Paragonimiasis

Epidemiology

  • Endemic in Asia

Physiology

  • Ingestion of undercooked or wine-soaked fresh water crustaceans -> excysts in human intestine and fluke penetrates wall -> swims freely in peritoneal cavity -> penetrates diaphragm into pleural space (causing eosinophilic pleural reaction) -> penetration of visceral pleura, causing a parenchymal inflammation (hemoptysis( -> encapsulation by imflammation (forms a fibrotic lung nodule)

Diagnosis

CXR/Chest CT Pattern:
1) Pleural effusion: may be an isolated finding on CXR
2) Lung nodule: well-defined 3-4 cm nodule (may be an isolated finding on CXR)/ lower-lobe predominance/ occasional calcification/ cavitation is common/ multiple ring opacities or thin-walled cysts are characteristic

  • Pleural fluid:
    • Appearance: yellow, non-turbid
    • pH: low
    • LDH ratio: elevated
    • Total protein ratio:
    • Glucose: decreased
    • Cell count/ diff: neutrophil-predominant with eosinophilia

Clinical Presentations

  • Transitory/ self-limited GI complaints (during GI and peritoneal phase): nausea/ bloating/ epigastric pain/ watery diarrhea
  • Hemoptysis/ cough/ dyspnea/ chest pain (during lung phase):
  • Lung Nodule (see [[Lung Nodule or Mass]])
  • Pleural Effusion (see [[Pleural Effusion-Exudate]]

Treatment

  • Praziquantel: prevents late hemoptysis and pulmonary complications

References

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