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Massive chronic intervillositis (MCI) is an infrequently recognized placental lesion thought to be of immunologic origin that has been associated with poor fetal outcome. It is characterized by a prominent inflammatory infiltrate in the intervillous space, composed mainly of monocytes and macrophages that can simulate a maternal malignant disorder involving the placenta. The villi are characteristically spared. We report 74 cases of placental malarial infection with morphologic features of MCI. In all cases, the massive inflammatory infiltrate was limited to the intervillous space, which appeared largely obliterated. Increased fibrin deposition and prominent syncytial knots were frequent associated findings. Inflammatory cells were CD45 and CD68 positive, consistent with a monocyte-macrophage population. Some polymorphonuclear leukocytes and scattered T and B lymphocytes were also present. Villi were not inflamed. Malarial pigment was present in all cases, and parasitized maternal erythrocytes were evident in 73 of 74 patients. The histologic pattern of MCI was observed in 17.6% of placentas with malarial parasites. Malarial MCI affected predominantly primigravida women (77%) and was associated with a reduced birth weight, which in 39 (53%) of the infants was less than 2500 g, and a low gestational age. None of the infants with placentas with MCI died in the early neonatal period. Morphologic changes of MCI are seen in a significant percentage of placentas with malarial infection, especially in primigravida women, and are associated with a low birth weight. Malarial infection should therefore be considered in the differential diagnosis of massive intervillous infiltrates.

Summaryintroduction Anaemia is the most frequent haematological disorder in childhood. The notion that defines naemia does not change throughout life, although parameters used for its evaluation show significant variations during childhood. Haematocrit (Hct) (%) is usually defined as three times the value of haemoglobin (Hgb) (g/dl), while the clinical definition of anaemia is related to either an abnormal Hct or Hgb value.objective To evaluate the agreement between Hgb and Hct values in the definition of anaemia, the relationship between these two parameters and their age-dependence.methods The Hct and Hgb paired values from children aged 2-18 months from Ifakara (Tanzania) and children aged 1-4 years from Manhiça (Mozambique) were analysed. Haematological determinations of the Manhiça samples were done using a KX-21N cell counter (Kobe, Japan) and Ifakara samples were analysed in a semiautomatic cell counter (Sysmex F800 microcell counter, TOA Medical Electronics, Kobe, Japan). The j-statistic was used to calculate the agreement between anaemia definitions in each group. Crude and multivariate relationship between Hct and Hgb levels were analysed by linear regression model estimation. The age-dependence of the crude ratio (Hct/Hgb) was analysed using linear regression models and fractional polynomials.results The prevalences of mild and moderate anaemia as defined by Hgb levels in the Manhiça group were 61% and 6%, respectively, and 41% and 2% by Hct. In the Ifakara group these were 74% and 10%, respectively, by Hgb and 42% and 3% by Hct, respectively. Agreement between mild and moderate anaemia definitions made up from Hgb or from Hct levels were from fair to moderate. Hct levels decreased with age for high Hgb levels, whereas they increased for low Hgb levels. The classification of cases is improved when higher age-related cut-off values for Hct are used. The crude relationship between Hct and Hgb levels was significantly different from 3, and this was modified by age. The evaluation of the age-dependence ratio (Hct/Hgb) showed a non-linear relationship with an asymptotic trend to 3.

During a randomized placebo-controlled trial of chemoprophylaxis against Plasmodium falciparum malaria and iron supplementation, in infants living under conditions of intense transmission, all samples of I? fazciparum obtained from children aged 5 and 8 months were genotyped by polymerase chain reactionrestriction fragment length polymorphism analysis for the msp2 locus. One hundred and six blood samples were analysed for the number of concurrent infections (multiplicity), and the allelic family of each msp2 genotype was determined. Mean multiplicity of infection was, overall, 2.76 infections/child, and it was significantly reduced in infants receiving chemoprophylaxis. This finding might help to explain the rebound effect in morbidity observed after prophylaxis was ended. Iron supplementation did not affect multiplicity of infection. In infants receiving placebo only, or placebo and iron supplementation, a significant positive association was observed between the number of infections and parasite densities (Spearman's p=O.25, P-0.047). This association was lost in the group receiving chemoprophylaxis alone, or in combination with iron. This study showed a significant association of FC27-like msp2 alleles with prospective risk of clinical malaria in children (relative risk=l.487, eO.013). Such an association was also found for the present risk of clinical malaria in infants receiving prophylaxis (odds ratio=3.84, P=O.O26), which might imply that chemoprophylaxis may impair the development of premunition.

A randomized study on the in vivo efficacies of chloroquine and a pyrimethamine-dapsone combination (Maloprim) in clearing P. fulcipurum parasitaemia was carried out in 77 asymptomatic semi-immune schoolchildren in the Kilombero District of Tanzania. Children were randomized to receive either chloroquine at a dose of 25 mg/kg over three days, or Maloprim (6.2s mg pyrimethaniine+so mg dapsone for children under L O years, and 12. j mg pyrimethamine+ TOO mg dapsone for children T O or more years old) as a single dose. Children were followed-up for malaria parasitaemia at days 2, 7 and 14 after screening, randomization and treatment. The slide positivity rate was lower in the Maloprim group a t all cross-sectional surveys (23 us 37% at day 2; 9 us LO% at day 7; 21 us 32% at day 14) but none of these differences reached statistical significance. No cases in the Maloprim group showed RII resistance, whereas in the chloroquine group, z cases showed RII resistance and a further L cases RIII resistance ( 6 % ) . No major side-effects were reported. The combination of pyrimethamine-dapsone appears to he a better choice than chloroquine as a chemoprophylactic regimen for malaria in this area. Although they need to be confirmed in a larger study, these results may be of interest to the policy-makers as well as researchers. keywords pyrimethamine-dapsone, malaria, efficacy, schoolchildren