Complicated malaria in children and adults from three settings of the Colombian Pacific Coast: A prospective study

Abstract

Background: Complicated malaria remains an important public health problem, particularly in endemic settings where access to health services is limited and consequently malaria fatal outcomes occur. Few publications describing the clinical course and outcomes of complicated malaria in Latin America are found in the literature. This prospective study approached the clinical and laboratory characteristics of hospitalized patients with complicated malaria in different endemic areas of the Colombian Pacific Coast with the aim to provide epidemiological knowledge and guide to further reducing malaria severity and mortality.

Methods and findings: A prospective, descriptive hospital-based study was conducted in 323 complicated malaria patients (median age 20 years) enrolled in Quibdó, Tumaco and Cali between 2014 and 2016. Clinical evaluation was performed and laboratory parameters were assessed during hospitalization. Plasmodium falciparum was the most common parasite species (70%), followed by P. vivax (28%), and mixed malaria (Pf/Pv; 1.9%). Overall, predominant laboratory complications were severe thrombocytopenia (43%), hepatic dysfunction (40%), and severe anaemia (34%). Severe thrombocytopenia was more common in adults (52%) regardless of parasite species. Severe anaemia was the most frequent complication in children ≤10 years (72%) and was most commonly related to P. vivax infection (p < 0.001); whereas liver dysfunction was more frequent in older patients (54%) with P. falciparum (p < 0.001). Two deaths due to P. vivax and P. falciparum each were registered. Treatment provision before recruitment hindered qPCR confirmation of parasite species in some cases.

Conclusions: The study identified a high prevalence of complicated malaria in the Pacific Coast, together with more frequent severe anaemia in children infected by P. vivax and hepatic dysfunction in adults with P. falciparum. Results indicated the need for earlier diagnosis and treatment to prevent complications development as well as more effective attention at hospital level, in order to rapidly identify and appropriately treat these severe clinical conditions. The study describes epidemiological profiles of the study region and identified the most common complications on which clinicians must focus on to prevent mortality.

Fig 1. Distribution of complicated malaria cases in the study areas.

For each of the three study sites, the total number of complicated malaria cases is shown on the map, as well as a pie chart with the proportion of Plasmodium species per site. Plasmodium vivax cases were more frequent in Cali (61%), whereas P. falciparum infections were more common in Quibdó (56%) and Tumaco (99%).

Fig 2. Prevalence and parasite species distribution according to age.

Percentage of individuals infected with either P. falciparum or P. vivax parasites stratified by age group. Statistical differences between P. falciparum and P. vivax infections were calculated using the Chi-square test. *p value < 0.05, **p value < 0.01, *** p value < 0.001.

Fig 3. Frequency of clinical manifestations in P. falciparum and P. vivax infections.

Percentages of malaria patients that reported every symptom (A) or presented with the listed clinical findings (B) are shown. All patients reported more than one symptom or had more than one sign. Statistical differences between species were calculated using the Chi-square test. *p value < 0.05, **p value < 0.01, *** p value < 0.001.

Fig 4. Frequency of complications by age group.

Percentage of malaria patients that presented each of the indicated WHO/MoH complication laboratory criterion are shown for children ≤10 years of age (A) and individuals >10 years (B).

Fig 5. Frequency of laboratory complications in P. falciparum and P. vivax cases.

Percentage of malaria patients that presented each of the indicated WHO/MoH complicated laboratory criterion are shown for each Plasmodium species.