Pediatric Hydatid Disease

  • Etiology: Ingesting food contaminated with Echinococcus eggs results in infection by Echinococcus tapeworm leading to cyst formation anywhere in body
  • Imaging:
    — Cysts have 3 components: Pericyst which is inflammatory tissue around cyst, exocyst, endocyst containing scolicies (larval stage of parasite) and laminated membrane
    — 4 types of cysts: Type I is simple cyst, Type II has daughter cysts(s), Type III is calcified and thus dead, Type IV is ruptured cyst
  • DDX:
  • Complications: Cysts can rupture
  • Treatment:
    — Surgical excision
    — PAIR (Puncture, Aspiration, Injection of protoscolicidal agent, Reaspiration)
    — Chemotherapy with anti-helminthic agent
    — Watching and waiting for inactive and silent cysts
  • Clinical:
    — Diagnose via Casoni skin test
    — Most common locations are liver (76%) and lungs (15%) and spleen (5%)

Radiology Cases of Hydatid Disease

CXR of hydatid disease
CXR PA and lateral shows a large mass without calcification in the posterior aspect of the right lung which on cross sectional imaging was seen to be cystic in nature.

Gross Pathology Cases of Hydatid Disease

Pathology image of hydatid disease
Gross pathological images show a large cystic structure without internal septations.