Response of Plasmodium falciparum in Sudan to oral chloroquine.

The chloroquine sensitivity of Plasmodium falciparum was studied in two areas of Sudan. In the Gezira, 99.2% of the patients tested responded completely to the drug. Two patients (0.4%) and one patient (0.2%) showed, respectively, RI and RII responses. However, in those showing RI response reinfection could not be excluded. In an area of southern Sudan patients could only be followed-up for 7 days; nevertheless, this was sufficient to exclude the presence of RII and RIII responses there. This study also showed that malaria is a common cause of fever in Sudan, as over 90% of fever cases tested in the Gezira were positive for malaria and P. falciparum was the predominant species in these cases.

Species prevalence of malaria in northern and southern Sudan, and control by mass chemoprophylaxis.

A survey in northern and southern Sudan showed that Plasmodium falciparum is the predominant species in malaria cases, occurring in 91% and 87%, respectively of the positive cases in these two regions. P. ovale was extremely rare in southern Sudan and was absent in the north. The survey, which was carried out during the transmission season in northern Sudan, showed that malaria is common, occurring in 62% of those tested in some villages. A trial of mass chemoprophylaxis resulted in a marked decline in prevalence after 1 year, demonstrating the importance of chloroquine and establishing that malarial parasites in Sudan are highly sensitive to the drug.

Efficacy of metrifonate in urinary schistosomiasis: comparison of reduction of Schistosoma haematobium and S. mansoni eggs.

Patients with schistosomiasis mansoni and schistosomiasis haematobium from the Gezira area of the Sudan were investigated for the simultaneous presence of Schistosoma mansoni and S. haematobium eggs in urine. Before treatment, 28 or 34 mixed-infection patients constantly excreted eggs of S. mansoni in the urine; however, the concentration was only 1.7% that of S. haematobium eggs. Patients were given two doses of metrifonate (10 mg/kg body weight) 2 weeks apart in order to compare the effect of the organophosphorous compound on the two parasite species. Each dose of metrifonate was followed by a significant decrease in egg output in urine (P less than 0.01). The egg reduction was similar for both parasite species, and was almost 99% after the second treatment. Before treatment was started, a positive correlation existed between the numbers of S. haematobium and S. mansoni eggs excreted in urine (r = 0.75, P less than 0.001), and this correlation did not change after the first or the second dose of metrifonate. After treatment, in 6 of 37 patients S. haematobium eggs and in 8 of 28 patients S. mansoni eggs were not, or were only slightly, reduced. When chemotherapeutic failure of metrifonate against S. haematobium or S. mansoni occurred, it was quantitatively similar for both parasite species.

Physiological performance and work capacity of Sudanese cane cutters with Schistosoma mansoni infection.

Physiological tests of work performance and measurement of field productivity were made in 194 Sudanese cane cutters in order to study the effect of Schistosoma mansoni infection. The cane cutters were selected from two age ranges (16-24 and 25-45 years) and subdivided into three clinical groups: not infected, infected with, and infected without clinical signs of hepatosplenomegaly. Men infected with Schistosoma haemotobium, malaria (blood film), or with hemoglobin levels less than 10 g/100 ml were excluded. There was a statistically significant (P less than 0.002) higher mean hemoglobin concentration in those not infected but the mean difference was less than 1 g/100 ml. Submaximal responses to exercise on a stationary bicycle ergometer, oxygen intake, ventilation, tidal volume, cardiac frequency and estimated maximal aerobic power output calculated both in absolute terms and relative to lean body mass and leg volume were similar in the six groups of cane cutters. No significant differences were found in physique, body composition or in thermoregulatory function tests. The cane cutters were found to have little natural acclimatization to heat in terms of sweating capacity when compared with a group of fully acclimatized Sudanese soldiers. The mean productivity (mean daily weight of cane cut per man) was significantly correlated with the individual's estimated maximum aerobic capacity determined in the laboratory, but not with the degree of S. mansoni infection. The noninfected group was less "efficient" (mean productivity:oxygen intake) during cutting than the infected groups but a larger proportion of the noninfected were in their first season of cutting. There was a positive correlation between the number of seasons' cutting experience and the individual's age, degree of infection and mean productivity. Cane cutters studied in this investigation were a relatively fit, active population from whom the more seriously ill were excluded. These results do not, therefore necessarily reflect the effects of S. mansoni on physiological work capacity and productivity of more static populations in areas of high endemicity.

