Isam A. Eltoum

Kala-azar: a comparative study of parasitological methods and the direct agglutination test in diagnosis

In a comparative study 88 patients were diagnosed as suffering from kala-azar (visceral leishmaniasis) using 3 parasitological methods simultaneously. Splenomegaly was absent in 4 cases. In 84 patients with splenomegaly, splenic aspiration appeared to be the most sensitive method (96.4%), followed by bone marrow aspiration (70.2%) and lymph node aspiration (58.3%). There was no relation between titres in the direct agglutination test and parasite load as determined by the number of parasitological methods which were positive or parasite density in splenic aspirates. Splenic aspiration and bone marrow aspiration were compared as an assessment of cure in kala-azar. In 6 (13%) of 46 patients tested, parasites were found, all by splenic aspiration. Bone marrow showed parasites in one of these. The literature with regard to parasitological investigations before and after treatment is reviewed.

Post kala-azar dermal leishmaniasis in the Sudan: clinical features, pathology and treatment

The clinical features, pathology, immune responses, diagnosis and treatment of post kala-azar dermal leishmaniasis (PKDL) in the Sudan are described and discussed. The disease is characterized by maculopapular or nodular lesions on the face, limbs or trunk. Lesions appear during or within months after the treatment of visceral leishmaniasis, but in 2 of 19 patients there was no previous history of kala-azar. PKDL may be confused with leprosy both clinically and pathologically. Similarities and differences between the 2 diseases are discussed. Unlike visceral leishmaniasis, the peripheral lymphoid cells of patients with PKDL respond to Leishmania antigen and some are leishmanin positive. The response to intravenous sodium stibogluconate (20 mg/kg for 30 d) was reasonably good but some patients required repeated or more prolonged treatment. Ketoconazole in a dose of 10 mg/kg daily for 4 weeks had no effect on PKDL.

Kala-azar in displaced people from southern Sudan: epidemiological, clinical and therapeutic findings

Six hundred and ninety-three patients with kala-azar were seen in Khartoum, Sudan, from January 1989 to February 1990. They were almost exclusively from the Nuer tribe, originating from the western Upper Nile province in southern Sudan, an area not known previously to be endemic for kala-azar. Because of the civil war in southern Sudan no treatment was available locally and massive migration to northern Sudan occurred; many died on the way. All age groups were affected; there was a slight male preponderance (56%). In the clinical presentation, marked generalized lymphadenopathy was prominent (84%). Splenomegaly was absent in 4% of cases. Patients usually showed anaemia, leucopenia and/or thrombocytopenia. 623 patients were treated with sodium stibogluconate, 10 mg/kg for 30 d; relapse occurred in 4% and death in 12%. Latterly, 70 patients were treated with sodium stibogluconate at 2 x 10 mg/kg for 15 d, with relapse in 6% and death in 6%. The difference between the 2 regimens in the number of relapses and deaths was not significant. The outbreak may have been caused by a combination of factors: the introduction of the parasite from an endemic area to a non-immune population, the presence of malnutrition caused by loss of cattle and unavailability of other food sources, and possibly an ecological change in favour of the sandfly vector.

Clinical Aspects of Kala-azar in Children from the Sudan: A Comparison with the Disease in Adults

The clinical presentation of kala-azar in 43 children and 45 adults was compared. In both groups fever, left upper quadrant abdominal pain and swelling, and weight loss were equally the most common presenting symptoms. Lymphadenopathy was observed in 86 per cent of children and 76 per cent of adults. Splenomegaly was absent in 2 per cent of children and 7 per cent of adults. No significant difference was found in frequency distribution of symptoms and signs between children and adults. Haematological indices were compared in both children and adults with kala-azar and their control groups. In both children and adults with kala-azar, haemoglobin concentration, total white cell count, and platelet count were significantly lower before than after treatment. Only haemoglobin concentration was lower in children with kala-azar as compared with adults with the disease. Children in the control group had lower haemoglobin and higher total white cell count than adult controls. Response to therapy was evaluated in 693 patients. Two-hundred-and-fifty children and 373 adults were treated with sodium stibogluconate 10 mg/kg for 30 days; in both groups 12 per cent deaths and 4 per cent relapses occurred. Thirty children and 40 adults were treated with sodium stibogluconate 2 x 10 mg/kg for 15 days. In children, 3 per cent deaths and 7 per cent relapses were noted; in adults there were 8 per cent deaths and 5 per cent relapses. No significant difference in death rate or relapse rate was found between children and adults in both regimens. Both regimens performed equally well in children and adults with regard to death rate and relapse rate.

Post-Kala-Azar Dermal Leishmaniasis in The Sudan: Peripheral Neural Involvement

Four patients developed post‐kala‐azar dermal leishmaniasis and neuritis (PKDL) 1 to 6 months following apparently successful treatment of kala‐azar. The duration of the lesion varied between 1 month and nearly 5 years. The lesions were macules, papules, or nodules affecting the face, extremities, and trunk. The diagnosis was made by demonstration of the parasite in slit smear and biopsies and by a positive direct agglutination test (DAT). Histologically, the patients were found to have neuritis affecting the cutaneous nerves in the lesion only. The nerves showed a lymphohistiocytic infiltration and occasionally parasites. There was no impairment of sensation. Response to sodium stibogluconate was good. PKDL may simulate leprosy both clinically and pathologically.

Evaluation of haematuria as an indirect screening test for schistosomiasis haematobium: a population-based study in the White Nile Province, Sudan

Haematuria elicited in the history, seen macroscopically or detected by reagent strips, was used as an indirect screening test for Schistosoma haematobium infection in Um-Hani Irrigation Scheme in the White Nile province, Sudan. These approaches were used separately or combined in different sequences. Reagent strips alone detected 81% of cases and 88% of those who excreted 50 egg/10 ml of urine or more. The sequence of observation of gross haematuria followed by screening with reagent strips and then taking history of haematuria had the highest sensitivity of all the orders, 0.87, and it saved 18% of reagent strips. If history and inspection were done first, followed by reagent strips, the sensitivity would be 0.86 and 47% of strips would be saved. The specificity of haematuria as a diagnostic index for schistosomiasis, however, was low.

The treatment of kala-azar in the Sudan with sodium stibogluconate: a randomized trial of three dosage regimens

In a randomized study in the Sudan, 3 different regimens of sodium stibogluconate were compared in patients with parasitologically confirmed kala-azar (visceral leishmaniasis): 10 mg/kg for 30 d (38 patients), 20 mg/kg for 30 d (29 patients), and 20 mg/kg for 15 d (37 patients). Treatment failures were defined as death, partial response, relapse, or the development of post-kala-azar dermal leishmaniasis. The hazard ratio for failure of 20 mg/kg for 30 d vs. 10 mg/kg for 30 d 2.1 (95% confidence interval [CI] = 0.6, 7.6) and for 20 mg/kg for 15 d vs. 10 mg/kg for 30 d it was 1.7 (95% CI = 0.5, 6.1). No significant difference was detected between the 3 regimens in the rate of return to normal of haematological criteria, regression of spleen size, or weight gain. After 15 d treatment parasite clearance with 20 mg/kg for 30 d and 20 mg/kg for 15 d was more profound than with 10 mg/kg for 30 d (P < 0.05), but the difference was no longer present at the end of treatment. Further investigation of the effectiveness of short, intensive treatment regimens in the treatment of kala-azar is warranted.