Disorders

(Addison's disease, adrenal virilism, aldosteronism. Conn's syndrome, Cushings syndrome, pheochromocytoma)

The adrenal glands produce a number of hormones, complex chemical substances that regulate many vital functions of the body. These include adrenaline, also called epinephrine, and other hormones released during stress; hydrocortisone and other steroids, which help control the immune system as well as regulate blood glucose levels and blood pressure; aldosterone, which maintains fluid and chemical balances; and androgens, progesterone, and estrogen, which are essential for reproduction. Some of these hormones are also produced elsewhere in the body, but the adrenal cortex is the sole source of epinephrine, aldosterone, and hydrocortisone.

The urinary bladder is a muscular pouch that can expand to hold about a pint of urine. When almost half full, the bladder begins signaling a feeling of fullness. During urination, the bladder muscle contracts to release urine in such a way that it cannot flow back into the ureters, the tubes linking the kidneys and bladder.

Bladder disorders may occur as a result of an injury, disease, or an inherited condition. Anatomical differences between men and women predispose them to different bladder problems. Women are much more prone than men to bladder and urethral infections, because their urethra is very short and located close to the anus and the vagina, sites that often harbor bacteria that can invade the bladder. Prostate gland disorders account for many of the male bladder problems.

Two of the most serious eating disorders are anorexia nervosa, a complex disease characterized by a distorted body image and self-starvation, and bulimia, which involves eating huge quantities of food followed by purging, usually through self-induced vomiting and/or laxative abuse. More than 90 percent of those with either of these conditions are adolescent girls or young women; boys are affected only occasionally. Some persons have features of both disorders.

(Dysphagia, esophageal diverticula, spasm, stricture, varices, and webs)

The esophagus, or gullet, is a muscular tube, approximately 10 inches long, that extends from the mouth to the stomach. It is sometimes called the food pipe to distinguish it from the nearby windpipe, or trachea. Valve mechanisms at both the upper and lower ends, as well as gravity and a wavelike muscular motion called peristalsis, keep food moving through the esophagus in the right direction.

(Mitral, Aortic, Tricuspid, and Pulmonary Stenosis and Regurgitation)

The heart has four valves that control the flow of blood passing in and out of its chambers. A defect or disease in any one of them will disrupt normal flow. There are two categories of disorder: stenosis, in which a valve fails to open fully, and insufficiency, or regurgitation, in which it does not close properly.

Hemophilia is an inherited disorder in which the blood fails to clot normally. It is characterized by heavy bleeding after a minor injury, spontaneous bruising, and frequent nosebleeds. Joints, particularly the knee and elbow, are often swollen and painful due to bleeding into the joint space.

A person with hemophilia lacks a clotting factor, a protein that goes into action when the wall of a blood vessel is damaged. In hemophilia A, about 80 percent of all cases, the deficiency is in clotting factor VIII. In hemophilia B, clotting factor IX is lacking. Both produce the same symptoms, but treatment differs in that the specific missing clotting factor must be replaced.

After many years of research and debate, hyperactivity is now classified as an aspect of disruptive behavior disorders. The preferred medical term is attention-deficit/hyperactivity disorder, or ADHD. It has previously been called minimal brain dysfunction, hyperkinesis, and hyperactive child syndrome.

The term inflammatory bowel disease describes a chronic condition of intestinal inflammation and ulceration that has no identifiable cause. The two most common examples are Crohn's disease and ulcerative colitis.

Crohn's disease, also called ileitis or regional enteritis, can affect any part of the gastrointestinal system, from the mouth to the anus, but most often attacks the lowermost portion of the small intestine, or ileum, and the colon. The disease usually appears early in life, commonly between the ages of 14 and 24. Men and women are equally affected and, for unknown reasons, there has been a worldwide increase in the disease since it was first described by Dr. Burrill B. Crohn, a New York gastroentcrologist, in the 1930s.

Learning disabilities are generally defined as developmental problems that interfere with a child's ability to process information. In the broadest sense, this definition covers mental retardation and such neurological disorders as hyperactivity, but this discussion focuses on difficulties that disappear in time or are highly treatable. Although there may be some overlap, most learning disabilities fall into three categories:

1. Disorders affecting academic skills, most commonly reading or math. Included are such perceptual problems as dyslexia, which causes difficulty in learning to read; excluded are blindness and other sensory impairments.
2. Disorders affecting language and speech. The milder forms, which include lisping and stuttering, are probably the most common of all learning disabilities, as well as the most benign. More serious, but less common, examples include an inability to form sentences or difficulty in understanding certain sounds or words.
3. Disorders affecting coordination or other motor skills in the absence of neurological, muscular, or other physical problems. These include difficulty learning to write, tie shoelaces, work puzzles, and perform other tasks that require fine coordination.

