[Histology of liver lesions due to Schistosoma mekongi. About six cases with severe portal hypertension operated in Cambodia].

Schistosomiasis mekongi was shown to be endemic, along the Mekong River, in northern Cambodia, affecting many patients with portal hypertension. Surgical procedures were proposed to some patients with digestive haemorrhage history to avoid fatal recurrence. The aim of our study was to evaluate the intensity of the liver fibrosis among these patients. During surgical treatment, liver biopsies were collected, fixed in Bouin or in formalin and processed at the Institut Pasteur of Cambodia. Sections were stained by H&E, Masson's trichrome, PAS, Ziehl-Neelsen's method and Congo Red. A total of six biopsies from patients aged 16-36 were analysed. There was complete disorganization of hepatic architecture with fibrous enlargement of portal tracts and some portal-portal bridging fibrosis, but there was no cirrhosis. In portal areas, there was blood vessel congestion and thrombosis with inflammation. Bile ducts were normal. In the parenchyma, congestion of sinusoidal capillaries was combined with focal mononuclear inflammatory infiltrate. There was no steatosis, no necrosis, no cholestasis, no iron accumulation and no amyloidosis. Numerous eggs of Schistosoma mekongi were observed in five cases, mostly in fibrous areas and more rarely in the parenchyma. Eggs were round or oval, measuring 60 x 40 microns with an acid-fast thin hyaline wall. Some eggs were surrounded by epithelioid and giant cell reaction. In conclusion, our findings illustrated a surprisingly high degree of fibrosis among young adults which contrasts with other schistosomiasis.