Tropical and geographical medicine最新文献

Pityriasis versicolor is a superficial fungal infection of the skin caused by Malassezia furfur (Pityrosporum orbiculare) which is a part of the normal flora of the human skin. The factors which govern the pathogenic conversion of this fungus are not fully understood but a hot humid environment is considered to be a predisposing factor and the disease is very common in tropical countries. Clinically the disease is characterized by scaly hypo- or hyperpigmented macular lesions that are typically located in the trunk, neck and upper arms. The penis is rarely affected. In this report a patient of pityriasis versicolor with involvement of the shaft of the penis is presented.

Visceral leishmaniasis (VL), caused by Leishmania donovani, is endemic in Baringo District, Kenya. The disease has a focal distribution in the dry, hot areas below 1500 metres. Infections may be characterized as follows: 1) asymptomatic, 2) subclinical and self-limiting (not medically identifiable), and 3) clinically manifest disease (that is medically identifiable). Half of the reported VL patients are between 5 and 14 years of age and 66% of them are males. The reasons for the focal distribution and for the age and sex preference are discussed. Phlebotomus martini is the vector of the parasite, and man is the only known reservoir. Cutaneous leishmaniasis (CL), due to Leishmania major, is rare in humans, but underreporting is likely. The vector, Phlebotomus duboscqui, is mainly found in animal burrows where it feeds on rodents which are frequently infected. A human case of a mixed L. donovani and L. major infected. A human case of a mixed L. donovani and L. major infection has been reported in this dual focus of VL and CL.

Twenty-eight (42%) of 67 afebrile children (mean age 6.3 +/- 3.6 years) undergoing various minor elective surgeries were slide positive for malaria parasitaemia. All infected subjects were given oral chloroquine therapy before and after blood samples were collected. Pre- and post-treatment complement (C4, C3, Bf and CH50 levels were evaluated in 15 of the subjects who had parasite densities > or = 500/microliter. These were compared with the levels in 15 age/sex-matched children who had acute malaria, as well as with the levels in 15 age/sex matched, non-infected controls. Significant consumption of C4 was observed in both the asymptomatic (p < 0.05) and symptomatic (p < 0.05) subjects. The mean serum levels of C4 were significantly higher in the asymptomatic, when compared with the symptomatic subjects (p < 0.01), and the healthy controls (p < 0.05). The distribution of classical pathway complement haemolytic titres in the groups studied was the same as that of the C4 levels. It is concluded that the forth component of the classical complement pathway may play a protective role in asymptomatic malaria.

The possible influence of maternal malaria prophylaxis on infancy malaria was assessed in 241 infants. Mothers of 91 infants (PROG-cohort), 99 infants (CQ-cohort) and 51 infants (CQ+PROG-cohort) had received prophylaxis with daily proguanil, once weekly chloroquine, and the two drug combination respectively. Blood smears of infants were examined for parasitaemia once fortnightly. Parasitaemias were treated with either amodiaquine, Fansidar, or Fansidar-quinine combination. In all cohorts, the incidence of malaria parasitaemias within 3 months of age was high (overall mean = 63%). Chloroquine released from its tissue bound form in the CQ and CQ+PROG-cohorts did not have significant chemosuppressive effects on the parasitaemias. Acknowledging that the CQ-prophylaxis group simulated the hypothetical control group, the cohorts similarity in the pattern of parasitaemias suggested that effective maternal malaria chemoprophylaxis during pregnancy did not significantly influence infancy malaria. A sharp rise in incidence around 3 months was indicative of the waning effect of passive immunity. Sole dependence on sub-optimal active immunity led to another sharp rise in incidence from 9 months onwards. The high incidence of infancy malaria parasitaemias calls for increased vigilance in their early detection and effective treatment. Social-cultural factors within the communities may constrain effective disease management.

