Malaria in children: Case

This child has imported Plasmodium vivax malaria, the classic relapsing species seen in children returning from Papua New Guinea and South Asia. Her fever, pallor, and splenomegale, alongside a low parasitaemia and an alert conscious level with no severity features, place her in the uncomplicated category, which means oral therapy rather than intravenous artesunate. The distinctive issue with vivax is the dormant liver hypnozoite, which causes relapse unless a radical cure is given. [1]

Clinical findings

The key findings are the travel history to Papua New Guinea six weeks earlier, the splenomegaly that points to a parasitic process, and the low parasitaemia without severity features. She is alert and haemodynamically stable, has no respiratory distress, and her blood film shows vivax rather than falciparum. The differential includes the other travel-related fevers, but the blood film is definitive and the species identification changes both the acute treatment and the need for radical cure. [1]

Because she has no World Health Organization severity features, she does not need intravenous artesunate or intensive care, but she does need a full blood count to define her anaemia and a glucose-6-phosphate dehydrogenase assay before any primaquine is given. A child returning from Southeast Asia with a film that looks like malariae but with a higher density should instead raise the question of knowlesi, which is managed as falciparum with an artemisinin-combination therapy. [3]

Management

Treat the blood stage of her vivax malaria with an artemisinin-combination therapy for three days, which is appropriate even in regions where chloroquine resistance is emerging and which clears the circulating parasites. Artemether-lumefantrine is the most widely used regimen and is well tolerated in children, and she is reviewed on day three with a repeat smear to confirm a falling parasitaemia. [1]

Add a radical cure with primaquine to eradicate the dormant liver hypnozoites and prevent the relapses that otherwise recur weeks to months after the initial illness. Primaquine is given only after confirming a normal glucose-6-phosphate dehydrogenase status, because deficient children risk severe haemolysis, and tafenoquine offers a single-dose alternative in suitable patients. Counsel the family that vivax can relapse despite correct treatment, and provide a clear safety-net for any further febrile episode. [1]

Complications and follow-up

Although uncomplicated vivax usually resolves well, the dominant complication is relapse from persistent hypnozoites, which is why the radical cure is essential rather than optional. Splenic enlargement and, rarely, splenic rupture are recognised with vivax, so families are advised about abdominal trauma and warned to re-present with abdominal pain. Anaemia may take weeks to recover, and folate supplementation supports marrow recovery if the haemoglobin is slow to rise. [1]

If her clinical course had warranted intravenous artesunate, she would additionally need follow-up blood counts over the four weeks after discharge because post-artesunate delayed haemolysis can occur in non-immune travellers. In this uncomplicated case the priority is adherence to the artemisinin-combination therapy and the primaquine radical cure, surveillance for relapse, and a clear plan for the family to re-present with any further fever within the next few months. [2]