Genotyping of methicillin-resistant Staphylococcus aureus isolates obtained in the Northeast region of Brazil

Methicillin-resistant Staphylococcus aureus (MRSA) is a major agent of hospital infections worldwide. In Brazil, a multiresistant MRSA lineage (ST239-SCCmecIIIA), the so-called Brazilian epidemic clone (BEC), has predominated in all regions. However, an increase in nosocomial infections caused by non-multiresistant MRSA clones has recently been observed. In the present study, 45 clinical isolates of MRSA obtained from a university hospital located in Natal city, Brazil, were identified by standard laboratory methods and molecularly characterized using staphylococcal chromosome cassette mec (SCCmec) typing and pulsed-field gel electrophoresis. Antimicrobial susceptibility testing was carried out using CLSI methods. The MRSA isolates studied displayed a total of 8 different pulsed-field gel electrophoresis patterns (types A to H) with predominance (73 percent) of pattern A (BEC-related). However, MRSA harboring SCCmec type IV were also identified, 3 (7 percent) of which were genetically related to the pediatric clone - USA800 (ST5-SCCmecIV). In addition, we found a considerable genetic diversity within BEC isolates. MRSA displaying SCCmecIV are frequently susceptible to the majority of non-β-lactam antibiotics. However, emergence of multiresistant variants of USA800 was detected.

Genotyping of methicillin-resistant Staphylococcus aureus isolates obtained in the Northeast region of Brazil.

Methicillin-resistant Staphylococcus aureus (MRSA) is a major agent of hospital infections worldwide. In Brazil, a multiresistant MRSA lineage (ST239-SCCmecIIIA), the so-called Brazilian epidemic clone (BEC), has predominated in all regions. However, an increase in nosocomial infections caused by non-multiresistant MRSA clones has recently been observed. In the present study, 45 clinical isolates of MRSA obtained from a university hospital located in Natal city, Brazil, were identified by standard laboratory methods and molecularly characterized using staphylococcal chromosome cassette mec (SCCmec) typing and pulsed-field gel electrophoresis. Antimicrobial susceptibility testing was carried out using CLSI methods. The MRSA isolates studied displayed a total of 8 different pulsed-field gel electrophoresis patterns (types A to H) with predominance (73%) of pattern A (BEC-related). However, MRSA harboring SCCmec type IV were also identified, 3 (7%) of which were genetically related to the pediatric clone--USA800 (ST5-SCCmecIV). In addition, we found a considerable genetic diversity within BEC isolates. MRSA displaying SCCmecIV are frequently susceptible to the majority of non-beta-lactam antibiotics. However, emergence of multiresistant variants of USA800 was detected.

Sorotipos de Streptococcus pneumoniae isolados de líquido cefalorraquidiano no período de 1977-1988 na cidade de Säo Paulo, Brasil / Serotypes of Streptococcus pneumoniae isolated from cerebrospinal fluid in 1977-1988 in Säo Paulo city, Brasil

Desde 1977, o Instituto Adolfo Lutz (IAL) vem promovendo a sorotipagem do S. pneumoniae ou pneumococo de infecçöes causadas por esta bactéria. As cepas isoladas têm sido encoaminhadas ao WHO Pneumococcal Reference Center, Pensilvania, E.U.A.. De 1977 a 1988, 1.000 cepas de pneumococo isoladas de LCR foram sorotipadas, de acordo com a nomenclatura dinamarquesa, e 60 sorotipos foram sorotipadas, de acordo com a nomenclatura dinamarquesa, e 60 sorotipos foram identificados. A maior freqüência foi do sorotipo 1, secundado por 6B, 18C, 14, 5, 3, 6A, 23F, 19F e 38. Estes sorotipos distribuídos segundo faixas etárias demonstraram incidência variável, notando-se uma certa peculiaridade, ou seja, a predominância do sorotipo 3 no grupo acima de 50 anos. Nos 12 anos considerados, 25 sorotipos apresentaram uma certa uniformidade na freqüência e o mesmo foi observado com relaçäo às estaçöes climáticas, apenas com um número maior de infecçöes meníngeas nos meses mais frios. Considerando a gravidade das infecçöes pneumocócicas notadamente as meningites, e a pouca informaçäo relativa aos sorotipos pneumocócicos que ocorrem na regiäo, julgamos importante essa informaçäo relativa aos sorotipos, uma vez que tem sido usadas, com sucesso, vacinas polissacarídicas na prevençäo dessas infecçöes

Bacteriological and epidemiological aspects of the diagnosis of Mycobacterium tuberculosis as the etiological agent of menigitis

Difficulties facing bacteriological diagnosis of meningitis are frequent, specially those caused by mycobacteria. From 1983 to 1987 samples of cerebrospinal fluid (CSF) from 16,921 patients mainly from the Emílio Ribas Hospital, SP, with clinical signs of meningitis were examined at the Instituto Adolfo Lutz, SP. 2,951 of the patients were diagnosed as being cases of bacterial meningitis, 134 of which tuberculous meningitis (4.5 per cent). 40.2 per cent were individuals of age 0-4 years, 52.3 per cent over 14 years and 7.5 per cent of unknown age. Tuberculous meningitis was clinically suspected in 51.5 per cent of the cases, while in the remaining cases (48.5 per cent) it was detected mainly because of the routine investigation of mycobacteria in CSF. Considering that the laboratory does not always receive a request to analyze M. tuberculosis in CSF and that, in terms of public health, tuberculosis is still an important problem, a careful study of mycobacteria in suspect cases of meningitis is recommended.