Hereditary complement deficiency in survivors of meningococcal disease: high prevalence of C7/C8 deficiency in Sephardic (Moroccan) Jews.

The prevalence of complement deficiency was studied among 111 survivors of sporadic meningococcal disease located through the medical records of 10 Israeli hospitals. There were 11 patients with CH50 = 0: one with systemic lupus erythematosus and 10 with hereditary terminal complement deficiency (four with homozygous C7 and six with C8 deficiency). There was no hereditary complement deficiency among 39 Ashkenazi subjects as against 18 per cent among 38 Sephardi subjects and 40 per cent among 15 of Moroccan ancestry (p less than 0.05). The age at first presentation of meningococcal disease in complement deficient patients was 14.7 +/- 7.6, years compared with 8.1 +/- 10.9 in the non-deficient patients (p less than 0.025). None of the complement deficient patients had meningitis below the age of 5 years vs. 49 per cent of non-deficient subjects. Recurrent meningitis was observed in 40 vs. 4 per cent (p less than 0.01) and meningitis in siblings in 40 vs. 2 per cent respectively (p less than 0.001). In addition to the 10 propositi, 11 non-propositus siblings were identified with severe complement deficiency (six with homozygous C7 and five with C8 deficiency). Seven of the non-propositi had no history at all of meningitis or any other serious systemic disease, underlining the relatively favourable prognosis of terminal complement deficiency. With increasing familiarity with the clinical features of this hereditary disease, it is possible now to identify on clinical grounds patients with meningococcal disease with a high likelihood of terminal complement deficiency.