Hansen's Disease

Hansen's disease, or known as leprosy, a chronic infectious disease, which involves primarily the skin and the peripheral nerves. Altough it's primarily a tropical disease, it has occurred as far North as Norway and Iceland.

The leprosy bacterium was first describe by the Norwegian physician, G. Armauer Hansen, in 1874. Its structure and characteristics is similar to the organism which causes tuberculosis. The bacteria are believed to be transmitted by direct contact.

Though it's not easily spread, but more than 5% of persons married to a person suffering from leprosy will become infected with the disease. The average period of incubation is five years or more.

Body Disturbances

The disturbances seen in leprosy are extremely variable. Skin is usually affected early while nerve damage appears later. There are many disabling phenomena result from nerve damage rather than infection.

The ulcers of the feet and the fingers are caused by damage resulting from of the infection along the nerves of the extremities. Facial disfigurement is seen only in advanced stages, when the infection is untreated.

Skin lesions vary from simple spots to thick infiltrations and nodule formation. The severity of the infections depends upon the type of leprosy. The most severe cases are caused by the lepromatous, which progresses steadily, and involves infiltration of the skin, producing nodular lesions.

The milder tuberculoid form usually improves spontaneously. In many instances, tuberculoid leprosy would be an unimportant skin condition were it not for the associated nerve involvement.

Leprosy is rarely fatal in itself. Death, when it occurs, usually results from complications, or a concurrent illness. The most serious complications are involvement of the nose and throat, which accompanies the advance disease. Trophic ulcerations of the feet with secondary infection, osteomyelitis (bone infection), and lesions of the inner structures of the eyes, which leads to blindness.

The Treatment

Since 1941, a group of drugs, called sulfones, which are related chemically to sulfonamides, have been widely used in the treatment of leprosy. Sulfones are highly effective in the milder types. Although they do not cure the lepromatous types, serious complications are usually prevented.

Because the similarity of the bacillus which caused leprosy, the sulfones were also tested against tuberculosis, but without success. Sulfones do not destroy, but surpress the leprosy bacillus, so that the patient's own defenses slowly overcome the disease.

Treatment failures are observed in approximately 5% of the cases, resulting from the development of drug-resistance by the leprosy bacteria. Although the sulfones act slowly, no better agents have been developed for control of leprosy.

Leprosy is being treated today with large-scale outpatient treatment programs. The U.S. operates a specialized hospital for the treatment of leprosy at Carville, La., and maintains clinics at hospitals, in New Orleans and San Francisco. Also two institutions in the state of Hawaii, to conduct a continuous program for the care of patients, and the control of spread of the disease.

Source : Encyclopedia International

• Leprosy
  U.S. Public Health Service Hospital, Carville, Louisiana.
• Sulfones
  Harold C. Neu, M.D., Columbia University.

Bacterial Infections

Bacteria are important in the production of cheese, butter, yoghurt, sour cream, sauerkraut, pickles, and vinegar. Bacteria are used to process linen and to soften animal hides. Certain antibiotic drugs are obtained from bacteria. The important industrial solvents, acetone, and butyl alcohol are produced by bacterial fermentations.

The primitive microscopic organisms belonging to the lowest division of the plant kingdom, are widely distributed in nature. Bacteria are being found in soil, air, water, on plants and animals. Bacteria exist in environments where few other life forms can maintain themselves, such as hot springs where the temperature reaches 180 °F (82 °C), in the Antarctic Ocean, and in deep oceanic waters where they live under pressures of thousands of pounds per square inch.

Despite their extremely important role to other living organisms and the cycle of organic processes, they are also responsible for many plant, animal, and human diseases. Few events in the history of mankind have been as devastating as the Black Death, or bubonic plague, which swept through Europe in the 14th century (1348 to 1350), killing approximately 25 million people, 30–60 percent of Europe's population. Physicians have been identified a host of ailments as being caused by bacteria, including syphilis, typhoid fever, diphtheria, scarlet fever, diarrhea, and many other.

Exposure to pathogenic (disease-producing) bacteria doesn't guarantee that disease will result. This depends upon particular bacteria involved, the number of organisms that enter the body, and the ability of the body to fight the infection (immunity). Some bacteria are everyday inhabitants of the skin and the intestinal tract. As long as they remain confined to these places they are harmless, however, should they gain entrance to other parts of the body, they are capable of producing serious diseases. Infections of the kidneys (pyelonephiritis) or bladder (cystitis) are caused by bacteria that have escaped from intestinal tract.

Bacteria may produced the symptoms of disease through the effects of bacterial poisons (toxins). These substances may be secreted by the bacteria (exotoxins), or be built into the structure of the bacterial cell (endotoxins). The endotoxins are liberated only upon the death of the cell.

Bacteria are selective in the parts of the body that they choose to invade. The staphylococci infect the skin, producing boils and acne. The streptococci attack the throat. Tuberculosis and pneumonia are caused by organisms that settle in the lungs. Meningitis, an infections of the tissues surrounding the brain, is caused by various organisms, including the meningococcus, pneumococcus, streptococcus, and staphylococcus.

Bacterial endocarditis, bacterial infection of the lining of the heart, particularly of the heart valves. It usually appears in anyone who have previously had rheumatic or congenital heart disease. Treatment is with antibiotic drugs and depends upon the proper identification of the infecting bacteria. Penicilin-resistant organisms may be responsible in some cases and require special selection of antibiotics.

Diseases such as diptheria, tetanus, meningitis, and typhoid can be prevented by immunization, and many other bacterial diseases can be treated by antibiotic drugs. Tuberculosis patients must daily consume of antibiotic drugs for 6 month treatment. Most death from bacterial infections are caused by organisms that have become resistant to the action of antibiotics.

The Great Mortality: An Intimate History of the Black Death, the Most Devastating Plague of All Time by John Kelly

Source Encyclopedia International by :

• Jerard Hurwitz, Professor, Department of Development Biology and Cancer Research, Albert Einstein College of Medicine, New York.
• Jerome D. Waye, M.D., Assistant Clinical Professor of Medicine, Mount Sinai Medicine School; Chief, Division of Gastroenterology, Trafalgar Hospital, New York.
• Irving Solomon, M.D., Assistant Clinical Professor of Medicine, Mount Sinai Medicine School, New York.