Cases

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Answer Dracunculiasis, or guinea worm disease in humans, resulting from infection with Dracunculus medinensis: The mammogram shows a coiled, whorled-type calcification in the subcutaneous tissues characteristic of a dead guinea worm. In humans, dracunculiasis, or guinea worm disease, results from infection with D medinensis. In 1986, more than 2.25 million cases of dracunculiasis occurred worldwide. Ten years later, the estimated worldwide incidence was close to 152,000 cases, which were mostly from Sudan. This decline has been a result of the Global Dracunculiasis Eradication Campaign. Dracunculiasis now occurs in only 13 countries in Africa, the Middle East, and in South Asia, including Nigeria, Cameroon, Ghana, Sudan, India, and Pakistan. Infected areas in Africa lie in a band between the Sahara and the equator. People contract guinea worm disease by drinking fresh water contaminated with D medinensis larvae. Small water fleas in the water swallow the larvae. After the worms mature in the flea, any person who swallows contaminated water becomes infected. Once inside the body, stomach acid digests the water flea but not the guinea worm. During the next year, the worm grows to full adult size. After a year, the worm migrates to the surface of the body into the subcutaneous tissue. As it migrates, a blister develops on the skin, where the worm resides. The female adult worm eventually emerges from the blister, rupturing the skin. When hosts step into water, they release a milky, white liquid containing millions of immature larvae, contaminating the water supply. Most worms appear on the legs and feet, but they may occur anywhere in the body, as cases in the arms, breasts, head, back, and scrotum are well documented. Morbidity is from secondary infection of the lesions and from the severe, incapacitating pain associated with the blisters, especially when the worms exit the body. The live guinea worm is not identified radiologically except in rare instances when iodinated contrast medium is injected into the body of the worm to delineate its full extent. However, after it dies, the guinea worm may undergo calcification from cell secretion or necrotic cellular debris. The female D medinensis worm appears as a long, stringlike, serpiginous calcification. The calcification is frequently segmented and beaded as muscle movements breaks up the worm. If the worm is in the breast, the calcifications may be intramammary, in and around the ducts, in the lobules, in vascular structures, in interlobular connective tissue, or in the fat. They may also be found in the skin in the subcutaneous tissue. They can appear with or without an associated lesion, and their morphologies and distributions provide clues to their etiology and their association with a benign or malignant process. The incidence of breast calcification from guinea worm infection is difficult to assess because the disease is rare outside endemic areas and parts of Africa, where it is common. Cases are usually rural and not well documented. However, the breast is probably a relatively rare site of presentation. Of interest, the universal symbol of medicine, ie, the Asklepion (or caduceus, after Asklepios, the Greek god of healing and medicine) is likely a representation of dracunculiasis and its treatment. To this day, accepted treatment remains the same. The adult guinea worm is wrapped around a stick a few centimeters a day to coax it from a person's skin. Removal of the entire worm may take days to weeks. Metronidazole or thiabendazole may be used as an adjunct to stick therapy. The worm may also be removed surgically if facilities are available. Diagnosis of dracunculiasis outside of endemic areas requires consultation with an infectious disease specialist and epidemiologic investigation to prevent additional cases. For more information, see the eMedicine article Dracunculiasis (within the Pediatrics specialty).