Low complement levels are seen in -

The glomerular lesions appear to result from deposition of immune complexes in the glomeruli. The evidence cited in suppo are as under: i) There is epidemiological evidence of preceding streptococcal sore throat or skin infection about 1-2 weeks prior to the attack. ii) The latent period between streptococcal infection and onset of clinical manifestations of the disease is compatible with the period required for building up of antibodies. iii) Streptococcal infection may be identified by culture or may be inferred from elevated titers of antibodies against streptococcal antigens. These include the following: anti-streptolysin O (ASO); anti-deoxyribonuclease B (anti-DNAse B); anti-streptokinase (ASKase); anti-nicotinyl adenine dinucleotidase (anti-NADase); and anti-hyaluronidase (AHase). iv) There is usually hypocomplementaemia indicating the involvement of complement in the glomerular deposits. v) It has also been possible to identify the antigenic component of streptococci which is a cytoplasmic antigen, Endostreptosin. Ref: Textbook of pathology. Harshmohan 6thediton page 665