Death or survival from invasive pneumococcal disease in Scotland: associations with serogroups and multilocus sequence types

• Published in: Journal of medical microbiology Vol. 60; no. 6; pp. 793 - 802
• Main Authors: INVERARITY, Donald, LAMB, Karen, EDWARDS, Giles F. S, DIGGLE, Mathew, ROBERTSON, Chris, GREENHALGH, David, MITCHELL, Tim J, SMITH, Andrew, JEFFERIES, Johanna M. C, CLARKE, Stuart C, MCMENAMIN, Jim
• Format: Journal Article
• Language: English
• Published: Reading Society for General Microbiology 01-06-2011
• Subjects: Adolescent; Adult; Age; Aged; Aged, 80 and over; Bacterial diseases; Bacterial Typing Techniques; Biological and medical sciences; Blood; Blood - microbiology; Cerebrospinal fluid; Cerebrospinal Fluid - microbiology; Child; Child, Preschool; Clinical Microbiology and Virology; Data processing; Female; Fundamental and applied biological sciences. Psychology; Haemophilus; Human bacterial diseases; Humans; Infant; Infant, Newborn; Infection; Infectious diseases; Legionella; Male; Medical sciences; Microbiology; Middle Aged; Multilocus Sequence Typing; Neisseria meningitidis; Pneumococcal Infections - epidemiology; Pneumococcal Infections - mortality; Scotland - epidemiology; Serotyping; Staphylococcal infections, streptococcal infections, pneumococcal infections; Streptococcus pneumoniae; Streptococcus pneumoniae - classification; Streptococcus pneumoniae - isolation & purification; Survival; Survival Analysis; Young Adult; United Kingdom; Scotland; Great Britain; Europe; Western Europe; Infection; Bacteriosis; Pneumococcal infection; Streptococcal infection
• ISSN: 0022-2615; 1473-5644
• DOI: 10.1099/jmm.0.028803-0

We describe associations between death from invasive pneumococcal disease (IPD) and particular serogroups and sequence types (STs) determined by multilocus sequence typing (MLST) using data from Scotland. All IPD episodes where blood or cerebrospinal fluid (CSF) culture isolates were referred to the Scottish Haemophilus, Legionella, Meningococcal and Pneumococcal Reference Laboratory (SHLMPRL) from January 1992 to February 2007 were matched to death certification records by the General Register Office for Scotland. This represented 5959 patients. The median number of IPD cases in Scotland each year was 292. Deaths, from any cause, within 30 days of pneumococcal culture from blood or CSF were considered to have IPD as a contributing factor. Eight hundred and thirty-three patients died within 30 days of culture of Streptococcus pneumoniae from blood or CSF [13.95 %; 95 % confidence interval (13.10, 14.80)]. The highest death rates were in patients over the age of 75. Serotyping data exist for all years but MLST data were only available from 2001 onward. The risk ratio of dying from infection due to particular serogroups or STs compared to dying from IPD due to all other serogroups or STs was calculated. Fisher's exact test with Bonferroni adjustment for multiple testing was used. Age adjustment was accomplished using the Cochran-Mantel-Haenszel test and 95 % confidence intervals were reported. Serogroups 3, 11 and 16 have increased probability of causing fatal IPD in Scotland while serogroup 1 IPD has a reduced probability of causing death. None of the 20 most common STs were significantly associated with death within 30 days of pneumococcal culture, after age adjustment. We conclude that there is a stronger association between a fatal outcome and pneumococcal capsular serogroup than there is between a fatal outcome and ST.