Serotype prevalence in adults hospitalised with pneumococcal non-invasive community-acquired pneumonia
- Thomas Bewick1,
- Carmen Sheppard2,
- Sonia Greenwood1,
- Mary Slack2,
- Caroline Trotter3,
- Robert George2,
- Wei Shen Lim1
- 1Department of Respiratory Medicine, Nottingham University Hospitals NHS Trust, Nottingham, UK
- 2Respiratory and Systemic Infection Laboratory, Health Protection Agency, Microbiology Services Division, Colindale, London, UK
- 3School of Social and Community Medicine, University of Bristol, Bristol, UK
- Correspondence to Dr Thomas Bewick, Department of Respiratory Medicine, Nottingham University Hospitals NHS Trust, Nottingham NG5 1PB, UK;
- Received 12 September 2011
- Accepted 13 January 2012
- Published Online First 28 February 2012
Background The distribution of pneumococcal serotypes implicated in non-invasive community-acquired pneumonia (CAP) in adults is currently unknown.
Methods A prospective observational cohort study was conducted over 2 years in a large UK teaching hospital trust. Urine samples, in addition to routine blood and sputum samples, were obtained from consecutive adults admitted to the hospital with CAP. Pneumococcal serotype was determined from urine samples using a validated multiplex immunoassay which detects 14 serotypes.
Results Of 920 patients with CAP, 366 had pneumococcal CAP; 242 had a serotype determined. Thirty-day mortality was 10% for all-cause CAP and 9.6% for pneumococcal CAP. Annual incidence of pneumococcal CAP was 36.5 per 100 000, increasing from 12.1 to 274.1 per 100 000 for ages 16–44 years and ≥85 years, respectively. The most prevalent serotypes were 14, 1, 8, 3 and 19A. Less invasive serotypes were significantly associated with increasing age (OR per increasing age group: 1.5, 95% CI 1.2 to 1.9, p<0.001) and co-morbidity (OR per increasing Charlson index group: 1.4, 95% CI 1.0 to 2.0, p=0.036), and with higher 30-day mortality (OR adjusted for age and co-morbidity: 5.5, 95% CI 1.2 to 25.3, p=0.028) compared with highly invasive serotypes. The proportion of patients in whom serotypes contained within the seven-valent childhood pneumococcal conjugate vaccine was identified increased with age (15.6% for patients aged 16–44 years, 41.0% for patients aged ≥85 years; p<0.05).
Conclusions In adult invasive and non-invasive pneumococcal CAP, the most common serotypes implicated were 14, 1, 8, 3 and 19A. Age and co-morbidity were associated with the distribution of serotypes identified.
- respiratory infection
- lung cancer
- non-small cell lung cancer
- pleural disease
- bacterial infection
- clinical epidemiology
- opportunist lung infections
- sleep apnoea
- tobacco and the lung
- viral infection
Funding This work was supported by an unrestricted grant from Pfizer, formerly Wyeth. The study was conceived by the authors and the study design was developed and agreed by the authors without any input from the funding body. The study concept and design was peer reviewed by an independent reviewer prior to ethics approval and prior to award of the grant from the funding body. The funding body was not involved in, and had no influence over, study design, data collection, data analyses, interpretation of results, report writing or in the decision to submit the paper for publication. All study data are held solely by the authors. The sponsor for the study was Nottingham University Hospitals NHS Trust.
Competing interests TB and SG have received salaries derived from an unrestricted grant from Wyeth (now Pfizer). CS and MS have received support for travel to meetings for other purposes from Pfizer. MS is on the advisory boards for Wyeth (now Pfizer), Merck and GlaxoSmithKline, and has received grants from GlaxoSmithKline and Pfizer and has also spoken at scientific meetings organised by Pfizer and GlaxoSmithKline. CT has received a grant from the National Institute of Health Research as part of a personal post-doctoral fellowship. RG and WSL have received unrestricted grants from Wyeth (now Pfizer), and RG has received support for travel to meetings for other purposes and grants from Wyeth (now Pfizer) and GlaxoSmithKline.
Ethics approval This study was approved by the Nottingham regional ethics committee.
Provenance and peer review Not commissioned; externally peer reviewed.