect any abnormal substance that might promote stone formation.
The doctor may decide to scan the urinary system using a special test called a computerized tomography (CT) scan or an intravenous pyelogram (IVP). The results of all these tests help determine the proper treatment.
Preventing Kidney Stones
A person who has had more than one kidney stone may be likely to form another; so, if possible, prevention is important. To help determine their cause, the doctor will order laboratory tests, including urine and blood tests. The doctor will also ask about the patient’s medical history, occupation, and eating habits. If a stone has been removed, or if the patient has passed a stone and saved it, a stone analysis by the laboratory may help the doctor in planning treatment.
The doctor may ask the patient to collect urine for 24 hours after a stone has passed or been removed. For a 24-hour urine collection, the patient is given a large container, which is to be refrigerated between trips to the bathroom. The collection is used to measure urine volume and levels of acidity, calcium, sodium, uric acid, oxalate, citrate, and creatinine—a product of muscle metabolism. The doctor will use this information to determine the cause of the stone. A second 24-hour urine collection may be needed to determine whether the prescribed treatment is working.
How are Kidney Stones Treated?
Fortunately, surgery is not usually necessary. Most kidney stones can pass through the urinary system with plenty of water—2 to 3 quarts a day—to help move the stone along. Often, the patient can stay home during this process, drinking fluids and taking pain medication as needed. The doctor usually asks the patient to save the passed stone(s) for testing. It can be caught in a cup or tea strainer used only for this purpose.
Lifestyle Changes to Prevent Kidney Stones
A simple and most important lifestyle change to prevent stones is to drink more liquids—water is best. Someone who tends to form stones should try to drink enough liquids throughout the day to produce at least 2 quarts of urine in every 24-hour period.
In the past, people who form calcium stones were told to avoid dairy products and other foods with high calcium content. Recent studies have shown that foods high in calcium, including dairy products, may help prevent calcium stones. Taking calcium in pill form, however, may increase the risk of developing stones.
Patients may be told to avoid food with added vitamin D and certain types of antacids that have a calcium base. Someone who has highly acidic urine may need to eat less meat, fish, and poultry. These foods increase the amount of acid in the urine.
To prevent cystine stones, a person should drink enough water each day to dilute the concentration of cystine that escapes into the urine, which may be difficult. More than a gallon of water may be needed every 24 hours, and a third of that must be drunk during the night.
Medical Therapy for Kidney Stones
A doctor may prescribe certain medications to help prevent calcium and uric acid stones. These medicines control the amount of acid or alkali in the urine, key factors in crystal formation. The medicine allopurinol may also be useful in some cases of hyper uricosuria.
Doctors usually try to control hypercalciuria, and thus prevent calcium stones, by prescribing certain diuretics, such as hydrochlorothiazide. These medicines decrease the amount of calcium released by the kidneys into the urine by favoring calcium retention in bone. They work best when sodium intake is low.
Rarely, patients with hypercalciuria are given the medicine sodium cellulose phosphate, which binds calcium in the intestines and prevents it from leaking into the urine.
If cystine stones cannot be controlled by drinking more fluids, a doctor may prescribe medicines such as Thiola and Cuprimine, which help reduce the amount of cystine in the urine.
For struvite stones that have been totally removed, the first line of prevention is to keep the urine free of bacteria that can cause infection. A patient’s urine will be tested regularly to ensure no bacteria are present.
If struvite stones cannot be removed, a doctor may prescribe a medicine called acetohydroxamic acid (AHA). AHA is used with long-term antibiotic medicines to prevent the infection that leads to stone growth.
People with hyperparathyroidism sometimes develop calcium stones. Treatment in these cases is usually surgery to remove the parathyroid glands, which are located in the neck. In most cases, only one of the glands is enlarged. Removing the glands cures the patient’s problem with hyperparathyroidism and kidney stones.
