Onchocerciasis in Ecuador: evolution of chorioretinopathy after amocarzine treatment

• Published in: British journal of ophthalmology Vol. 80; no. 4; pp. 337 - 342
• Main Authors: Cooper, P J, Proaño, R, Beltran, C, Anselmi, M, Guderian, R H
• Format: Journal Article
• Language: English
• Published: BMA House, Tavistock Square, London, WC1H 9JR BMJ Publishing Group Ltd 01-04-1996; BMJ; BMJ Publishing Group LTD
• Subjects: Adolescent; Adult; Age Distribution; Animals; Anthelmintics - therapeutic use; Antibiotics. Antiinfectious agents. Antiparasitic agents; Antiparasitic agents; Biological and medical sciences; Child; Child, Preschool; Cohort Studies; Ecuador - epidemiology; Humans; Incidence; Infant; Infant, Newborn; Medical sciences; Middle Aged; Onchocerca volvulus; Onchocerciasis, Ocular - drug therapy; Onchocerciasis, Ocular - epidemiology; Onchocerciasis, Ocular - prevention & control; Pharmacology. Drug treatments; Piperazines - therapeutic use; Prospective Studies; South America; Ecuador; America; Human; Skin disease; Retinopathy; Treatment efficiency; Uvea disease; Parasitosis; Helminthiasis; Onchocerciasis; Infection; Eye disease; Chemotherapy; Treatment; Nematode disease; Parasiticid; Filariosis; Chorioretinopathy
• ISSN: 0007-1161; 1468-2079
• DOI: 10.1136/bjo.80.4.337

AIMS: To investigate the impact of the macrofilaricidal drug, amocarzine, on the evolution of chorioretinopathy in onchocerciasis. METHODS: A prospective uncontrolled cohort study was performed using subjects infected with Onchocerca volvulus in a hyperendemic onchocerciasis focus in Esmeraldas Province in Ecuador. Study subjects were recruited into four cohorts in which ophthalmic and parasitological data were collected for 2, 3, 4, and 5 years respectively. RESULTS: Complete ophthalmic follow up was obtained for 294 individuals in the four cohorts. The incidence of retinal pigment epithelial atrophy tended to remain constant between cohorts while that of chorioretinal scarring with a greater observation period. The incidence rate of cases with new or extending chorioretinal lesions was greater with an increasing period of follow up. An association was seen between the cumulative microfilarial loads in the skin and the development of new chorioretinal lesions (p < 0.05). No relation was noted between cumulative microfilarial loads and the progression of existing disease. CONCLUSION: Amocarzine therapy did not prevent the natural evolution of chorioretinal disease. It was suggested that ocular microfilariae were necessary for the induction of chorioretinopathy in previously unaffected eyes and that extension of existing disease might also be related to the presence of ocular microfilariae or to other immunological mechanisms.