The selective outpatient treatment of adults with imported falciparum malaria: a prospective cohort study

Background: Current UK malaria treatment guidelines recommend admission for all patients diagnosed with falciparum malaria. However, evidence suggests that certain patients are at lower risk of severe malaria and death and may be managed as outpatients. Aim: To prospectively assess the risk of post-treatment severe falciparum malaria in selected cases managed as outpatients. The readmission rate and treatment tolerability were assessed as secondary outcomes. Design: Prospective cohort study. Methods: Adults (>15 years old) diagnosed with falciparum malaria between May 2008 and July 2012 were selected for outpatient treatment using locally defined clinical and laboratory indicators based on known risk factors for severity and death. Treatment outcomes were assessed in clinic or by telephone 4–6 weeks after treatment. Results: 269 adults were diagnosed with falciparum malaria on blood film between May 2008 and July 2012. Of 255 eligible participants, 106 patients were offered ambulatory treatment, of which 95 completed the study. The severe malaria rate was 0% (95% confidence interval (CI) 0–3.8%) and the readmission rate was 5.3% (95% CI 1.7–11.9) in the outpatient group. In addition, 10.6% (95% CI 5.2–18.7%) of outpatients reported drug-related side effects. Conclusions: The outpatient treatment of selected cases of falciparum malaria is effective in our high volume UK setting. We recommend adopting a similar approach to managing this infection in other non-endemic settings where immediate access to specialist advice is available.