Severe anaemia is not associated with HIV-1 env gene characteristics in Malawian children

Severe anemia in Papua New Guinean children from a malaria-endemic area: a case-control etiologic study

BACKGROUND

There are few detailed etiologic studies of severe anemia in children from malaria-endemic areas and none in those countries with holoendemic transmission of multiple Plasmodium species.

METHODOLOGY/PRINCIPAL FINDINGS

We examined associates of severe anemia in 143 well-characterized Papua New Guinean (PNG) children aged 0.5-10 years with hemoglobin concentration <50 g/L (median [inter-quartile range] 39 [33]-[44] g/L) and 120 matched healthy children (113 [107-119] g/L) in a case-control cross-sectional study. A range of socio-demographic, behavioural, anthropometric, clinical and laboratory (including genetic) variables were incorporated in multivariate models with severe anemia as dependent variable. Consistent with a likely trophic effect of chloroquine or amodiaquine on parvovirus B19 (B19V) replication, B19V PCR/IgM positivity had the highest odds ratio (95% confidence interval) of 75.8 (15.4-526), followed by P. falciparum infection (19.4 (6.7-62.6)), vitamin A deficiency (13.5 (5.4-37.7)), body mass index-for-age z-score <2.0 (8.4 (2.7-27.0)) and incomplete vaccination (2.94 (1.3-7.2)). P. vivax infection was inversely associated (0.12 (0.02-0.47), reflecting early acquisition of immunity and/or a lack of reticulocytes for parasite invasion. After imputation of missing data, iron deficiency was a weak positive predictor (6.4% of population attributable risk).

CONCLUSIONS/SIGNIFICANCE

These data show that severe anemia is multifactorial in PNG children, strongly associated with under-nutrition and certain common infections, and potentially preventable through vitamin A supplementation and improved nutrition, completion of vaccination schedules, and intermittent preventive antimalarial treatment using non-chloroquine/amodiaquine-based regimens.

[Frequency of severe anemia in children aged 2 months to 15 years at Mother and Child Centre of the Chantal Biya Foundation Yaounde, Cameroon]

Introduction

Les anémies sévères constituent une cause importante de décès d’enfants. Une analyse épidémiologique et clinique permettrait d’estimer la morbidité et mortalité y relatives afin lutter efficacement contre les causes.

Méthodes

Notre étude rétrospective et descriptive porte sur les anémies sévères chez les enfants de 2 mois à 15 ans de juillet 2005 à juillet 2011. Les drépanocytaires et les enfants souffrant de néoplasie étaient exclus. Toutes les admissions de janvier 2008 à juillet 2011 et les décès totaux, qui répondaient aux critères ci-dessus ont été également répertoriés.

Résultats

Ont été analysés 4735 cas d’anémie sévère dont 215 décès (4,5%). Entre janvier 2008 et juillet 2011, sur 12879 enfants hospitalisés 2456 souffraient d’anémie sévère dont 96 sont décédés, soit une mortalité spécifique de 0,7% et une létalité de 4,0%. Au total, 22,4% d’anémies sévères survenaient dans la tranche d’âge de moins de 12 mois. Celles de 12 à 59 mois et de plus de 5 ans représentaient respectivement 64,4% et 13,2% des cas. Le paludisme était l’étiologie évoquée chez 89,0% des cas, suivi du sepsis (9,4%). Les décès concernaient les enfants sévèrement anémiés âgés de 12 à 59 mois dans 67,2% de cas. La plupart de patients (84,8%) résidaient à Yaoundé (P = 0,004).

Conclusion

Les anémies sévères restent fréquentes à Yaoundé. La mise en œuvre de da politique de gratuité des antipaludiques et l’utilisation des moustiquaires doivent être effectives. Le renforcement de ces mesures dès le début des saisons pluvieuses préviendrait les flambées d’anémies.

Severe acquired anaemia in Africa: new concepts

Severe anaemia is common in Africa. It has a high mortality and particularly affects young children and pregnant women. Recent research provides new insights into the mechanisms and causes of severe acquired anaemia and overturns accepted dogma. Deficiencies of vitamin B12 and vitamin A, but not of iron or folic acid, are associated with severe anaemia. Bacterial infections and, in very young children, hookworm infections are also common in severe anaemia. Irrespective of the aetiology, the mechanism causing severe anaemia is often red cell production failure. Severe anaemia in Africa is therefore a complex multi-factorial syndrome, which, even in an individual patient, is unlikely to be amenable to a single intervention. Policies and practices concerning anaemia diagnosis, treatment and prevention need to be substantially revised if we are to make a significant impact on the huge burden of severe anaemia in Africa.

Lack of detection of XMRV in seminal plasma from HIV-1 infected men in The Netherlands

Background

Xenotropic murine leukaemia virus-related virus (XMRV) is a recently discovered human gammaretrovirus with yet unknown prevalence and transmission route(s). Its presence in prostate stromal fibroblasts and prostatic secretions suggests that XMRV might be sexually transmitted. We chose to study a compartment closely connected to the prostate, a location where XMRV was detected in independent studies. Seminal plasma samples from HIV-1 infected men were examined as they have an increased probability of acquiring sexually transmitted pathogens.

Methodology/Principal Findings

We studied the prevalence of XMRV in 93 seminal plasma samples of 54 HIV-1 infected men living in The Netherlands with a nested PCR amplification specifically targeting the XMRV gag gene. As a control for the presence and integrity of retrovirus particles, HIV-1 was amplified from the same samples with a PCR amplification targeting the env gene of the virus, or HIV-1 was quantified with a real-time PCR amplifying part of the pol gene.

Conclusions/Significance

Although HIV-1 was amplified from 25% of the seminal plasma samples, no XMRV was detected, suggesting that either the prevalence of XMRV is very low in The Netherlands, or that XMRV is not naturally present in the seminal plasma.