Numerous occupations expose workers to chemicals, gases, dust, and toxins that can damage the lungs. Asbestos is one of the most familiar of occupational lung hazards, but there are others that are even more lethal. Types of occupational lung disorders include: Pneumoconiosis, caused by industrial dusts or fibers. Asbestosis, a result of inhaling asbestos particles, falls into this category.

(Albinism; Hyper- and Hypopigmentalion, Melanocyte or Pigmented Nevi, Melasma, Moles)

Pigment disorders are discolorations of the epidermis, the outermost layer of the skin, which gets its color from melanin, a chemical produced by a specific type of skin cells called melanocytes. The affected skin may appear bleached -- hypopigmented -- from insufficient melanin; or it may have become abnormally dark -- hyperpigmented -- due to excessive melanin.

The retina, the thin membrane that lines the back of the eyeball, receives the images formed by the lens and transmits them to the optic nerve, an extension of the brain. Anything that interferes with the retina's ability to receive or transmit visual images can impair eyesight. A problem may originate in the membrane itself; examples are detached retina and macular degeneration. It may also result from occlusion of blood flow to the retina due to glaucoma. The retinal disorders described below are either hereditary or are caused by other diseases.

When the brains normal electrical activity is disrupted, seizures, or convulsions, can occur. They are classified as generalized or partial, with variations in each category. Generalized seizures include the following:

Tonic-clonic, or grand mat. The person abruptly halts all activity and loses consciousness briefly. This tonic phase lasts for only a few seconds and is characterized by a sustained contraction of muscles. The subsequent clonic phase may last for five minutes, during which time muscles spontaneously relax and contract, creating convulsive twitching. If only one phase occurs, it is called either clonic or tonic.

Atonic, or drop attach. The person suddenly loses muscle tone, goes limp, and is unconscious for several minutes.

Myoclonic. The person usually remains conscious, but exhibits brief, random contractions and twitching of a muscle.

Absence, or petit mal. The person, usually a child, has a brief episode of altered awareness, in which he stares blankly ahead.

Partial seizures may involve muscles, sensory organs, or menial function, but do not result in generalized convulsions. In some occurrences, muscles may twitch in a specific area, such as a leg, or there may be localized tingling. Others involve brief mental lapses that are similar to absence seizures. A common partial seizure is characterized by repetitive motions that are a continuation of an activity but lacking in purpose. For example, a child might continue a writing motion without actually forming letters.

Epilepsy, the most common seizure disorder, is characterized by recurrent seizures that follow a specific pattern.

Diagnostic Studies and Procedures

Seizures can be diagnosed from symptoms and an eyewitness account of an attack, but determining the cause is often difficult, sometimes impossible. Tests include blood studies, an electroencephalogram (EEG) to measure the brain's electrical activity. X-rays, and perhaps a CT scan or MRI.

Medical Treatments

Medication with anticonvulsant drugs can prevent seizures or reduce their frequency. Commonly used anticonvulsant medications are phenytoin (Dilantin), phenobarbital, primidone (Mysoline), carbamazepine (Tegretol), eihosuximide (Zarontin), clonazepam (Klonopin), and valproic acid (Depakene). The side effects vary, but may include lethargy, drowsiness, dizziness, nausea and vomiting, gait problems, and mental changes.

Finding the right drug or combination of drugs usually involves a period of trial and error. Once a regimen is found to work however, the patient should stay on it. This is one instance in which a generic drug should not be substituted for a brand-name product. Even though the active ingredients may be the same, the two drugs may react differently in the body. Some patients are eventually able to discontinue their medication, while others must remain on it for life.

Surgery may be tried if seizures cannot be controlled by drugs.

Alternative Therapies

Nutrition Therapy. Fasting has been known to eliminate seizures, but this was hardly a feasible treatment for epilepsy until neurologists at Johns Hopkins devised a diet that mimics fasting metabolism. The regimen calls for a high intake of fats, only enough protein for growth, and little or no carbohydrates. This ketogenic diet is recommended mostly for children whose epilepsy cannot be controlled by drugs or who suffer severe side effects from anticonvulsants. It must be tailored individually and followed carefully; after two years, most children can resume a normal diet without recurrence of seizures.

Meditation. This and other relaxation techniques may be helpful for seizures that are triggered by stress.

Self-Treatment

Some people can modify their tendency to have seizures by identifying and then avoiding triggering factors. An orderly, moderate lifestyle, adequate rest, and a nutritious diet help most patients. Others with severe seizures may benefit-from the Johns Hopkins ketogenic diet.

Anyone who has a seizure disorder should wear a medical identification bracelet or necklace that lists the illness and an emergency phone number.

Other Causes of Seizures

A rapidly rising temperature can produce febrile seizures, especially in babies. A brain injury, certain drugs, poisons, lack of oxygen, and either high or low blood sugar can cause seizures.

Sweating, or perspiring, helps remove some of the body's wastes through the pores of the skin. It also aids in regulating the body's temperature by cooling through evaporation, and it provides an acidic coating that controls the growth of skin bacteria.

