SummarySerologically positive individuals without parasitological confirmation constitute an important problem for trypanosomiasis control programmes because of epidemiological and therapeutical consequences. In July 1997, in the focus of Quiçama (Angola), 4753 individuals were screened using CATT/T.b.gambiense on whole blood. In CATT-positive but parasite-negative individuals, CATT titration on serum was performed. Sixteen individuals showing an end-titre lower than 1/4 were considered noninfected according to the results of a previous study of serological status of parasitologically confirmed cases; 86 individuals with end titres Ն 1/4 were considered suspected of trypanosomiasis and were followed-up from July 1997 to July 1998 with controls every three months. After one year, 32 individuals whose antibody titres dropped Ͻ 1/4 were considered noninfected, 22 were confirmed by demonstration of parasites, 17 were further followed-up because antibody titres remained Ն 1/8 but parasites could not be found. Fifteen individuals did not show up for testing. Following the usual criterion, only parasitologically confirmed cases were treated. However, if it had been decided to treat parasite-negative individuals with a CATT end-titre Ͼ 1/8, 22 initially unconfirmed but infected individuals would have been treated earlier, whereas 5 noninfected individuals would have been treated unnecessarily. CATT titration on diluted serum or plasma is useful for making therapeutical decisions.

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Southern Sudan is one of the areas in eastern Africa most affected by visceral leishmaniasis (kala-azar), but lack of security and funds has hampered control. Since 2005, the return of stability has opened up new opportunities to expand existing interventions and introduce new ones.

Chronic paracetamol poisoning is a potential risk factor for hepatotoxicity and acute liver failure. Delays in seeking medical help might be a contributing factor. Clinicians should have a higher index of clinical suspicion for this entity.

Hirschsprung's disease is characterized by absence of ganglion cells in submucosal and myenteric plexus of distal bowel. Most cases become manifest during the neonatal period, but in rare instances, this disease is initially diagnosed in adult age. It usually presents as severe constipation with colonic dilatation proximal to the aganglionic segment. The treatment is surgical, removing the aganglionic segment and restoring continuity of digestive tract. The disease rarely presents as an acute intestinal obstruction. We report a case not previously diagnosed, which presented as a massive colonic dilatation with a maximum diameter of 44 cm, with imminent risk of drilling that forced to perform an emergency surgery. We include a review of existing literature.