Serum antibodies to group A streptococcal extracellular and cell-associated antigens in Egyptians with post-streptococcal diseases.

We investigated serum antibodies to a comprehensive array of group A streptococcal antigens and superantigens in Egyptian subjects. Antibodies to Streptococcus pyogenes cell-associated proteins and to proteins released by rapidly dividing S. pyogenes were compared in four patient groups with different post-streptococcal diseases and in healthy controls. Enzyme-linked immunosorbent assays showed that total Ig and IgG to extracellular antigens were significantly higher in patients with acute rheumatic fever (ARF) compared to healthy controls, but no differences were found in either total Ig or IgG titres to cell-associated proteins between any of the groups. Western blotting showed that multiple extracellular and cell-associated antigens, covering a wide range of molecular masses, were recognised by all sera, including healthy controls. No evidence was obtained for putative dominant antigens associated with any disease group, although a low molecular mass cell-associated protein (approximately 4 kDa) was clearly recognised by two-thirds of subjects irrespective of disease status. These findings demonstrate that raised serum Ig and IgG titres to extracellular, but not cell-associated, S. pyogenes antigens are a feature of ARF in this population, and suggest that multiple S. pyogenes antigens contribute to this response.

Schistosomiasis and inflammatory polyarthritis: a clinical, radiological and laboratory study of 96 patients infected by S. mansoni with particular reference to the diarthrodial joint.

Patients with active Schistosoma mansoni infection attending a medical clinic in an endemic area, 100 miles from Cairo, were asked to participate in this study. Ninety-six patients are reported, 72 of whom presented with musculoskeletal complaints. Nine of these presented with an enthesitis alone; 16 had an inflammatory peripheral polyarthritis alone; the remaining 47 were suffering from the combination of both an arthritis and an enthesitis. Alpha-1-acid glycoprotein was significantly lowered in those patients with musculoskeletal manifestations.