Cancer cluster: A greater-than-expected number of cancer cases that occurs within a group of people in a geographic area over a period of time. The expected number of cancer cases is calculated and compared to the observed number of cancer cases. A cancer cluster is confirmed when the observed/expected ratio is greater than 1.0, and the difference is statistically significant.

What first appears to be a cancer cluster may not be one. Scrutiny of the situation may show that the number of cancer cases is within the expected range for the population.

Cancer cases are most likely to represent a cancer cluster if they involve: (1) one type of cancer, (2) a rare type of cancer, or (3) a type of cancer in a group not usually affected by that cancer. For example, a cancer normally seen in adults occurs in children.

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Favism: A condition characterized by hemolytic anemia (breakup of red blood cells) after eating fava beans (Vicia fava) or being exposed to the pollen of the fava plant. This dangerous reaction occurs exclusively in people with a deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD), an X-linked genetic trait. However, not all G6PD-deficient families appear at risk for favism, indicating the additional need for a single autosomal (not X-linked) gene to create the susceptibility to favism of G6PD-deficient persons. The active hemolytic principle in fava beans is > likely DOPA-quinone. Differences in susceptibility to favism may be related to differences in the enzymatic system that converts L-DOPA to DOPA-quinone.

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Adequate relief from pain difficult to find with neuropathies.

Child development chart — Know what milestones to expect from ages 2 to 5.

Diet and exercise are proven ways to reduce cholesterol. Cholesterol-lowering supplements may help, too.

Granuloma annulare — Comprehensive overview covers symptoms, treatment of this chronic skin condition.

Hyperhidrosis — Comprehensive overview covers causes, symptoms and treatments for excessive sweating.

Vagus nerve stimulation — Overview covers definition, risks, results of this procedure to treat depression.

Colonoscopy: A procedure in which a long flexible viewing tube (a colonoscope) is threaded up through the rectum for the purpose of inspecting the entire colon and rectum and, if there is an abnormality, taking a biopsy of it or removing it. The colonoscopy procedure requires a thorough bowel cleansing to assure a clear view of the lining. Called also coloscopy.

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Deep brain stimulation — Overview covers definition, risks, results of this experimental depression treatment.

Migraine headache, tension headache, cluster headache — how each type affects you.

Primary progressive aphasia — Comprehensive overview covers symptoms, treatment of this speech-related dementia.

Coxsackievirus: A family of enteroviruses first found in the town Coxsackie south of Albany, New York. The Coxsackieviruses are separable into two groups: A and B. Type A viruses cause herpangina (sores in the throat) and hand, foot and mouth disease. Type B viruses cause epidemic pleurodynia. Both types A and B viruses can cause meningitis, myocarditis and pericarditis, and acute onset juvenile diabetes. Sometimes written Coxsackie virus. See also: Enterovirus.

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No one lives forever, so why do so many people keep trying?

Normal weight obesity — normal BMI but too much body fat — can be a health risk.

Septic arthritis — Comprehensive overview covers symptoms and treatment of joint infections caused by bacteria.

Congestive heart failure: Inability of the heart to keep up with the demands on it and, specifically, failure of the heart to pump blood with normal efficiency. When this occurs, the heart is unable to provide adequate blood flow to other organs such as the brain, liver and kidneys. Heart failure may be due to failure of the right or left or both ventricles. The signs and symptoms depend upon which side of the heart is failing. They can include shortness of breath (dyspnea), asthma due to the heart (cardiac asthma), pooling of blood (stasis) in the general body (systemic) circulation or in the liver's (portal) circulation, swelling (edema), blueness or duskiness (cyanosis), and enlargement (hypertrophy) of the heart.

There are many causes of congestive heart failure including: (1) coronary artery disease leading to heart attacks and heart muscle weakness, (2) primary heart muscle weakness from viral infections or toxins such as prolonged alcohol exposure, (3) heart valve disease causing heart muscle weakness due to too much leaking of blood or heart muscle stiffness from a blocked valve, and (4) hypertension (high blood pressure). Rarer causes include hyperthyroidism (high thyroid hormone), vitamin deficiency, and excess amphetamine ("speed") use.

The aim of therapy is to improve the pumping function of the heart. General treatment includes salt restriction, diuretics (to get rid of excess fluid), digoxin (to strengthen the heart), and other medications. A drug called spironolactone has been found to be a major help in treating congestive heart failure Its beneficial effects are additive to those from ACE inhibitors, another class of drugs commonly relied on in treating heart failure. A pacemaker-like device is also now available to treat heart failure. The implantable device delivers synchronized electrical stimulation to three chambers of the heart, enabling the heart to pump blood more efficiently throughout the body.

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As a caregiver, provide a sense of control to your loved one with dementia.

Vitamin B-12 injections — A weight-loss shot sounds appealing, but does it work?

Exclamation point hair: Exclamation point hair is a key diagnostic finding in a disorder called alopecia areata.

Alopecia areata is patchy baldness (alopecia means baldness and areata means occurring in patches) which typically begins with patchy hair loss on the scalp and sometimes progresses to complete baldness and even loss of body hair. The hair loss tends to be rather rapid and asymmetrical and is different than male pattern baldness.

Alopecia areata affects both males and females. It tends to occur most often in children and young adults but older individuals can also be affected.

The most common pattern of alopecia areata is one or more spots of hair loss on the scalp. There is also a form with more generalized thinning. When all of the scalp hair is lost, it is called alopecia totalis. Loss of all of the hairs on the body is called alopecia universalis.

The cause appears to involve an autoimmune mechanism. The body's own immune system attacks the hair follicles and disrupts normal hair formation. Biopsies of affected skin show lymphocytes (one of the body's immune system cells) inside of hair follicles where lymphocytes normally are not present. What causes this is unknown.

Alopecia areata is sometimes associated with other conditions (allergic disorders, thyroid disease, vitiligo, lupus, rheumatoid arthritis, ulcerative colitis). Some cases occur within family members and indicate a genetic basis.

The characteristic diagnostic finding of alopecia areata is the exclamation point hair. These can be found in areas of hair loss and are short broken off hairs that are narrower closer to the scalp and therefore mimic an exclamation point. In some cases a biopsy is necessary for diagnosis.

In about half of cases, the hair regrows within a year without any treatment. The longer the period of time of hair loss, the less chance that it will regrow and a variety of treatments can be tied. Steroid injections and cream to the scalp have been used for many years. Other drugs include minoxidil, irritants, and topical immunotherapy which may be used in different combinations.

A study reported in the journal Archives of Dermatology (Vol 134, 1998;1349-52) showed effectiveness of aromatherapy essential oils (cedarwood, lavender, thyme, and rosemary oils) in some patients. As with many disorders for which there is no clear cut beneficial treatment, a variety of remedies are promoted which in fact have no benefit.

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