Carboxyhemoglobin levels in Kenyan children with Plasmodium falciparum malaria

Aubrey J Cunnington1, Stuart F W Kendrick, Betty Wamola

  • 1Department of Paediatrics, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, United Kingdom. acunning@doctors.org.uk

Heme oxygenase (HO) is thought to be induced in severe malaria, but the pathophysiologic consequences have not been examined. It is induced by hemolysis, oxidative stress, and inflammation. It degrades heme, producing carbon monoxide (CO), which causes elevated levels of carboxyhemoglobin (COHb). In a prospective study of 1,520 children admitted to a Kenyan district hospital, COHb levels were no higher in children with malaria than with other infections. The COHb levels in children with severe malarial anemia were higher than in other children with malaria, but significantly lower than in children with other causes of severe anemia such as sickle cell disease. Levels of COHb were not significantly higher in children with cerebral malaria or in those dying of malaria. These results do not support a systemic increase in HO activity in malaria compared with other infectious diseases, but the roles of HO and CO in malaria require further study.

Related Concept Videos

Malaria01:29

Malaria

Malaria pathogenesis in humans reflects a delicate interplay between parasite biology and host response. Clinical illness reflects a host’s immune response to the parasite’s asexual replication cycle, which is often asymptomatic in individuals with partial immunity. From the parasite's perspective, transmission between mosquito and human with minimal host pathology is evolutionarily advantageous. Among the six Plasmodium species infecting humans, P. falciparum and P. vivax dominate in global...
Oxygen Transport in the Blood01:27

Oxygen Transport in the Blood

Hemoglobin (Hb) is a crucial molecule in the human body, consisting of four polypeptide chains, each bound to an iron-containing heme group. This unique structure enables hemoglobin to bind to oxygen, with each molecule capable of combining with four molecules of oxygen, leading to rapid and reversible oxygen loading. When fully loaded with oxygen, it is called oxyhemoglobin, while hemoglobin that has released oxygen is called reduced hemoglobin or deoxyhemoglobin. As hemoglobin binds oxygen,...
Hemoglobin01:24

Hemoglobin

Hemoglobin is a globular protein made up of four subunits. Two of these subunits are alpha chains, and the other two are beta chains. Each subunit contains a molecule of heme, which has an iron atom and can bind to oxygen. When an oxygen molecule binds to one heme group, it changes the shape of hemoglobin, making it easier for the other heme groups to bind oxygen as well.
When all four heme groups are bound to oxygen, the resulting molecule is called oxyhemoglobin. As a result, arterial blood...