Degranulated eosinophils, eosinophil granule basic proteins and humoral factors in Nigerians with endomyocardial fibrosis
Urhoghide, G.E.; Falase, A.O.
African Journal of Medicine and Medical Sciences 16(3): 133-139
1987
ISSN/ISBN: 0309-3913 PMID: 2829606 Document Number: 297708
The frequency of eosinophilia, degranulated eosinophils, and raised serum levels of eosinophil granule basic proteins was determined in ten Nigerians with EMF and fifteen normal controls matched for age and sex, and from the same enviroment and social background as the patients. Sera from the patients and control subjects were also examined for autoantibodies, immune complexes, filaria antibodies and immunoglobulins. A mild eosinophilia was observed in four of the patients. The mean direct eosinophil count in the patients (0.407 .+-. 0.14 .times. 109/l) was, however, not significantly different from that of the control subjects (0.399 .+-. 0.07 .times. 109/l). Degranulated eosinophils were absent in the blood and bone marrow aspirates of the patients, and peripheral blood of the controls. It was also found that the mean concentration of eosinophil granule basic proteins (ECP/EPX) in the patients (0.278 .+-. 0.1 .mu.g/ml) was not significantly different from the mean value for the control subjects (0.371 .+-. 0.1 .mu.g/ml, P > 0.5). Serological studies using Brugia pahangi antigens failed to demonstrate filaria antibodies in the patients and the control subjects. Microfilaria were also absent in their peripheral blood films. Using the indirect immunofluorescent technique, anti-heart anti-bodies were not demonstrated in the sera of the EMF patients and control subjects. Five (50%) of the patients and four (30.7%) of the normal controls had immune complexes levels far in excess of the upper limit of normal. However, the mean concentration of immune complexes in the patients (16.35%) was not significantly different from the value for control subjects (12.13%, P > 0.5). The mean concentrations of IgG and IgA (28.7 .+-. 3.9 and 2.8 .+-. 0.8 gm/l, respectively) in the patients were significantly higher than the mean values (19.5 .+-. 0.6 and 2.3 .+-. 0.2 g/l, respectively; P < 0.05) for the controls. These findings are similar to those recently reported in dilated cardiomyopathy(DCM) and rheumatic heart disease (RHD), and seem to supplement the increasing clinical evidence that EMF, DCM and RHD may be sequel to infection. It is concluded that degranulated eosinophils and significantly elevated serum levels of eosinophil granule basic proteins are not present in EMF seen in Ibadan, Nigeria. Eosinophilia is as common in the controls as in the patients. This study has shown no significant role for humoral immunity in the mechanism of cardiac damage in EMF.