Placental malaria. I. Pathological classification

Pregnant women are more likely to contract malaria than their non-pregnant counterparts. The aim of this study was to develop a simple classification system for the histopathological diagnosis of placental malaria infection applicable to placentas collected in field conditions. The placentas were classified into four groups depending on the presence and disribution of parasites and malaria pigment: active infection, active-chronic infection, past-chronic infection, not infected. The frequency of parasitized placentas (26.4%) was in keeping with the prevalence of placental parasitaemia documented in epidemiological studies. An additional 29.8% placentas showed pigment in fibrin only, indicating pastchronic infection. Chronic placental malaria infection was most common in primigravidae, possibly reflecting ineffective clearance of parasites from the placenta. Seasonal fluctuations between infection categories support progression of placental infection with delayed clearance of pigment from fibrin. The proposed classification system has allowed diagnosis of different categories of placental malaria infection by two independent observers. A stadardized method of diagnosis may enhance understanding of placental pathology and reduced birth weight in malaria infection during pregnancy.     

Eosinophilia and resistance to Schistosoma haematobium in man

We have measured the levels of infection with Schistosoma haematobium in children resident in an endemic area of The Gambia before and 3 months after successful chemotherapy and following reinfection. An exposure index was calculated from data collected on water contact, cercarial densities and infected snail densities at water contact sites. Peripheral blood eosinophil levels were recorded and the ability of serum (heat inactivated) from the children to allow killing of schistosomula of S. haematobium was examined. Of 50 children with a post-treatment egg count of less than 1 ovum/10 ml urine, 26 were classified as reinfected, acquiring greater than 1 ovum/10 ml urine over the transmission season. Twenty-four were classified as not reinfected, acquiring less than 1 ovum/10 ml of urine over the same period. These two groups did not differ with respect to their estimated age, weight or pretreatment egg counts. Children who were reinfected had significantly higher levels of exposure and significantly lower peripheral blood eosinophil counts than children who were not reinfected. At all levels of exposure children with high eosinophil counts were less likely to be reinfected than those with lower counts. But antibody-dependent, complement-independent killing of schistosomula of S. haematobium by eosinophils was barely detectable and did not differ between reinfected and non reinfected groups. These observations suggest that subjects with elevated counts are less susceptible to reinfection but the mechanisms involved are not apparent.     

Humoral immune responses in Gambians to Pfs16, an immunodominant, Plasmodium falciparum integral membrane protein

Naturally acquired humoral immune responses to Pfs16, an integral membrane protein expressed in Plasmodium falciparum gametocytes and sporozoites, were investigated in The Gambia. A high prevalence of antibodies to this molecule was detected by peptide ELISA. Ninety-three per cent of the people taking part in a survey at the end of the rainy season (November) had serum antibodies to one or more synthetic peptides spanning the sequence; 88% reacted with one particular peptide sequence (IMLIILSGIVGFKVK) whereas only one out of ten non-Gambians (taking anti-malarial prophylaxis with no history of infection) reacted with the peptide. Epitope mapping with mouse MoAbs has shown that this peptide is located on a part of the molecule differing from immunodominant regions of the molecule identified in a previous study in Papua New Guinea.     

Effect of epidural analgesia on maximum and minimum blood pressures during the first stage of labour in primigravidae with mild/moderate gestational hypertension

Summary. One of the arguments used in favour of epidural analgesia for hypertensive patients in labour is its effect on mean arterial blood pressure, although the fetal and maternal risk from hypertension is more closely linked to maximum recorded levels. We have therefore assessed the effect of epidural analgesia on maximum blood pressure. There was no change in the maximum systolic or diastolic blood pressure after epidural analgesia when compared to baseline values or levels in untreated hypertensive controls. We conclude that this form of analgesia should be offered to hypertensive patients purely for its analgesic effect and not as a method for blood pressure control.     

Serum immunoglobulins in Nigerian patients with lichen planus

In a group of 42 African patients with lichen planus, a significant lowering of circulating IgM was found.     

Clinical investigation of agents with prophylactic anti-allergic effects in bronchial asthma*

To determine the efficacy of ketotifen as an oral anti-asthmatic agent, experimental and therapeutic long-term trials were carried out. Four models were used in the experimental therapeutic trials and the antihislaminic agent clemastine and disodium cromoglycate were used as comparative substances. It was demonstrated that ketotifen provides protection against bronchospasm induced by allergens, histamine and exercise, but not against that induced by acetylcholine. In the therapeutic long-term trials, the efficacy and tolerance of ketotifen were compared with that of clemastine and disodium cromoglycate for a period of 6 months. In another study ketotifen was administered for 1 year, Ketotifen proved very effective in decreasing the frequency and duration of asthmatic attacks, concomitant medication could be reduced and the patients improved subjectively. From these trials it can be concluded that ketotifen is a safe and effective oral anti-anaphylactic agent for use in the long-term treatment of bronchial asthma.     

Using a Teaching Guide for Better Postpartum and Infant Care

The development and use of a guide for postpartum and infant care teaching is discussed, including the rationale, methods, and advantages of using this tool at two hospitals of different sizes. Also discussed are the preparation of personnel, ongoing development, and extended uses of the guide.