What Is Malaria?
Malaria is a life threatening disease caused by Plasmodium parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. In the early stages, the symptoms of malaria may be similar to other bacterial or viral illnesses.
In rare cases, malaria can impair the functioning of all the vital organs of the body, leading to multi-organ failure. Severe falciparum malaria is defined as the involvement of one or more organs (impaired consciousness, convulsions, renal impairment, jaundice, pulmonary edema, significant bleeding, shock) along with falciparum parasitemia >10 %. Severe vivax malaria is similar to falciparum, but there are no parasite density thresholds. Severe knowlesi malaria is also similar to falciparum but the parasite density is 1%.
Cerebral malaria may be the most common non-traumatic encephalopathy in the world. Cerebral malaria is the most severe complication of Plasmodium falciparum infection and may present with progressive delirium, seizures, and coma and can lead to serious consequences.
Incidence:
Approximately 4.5 lakh deaths are caused by malaria each year, with over 90% of fatalities occurring among children. According to WHO P.falciparum accounted for 99.7% of estimated malaria cases in the WHO African Region, 50% of cases in the WHO South-East Asia Region, 71% of cases in the Eastern Mediterranean, and 65% in the Western Pacific. P.vivax accounted for 75% of malaria cases in the United States.
Case Report:
We present a case of cerebral malaria in an adult after a recent three week travel to a malaria-endemic country Africa. A 53 year old male was admitted to the intensive care unit with high grade fever, acute confusional state, and irrelevant talk. On presentation, he was tachycardic, febrile, and encephalopathic with labs notable for thrombocytopenia, and elevated liver function tests. A peripheral smear for Malaria test was positive for Plasmodium vivax species. MRI brain on admission was normal.
He was diagnosed with severe complicated cerebral P.vivax malaria. Treatment was initiated immediately with antimalarial Artesunate therapy. Despite the treatment given, he continued to worsen, his blood pressure was persistently low, his consciousness levels dropped, and he developed worsening breathing difficulty that required mechanical ventilatory support. His consequent blood reports revealed an acute kidney injury requiring hemodialysis, and his repeat MRI brain scans showed diffuse cerebral edema. He also developed a concomitant infection in his lungs. He was started on appropriate antibiotics and brain anti-edema measures.
Over the next few days, his clinical condition deteriorated, and remained ventilator dependent, requiring high oxygen support. He underwent a tracheostomy in view of the prolonged need for invasive ventilatory support.
After two weeks of intensive care, he gradually showed signs of improvement in his consciousness and respiratory parameters. However, there was no significant improvement in his renal parameters and he required alternate day dialysis. Almost three weeks after hospitalization he was gradually weaned off the ventilator, his renal and liver function tests improved and his tracheostomy was decannulated. He was clinically stable and hence was discharged (length of stay – 31 days) with advice to follow up with the nephrologist.
Discussion:
The majority of existing data on cerebral malaria comes from malaria-endemic countries. Without treatment, cerebral malaria is invariably fatal, but even with treatment, mortality rates as high as 30% have been reported in endemic regions. There can be significant long-term sequelae of cerebral malaria including motor function deficits, epilepsy, and death.
Our case illustrates a patient with cerebral malaria, radiographic evidence of severe brain injury and renal failure who had a near complete recovery three weeks after diagnosis.
Precautions
Travellers and their advisers should note the five principles – the ABCDE – of malaria protection:
A – Be Aware of the risk, the incubation period, the possibility of delayed onset, and the main symptoms.
B – Avoid being Bitten by mosquitoes, especially between dusk and dawn.
C – Take antimalarial drugs (Chemoprophylaxis) when appropriate, at regular intervals to prevent acute malaria attacks.
D – Immediately seek Diagnosis and treatment if a fever develops 1 week or more after entering an area where there is a malaria risk and up to 3 months (or, rarely, later) after departure from a risk area.
E – Avoid outdoor activities in Environments that are mosquito breeding places, such as swamps or marshy areas, especially in late evenings and at night.
Conclusion
The clinical presentation of patients infected with malaria varies depending on the Plasmodium species, level of parasitemia, and immune status of the host. Management of patients with severe malaria presents a broad array of clinical challenges given the complex pathophysiology of an infection that involves multiple organ systems. These challenges are increased in endemic areas where access to diagnostic and therapeutic tools may be limited.
Most severe malaria cases are attributable to P. falciparum (90%) but P.vivax and P.knowlesi can also cause severe complicated disease that is potentially life threatening. These P.vivax parasites can remain dormant in the liver for many months, causing a reappearance of symptoms months or even years later. The most important point in the management of malaria is early initiation of antimalarial therapy, treatment of any secondary infections and supportive care.
In 2018, a new country-driven response “High Burden to High Impact[1]” was launched by WHO to end malaria. It builds on the principle that no one should die from a disease that can be prevented and diagnosed, and that is entirely curable with available treatments.
Dr. Karishma Puthanpura
Department of Critical Care
Kauvery Hospital Chennai