Chronic hepatosplenic schistosomiasis

Chronic infection with Schistosoma mansoni or S. japonica is typically characterised by colonic and hepatic pathology.

Gut involvement may present with abdominal pain and diarrhoea, often accompanied by blood, pus, and mucus in the stools. There may be extensive inflammation of the colon resulting in colonic polyposis and a protein-losing enteropathy.

Hepatic involvement results from eggs laid by adults in the mesenteric venules entering the portal circulation. They become entrapped in the small portal venules of the liver resulting in portal fibrosis, portal hypertension and it's sequelae. Death may arise from a severe variceal bleed.

Other systems may also be affected:

• lungs - eventually resulting in cor pulmonale

Uncommonly:

• CNS - S. mansoni eggs may reach the spinal cord causing a transverse myelitis; those of S. japonica tend to reach the brain where they frequently cause headaches and Jacksonian seizures
• endocrine - particularly, dwarfism and lack of sexual development in the young
• kidneys - increased frequency of mesangioproliferative or membranous glomerulopathy in S. mansoni only