Association of furunculosis and familial deficiency of mannose-binding lectin

Background Polymorphisms in the mannose-binding lectin gene reduce serum mannose-binding lectin levels and are associated with enhanced risk of infection. In a family with recurrent staphylococcal disease presenting as furunculosis or carbuncles, an association with mannose-binding lectin deficiency was investigated. Materials and methods Levels of functional mannose-binding lectin were estimated and the genotypes of the mannose-binding lectin gene were analysed on blood samples, collected from the members of one particular family with a high prevalence of furunculosis. Results Functional mannose-binding lectin levels in sera of 13 of the 28 members of one family showed deficiency. Furunculosis or carbuncles appeared to be present in nine of the 28 family members, seven of which showing the pBly allele and mannose-binding lectin deficiency. Four young family members of the second generation were pBly positive and mannose-binding lectin deficient, but had not shown furunculosis yet. Conclusion Members of a particular family suffering from furunculosis differ from their 'healthy' relatives as to mannose-binding lectin genotypes, indicating the relevance of normal mannose-binding lectin levels in the defence against staphylococcal disease.