The bacterial aetiology of adult community-acquired pneumonia in Asia: a systematic review.
BACKGROUND
Community-acquired pneumonia (CAP) is a major cause of adult mortality in Asia. Appropriate empirical treatment depends on knowledge of the pathogens commonly responsible. However, assessing the aetiological significance of identified organisms is often difficult, particularly with sputum isolates that might represent contamination with oropharyngeal flora.


METHODS
A systematic review of all adult CAP aetiology studies from Asia, excluding the Middle East, published in English between 1 January 1990 and 1 March 2012 was conducted. Forty-eight studies reporting on 10 423 patients were included, representing data from China, India, Indonesia, Japan, Malaysia, The Philippines, Singapore, South Korea, Taiwan, Thailand and Vietnam. Data from large parts of Asia were unavailable and there was substantial heterogeneity in methodology.


RESULTS
As in western studies, Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella spp. and Haemophilus influenzae were all significant pathogens. However, compared with western studies, S. pneumoniae was of less relative importance. Gram-negative bacilli and Mycobacterium tuberculosis were more important, and in northeast Thailand Burkholderia pseudomallei was a major pathogen.


CONCLUSIONS
These data have major implications for diagnostic strategies and empirical treatment. Narrow-spectrum antibiotics targeting S. pneumoniae may be inappropriate in many Asian settings, and agents active against TB may lead to partial response and delayed TB diagnosis.
Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hanoi and Ho Chi Minh City, Vietnam Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Oxford OX3 7LJ, UK.
Leon
L
Peto
Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hanoi and Ho Chi Minh City, Vietnam Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Oxford OX3 7LJ, UK bnadjm@yahoo.com.
Behzad
B
Nadjm
Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hanoi and Ho Chi Minh City, Vietnam Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Oxford OX3 7LJ, UK.
Peter
P
Horby
National Hospital for Tropical Diseases, Hanoi, Vietnam.
Ta Thi Dieu
TT
Ngan
Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hanoi and Ho Chi Minh City, Vietnam Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Oxford OX3 7LJ, UK.
Rogier
R
van Doorn
National Hospital for Tropical Diseases, Hanoi, Vietnam.
Nguyen
N
Van Kinh
Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hanoi and Ho Chi Minh City, Vietnam Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Oxford OX3 7LJ, UK.
Heiman F L
HF
Wertheim
D000328:Adult; D000368:Aged; D001208:Asia / Q000453:epidemiology; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D013183:Sputum / Q000382:microbiology
Asia; Community-acquired; Microbiology; Mycobacterium tuberculosis; Pneumonia; Streptococcus pneumoniae