Severe anemia in Malawian children.
BACKGROUND
Severe anemia is a major cause of sickness and death in African children, yet the causes of anemia in this population have been inadequately studied.


METHODS
We conducted a case-control study of 381 preschool children with severe anemia (hemoglobin concentration, <5.0 g per deciliter) and 757 preschool children without severe anemia in urban and rural settings in Malawi. Causal factors previously associated with severe anemia were studied. The data were examined by multivariate analysis and structural equation modeling.


RESULTS
Bacteremia (adjusted odds ratio, 5.3; 95% confidence interval [CI], 2.6 to 10.9), malaria (adjusted odds ratio, 2.3; 95% CI, 1.6 to 3.3), hookworm (adjusted odds ratio, 4.8; 95% CI, 2.0 to 11.8), human immunodeficiency virus infection (adjusted odds ratio, 2.0; 95% CI, 1.0 to 3.8), the G6PD(-202/-376) genetic disorder (adjusted odds ratio, 2.4; 95% CI, 1.3 to 4.4), vitamin A deficiency (adjusted odds ratio, 2.8; 95% CI, 1.3 to 5.8), and vitamin B12 deficiency (adjusted odds ratio, 2.2; 95% CI, 1.4 to 3.6) were associated with severe anemia. Folate deficiency, sickle cell disease, and laboratory signs of an abnormal inflammatory response were uncommon. Iron deficiency was not prevalent in case patients (adjusted odds ratio, 0.37; 95% CI, 0.22 to 0.60) and was negatively associated with bacteremia. Malaria was associated with severe anemia in the urban site (with seasonal transmission) but not in the rural site (where malaria was holoendemic). Seventy-six percent of hookworm infections were found in children under 2 years of age.


CONCLUSIONS
There are multiple causes of severe anemia in Malawian preschool children, but folate and iron deficiencies are not prominent among them. Even in the presence of malaria parasites, additional or alternative causes of severe anemia should be considered.
Calis
Job C J
JC
Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, Blantyre, Malawi. job.calis@gmail.com
Phiri
Kamija S
KS
Faragher
E Brian
EB
Brabin
Bernard J
BJ
Bates
Imelda
I
Cuevas
Luis E
LE
de Haan
Rob J
RJ
Phiri
Ajib I
AI
Malange
Pelani
P
Khoka
Mirriam
M
Hulshof
Paul J M
PJ
van Lieshout
Lisette
L
Beld
Marcel G H M
MG
Teo
Yik Y
YY
Rockett
Kirk A
KA
Richardson
Anna
A
Kwiatkowski
Dominic P
DP
Molyneux
Malcolm E
ME
van Hensbroek
Michaël Boele
MB
D000740:Anemia / Q000145:classification / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics; D018798:Anemia, Iron-Deficiency / Q000453:epidemiology; D016470:Bacteremia / Q000150:complications / Q000453:epidemiology; D016022:Case-Control Studies; D015984:Causality; D002675:Child, Preschool; D005260:Female; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics; D015658:HIV Infections / Q000150:complications / Q000453:epidemiology; D006725:Hookworm Infections / Q000150:complications / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008288:Malaria / Q000150:complications / Q000453:epidemiology; D008295:Malawi / Q000453:epidemiology; D008297:Male; D015999:Multivariate Analysis; D009748:Nutrition Disorders / Q000150:complications / Q000453:epidemiology; D016017:Odds Ratio; D012720:Severity of Illness Index
D005954:Glucosephosphate Dehydrogenase