Sickle cell anaemia deaths are ‘avoidable’ — study

Children born with sickle cell anaemia in the region — and probably across sub-Saharan Africa — are dying in their thousands because their weak immune systems cannot fight off bacterial infections, a Kenyan study has established.

The study, the largest of its kind ever to be conducted in the world, and whose results have been published in the respected journal Lancet, recommends that newborns be screened for sickle cell anaemia, and those found to have the condition to be immunised against common infections.

Whenever such children report to hospitals, the study says, they should also receive special care.

“This study will make a huge difference to the way my ministry thinks about sickle cell disease,” said Dr S. K. Sharif, Kenya’s Director of Public Health and Sanitation.

Sickle cell anaemia affects millions of people worldwide but more than 80 per cent of cases are in Africa where an estimated 200,000 children are born with the condition every year.

The inherited disease manifests in the formation of abnormal, sickle-shaped red blood cells. Normal cells are round.

Abnormal sickle cells cause complications because they do not pass easily through blood vessels, and can form clusters which block the flow of blood to limbs and organs leading to pain, infections and organ damage.

The Kenyan study, which involved researchers from the the Kenya Medical Research Institute (Kemri)-Wellcome Trust Programme in the coastal district of Kilifi studied blood samples from all children aged under 14 who were admitted to the local hospital during a ten year period between 1998-2008.

The researchers screened the samples for cases of infections and then tested the positive samples for sickle cell anaemia.

From 40,000 admissions to the hospital, the Lancet report says, the researchers identified more than 2,000 cases of infections with various bacteria.

When the infected children’s blood was screened for sickle cell anaemia, it was established that the prevalence of the condition was more than 20 times than in the general population, which stands at less than three in every 1,000 children.

This, the researchers concluded, showed that sickle cell anaemia considerably raises the risks of infections.

The most common bacterial infections in the children with sickle cell anaemia were caused by an organism called Streptococcus pneumoniae, which accounted for 41 per cent of cases, and Haemophilus influenzae type b, which was responsible for 12 per cent of infections.

Both organisms cause serious infections that may lead to life-threatening pneumonia or meningitis. However, they are both preventable by vaccination.

Significantly, the researchers involved in the study now estimate that in Kilifi, it is likely that up to one quarter of all child-deaths are attributable to sickle cell anaemia, with bacterial infections accounting for a sizable proportion.