Cryptosporidium parvum is a protozoal infection which causes an acute diarrhoea in immunocompromised patients.

In HIV infection, it can cause a watery diarrhoea which may be associated with anorexia, nausea/vomiting and also abdominal pain.

This patient may have suffered with this diarrhoea for a while as there is no effective treatment (other than supportive treatment) for this infection apart from an antibiotic called; Paromamycin. This drug may have a limited effect on the diarrhoea.