[Pneumococcal bacteremia in adult patients at a hospital in Madrid: serotypes and susceptibility].
BACKGROUND
The aim of this study is to describe the distribution of Streptococcus pneumoniae serotypes, its antimicrobial susceptibility profiles and the relation with vaccines in pneumococcal invasive strains isolated from blood cultures of adult patients.


METHODS
All pneumococci isolated (67 strains) from blood cultures were serotyped by latex agglutination (Pneumotest latex) and Quellung reaction (Statens Serum Institut, Denmark). Antimicrobial susceptibility testing to penicillin (PEN), cefotaxime (CT), erythromycin (ERY) and levofloxacin (LEV) was performed by the E-test method (Biomèrieux, France).


RESULTS
Among the 67 strains isolated, the most prevalent serotypes were 22F (11.9%) and 3 (11.9%), the second most frequent were 7F (7.5%) and 19A (7.5%). The coverage of the strains by the pneumococcal 7-valent conjugate vaccine (VNC7V), pneumococcal 13-valent conjugate vaccine (VNC13V) and pneumococcal 23-valent polysaccharide (VNP23V) were 16, 49 and 82%, respectively. Serotypes 22F and 3 were responsible for 14 of the 48 episodes of pneumonia with bacteremia (29.2%) and only 2 of the 19 episodes (10.5%) of bacteremia without pneumonia. According to the 2007 CLSI criteria, 12 strains (17.9%) were non-susceptible to penicillin. Eleven of this 12 strains (91.7%) were resistant to erythromycin, simultaneously.


CONCLUSIONS
The most common serotypes were 22F, 3, 7F y 19A. Three of them (3, 7F y 19A) are serotypes that are covered by the new VNC13V but not by VNC7V. Serotype 22F is a serotype emergent that is not covered by the VNC7V. The percentage of non-susceptibility to penicillin and resistance to erythromycin was comparable to the percentage reported in our country.
Hospital Universitario de la Princesa. Servicio de Microbiología, c/ Diego de León, 62 ,28006 Madrid, Spain. ana-correa@hotmail.es
Ana María
AM
Correa
Juan Carlos
JC
Sanz
Carmen
C
de Las Cuevas
Alba
A
Guiu
Diego
D
Domingo
Teresa
T
Alarcón
Manuel
M
López-Brea
D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004917:Erythromycin / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008586:Meningitis, Pneumococcal / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D010403:Penicillin Resistance; D011008:Pneumococcal Infections / Q000097:blood* / Q000382:microbiology; D012703:Serotyping; D013030:Spain; D013296:Streptococcus pneumoniae / Q000187:drug effects*
D000900:Anti-Bacterial Agents; D004917:Erythromycin