Fundoscopy would go a long way in saving a number of lives

Malaria, though curable if diagnosed and treated properly, kills one child every 30 seconds. The deadliest form of this disease is cerebral malaria, which is the cause of most malaria deaths in India and some African nations. According to experts, early diagnosis is the key to combating cerebral malaria. However, this is not very easy in children because it is difficult to say with certainty that a comatose child with malaria infection has cerebral malaria.

Addressing this problem, researchers have come up with a simple and cost-effective diagnostic measure for cerebral malaria. Dr Nicholas Beare of St Paul’s Eye Unit, Liverpool, and his associates have shown cerebral malaria in unconscious children can be easily detected by examining the eyes, using an ophthalmoscope. By looking at the changes in the retina (light-sensitive tissue at the back of the eye), doctors can say whether an unconscious child is suffering from cerebral malaria or some other condition. This can greatly help to provide appropriate treatment at the right time, especially in certain developing countries where malaria is rampant. The study has been published in the November issue of the American Journal of Tropical Medicine and Hygiene.

“Cerebral malaria is a severe consequence of falciparum malaria (malaria caused by Plasmodium falciparum),” says US public health expert Dr Lawrence Barat, senior technical advisor at the Global Health, Population, and Nutrition Group Academy for Educational Development, Washington. “Its symptoms generally are either lethargy progressing to coma or recurrent seizures. It occurs most commonly when falciparum malaria goes untreated for more than 24-48 hours or if incorrect or insufficient treatment is given,” he says. “The mechanism by which cerebral malaria occurs is still a topic of debate, but autopsies of people who have died of this disease reveal malarial parasites sticking to the walls of the blood vessels in the brain,” he explains.

The disease leads to certain changes in the retina — collectively called malarial retinopathy — such as formation of white, opaque patches, whitening of the retinal blood vessels, bleeding and swelling of the optic nerve. “These are due to hemodynamic (pertaining to blood circulation movements) and cerebral changes caused by the disease process… Ocular findings correlate to the severity of the disease,” says Dr Nazimul Hussain, consultant ophthalmologist affiliated to the L.V. Prasad Eye Institute, Hyderabad.

“Besides, there may be fluid collection or opacification of the retina owing to the closure of capillaries,” says Prof. Amod Gupta of the Post Graduate Institute of Medical Education and Research, Chandigarh. “The changes may be due to anaemia or parasite-laden red blood cells trapped in the microvasculature (part of the circulatory system consisting of very small blood vessels) of the retina and brain,” he adds.

Dr Beare and his team studied 45 African children in Malawi in southeastern Africa to arrive at the conclusion that cerebral malaria can be diagnosed by noting the changes in the retina. “The eye acts as a window to the brain; if malarial retinopathy is absent in a child thought to have cerebral malaria, other causes of coma should be investigated. However, we would not advocate stopping malaria treatment just on that basis,” Dr Beare told KnowHOW. In adults, kidneys, liver and lungs can also be severely affected. “Severe malaria is treated with intravenous quinine, anti convulsants and fluids. Blood transfusion may also be required. The treatment for mild malaria is different,” he says.

“Quinine is the standard therapy, but artemisinin derivatives (such as artemether) have been shown to act more rapidly than quinine,” adds Dr Barat.

Cerebral malaria is a major problem in India. According to researchers at Shri Vasantrao Naik Government Medical College, Yavatmal, Maharashtra, it is seen in approximately 32 per cent of Plasmodium falciparum positive cases. Their study, which focused on 2,991 children from rural areas and was published in the Indian Journal of Pediatrics, concludes, “Probable cerebral malaria is an entity that should be kept in mind while treating fever without definite focus, especially in the rural areas.”

Another study by researchers at M.K.C.G. Medical College and Hospital, Berhampur, also points out that cerebral malaria is the commonest cause of mortality in children with a complicated or severe form of falciparum malaria.

Dr Nikunj Shah, retinal surgeon and founder of The Eye Super Specialities (TESS), Mumbai, says, “If we could do a simple test like fundoscopy (examination of the fundus — the part of the eye opposite the pupil — by an ophthalmoscope), which is non invasive, handy and cheap, it would go a long way in saving a number of lives.”

In this regard, Dr Beare’s study is impressive, say experts, the only problem being the possibility of misdiagnosis. However, this can be overcome by special training in eye examination for the diagnosis of cerebral malaria, says the Liverpool doctor.