Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited.
BACKGROUND
Invasive infection with Streptococcus pneumoniae (pneumococci) causes significant morbidity and mortality. Case series and experimental data have shown that the capsular serotype is involved in the pathogenesis and a determinant of disease outcome.


METHODS
Retrospective review of 464 cases of invasive disease among adults diagnosed between 1990 and 2001. Multivariate Cox proportional hazard analysis.


RESULTS
After adjustment for other markers of disease severity, we found that infection with serotype 3 was associated with an increased relative risk (RR) of death of 2.54 (95% confidence interval (CI): 1.22-5.27), whereas infection with serotype 1 was associated with a decreased risk of death (RR 0.23 (95% CI, 0.06-0.97)). Additionally, older age, relative leucopenia and relative hypothermia were independent predictors of mortality.


CONCLUSIONS
Our study shows that capsular serotypes independently influenced the outcome from invasive pneumococcal disease. The limitations of the current polysaccharide pneumococcal vaccine warrant the development of alternative vaccines. We suggest that the virulence of pneumococcal serotypes should be considered in the design of novel vaccines.
Martens
Pernille
P
Department of Infectious Diseases 144, Hvidovre University Hospital, DK-2650 Hvidovre, Denmark. pernillemartens@yahoo.com
Worm
Signe Westring
SW
Lundgren
Bettina
B
Konradsen
Helle Bossen
HB
Benfield
Thomas
T
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000382:microbiology / Q000401:mortality; D016667:Bacterial Capsules / Q000145:classification*; D024881:Drug Resistance, Bacterial; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008586:Meningitis, Pneumococcal / Q000382:microbiology / Q000401:mortality; D008875:Middle Aged; D010033:Otitis Media / Q000382:microbiology / Q000401:mortality; D011008:Pneumococcal Infections / Q000382:microbiology* / Q000401:mortality*; D011018:Pneumonia, Pneumococcal / Q000382:microbiology / Q000401:mortality; D012189:Retrospective Studies; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000187:drug effects / Q000472:pathogenicity; D014774:Virulence