Two types of glands -- apocrine and eccrine -- produce sweat, but their production differs. Apocrine glands, which enlarge as puberty approaches, are located in the armpits, where they are the most active, as well as selected areas of skin on the trunk, face, and scalp. They exude a scant amount of milky perspiration that contains proteins, carbohydrates, and lipids, which give it a somewhat unpleasant smell as these substances are broken down by bacteria. Apocrine sweat is thought to broadcast sexual signals through the odor of a group of chemicals known as pheromones. Nothing inhibits the production of this sweat, but deodorants diminish its smell.

The senses of taste and smell are so closely related physiologically that a disorder affecting one is likely to have an adverse effect on the other as well. An estimated 80 to 90 percent of the people who think they have lost their sense of taste have actually lost their ability to smell instead.

The sense of smell declines sharply with age; studies show that more than half of Americans aged 65 to 80, and three-fourths of those over 80, have serious problems in detecting or identifying odors. A significant number in both age groups cannot smell at all.

(Goiter; Graves' Disease; Hashimotos Disease; Hyperthyroidism; Hypothyroidism; Myxedema)

The thyroid, a butterfly-shaped gland that rests over the windpipe at the base of the neck, produces hormones that regulate metabolism and many other body processes. Both an overproduction (hyperthyroidism) or an underproduction (hypothyroidism) of these hormones can have a profound effect on almost all body functions.

(Astigmatism; Color Blindness; Near- and Farsightedness; Presbyopia)

Vision is a complex and delicate process that can be affected by injuries, aging, and various diseases. Vision problems are due mainly to errors of refraction -- the way in which the lens of the eye focuses light on the retina at the rear of the eye. The most familiar are:

Astigmatism, in which the cornea, the transparent membrane at the front of the eye, is misshapen. Light rays fail to focus on a single point of the retina, resulting in distorted images.

Farsightedness, or hyperopia, in which light rays focus at a point just beyond the retina, blurring near objects.

Nearsightedness, or myopia, in which light rays focus just before the retina, making far objects difficult to see.

Presbyopia, a condition that develops with age, in which the lens loses some elasticity, resulting in farsightedness.

Color blindness, in which the cone cells of the retina are unable to distinguish the full spectrum of colors. Most color blindness is hereditary, affecting men 10 times more often than women. Other forms may develop with age or be secondary to diabetes, glaucoma, medications, or accidental poisoning.

Diagnostic Studies and Procedures

Most vision problems are readily diagnosed by an ophthalmologist or optometrist. These eye specialists test visual acuity with a Snellen test, a chart with rows of letters or numbers in different sizes. (Special picture charts are used to test young children.) Typically, the patient reads the chart, first using the naked eye and then with special lenses or instruments. Peripheral vision may be tested by a device that blinks lights on and off while the person looks into it.

If a color vision problem is suspected, the patient will be shown patterns of colored dots and asked to identify objects traced in different colors. Eye drops may be given to dilate the pupils, in order to inspect the inside of the eye.

Medical Treatments

Vision problems involving refraction errors are usually treated successfully with corrective glasses or contact lenses that refocus the light rays on the retina. Because vision changes over time, a prescription for corrective lenses must also be changed periodically. With advancing age, more than one lens strength may be needed, which can be combined into bifocal glasses.

Color vision abnormalities are sometimes treated with colored contact lenses, but these reduce visual acuity, distort three-dimensional perception, and offer little help with light shades, generally the major problem area.

Nearsightedness can be corrected with radial keratotomy. This outpatient surgical technique, developed in Russia, involves making a series of tiny radial incisions in the cornea. Each eye is done separately, with several days between operations. An eye patch or dark glasses are worn for several days. The full effects may not be felt for several months.

In one long-term follow-up study, more than half of the patients reported fully corrected vision, and another one-fourth said their eyesight was improved. Anyone contemplating radial keratotomy should make sure that the surgeon has a high success rate.

Alternative Therapies

Exercises. In the Bates method, exercises are used to improve poor or weak eyesight. Ophthalmologists discount their value, but others contend that the exercises balance the optic muscles, nerve, and other eye structures.

Nutrition Therapy. High doses of vitamin A are reputed to improve faulty color vision, but this has not been proven. However, vitamin A is essential for night vision; good sources include yellow and dark green vegetables.

Self-Treatment

To test yourself for a possible refractive error, make a pinhole in a piece of paper and look through the hole at a well-lit object. If the object is clearer this way, you probably need corrective lenses. If not, your blurred vision may be due to another disorder. In either case, seek professional care.

Other Causes of Vision Disorders

Glaucoma, cataracts, and certain retinal disorders are some conditions that impair vision. Amblyopia, or lazy eye syndrome, is common in children and may occur with strabismus, or crossed eyes. Diabetes and untreated high blood pressure can also affect the eyes as can many drugs.