Angina Pectoris

Angina Pectoris, symptom of reduced oxygen supply to the heart muscle, usually caused by narrowing or obstruction of the coronary artery. It is marked by a viselike squeezing sensation beneath the breastbone. Pain may radiate from the front of the chest, often into the arm. The attacks usually last several minutes. They may be caused by emotional stress but are more likely to result from physical activities that require an increased supply of blood to the heart. The disease occurs most commonly in middle-aged and older people, particularly those who suffer from arteriosclerosis. Relief is obtained by rest and relaxation. Patients can be treated with drugs that relax and dilate blood vessels or that slow the heart, and surgery can be performed to improve coronary circulation. The attacks themselves cause no damage.

Bone Disease

A variety of diseases affect bones. One of the most common bone diseases is osteoporosis, which is characterized by a thinning of bone tissue, causing bones to become weak, brittle, and prone to fractures. Many factors can cause osteoporosis, including menopause, lack of exercise, low calcium intake, smoking, use of steroid drugs, and excessive consumption of alcohol.

Dietary deficiencies of calcium, phosphorus, and vitamin D cause rickets, a disease characterized by abnormal bone formation and skeletal deformities. Rickets is most common in children. Dietary deficiencies of these nutrients in adults-or metabolic disorders that cause poor absorption of the nutrients-can result in an abnormal softening of bone, a condition called osteomalacia.

Infections of bones called osteomyelitis usually are caused by bacteria, especially Staphylococcus, which enters the body through open wounds and may destroy bone tissues. Tumors, or abnormal growths, occur in bone tissue, though most are benign. Cancerous tumors can be caused by excessive radiation; many radioactive substances have an affinity for bone, particularly the marrow, and are readily stored there. Most cancerous tumors in bones, however, are tumors that spread from cancer in other parts of the body. Cancers that arise in bone, cartilage, and other connective tissues are called sarcomas.

Ailments of the Digestive System

Infection of or damage to any part of the digestive system may affect digestion as well as other bodily functions. Common infectious agents that attack digestive organs include the mumps virus, which often infects the salivary glands; the bacterium Helicobacter pylori, which causes most stomach and duodenal ulcers; and viruses and bacteria that cause various forms of gastroenteritis, often called stomach flu or traveler’s diarrhea. Appendicitis is an inflammation of the appendix, a tube-like pouch about 9 cm (3.5 in) long that branches off the large intestine. It occurs most commonly among children and young adults. Diarrhea—frequent elimination of loose, watery feces—is a symptom of many disorders that occurs when the large intestine is irritated or inflamed. As a result, food residues move through it too quickly for it to absorb the excess water. The opposite condition, constipation, occurs when the large intestine absorbs too much water because food residues are moving slowly. As a result, the feces become hard and dry, which may make elimination difficult.

Cancerous tumors may develop in any part of the digestive system, though they most commonly occur in the large intestine, rectum, and anus (see Colorectal Cancer). Colitis, which has various causes, is a potentially life-threatening inflammation of the large intestine (see Ulcerative Colitis). Chronic conditions that cause at least intermittent distress include irritable bowel syndrome, caused by spasms of muscles in the lower intestine, and Crohn’s disease, an inflammation of the intestines. Abnormal sensitivity to proteins called glutens can damage the lining of the small intestine and hinder absorption of nutrients, leading to malnutrition and other problems. The eating disorders anorexia nervosa and bulimia disrupt the normal functioning of the digestive system and are potentially fatal.

Testicular Cancer and Disorders

Occasionally—in 2 percent of full term and 10 percent of premature male babies—one or, more rarely, both testes will fail to descend from the abdomen into the scrotum during embryonic development. Often the affected testis will descend on its own within a few months of birth. Undescended testis is sometimes caused by dysfunctional hormones that control the development of the spermatic cord, which is comprised of the vas deferens and supporting nerves and blood vessels. When the hormones do not send the correct signals, the spermatic cord does not lengthen sufficiently for the testis to descend, develop normally, and eventually produce sperm. If neither testis descends, the man will be infertile. The problem may be corrected by surgery within the first few years of life.

A direct blow to the scrotum or twisting of the testis and spermatic cord may cause painful swelling. If pain is accompanied by fever, the swelling may be caused by infection of the testis or epididymis. Swelling without pain may indicate excess fluid or sperm in the epididymis, the presence of varicose veins in the scrotum, or collected blood in the scrotum as a result of injury. Less frequently, painless swelling may be one of the first signs of testicular cancer.

Testicular cancer is often detected by the man himself as a firm, usually painless lump in the testis. A physician conducts a complete medical exam and history, along with blood and urine tests and chest X rays to exclude other causes. If these are ruled out, a biopsy (removal and microscopic examination of cell tissue) is performed on testicular tissue to confirm a diagnosis of cancer. The testicle must then be removed through the groin (a surgical process called orchiectomy). Additional treatment may involve radiation therapy on the remaining testis and lymph glands, or chemotherapy, or a combination of both.

Because early detection is so important in achieving a successful cure, men should perform testicular self-examination once a month, looking for unusual changes in the appearance and feel of the scrotum.

Hypothalamus Disorders

Damage to the hypothalamus can result from surgery, trauma (such as accident or stroke), degeneration due to old age or disease, or a tumor. The results of damage can be varied and depend on the areas of the hypothalamus involved.

Diabetes insipidus can be caused by hypothalamic damage, or by damage to the hypothalamic-pituitary tract. This disease reduces vasopressin production, resulting in large volumes of urine being produced at all times.

Other hypothalamic disorders can include sexual abnormalities (such as premature puberty), psychic disturbances, obesity, anorexia, temperature regulation disorders, sleep disorders, and disruption of normal circadian rhythms.