Abstract / Summary
Purpose: To examine whether associations among routine admission laboratory measurements in imported Plasmodium falciparum malaria persist after accounting for other measured variables, including C-reactive protein (CRP).
Methods: This retrospective single-centre study included all adults recorded in a departmental malaria database as hospitalised with microscopically confirmed P. falciparum monoinfection between 2010 and 2025. A rank-based precision matrix yielded 28 partial correlations among seven laboratory measurements and age, each adjusted for the other six variables. Bonferroni correction was applied to the primary matrix. CRP-adjusted subset analyses and Firth logistic models were exploratory.
Results: The primary cohort comprised 48 patients. Three partial correlations survived correction: alanine aminotransferase with aspartate aminotransferase (partial rho +0.88), haemoglobin with red blood cell count (partial rho +0.82) and CRP with platelet count (partial rho - 0.56). Platelet associations with procalcitonin and urea were attenuated after CRP adjustment (n = 39 and 35). In univariate Firth models, CRP was associated with concurrent severe thrombocytopenia (15 events; odds ratio 3.57 per standard deviation, 95% CI 1.70 to 9.15), whereas evidence for an association with parasitaemia was inconclusive.
Conclusion: Routine laboratory abnormalities in falciparum malaria should be interpreted in their inflammatory and clinical context; their co-occurrence does not establish a direct link between organ injuries. Partial correlation analysis can explore this distinction but cannot determine whether an association is caused by inflammation or is organ-specific. These findings support contextual interpretation, not new diagnostic thresholds or treatment recommendations, and require prospective external validation.