Paragonimiasis in a child with massive pericardial effusion as the primary manifestation: a case report

Paragonimiasis in children is rare as isolated pericardial effusion, especially when presenting despite the absence of elevated eosinophilia. We report such a case to highlight this atypical manifestation. A 10-year-old male child was admitted to the hospital with “pericardial effusion found for 5 days”. The initial differential diagnosis included infectious, autoimmune, and neoplastic causes of pericarditis. Laboratory tests on admission showed normal serum and pericardial effusion eosinophils, and the pericardial effusion was positive for paragonimiasis IgG. Multiple cardiac ultrasounds revealed a large pericardial effusion and progressive pericardial thickening (up to 6.5 mm) with nodular changes. After praziquantel deworming and resection of the pericardial mass, pathology confirmed necrosis with granulomatous inflammation, consistent with parasitic infection and ruling out other etiologies in the differential. The child recovered well after surgery, and the pericardial effusion disappeared. Children with paragonimiasis may present with isolated pericardial lesions but normal range of eosinophils, and early recognition and confirmation of the diagnosis is essential for prognosis.