Mechanized Pneumonia Secondary to Legionella Infection with Diarrhea as the First Manifestation: a Case Report
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Published on: November 22, 2013
Background:
Legionella is a Gram-negative bacterium, and Legionella pneumonia is an atypical pneumonia, clinically similar to Streptococcus pneumoniae or other bacterial pneumonia, with respiratory symptoms as the most common clinical manifestation, but very few patients have a predominantly GI symptom presentation, which often leads to delayed treatment; timely and effective standardized treatment has a good prognosis, and individual patients can develop mechanized pneumonia. Therefore, we report a case of Legionella infection with diarrhea as the first manifestation secondary to mechanized pneumonia.
Methods:
bronchoscopy, percutaneous lung aspiration biopsy, infection pathogen macrogenomics next-generation assay (mNGS).
Results:
The patient was examined by bronchoscopy and NGS was performed suggesting the presence of Legionella and poorly absorbed by the treated pulmonary lesion condition. Therefore, we further improved the pathology of percutaneous lung puncture biopsy suggesting the presence of mechanized pneumonia and gave the patient symptomatic treatment.
Conclusions:
For severe pneumonia with non-respiratory symptoms as the first manifestation, we need to clarify the infecting pathogen as early as possible, and we also need to evaluate the anti-infective efficacy in a timely manner. After a full course of treatment with active pathogen coverage and imaging suggesting poor absorption, bronchoscopy or percutaneous lung biopsy should be perfected in a timely manner to obtain pathological tissue to further clarify the condition.
Insights
This case highlights Legionella pneumonia presenting initially with gastrointestinal symptoms like diarrhea, leading to delayed diagnosis. Early pathogen identification and targeted treatment are crucial for severe pneumonia cases with atypical presentations.
Area of Science:
- Infectious Diseases
- Pulmonology
- Microbiology
Background:
- Legionella pneumonia, an atypical pneumonia, typically presents with respiratory symptoms.
- Gastrointestinal symptoms are uncommon but can lead to delayed diagnosis and treatment.
Observation:
- A case of Legionella infection initially manifested with diarrhea, preceding respiratory symptoms.
- The patient developed secondary mechanised pneumonia.
Findings:
- Bronchoscopy and next-generation sequencing (NGS) suggested Legionella infection.
- Percutaneous lung biopsy confirmed mechanised pneumonia, with poor response to initial treatment.
Implications:
- Emphasizes the need for early pathogen identification in severe pneumonia with non-respiratory symptoms.
- Highlights the importance of timely diagnostic procedures like bronchoscopy or lung biopsy for refractory cases.
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