History
Travel to or residence in endemic countries is invariably part of the history in patients with dracunculiasis.
Recollection of ingestion of unfiltered or untreated water, ingestion of fresh fruits or vegetables washed with such water, or bathing or swimming in potentially contaminated water are all possibly elicited in the patient's history. The transmission of the disease has seasonal variation. In arid areas, the rainy season, with increased availability of surface water, coincides with most cases. In wet areas, the dry season, when sources of drinking water are limited, is associated with most cases.
History tends to be useful only to confirm the diagnosis after it has been presumed based on physical examination findings.
Physical Examination
A blister forms in the epidermis at a site chosen by the female worm, usually in the lower extremity. Immediately before blister formation, allergic-type symptoms, such as mild respiratory distress with wheezing, urticaria, periorbital edema, and pruritus, are often present. Patients may also be febrile during this period. With the emergence of the worm's head, the blister grows and becomes erythematous at its periphery. Edema occurs around the site, and inflammation of the papule causes further pruritus and burning pain. Usually, after a few days, but possibly as long as 2 weeks, the blister erupts, and the worm releases a collection of larvae-containing fluid. The swelling and pain often are markedly decreased after the blister is opened. At this point, an ulcer forms around the blister site as the adult worm continues to emerge.
Definitive diagnosis is made when the head of the worm is identified within the ulcer.
As noted, the ulcer tends to become secondarily infected.
No other particular physical findings are commonly noted, although some degree of lymphadenopathy may be found at any stage of the illness.
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A method used to extract a guinea worm from the leg vein of a human patient.
