Thoracic empyema caused by Prevotella spp. diagnosed using 16S rDNA sequence analysis

Hua Zhou1, Yihong Shen, Qian Shen

  • 1Department of Respiratory, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.

Insights

A challenging thoracic empyema case highlights the limitations of routine diagnostics for anaerobic bacteria. Molecular assays like 16S ribosomal DNA sequencing are crucial for accurate identification and effective treatment of pleural infections.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Pulmonology

Background:

  • Thoracic empyema, a serious pleural infection, can be challenging to diagnose and treat.
  • Comorbidities such as diabetes mellitus and hypertension can complicate patient management.

Observation:

  • A 76-year-old male with diabetes and hypertension presented with fever and chest pain, diagnosed with pleural infection.
  • Initial treatment with drainage and moxifloxacin, followed by anti-tuberculosis drugs for suspected tuberculous pleuritis, failed to resolve persistent fever.

Findings:

  • Gram stain of pleural pus revealed a gram-negative bacillus, identified as Prevotella spp. via 16S ribosomal DNA sequencing.
  • Standard cultures of various samples were negative, underscoring the limitations of conventional methods for anaerobic organisms.

Implications:

  • This case emphasizes the importance of considering anaerobic Prevotella species in refractory pleural infections.
  • Molecular diagnostic techniques, such as 16S rDNA sequencing, are vital for identifying difficult-to-culture pathogens in thoracic empyema.
  • Accurate identification led to effective treatment with imipenem and metronidazole, resulting in patient recovery and no recurrence.

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