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Published on: April 9, 2012
Microorganisms isolated at admission and treatment outcome in sputum smear-positive pulmonary tuberculosis
Satoru Ishikawa1, Hidetoshi Igari2, Kazutaka Yamagishi2
1National Hospital Organization Chiba-East Hospital, Department of Respiratory Medicine, 673 Nitona-cho, Chuoh-ku, Chiba 260-8712, Japan; Japan Community Health Care Organization Funabashi Central Hospital, Department of Internal Medicine, 6-13-10 Kaijin, Funabashi, Chiba 273-8556, Japan.
Abstract:
Cured or completed cases in newly diagnosed sputum smear-positive pulmonary tuberculosis (TB) is 47.7% in Japan in 2016. Aging of TB patients and their underlying conditions could affect treatment outcome. We analyzed the association between the isolation of microorganisms from sputum at admission and the 180-day mortality rate of the sputum smear-positive pulmonary TB patients in Chiba-East Hospital in Japan. Total subjects were 761 (median age: 63 years). Sputum test for microorganisms was conducted in 708 patients. Microorganisms other than the normal oral flora were isolated in 128 cases (18.1%). Details of the isolated microorganisms were as follows: methicillin-resistant Staphylococcus aureus 23 cases, Klebsiella pneumoniae 17 cases, Pseudomonas aeruginosa 16 cases. Mortality was significantly elevated in the patients with those microorganisms than the others (39.8% vs. 10.2%) (P < 0.01). Fifty-one of 128 patients with those microorganisms died, and 10 of them died of infectious disease, which is the most frequent cause of deaths. The factors associated with the isolation of those microorganisms were as follows: respiratory failure (adjusted odds ratio (aOR):2.5 [95% confidence interval (CI) 1.3-4.7]), performance status 3 or 4 (aOR:2.9 [95% CI 1.6-5.4]), serum albumin <3.0 mg/dL (aOR:2.1 [95% CI 1.3-3.6], age of 65 years or older (aOR:2.0 [95% CI 1.2-3.4]). Those strains were isolated from one of sixth patients. Patients with those microorganisms did not always develop infectious diseases; however, treatment outcomes were poor, with higher mortality. The isolations of microorganisms were associated with various underlying conditions, leading to death. Thus, attention should be paid to TB patients with the above factors.
Insights
In Japan, nearly one in six tuberculosis patients had other microorganisms in their sputum, leading to significantly higher mortality rates. These findings highlight the need for careful monitoring of tuberculosis patients with specific underlying conditions.
Area of Science:
- Infectious Diseases
- Microbiology
- Pulmonary Medicine
Background:
- Tuberculosis (TB) treatment outcomes in Japan are impacted by patient demographics and comorbidities.
- Sputum smear-positive pulmonary TB patients face challenges with aging and underlying health issues.
- Understanding factors affecting TB mortality is crucial for improving patient care.
Purpose of the Study:
- To investigate the association between the isolation of microorganisms from sputum and the 180-day mortality rate in newly diagnosed sputum smear-positive pulmonary TB patients.
- To identify specific microorganisms and patient factors linked to increased mortality.
- To inform clinical attention towards high-risk TB patient groups.
Main Methods:
- Retrospective analysis of 761 sputum smear-positive pulmonary TB patients admitted to Chiba-East Hospital, Japan.
- Sputum cultures performed on 708 patients to identify non-oral flora microorganisms.
- Statistical analysis to determine the association between microorganism isolation and 180-day mortality, controlling for confounding factors.
Main Results:
- Microorganisms other than normal oral flora were isolated in 18.1% (128/708) of patients.
- Isolated pathogens included methicillin-resistant Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa.
- Mortality was significantly higher in patients with isolated microorganisms (39.8%) compared to others (10.2%) (P < 0.01).
- Factors associated with microorganism isolation included respiratory failure, poor performance status, low serum albumin, and age ≥ 65 years.
- Infectious disease was the most frequent cause of death among patients with isolated microorganisms.
Conclusions:
- Isolation of non-oral flora microorganisms from sputum in TB patients is linked to significantly elevated 180-day mortality.
- Underlying conditions such as respiratory failure, poor performance status, hypoalbuminemia, and advanced age are associated with the presence of these microorganisms.
- Clinical vigilance is warranted for TB patients presenting with these risk factors to mitigate poor treatment outcomes and mortality.
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