Clinical and nasopharyngeal isolates of unusual multiply resistant pneumococci
K. P. Klugman, H. J. Koornhof and V. Kuhnle
Routine surveillance of pneumococcal isolates for resistance to antibiotics
has revealed the emergence of an unusual pattern of multiple antimicrobial
resistance in South Africa. Thirty-nine pneumococcal isolates, including 21
from clinical specimens, showed resistance to tetracycline, erythromycin,
clindamycin, trimethoprim, and a combination product of trimethoprim and
sulfamethoxazole sodium (co-trimoxazole), yet susceptibility to penicillin
G. Multiple resistance has to date been almost invariably associated with
resistance to beta-lactam antibiotics. A survey of nasopharyngeal carriage
revealed carriage of an additional 21 isolates of multiply resistant
pneumococci, representing 7.9% of children investigated in Johannesburg,
but these organisms were not found in children in Soweto or four rural
villages. We present the minimum inhibitory concentrations of 15
antimicrobial agents against 15 of these 21 strains. These findings are
discussed in relation to exposure of these populations to antibiotics and
to the treatment of local and systemic pneumococcal disease. Of all 60
isolates of multiply resistant pneumococci isolated to date, those fully
characterized serologically belong to serotypes 6B, 14, or 19F.
