OBJETIVOS: descrever resistência antimicrobiana e sorotipos de cepas de pneumococo. MÉTODOS: durante 57 meses, foi conduzida uma vigilância de cepas invasivas de pneumococo de pacientes com idade <20 anos. O pneumococo foi identificado pelos testes de solubilidade da bile e optoquina. A resistência à penicilina foi avaliada com o disco de oxacilina (1µg) e, para as cepas não suscetíveis, foi determinada a concentração inibitória mínima. Provas de difusão de disco e de microdiluição em placa foram utilizadas para avaliação da resistência a outros antimicrobianos. Reação de Neufeld-Quellung foi realizada para sorotipagem. RESULTADOS: dos 70 pacientes, 57,1% eram do sexo masculino. A mediana da idade foi 1,92 anos (média 3,19 ± 3,66 anos, variando de um mês a 19,5 anos), tendo 52,9% e 81,4% dos pacientes idade <2 anos e <5 anos, respectivamente. As cepas foram isoladas do sangue (91,4%), liquor (2,9%), líquidos pleural (2,9%), peritonial (1,4%) ou de abscesso (1,4%), de pacientes com pneumonia (77,1%), febre sem sinais localizatórios (10,0%), meningite (4,3%) e outros diagnósticos (8,6%). Resistência foi detectada à penicilina (20,0%), ao sulfametoxazol-trimetoprim (65,7%), à tetraciclina (21,4%), à ofloxacina (6,3%), à eritromicina (5,7%) e à clindamicina (2,9%). Não houve resistência ao cloranfenicol ou à vancomicina. Entre as cepas não suscetíveis à penicilina, resistência absoluta foi detectada em uma, a mesma que apresentou resistência intermediária à cefotaxima. Os sorotipos mais freqüentes foram: 14 (22,9%), 5 e 6A (10,0% cada), 6B e 19F (8,6% cada), 9V, 18C e 23F (5,7% cada). Das cepas resistentes à penicilina, 71,4% pertenciam ao sorotipo 14, 14,3% aos sorotipos 6B e 19F (cada). CONCLUSÕES: das 70 cepas, 67,2% têm sorotipos incluídos na vacina pneumocócica heptavalente conjugada, assim como estão incluídos todos os sorotipos que apresentaram resistência à penicilina.

OBJECTIVE: describe the antimicrobial resistance and serotype distribution of pneumococcal strains. METHODS: in a 57-month period, a laboratory-based surveillance of invasive pneumococcal strains from patients aged < 20 years was conducted. Pneumococcus was identified by means of tests for solubility in bile and optochin. Pneumococcal resistance to penicillin was screened by 1µg oxacillin disc and minimal inhibitory concentration was determined for the strains not susceptible to penicillin. Disc diffusion and broth microdilution methods were used for surveillance of resistance to other antimicrobials. Pneumococci were serotyped by means of the Neufeld-Quellung reactions. RESULTS: of 70 patients, 57.1% were males. The mean age was 1.92 yrs (mean 3.19 + 3.66 yrs, range 1 month to 19.5 yrs); 52.9% and 81.4% were < 2 yrs and < 5 yrs, respectively. The strains were isolated from blood (91.4%), CSF (2.9%), pleural (2.9%), peritoneal (1.4%) and abscess (1.4%) fluids from patients with pneumonia (77.1%), fever without localizing signs (10.0%), meningitis (4.3%), others (8.6%). Resistance was detected to penicillin (20.0%), trimethoprim-sulfamethoxazole (65.7%), tetracycline (21.4%), ofloxacin (6.3%), erythromycin (5.7%), clindamycin (2.9%). All tested strains were susceptible to chloramphenicol and vancomycin. Among penicillin-resistant strains, high resistance was detected in one, the same that showed intermediate resistance to cefotaxime. The most frequent serotypes were: 14 (22.9%), 5 and 6A (10.0% each), 6B and 19F (8.6% each), 9V, 18C and 23F (5.7% each). Resistance to penicillin was detected in serotypes 14 (71.4%), 6B and 19F (14.3% each). CONCLUSIONS: of 70 strains, 67.2% were classified as serotypes included in the heptavalent conjugate pneumococcal vaccine as well as were all penicillin-resistant strains.

Pneumonia is one of the leading causes of hospitalization and death among children in developing countries, and mortality due to pneumonia has been associated with S. pneumoniae infection. This investigation was designed to describe the antimicrobial susceptibility and serotype patterns of pneumococcal strains recovered from the blood of children with community-acquired pneumonia (CAP) and to assess the clinical findings of pneumococcal bacteremic patients with pneumonia. In a 26 month prospective study, blood cultures were obtained as often as possible from children (<16 years of age) diagnosed with CAP in two emergency rooms. Antimicrobial drug susceptibility tests and serotyping were performed when pneumococcus was identified. We studied 3,431 cases and cultured blood samples from 65.5% of those. Pneumococcus was recovered from 0.8% of the blood samples. The differences in age, somnolence, wheezing and hospitalization among children with and without pneumococcal bacteremia were statistically significant. Pneumococcal bacteremia was age-related (mean 1.63 ± 1.55; median 0.92) and associated with somnolence and hospitalization among children with CAP. One strain was recovered from pleural fluid. Penicillin resistance was detected in 21.0% (4/19) of the strains at an intermediate level, whereas 63.0% of the strains were resistant to trimethoprim-sulfamethoxazole. The most common serotypes were 14 and 6B, and these serotypes included the resistant strains. Eight of our 18 isolates from blood were of types included in the heptavalent conjugate pneumococcal vaccine, recently licensed in the USA.