Liver and intrahepatic bile ducts - nontumor
Infectious (nonviral) disorders
Schistosomiasis

Author: Komal Arora, M.D. (see Authors page)

Revised: 3 November 2017, last major update May 2012

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Schistosomiasis[TI] liver[TI] full text[sb]

Cite this page: Arora, K. Schistosomiasis. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/liverschisto.html. Accessed December 17th, 2017.
Definition / general
  • Flat worms (trematodes) with species S. haematobium, S. intercalatum, S. japonicum, S. mansoni, S. mekongi
  • All but S. haematobium parasitize intestinal venules and may spread to liver
  • Infect millions in Asia, Africa and South America; rare in US

Infectious cycle:
  • Fresh water snails release cercarial form into water
  • Cercarie are mobile and penetrate human skin or mucosa, enter circulation, pass through lungs and lodge in hepatic branches of portal vein
  • Mature into adults, copulate and migrate to colonic and rectal submucosa where female releases ova that enter colonic lumen, are defecated and infect other snails
  • Ova may also enter portal circulation and cause periportal fibrosis
  • Rarely adult S. mansoni worms are identified in hepatic branches of portal vein (10 - 16 mm)

  • References: Parasite Immunol 2009;31:656
Gross description
  • Pipe stem fibrosis of cut surface
  • No cirrhosis unless coexisting hepatitis B
Microscopic (histologic) description
  • Portal eosinophilic infiltrate with granulomas containing ova with characteristic lateral spine; dense periportal fibrosis
Microscopic (histologic) images

Images hosted on other servers:

Eggs in intestinal mucosa

Dense periportal fibrosis



Images contributed by Dr. Keloth Pradeep, Wrexham Maelor Hospital (United Kingdom):

82 year old woman with liver biopsy for presumed liver metastases, based on CT / MRI findings: schistosomial ova and metastatic adenocarcinoma in liver