Immune responses directed against microfilariae correlate with severity of clinical onchodermatitis and treatment history.
The induction of pathological changes in Onchocerca volvulus infections is directly related to the presence of the microfilarial stage of this filarial nematode. Patients with either of the 2 major forms of the clinical disease (i.e., asymptomatic/mild [n=12] and severe [n=16] dermatopathology) were studied. The cellular immune responses (cell proliferation) of those with severe disease were stronger (stimulation index [SI], 12.3+/-1.9) than those with mild dermatopathological effects (SI, 2.9+/-0.6) or control patients (SI, 4.5+/-0.4). Cytoadherence antibody responses were greatest (grade 4) in the clinically severe group and only weak (grades < or = 1) in the mild group or the control patients. Ivermectin treatment was followed by an increase in immune responsiveness in those with initially poor responses. Thus, the degree of dermatopathological effect is related to the host's immune response against microfilariae, and ivermectin augments such responses.
Ali
Magdi M
MM
Tropical Medicine Research Institute, University of Khartoum, Sudan. alimagdi@msu.edu
Baraka
Omer Z
OZ
AbdelRahman
Suzan I
SI
Sulaiman
Suad M
SM
Williams
Jeffrey F
JF
Homeida
Mamoun M
MM
Mackenzie
Charles D
CD
D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D000977:Antiparasitic Agents; D018450:Disease Progression; D006801:Humans; D007559:Ivermectin / Q000627:therapeutic use*; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000276:immunology; D008842:Microfilariae / Q000302:isolation & purification; D017181:Onchocerca volvulus / Q000276:immunology* / Q000302:isolation & purification; D009855:Onchocerciasis / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology*; D012867:Skin / Q000469:parasitology; D012876:Skin Diseases, Parasitic / Q000175:diagnosis / Q000276:immunology*
D000871:Anthelmintics; D000977:Antiparasitic Agents; D007559:Ivermectin