FURUNCULAR CUTANEOUS MYIASIS CAUSED BY DERMATOBIA HOMINIS LARVAE EOLLOWING TRAVEL TO BRAZIL

Abstract

A 62‐year‐old Japanese man had visited Rondonia in central Brazii on May 28, 1994, at which time he suffered insect bites on the left axiila and ieft chest regions. Three bites persisted and became tender and painfui. These areas developed into tender nodules with moderate serous drainage from a central pore. Malaise and an intermediate‐grade fever accompanied the eruption. The tender nodules continued after he returned to Japan on July 7. The diagnosis of furunculosis was made by his family physician, but treatment with oral cefdinir (300 mg per day) and naproxen (600 mg per day) for 2 days and application of ointment containing 0.1% gentamicin sulfate failed to resolve the lesions. The patient complained of a crawling sensation under the skin. Since a maggot was removed from the axillary lesion with the aid of the patient's fingers, he was referred to the Dermatology Clinic of the Kurume University Hospital on August 1, for evaluation of parasitic diseases.Physical examination revealed two firm furuncle‐like erythematous nodules, 2.0 cm in diameter, with a centrally placed 4 mm punctum on the left side of the chest (Fig. 1). There was serous drainage from each punctum and a motile larva was seen in each cavity. A lesion on the axilla had healed spontaneously. Laboratory tests were normal. Two florid lesions on the chest were surgically removed under local anesthesia with 0.5% lidocaine hydrochloride. Histologic examination revealed a mixed cell inflammatory infiltrate throughout the dermis with a tract containing a larva. Examination of the larva revealed a segmented ovoid organism, 1.5 × 0.5 cm in size (Fig. 2). The lesions healed completely within 2 weeks without further treatment. The larva removed by the patient was forwarded to the Department of Medical Zoology, Faculty of Medicine, Tokyo Medical and Dental University, and was identified as third instar larvae of Dermatobia hominis, the human botfly. The other two of the third instar larvae were transplanted under the skin of a rat and a mouse to obtain pupae or adults, but they failed to pupate and died.