Dermatological problems of onchocerciasis in Nebbi District, Uganda

A cross-sectional survey of 770 subjects in onchocerciasis hyperendemic villages and 223 subjects from a control community in Nebbi District in the West Nile region of Uganda revealed a high prevalence of onchocercal skin disease of 48% in endemic villages. The most common skin problem was troublesome itching (40%); and the prevalent skin lesions were chronic papular onchodermatitis (16%), depigmentation (4%), lichenified onchodermatitis (2%) and acute papular onchodermatitis (1%). Other typical varieties of onchocercal skin diseases such as, hanging groin, lymphoedema and marked lymphadenopathy were infrequent, and considered rare. Pityriasis vergicolor was the most common non-onchocercal skin lesion in both control and endemic communities, accounting for 37% of all non-onchocercal skin lesions. These skin lesions were associated with a variety of psycho-social and economic impact; and there was a positive correlation between the prevalence of troublesome itching and the prevalence of modules (correlation coefficient r = 0.62, p = 0.00). Given the prospects of onchocerciasis control based on mass ivermectin distribution in communities where blindness is common, we recommend that treatment be extended to communities where blindness is less common, but skin disease known to be predominant.