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Exacerbating factors in elderly patients with Mycobacterium avium complex pulmonary disease
Norio Kodaka1, Chihiro Nakano1, Takeshi Oshio1
1Division of Respiratory Medicine, Department of Internal Medicine, Toho University Ohashi Medical Center, Tokyo, Japan.
Abstract:
No previous studies have examined Mycobacterium avium complex pulmonary disease (MAC-PD) in only elderly patients ⩾75 years old. Here, we investigated the exacerbating factors of MAC-PD in elderly patients and clarified cases that can be followed up without MAC medication. From April 2011 to March 2019, 126 advanced aged patients at our institute were newly diagnosed with MAC-PD, and could be observed based on radiological findings for over a year. Their medical records were retrospectively examined for clinical and radiological findings at the time of diagnosis and 1 year later. To identify the predictors of exacerbation, clinical characteristics of 109 treatment-naïve patients were compared between exacerbated and unchanged groups. Additionally, the unchanged group was followed for one more year. In the current study, positive acid-fast bacilli smears from the sputum test, the presence of cavitary lesions and extensive radiological findings, particularly abnormal shadows in ⩾3 lobes, were predictive of exacerbation among treatment-naïve elderly MAC-PD patients. In the unchanged group, <10% showed exacerbation of radiological findings within the subsequent year. In conclusion, if the sputum smear is negative, no cavitary lesions are present, and abnormal shadows are restricted to ⩽2 lobes, elderly patients with MAC-PD may remain untreated for a few years.
Insights
Elderly patients with Mycobacterium avium complex pulmonary disease (MAC-PD) may not require immediate treatment. Key indicators for monitoring without medication include negative sputum smears, absence of cavitary lesions, and limited lung involvement.
Area of Science:
- Pulmonology
- Infectious Diseases
- Geriatrics
Background:
- Mycobacterium avium complex pulmonary disease (MAC-PD) is increasingly recognized, particularly in elderly populations.
- Limited research exists specifically on MAC-PD management and exacerbating factors in patients aged 75 and older.
- Identifying patients who can be safely monitored without immediate antimicrobial therapy is crucial for optimizing care.
Purpose of the Study:
- To investigate factors predicting exacerbation in elderly patients (≥75 years) diagnosed with MAC-PD.
- To identify clinical and radiological characteristics that allow for conservative management (i.e., observation without MAC medication).
- To evaluate the long-term outcomes of elderly MAC-PD patients managed conservatively.
Main Methods:
- Retrospective analysis of 126 elderly patients (≥75 years) newly diagnosed with MAC-PD between April 2011 and March 2019.
- Assessment of clinical and radiological findings at diagnosis and one year later.
- Comparison of clinical characteristics between exacerbated and unchanged groups among 109 treatment-naïve patients to identify exacerbation predictors.
Main Results:
- Positive acid-fast bacilli sputum smears, presence of cavitary lesions, and extensive radiological findings (abnormal shadows in ≥3 lobes) predicted exacerbation in treatment-naïve elderly MAC-PD patients.
- In the group not requiring immediate treatment, less than 10% showed radiological exacerbation within the following year.
- These findings suggest specific criteria for conservative management.
Conclusions:
- Elderly patients with MAC-PD and negative sputum smears, no cavitary lesions, and limited radiological involvement (≤2 lobes) may be safely observed without immediate MAC medication for several years.
- This approach can help avoid unnecessary treatment burdens and potential side effects in select elderly patients.
- Further prospective studies could validate these findings and refine management guidelines for this specific demographic.
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