Production of BRO β-Lactamases and Resistance to Complement in European Moraxella catarrhalis Isolates

Of the 419 Moraxella catarrhalis isolates collected during the 1997-1999 European SENTRY surveillance study, 385 (92%) were β-lactamase positive. Twenty-two (5.7%) produced BRO-2 β-lactamase. Twenty-one new mutations were found in the putative promoter region of the bro genes. Nineteen percent of all isolates tested were complement sensitive. Resistance to β-lactams is not linked to the phylogenetic lineages associated with susceptibility to complement.