Subcutaneous nodules as a manifestation of onchocerciasis. A rare condition in the United States
J. M. Palomar, D. M. Bray 3rd, F. W. Grannis and P. C. Beaver
Although infection with tissue nematodes is a significant health problem in
many parts of the world, such cases are unusual in the continental United
States. This report describes a case of Onchocerca volvulus infection,
acquired by a 38-year-old female missionary in northern Brazil, that
manifested as subcutaneous nodules in the groin and flank two years after
the patient's return to the United States. A year previously, a wrong
diagnosis of Wuchereria bancrofti was made at biopsy. At that time,
treatment with diethylcarbamazine citrate had to be discontinued because of
intense pruritus. Examination of a wet saline impression smear of a new
biopsy specimen showed the adult worms to have regularly arranged outer
annular ridges, which, together with the pruritus after treatment with
diethylcarbamazine (a positive Mazzotti test), led to the diagnosis of
onchocerciasis. Retreatment with diethylcarbamazine again caused pruritus,
but this was tolerated as were subsequent treatments.