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Urticaria

Urticaria can drive you crazy. This maddening skin condition causes a dark red, raised, bumpy, skin rash that itches with a vengeance. A more common name for urticaria is hives.

The acute form of urticaria lasts less than six weeks and is almost always the result of an allergy while the chronic form, lasting longer than six weeks, is usually a symptom of an underlying medical condition. About 35% of patients with chronic urticaria also have an autoimmune disorder.

Another form of acute urticaria is caused by a virus but temperature extremes, sunlight, exercise, friction, or a change in air pressure can trigger an outbreak, too.

The best treatment methods depend upon the source of the condition.

Vitiligo

Vitiligo is a chronic skin condition that causes the skin to lose its natural color. The disorder usually begins in young adulthood, producing pale, irregularly shaped patches of skin that are often symmetrically located on the body.

Little is known about the cause of vitiligo but it’s usually thought to be caused by genetic or environmental factors or an autoimmune disorder. Less than 2% of the world population is thought to have vitiligo.

This disorder is so rare that it was virtually unknown until Michael Jackson announced in 1993 that he had vitiligo. His diagnosis came in 1986 but he didn’t disclose it publicly until tabloids accused him of cosmetically bleaching his skin.

Domesticated animals can get vitiligo, too, with Arabian horses and Rottweiler dogs most likely to develop it. In rare cases, the animal develops a constant itch as a result of the disorder.

West Nile Virus

The West Nile virus, found in both temperate and tropical climates, is most often carried by mosquitoes, infecting the people or animals they bite. Birds are the most common carriers of the virus but dogs, cats, horses, rabbits, squirrels, skunks, chipmunks, and bats carry it, too.

Most people produce no symptoms of illness when exposed to the West Nile virus but others develop flu-like symptoms (fever, chills, headache, sweating, muscular and joint pain and weakness, swollen lymph nodes, skin rash, and gastrointestinal symptoms) that are generally mild and last 7 to 10 days.

A more severe, neuroinvasive, form of West Nile Fever causes meningitis and encephalitis, which can produce coma-like symptoms and require many months for recovery. Of every 141 people infected with the virus, 110 will exhibit no symptoms of infection, 30 will develop the mild form of West Nile Fever, and one will develop the neuroinvasive form of illness.

The current crisis in the home mortgage industry has had a direct effect on the West Nile virus in California, where backyard swimming pools are common. As people must decrease spending to save their homes, they often neglect their backyards, including their pools. When foreclosure claims a home, no one maintains the pool. These many small bodies of stagnant water have dramatically increased the mosquito population and the incidence of West Nile fever has grown accordingly.

Xerophthalmia

A deficiency in vitamin A can lead to a medical condition known as xerophthalmia, or dry eyes in Greek. Rare in the industrial world, xerophthalmia is common where dietary deficiencies are common.

If left untreated, corneal ulceration and eventual blindness can occur. A long-term absence of tears to lubricate the eye can cause the conjunctiva to become dry, wrinkled, and thick. The conjunctiva is the mucus membrane that lines the inner surface of the eyelid and the outer surface of the eyeball.

While vitamin A deficiency is the most common form of xerophthalmia, other factors, including the aging process, autoimmune diseases, scarring of the conjunctiva, and an inability to close the eyelid entirely, can cause the condition.

Yusho Disease

Contamination from polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs) in 1968 led to an outbreak of Yusho disease in Kyoto, Japan, that affected humans and poultry-industry birds. This outbreak of Yusho disease, which means oil disease, was actually a mass poisoning of rice bran oil contaminated by the industrial chemicals.

In 1968 Kyoto, 400,000 birds died from respiratory distress caused by eating contaminated rice bran and 14,000 people became sick with skin and eye lesions, coughing, headaches, fatigue, compromised immune response, and irregular menstrual cycles. Children exposed to the contaminants also suffered poor cognitive development.

A similar outbreak occurred in Taiwan in 1979, where the illness was named Yu-Cheng disease, and in Ireland in 2008 when dioxin contamination in the pork industry led to a crisis requiring worldwide recall of all Irish pork products.

Zollinger-Ellison Syndrome

When Zollinger-Ellison syndrome is present, the stomach produces too much hydrochloric acid. The hormone, gastrin, regulates hydrochloric acid production and disorders that increase the secretion of gastrin affect acid levels. About 95% of all patients with peptic ulcers secrete excess gastrin.

Zollinger-Ellison syndrome is a common symptom of tumors in the pancreas or duodenum. As many as two-thirds of all such tumors are malignant and frequently spread to the liver, lymph nodes, and the pituitary and parathyroid glands.

Abdominal pain and diarrhea are symptoms of Zollinger-Ellison syndrome, as are severe ulcerations of the stomach and small bowel when no other symptoms are apparent.

Laboratory tests and imaging scans can detect Zollinger-Ellison syndrome and it can be treated with medications that reduce acid secretion. When tumors are present, chemotherapy or surgery should be used to remove them.

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