Surgical Treatment for Kidney Stones
Surgery may be needed to remove a kidney stone if it
- does not pass after a reasonable period of time and causes constant pain
- is too large to pass on its own or is caught in a difficult place
- blocks the flow of urine
- causes an ongoing urinary tract infection
- damages kidney tissue or causes constant bleeding
- has grown larger, as seen on follow-up x rays
Until 20 years ago, open surgery was necessary to remove a stone. The surgery required a recovery time of 4 to 6 weeks. Today, treatment for these stones is greatly improved, and many options do not require major open surgery and can be performed in an outpatient setting.
Extracorporeal Shock Wave Lithotripsy
Extracorporeal shock wave lithotripsy (ESWL) is the most frequently used procedure for the treatment of kidney stones. In ESWL, shock waves that are created outside the body travel through the skin and body tissues until they hit the denser stones. The stones break down into small particles and are easily passed through the urinary tract in the urine.
Several types of ESWL devices exist. Most devices use either x rays or ultrasound to help the surgeon pinpoint the stone during treatment. For most types of ESWL procedures, anesthesia is needed.
In many cases, ESWL may be done on an outpatient basis. Recovery time is relatively short, and most people can resume normal activities in a few days.
Complications may occur with ESWL. Some patients have blood in their urine for a few days after treatment. Bruising and minor discomfort in the back or abdomen from the shock waves can occur. To reduce the risk of complications, doctors usually tell patients to avoid taking aspirin and other medicines that affect blood clotting for several weeks before treatment.
Sometimes, the shattered stone particles cause minor blockage as they pass through the urinary tract and cause discomfort. In some cases, the doctor will insert a small tube called a stent through the bladder into the ureter to help the fragments pass. Sometimes the stone is not completely shattered with one treatment, and additional treatments may be needed.
As with any interventional, surgical procedure, potential risks and complications should be discussed with the doctor before making a treatment decision.
Sometimes a procedure called percutaneous nephrolithotomy is recommended to remove a stone. This treatment is often used when the stone is quite large or in a location that does not allow effective use of ESWL.
In this procedure, the surgeon makes a tiny incision in the back and creates a tunnel directly into the kidney. Using an instrument called a nephroscope, the surgeon locates and removes the stone. For large stones, some type of energy probe—ultrasonic or electrohydraulic—may be needed to break the stone into small pieces. Often, patients stay in the hospital for several days and may have a small tube called a nephrostomy tube left in the kidney during the healing process.
One advantage of percutaneous nephrolithotomy is that the surgeon can remove some of the stone fragments directly instead of relying solely on their natural passage from the kidney.
Ureteroscopic Stone Removal
Although some stones in the ureters can be treated with ESWL, ureteroscopy may be needed for mid- and lower-ureter stones. No incision is made in this procedure. Instead, the surgeon passes a small fiber optic instrument called a ureteroscope through the urethra and bladder into the ureter. The surgeon then locates the stone and either removes it with a cage-like device or shatters it with a special instrument that produces a form of shock wave. A small tube or stent may be left in the ureter for a few days to help urine flow. Before fiber optics made ureteroscopy possible, physicians used a similar “blind basket” extraction method. But this technique is rarely used now because of the higher risks of damage to the ureters.
New medicines and the growing field of lithotripsy have greatly improved the treatment of kidney stones. Still, NIDDK researchers and grantees seek to answer questions such as
- Why do some people continue to have painful stones?
- How can doctors predict, or screen, those at risk for getting stones?
- What are the long-term effects of lithotripsy?
- Do genes play a role in stone formation?
- What is the natural substance(s) found in urine that blocks stone formation?
Researchers are also developing new medicines with fewer side effects.
Things to Remember about Kidney Stones
- A person with a family history of stones or a personal history of more than one stone may be more likely to develop more stones.
- A good first step to prevent the formation of any type of stone is to drink plenty of liquids—water is best.
- Someone who is at risk for developing stones may need certain blood and urine tests to determine which factors can best be altered to reduce that risk.
- Some people will need medicines to prevent stones from forming.
- People with chronic urinary tract infections and stones will often need a stone removed if the doctor determines that the stone is causing the infection. Patients must receive careful follow-up to be sure that the infection has cleared.