Gross and histopathological features of hydatid cysts. Free peritoneal hydatids of different dimensions extracted following laparotomy (A). Peritoneal hydatid tested by period-acid-Schiff (PAS) stain (B). Peritoneal hydatid with laminated layer and a brood capsule budding from the germinal layer (C). Protoscoleces in hydatid cavity. Notice the chain of hooks (arrows) (D). Portion of the spleen occupied by multiple cysts (E). Spleen cysts tested by period-acid-Schiff (PAS) stain (F). Spleen cysts displaying laminated, germinal and adventitial layers with inflammatory and fibrotic reaction (G); Greater magnification of the micrograph G showing the epithelioid rim around the cyst wall, giant cells (arrow) (H). Hematoxylin and eosin staining (H&E). Scale bars 100 μm.