Enzymes and proteins in tropical diseases

Abstract

Various parameters were measured for two control groups; the African Medical students and the matched controls for the disease Endomyocardial Fibrosis (EMF). Many differences were observed in these two populations, attributable perhaps to the environments these groups are exposed to: e students live in a healthier environment and are on a balanced diet unlike the local population. The results form the control groups were used to compare the data obtained for the diseased groups studied: EMF and the related disorder Rhematic Heart Disease (RHD). 1. Serum Proteins: Significantly lower total protein and

albuminj levels were observed in the matched control group as compared to the Student group. The y-globulin level was similar in the two groups. When compared with the matched controls, the EMF group revealed higher total protein and Y- globulin but low albumin levels. This raised y-globulin level suggests that an immunological factor is involved in EMF. RHD group sh~d similar pattern to EMF. The follow up studies did not reveal any consistent changes in serum protein patterns as the disease progressed. 2. Immunoglobulins. High IgG level was observed in the matched controls as compared to the student group. IgA and IgM levels were similar.The higher IgG level in the matched controls could be because of the more frequent exposure of this group to antigenic stimulation by fungal,viral and bacterial infections. Higher IgM levels were observed in both EMF and RHD groups as compared to the matched controls, again suggesting an abnormal immunological response in EMF Que to IgM

antibodies. This is an important observation because malarial antibodies have been located in IgM immunoglobulins. Hence the etiology of EMF may be related to malaria. The IgM level was not significantly different in EMF and RHD groups; the two disorders are therefore similar in their immunological response. Tribal analysis of the patients with high IgG and Igm levels indicated that mostly the immigrant populations fell in this group. The follow up study of the patients revealed a gradual decrease in IgM as the disease progressed. 3. Lactate dehydrogenase (LDH) No significant differences were observed in total LDH or HBDH levels in the two control groups. However, lower LDH-1 and higher LDH-4 and LDH-5 were observed in the control group as compared to the student control. When compared with the matched controls, the EMF group showed higher LDH-1 and similar LDH-2 levels but lower LDH-3 and LDH-4 levels. LDH-5 was usually not detected in the EMF patients. This isoenzyme pattern shows a shift of towards the cardiac tissue pattern and hence demonstrates the presence of cardiac muscle damage in EMF. Significantly lower LDH-1 level was observed in RHD as compared to EMF suggesting greater myocardial damage in EMF. No myocardial involvement could be shown in either pyomyositis or parotid abscess patients.The total LDH levels in the ofrmer group were higher than the latter but similar to the EMF group. Follow up studies showed a gradual decrease in LDH activity as the disease progressed. In some patients a gradual decrease in LDH-1 and LDH-2 was also observed. 4. Glucose-6.phospaate dehldrogenase (G6PDH) and sickle cell haemoglobin (HbS). The samples studied for these two parameters were small, hence not much information was obtained from these. Raised G6PDH levels were obtained for both the EMF and the RHD groups. Similar incidence of enzyme deficiency was observed in the student, the matched control and EMF groups No enzyme deficiency was obtained in the RHD group. The incidence of sickle cell trait was again similar in the student, the matched control and the EMF groups RHD group had a high incidence of the trait.