1224. Relationship of Streptococcus pneumoniae Serotypes with Clinical Failure in Hospitalized Patients with Community-acquired Pneumonia
Session: Poster Abstract Session: Pneumococcal Epidemiology
Saturday, October 22, 2011
Room: Poster Hall B1
Background: Positive blood cultures are documented in about 10-14% of hospitalized patients with community-acquired pneumonia (CAP).  Streptococcus pneumoniae (Sp) is the most common pathogen isolated from these blood cultures.  Data are scarce regarding the relationship between Sp serotypes and clinical outcomes.  The objective of this study was to assess if a relationship exists between Sp serotypes and clinical failure in hospitalized, bacteremic patients with CAP.

Methods: This was a secondary analysis of the Community-Acquired Pneumonia Organization (CAPO) international cohort study database [data from 5 hospitals (Spain, Argentina, Canada, South Africa, and U.S.) from 2001-2011].  Description of the cohort and the clinical failure rate for patients with bacteremic CAP due to Sp with known serotypes (n=143) was compared to the clinical failure rate of all patients with bacteremic Sp (not serotyped) (n=390) in the CAPO database.  Only serotypes with ≥ 5 isolates were analyzed.

Results: A total of 143 patients had Sp serotype performed. The mean patient age was 53 years old and 78 (54.5%) were male; 47 patients (33 %) were HIV + and 10 (7%) had documented prior Sp vaccination. Serotype 19A was isolated in the most patient for the entire cohort [33 patients (23%)], followed by serotype 1 and 3 in 13 cases (9%); the predominant serotype varied by location. Bacteremic patients with CAP due to Sp in the CAPO database (with no serotyping) had a clinical failure rate of 42% (95% CI:37%-47%).  The clinical failure of patients with CAP due to Sp who had serotyping performed was 44% (varying by serotype, 17% to 60%).  Serotypes associated with worse clinical outcomes were 19A, 9V, 9N, 14, 12F, 23A, and 4. Those patients with clinical failure compared to clinical success had similar demographics and co-morbid illnesses.  Mortality was 16% (23/143 patients).   

Conclusion: This study suggests that, when compared to the average clinical failure for a CAP patient with bacteremia, certain serotypes of Sp are associated with a decreased risk and others with an increased risk for clinical failure.  Since most serotypes associated with clinical failure are in the current Sp 23 valent vaccine, improving vaccination rates may impact clinical failure in hospitalized patients with CAP.


Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Diana Christensen, MD1, Belinda Ostrowsky, MD, MPH2, Catia Cillóniz, MSc3, Catherine Baillargeon, MD4, Lautaro de Vedia, MD5, Viv Herbert6, Eva Polverino7, Charles Feldman, MD6, Antoni Torres, MD, Phd8, Karl Weiss, MD9, Anne von Gottberg, MBBCh10, Timothy Wiemken, PhD11, Paula Peyrani, MD12, Phillip Gialanella, MS13, Liise-anne Pirofski, MD, FIDSA14, Julio Ramirez, MD11 and Capo Investigators12, (1)Infectious Diseases, Montefiore Medical Center, NY, NY, (2)Infectious Diseases, Montefiore Medical Center, Bronx, NY, (3)Microbiology, Hospital Clínic CIBERES, Barcelona, Spain, (4)Maisonneuve-Rosemont Hospital, Montreal , QC, Canada, (5)Infectious Diseases, Hospital Muñiz , Buenos Aires, Argentina, (6)Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa, (7)Servicio de Neumología, Hospital Clínic de Barcelona , Barcelona, Spain, (8)Pneumology, Hosp. Clínic de Barcelona, Barcelona, Spain, (9)Hop. Maisonneuve-Rosemont, Montreal, QC, Canada, (10)National Institute for Communicable Diseases, Johannesburg, South Africa, (11)Division of Infectious Diseases, University of Louisville, Louisville, KY, (12)Infectious Diseases, University of Louisville, Louisville, KY, (13)Microbiology laboratory Montefiore Medical Center, Bronx, NY, (14)Division of Infectious Diseases, Albert Einstein College of Medicine, Bronx, NY

Disclosures:

D. Christensen, Pfizer: Grant Investigator, Educational grant

B. Ostrowsky, None

C. Cillóniz, None

C. Baillargeon, None

L. de Vedia, None

V. Herbert, None

E. Polverino, None

C. Feldman, None

A. Torres, Pfizer: Consultant, Consulting fee and Research grant
Covidien: Consultant, Consulting fee and Research grant
Astellas: Consultant, Consulting fee and Research grant

K. Weiss, Pfizer Inc: Research Contractor, Research support

A. von Gottberg, None

T. Wiemken, None

P. Peyrani, None

P. Gialanella, None

L. A. Pirofski, None

J. Ramirez, None

C. Investigators, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.