Cryoglobulins in Schistosoma haematobium infection.

The sera of school children with Schistosoma haematobium infection were tested for the presence of cold-insoluble immune complexes "the cryoglobulins". Two different methods were used: the standard macro-technique and the micro-adaptation technique. On using the standard macro-technique, 40 (32.8%) out of 122 schistosomiasis patients and 6 (7.5%) out of 80 control children were positive for cryoglobulins. Using the micro-adaptation technique, the corresponding numbers were 47 (38.5%) and 8 (10%), respectively. A comprehensive medical examination was carried out before treatment. After treatment with metrifonate (Bilarcil) the quantity of cryoglobulins and the number of children with cryoglobulins were significantly reduced to 12 (9.8%) when using macro-technique, and to 15 (12.3%) with micro-adaptation technique, thus suggesting a possible relationship of cryoglobulinaemia with urinary schistosomiasis. There was a significant difference in the number of sera found positive by the two techniques (X2 = 0.875, P less than 0.1).

Schistosoma haematobium in Ajara community of Badagry, Nigeria. A study on prevalence, intensity and morbidity from infection among primary school children.

A prevalence, intensity and morbidity study was carried out at a primary school amongst 681 pupils aged 6-15 years. A comprehensive medical examination including urinalysis was carried out. Attendance at school and average grades scored during the preceding schoolyear were used as crude indiced of performance. The overall prevalence rate was 24%. The mean egg count was 435 ova/10 ml urine in infected children. Haematuria was observed in 65% of infected children with the greatest intensity in patients with the highest egg count. Both the haematocrit (PCV) and haemoglobin concentrations bore no relationship to the intensity of infection; whilst there was a direct relationship between the level of proteinuria and the number of ova excreted. Proteinuria of more than 100 mg/100 ml was found in 54% of subjects and in 23% of these it was 300 mg/100 ml. Anthropometric measurements were not related to intensity of infection nor were attendance and the average scored during the preceding schoolyear. It is concluded that probably only minimal morbidity is associated with S. haematobium infection in this area; this may be explained by the relatively low intensity of infection including acquired immunity and the seasonal pattern of transmission.

Schistosoma haematobium in Ajara community of Badagry. Metrifonate trials in the treatment of the disease.

Metrifonate, an organophosphorus cholinesterase inhibitor, which has been shown to be effective in the treatment of urinary schistosomiasis was administered orally to 145 school children aged 6-15 years at a dose of 10 mg/kg body weight in 3 doses at 14-day intervals. Urinalysis was carried out to determine egg out-put, haematuria and proteinuria. None of the subjects was anaemic before treatment, 78.6% tolerated the drug well while 21.4% had minimal and transient side-effects. 47.6% with light infections, 29.9% with moderate infections and 5.1% with heavy infections, had no ova of S. haematobium in their urine after the first dose. The pre- and post-treatment urinalysis showed very significant reductions in the number of subjects with haematuria and proteinuria. However, some of those with no ova of S. haematobium in their urine still had haematuria and proteinuria. The determination of these parameters indicates the intensity of infection and can be used in assessing the results of chemotherapy.

Correlation of Plasmodium falciparum gametocytemia with complement component titers in rural Nigerian school children.

The relationship between Plasmodium falciparum gametocytemia and the complement components C3, C4, and C3b was investigated in 141 ambulant rural Nigerian school children. Three groups were studied. Group 1 included 42 children with circulating P. falciparum gametocytemia in which the mean titers of C3, C4, and C3b were 145.4 +/- 22.6 mg/100 ml (72%), 60.5 +/- 0.2 mg/100 ml (149%), and 64.0 +/- 5.9 mg/liter (65%), respectively. These findings indicated marked C3b hypocomplementemia. Group 2 included 50 children who were used as controls and lacked malaria parasitemia. C3, C4, and C3b mean titers were 161.6 +/- 28.9 mg/100 ml (80%), 56.8 +/- 2.07 mg/100 ml (140%), and 84.8 +/- 11.4 mg/liter (86%), respectively. Group 3 included 49 children with other blood stages of P. falciparum parasitemia but no gametocytes. C3, C4, and C3b mean titers in this group were 103.0 mg/100 ml (51%), 18.3 +/- 1.2 mg/100 ml (45%), and 90.7 mg/liter (92%), respectively. Our findings suggest that C3b hypocomplementemia may be related to the advent of circulating P. falciparum gametocytes in children. We also confirmed C3 and C4 hypocomplementemia in acute human malaria. The implication of our findings in relation to neat in vitro culture of P. falciparum gametocytes or total inhibition of gametocytogenesis in malaria control is still speculative.

Cellular immunity in patients with meningococcal disease and in vaccinated subjects.

Cell-mediated immunity was studied in patients with group A meningococcal meningitis and in normal subjects given group A meningococcal vaccine. Lymphocytes responsiveness to phytohaemagglutinin and to meningococcal antigens was markedly depressed in patients with acute meningococcal infection. This defect was present when lymphocytes were cultured in autologous or foetal calf serum. Patients also showed a transient increase in the degree of inhibition produced by whole group A meningococci in leucocyte migration assays. Meningococci of other groups produced a similar degree of inhibition. Vaccination with group A meningococcal polysaccharide vaccine had no effect on lymphocytes responsiveness to meningococcal antigens or on the inhibitory effect of group A meningococci on leucocyte migration.

Acute phase proteins in children with protein-calorie malnutrition.

The serum concentrations of the acute phase proteins, C-reactive protein, caeruloplasmin and haptoglobin were significantly higher in children with protein-calorie malnutrition than in age-matched controls, while the concentrations of alpha1 antitrypsin, alpha2 macroglobulin, transferrin and complement component C3 were significantly lower. During rehabilitation and treatment with antibiotics, C-reactive protein disappeared from the serum in most of the patients whilst the levels of caeruloplasmin and haptoglobin returned to normal values. On the other hand the serum concentration of alpha1 antitrypsin, alpha2 macroglobulin, transferrin and C3 showed significant increases. It is suggested that C-reactive protein and haptoglobin may provide useful indices of the presence or absence of infection in children with malnutrition.