Migrant workers and schistosomiasis in the Gezira, Sudan.

A cross sectional study of schistosomiasis in migrant laboureres in the Sudan Gezira is described. The people examined were of two ethnic groups: (i) those of local Arabic origin and (ii) those from Western Sudan, West Africa or west of longitude 27 degrees E. These two migrant groups were examined in one area treated with molluscicide and in another that was not. Almost all the schistosome infections were with Schistosoma mansoni, with a prevalence of 57% over-all and up to 89% in particular groups. The prevalence was lower in the treated than in the untreated area, and slightly lower in the Arab nomads than in the others, except that it was markedly lower in females from the West in the treated area. These results are consistent with the known water-contact habits of the two migrant groups. An association was observed between infection and liver and spleen enlargement, but not between infection and other symptoms. The potential importance of migrants in transmitting the infection is discussed.

Portal hypertension and chronic salmonellosis in situs invertus.

The unique combination of a late complication of Schistosoma mansoni infection in situs invertus is reported. The improvement in both the haematological and biochemical indices of the patient after splenectomy is discussed. An association between chronic salmonellosis and schistosomiasis is demonstrated; the experience of the author and other workers with this syndrome is discussed.

Oxamniquine for treating Schistosoma mansoni infection in Sudan.

The efficacy and acceptability of oral oxamniquine were assessed in Sudanese patients infected with Schistosoma mansoni. Cure rates, determined by the absence of viable eggs in the stools six months after treatment, were 94.9% in patients treated with a total of 60 mg/kg, 78.8% in patients treated with 40 mg/kg, and 68.9% in patients treated with 30 mg/kg. All treatment regimens considerably reduced the egg count in those patients not cured. The drug was well tolerated and the side effects were minimal and transient, the most common being dizziness. Most of the patients noticed a reddish discoloration of their urine, which was probably caused by a metabolite of the drug. In patients who received 60 mg/kg oxamniquine there were transient rises in eosinophil counts and in serum alanine aminotransferase concentrations. Though 60 mg/kg was by far the most effective dose in terms of cure rate, egg counts were significantly reduced on all three doses. The lower doses could therefore be useful in a low-cost control programme in reducing transmission of S mansoni infection.

Praziquantel in the treatment of mixed S. haematobium and S. mansoni infections.

A randomized single blind stratified study involving 153 patients with mixed S. mansoni and S. haematobium infection showed that 2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]isoquinolin-4-one (praziquantel, EMBAY 8440, Biltricide) is effective in giving high cure rates in each infection separately, 66% (64 patients) and 77% (94 patients), respectively. The complete clearance of both infections (i.e., no eggs whether dead or alive) 6 months after treatment was 29% (43 patients). The side effects of the drug were minimal and transient, the most common being gastrointestinal ones. The assessment of the objective tolerability by clinical, haematological and biochemical tests showed also that the drug was very safe. It is thus concluded that the drug is a promising useful tool in the control of schistosomiasis in general and the treatment of the individual.

Metrifonate trial in the treatment of various presentations of Schistosoma haematobium and S. mansoni infections in the Sudan.

The effect of metrifonate (Bilarcil Bayer) on Schistosoma haematobium and S. mansoni infections was studied in 174 patients near Khartoum. A high cure rate was obtained in S. haematobium infections, but anthelmintic efficacy was minimal in patients passing S. mansoni eggs in their stools. There was, however, a marked reduction of egg output in patients passing S. mansoni eggs in urine. This suggests that the site of infection in man, rather than the species of parasite, renders the parasite more susceptible to metrifonate. The significance of this and the possibility that these results further clarify the mode of action of metrifonate are discussed.

Clinical diagnosis of cutaneous leishmaniasis (oriental sore).

Cutaneous leishmaniasis (oriental sore) is characterized by slowly evolving inflammatory lesion(s) that are nodular, noduloulcerative, or ulcerative and that heal spontaneously with scar(s) in 3 to 12 months. In the course of a comprehensive study of cutaneous leishmaniasis due to Leishmania major in an endemic focus in Saudi Arabia, seven clinical features of diagnostic value were identified and their approximate frequency in a selected group of 475 patients was determined. These features were: exposed site location, 84%; pairing or clustering of lesions, 61.72%; skin crease orientation, 35.37%; volcanic nodules, 30.32%; satellite papules, 19.37%; subcutaneous nodules, 11.37%; and "iceberg" nodules, 4.63%. This information should serve the process of clinical diagnosis and may be relied upon when the procedures for parasite detection are negative or unavailable.

