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Tractable Mammalian Cell Infections with Protozoan-primed Bacteria
Published on: April 2, 2013
[Legionella pneumonia--epidemiology, clinical characteristics and development of diagnosis]
K Yamaguchi1, K Tateda, Y Ishii
1Department of Microbiology, Toho University School of Medicine.
Abstract:
We have characterized clinical and diagnostic features in 18 cases of Legionella pneumonia. Age average of patients was 62.0 years old (male: female = 14:4) and underlying diseases were observed in 12 patients. Legionella pneumonia were diagnosed in 3, 5, 7 and 9 cases by culture, serum antibody measurement, urinary antigen detection and PCR, respectively. Sixteen cases were caused by L. pneumophila, while the other 2 cases were due to L. bozemanii and L. pneumophila or L. dumoffii. Chest X-rays of those patients showed multiple pneumonia shadows in 14 cases, alveolar shadows in 10 cases, pleural effusion in 5 cases. Blood-gas analysis on admission indicated hypoxemia in all cases with abnormal A-a DO2. Laboratory findings showed abnormal data in WBC, CRP, LDH, CPK and liver function tests (ex. GOT, GPT) in most cases. Serum antibody testing showed positive by 5 weeks after onset of pneumonia, but 10 cases of Legionella pneumonia diagnosed by other techniques were judged to be negative. In urinary antigen detection test, 6 and 2 cases showed positive 1 and 4 weeks after onset of pneumonia, respectively. Macrolide antibiotics were administered in all cases during the episode, but delay of macrolide administration was observed in 3 of 4 cases of dead outcome. Serum antibody measurement, urinary antigen detection and PCR, in addition to culture of bacteria, may be required for exact diagnosis of Legionella infection.
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