The objective of this study was to measure perinatal mortality rate (PMR), percentage of low birth weight (LBW) and twinning rate, as obtained from a prospective community-based survey and hospital data. The community survey was performed in five villages in North-western Tanzania recruiting 447 pregnant women, while the study in the local District Hospital included 3,056 hospital deliveries. PMR was 68/1,000 in the community survey and 96/1,000 births in hospital. Stillbirths accounted for 81% of perinatal mortality in hospital as compared to 41% in the community-based survey. Percentages of LBW were 9.9 and 14.6 and twinning rates were 14/1,000 and 39/1,000 births in the community study and hospital, respectively. Perinatal mortality, low birth weight and twinning rates in hospital were higher than in the community survey. Estimations of perinatal outcome in hospital cannot be extrapolated to the community concerned.

The birthweight and mortality in hospital was recorded of 567 low birth weight (LBW, < or = 2000 g) infants born/admitted during a 7 years period in Agogo Hospital situated in the rainforest area of Ghana. One hundred and fifty-two (26.8%) of these children died in hospital; 87 (57%) of them in the first 48 hours. The average length of stay in hospital of the surviving children was 11.6 days. The death rate varied from 8.4% in the 1,751 to 2,000 g group to 83.3% in infants with a birth weight < or = 1000 g. The proportion LBW children to the total newborn population was 5.5%; the proportion of extreme LBW (< or = 1000 g) to the total number LBW infants was 7.3%. The results are compared with figures from other countries, many of them with a more westernized infrastructure. In our setting, no sophisticated equipment and expensive intensive care provisions were available. This descriptive study was carried out to establish the survival rate in the neonatal period during the primary stay in hospital with low-cost conservative care. Dedicated staff members, who underwent only a simple training programme, and mothers participating in the care for their children contributed to the relatively favourable outcome.

A cross-sectional survey was carried out to investigate the pattern of plasma lipid concentrations of healthy Nigerians living in the urban area of Lagos. Generally, the levels of plasma total cholesterol, triglyceride and lipoproteins of Africans were lower than those of Caucasians. The subjects were on high carbohydrate and low fat diets, and most of them were involved in some form of physical activity. These factors might contribute to their low plasma lipid levels. The plasma lipid concentrations (except HDL-cholesterol) increased with age. However, the HDL-cholesterol values remained very high within the protective limits, in older individuals as well as younger subjects. There were no significant differences in the cholesterol and triglyceride values for male and female subjects. Finally, the overweight subjects had higher concentrations of plasma lipids than subjects with normal weights.

Trichomonas vaginalis was diagnosed in 42 (19%) of 227 adult males with urethral discharge. In 27 men (15%) T. vaginalis was isolated together with Neisseria gonorrhoeae. Non-gonococcal urethritis was diagnosed in 15 patients and T. vaginalis was isolated from 47% of such patients. Stained smear preparations, i.e. RapiDiff and acridine orange of modified Diamond's media, were superior to wet smear microscopy for the identification of T. vaginalis. RapiDiff stain was the most sensitive and identified 41 of 42 (98%) positive cultures. It is recommended that all turbid culture media should be stained for the optimal diagnosis of trichomoniasis.

The pattern of morbidity and mortality of 103 neonates weighing less than 2500 g referred to a Nigerian University Teaching Hospital over a period of 30 months (March 1989-August 1991) was studied. Fifty seven (55.3%) weighted less than 1500 g, 80 (77.7%) were preterm while 23 (22.3%) were term, small for gestation. Sepsis, hypothermia, respiratory distress syndrome and birth asphyxia were the commonest problems encountered. These were also the predominant associated causes of death. The corrected mortality rate was 65.3%, the rate being higher for babies weighing less than 1500 g (chi 2 = 4.02, p < 0.05) and for small for gestational age babies (chi 2 = 5.17, p < 0.025). The early neonatal problems stemmed from suboptimal conditions of perinatal resuscitation, thermoregulation and transfer. High mortality was also caused by poor state of facilities at the referral centre. Early materno-foetal transfer during preterm labour to hospitals with facilities for optimal perinatal care would reduce morbidity and mortality.