Infection with Schistosoma mansoni in the Gezire area of the Sudan.

A survey for schistosomiasis in a village in the Gezira area of the Sudan in 1973 showed that there has probably been a great increase in the incidence of S. mansoni infection in the last 25 years. Severe morbidity was uncommon in this sample but overt infection was associated with the symptoms of bloody diarrhoea, tiredness, and possibly abdominal pain, and with a reduced level of haemoglobin. Hepatosplenomegaly was common and schistosomiasis is considered to have contributed to this, although hyperendemic malaria must also have been important in its causation.

Efficacy of metrifonate in urinary schistosomiasis in light and heavy infections.

In a prospective clinical trial, patients with urinary schistosomiasis from the Sudan and from other African countries were treated with two or three doses of metrifonate (10 mg/kg), respectively, in two weeks' intervals. Patients seen in the Sudan (n = 37) were followed up for 3 months, those seen in Hamburg (n = 17) up to 20 months. Each dose of metrifonate led to a decrease of almost 90% in egg excretion independently of the pretreatment intensity of infection so that after three doses a reduction of almost 99.9% was achieved. The estimated proportion of parasitological cure after two doses of metrifonate was in the order of 24% in the lightly infected patients seen in Hamburg, and in the order of 8% in the heavily infected Sudanese patients. Almost 59% of the patients who received a complete metrifonate treatment of three doses stopped to excrete ova of S. haematobium. Drug failure was found in almost the same proportion in the two patient groups (17.5% and 16.2%, respectively) and could not be overcome by additional doses of metrifonate. The considerable reduction in egg excretion after a single dose of metrifonate might have a remarkable benefit in large scale programmes where the aim is drastic reduction of worm burden rather than complete cure.

Zinc and copper status in patients with sickle cell anemia.

Plasma zinc and copper concentrations were determined by atomic absorption spectroscopy in 57 patients with sickle cell anemia and in 45 control subjects from the Eastern Province of Saudi Arabia. Plasma zinc and copper levels in patients were found to be close to those of the control subjects. Similarly, there was a difference neither in urinary zinc level nor in the ratio Cu:Zn in patients and control subjects. This is in contrast to the situation which exists in North American Black subjects with sickle cell anemia, who are known to have zinc deficiency as well as a further decrease in zinc level during sickle cell crises. The near-normal levels of zinc and copper found in Saudi sickle cell patients therefore exclude zinc deficiency and confirm that this population exhibits a milder form of sickle cell anemia.

Dissemination in cutaneous leishmaniasis. I. Subcutaneous nodules.

In a study of cutaneous leishmaniasis (CL) caused by Leishmania major in Saudi Arabia, 10% of the patients were found to have subcutaneous nodules (SCN). The SCNs were usually inconspicuous, painless, and proximal to the primary skin lesions; when multiple, they showed a "sporotrichoid" configuration or appeared as "beaded cords." Their number ranged from 1-16 (average 3 25 +/- 2.50; mean +/- 1 SD). In some patients, the SCNs seemed to be triggered by antileishmanial treatment. The clinical picture and pathologic findings suggest that SCNs in patients with CL represent lymphatic dissemination, a phenomenon not widely recognized.

Dissemination in cutaneous leishmaniasis. 3. Lymph node involvement.

In a study of zoonotic cutaneous leishmaniasis (CL) due to leishmania major in an endemic focus in Saudi Arabia, lymph node enlargement was observed in 66 of 643 patients (10.26%). The epitrochlear lymph nodes were most commonly involved (68%), but cervical (11%), axillary (15%), and inguinal (18%) lymph nodes were also involved. In eight patients (12%), two lymph node areas were involved. The affected lymph nodes were typically solitary, firm, mobile, nontender, only moderately enlarged, and appeared to persist beyond the clinical healing of the associated skin lesions. The results of pathologic and immunopathologic studies carried out on eight lymph nodes obtained from this group of patients supported the leishmanial etiology. Although amastigotes were only demonstrated in two lymph nodes, the leishmanial antigen was found in all eight specimens. The lymph node involvement is another manifestation of dissemination in infection with a dermotropic leishmania. It appears that in some cases, instead of the parasite, it may be the leishmanial antigen that disseminates and produces lymphadenitis.