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(trĭk-ăl′jē-ă) Pain caused by touching or moving the hair.


(trĭk-ī′ă-sĭs) [Gr. thrix, hair, + -iasis, condition] Inversion of eyelashes so that they rub against the cornea, causing a continual irritation of the eyeball. Symptoms are photophobia, lacrimation, and feeling of a foreign body in the eye. The condition is treated by cryotherapy, epilation, electrolysis, and operation, such as correcting the underlying entropion with which this condition is usually associated.


(trĭk″ĭ-lĕm-ō′mă) A benign tumor of the outer root sheath epithelium of a hair follicle.


(trĭk-ī′nă) [Gr. trichinos, of hair] Trichinella.


(trĭ-kī′nă) pl. trichinae A larval worm of the genus Trichinella.


(trik″ĭ-nel′ă) A genus of nematode worms belonging to the order Trichurida and the family Trichinellidae. They are parasitic in humans, hogs, rats, and many other mammals.

T. spiralis The species of Trichinella that commonly infests humans, causing trichinosis. Infection occurs when raw or improperly cooked meat, particularly pork and wild game, containing cysts is eaten. Larvae excyst in the duodenum and invade the mucosa of the small intestine, becoming adults in 5 to 7 days. After fertilization, each female deposits 1000 to 2000 larvae, which enter the blood or lymph vessels and circulate to various parts of the body where they encyst, esp. in striated muscle.


(trĭk″ĭ-nĕl-lō′sĭs) [Gr. trichinos, of hair, + osis, condition] Trichinosis.


(trik″ĭ-nō′sĭs) [trichin(a) + -osis] Infection by the roundworm parasite Trichinella spiralis, resulting from consumption of undercooked pork or wild game containing T. spiralis cysts. SYN: trichinellosis.

INCIDENCE: In the U.S., less than 0.5% of pigs are infected, and less than 40 cases of the disease are now reported annually, although trichinosis continues to be common throughout the world.

CAUSES: Gastric juices release the worms from their cysts, which quickly reach sexual maturity. The female roundworms then burrow into the intestinal mucosae of organisms and produce larvae in the gastrointestinal tract that move through the bloodstream and lymphatic system and encyst in striated muscle tissue (chest, diaphragm, arms and legs), where they die.

SYMPTOMS AND SIGNS: Anorexia, nausea, vomiting, abdominal cramping, and diarrhea may sometimes be present when the infected meat is eaten (invasion or stage 1). After the larvae penetrate the intestinal mucosa and invade blood and lymph to migrate to the muscles (dissemination or stage 2), patients have fever, muscle pain (most often in the extremities), and periorbital and facial edema. Sometimes patients experience itching and burning of the skin, sweating, and skin lesions. Rarely, signs of encephalitis, myocarditis, and ...

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