Noncirrhotic portal hypertension in HIV-infected patients: unique clinical and pathological findings.

BACKGROUND: Liver disease of unknown cause in HIV-infected persons is rare but increasingly being reported. Noncirrhotic portal hypertension is the main feature in a subset of these patients, in whom gastrointestinal bleeding is the most frequent and potentially life-threatening clinical presentation.
METHODS: We describe the epidemiological, clinical and histological features of 12 HIV-positive individuals presenting with noncirrhotic portal hypertension.
RESULTS: An interpretable liver biopsy was available in 11, and cirrhosis was absent in all patients. Three patients had nodular regenerative hyperplasia of the liver, whereas eight showed morphological features previously described as 'hepatoportal sclerosis'. In four of the later group, a distinctive lesion was noted characterized by massive absence of portal veins along with focal fibrous obliteration of small portal veins. All patients had been treated with didanosine for long periods and inflammatory and thrombotic processes hypothetically triggered by this purine analogue in the hepatic microvasculature might result in this form of obliterative portal venopathy.
CONCLUSION: Noncirrhotic portal hypertension is a rare but unique entity presenting in HIV-positive individuals generally with prior prolonged exposure to didanosine, which shows an obliteration of portal veins as the most distinctive histological finding in the liver.