Retrospective study of association between Plasmodium falciparum malaria density and platelet count at Presbyterian Hospital, Agogo

Résumé

In malaria-endemic, resource-constrained settings, automated complete blood counts are widely accessible and could potentially supplement gold-standard microscopy. This study evaluated the relationship between Plasmodium falciparum parasite density and platelet count variations to determine the diagnostic screening and risk-stratification utility of acute thrombocytopenia. A retrospective observational study was conducted using laboratory data from 15,989 patient encounters at the Presbyterian Hospital in Agogo, Ghana, spanning September 2024 to September 2025. Continuous variables were evaluated using non-parametric frameworks (Mann-Whitney U, Kruskal-Wallis with post hoc Dunn’s test, and Spearman’s rank correlation). All statistical analyses were executed via R software (version 4.5.3). A binary logistic regression model and Receiver Operating Characteristic (ROC) curve analysis were constructed to determine the standalone predictive performance of platelet measurements. The overall slide positivity rate for P. falciparum was 10.6% (1,690/15,989), with transmission peaking during the major rainy season in May (14.53%) and June (16.07%). Median platelet counts were profoundly lower in malaria-positive individuals [143 (IQR: 87–206) ×10 3 /µL] than in uninfected subjects [223 (IQR: 175–279) ×10 3 /µL; p<0.001]. Platelet counts progressively declined with advancing age across the broad population (p < 0.001), but no significant biological divergence was identified between infected genders (p > 0.05). A statistically significant, moderate inverse correlation was confirmed between individual parasite density and platelet count (ρ= -0.34, 95% CI: -0.39 to -0.30, p < 0.001); however, platelet depletion plateaued at the highest burdens, showing no significant variance between high and severe parasitemia groups (p = 1.000). The predictive model mapped an intermediate Area Under the Curve (AUC = 0.771). At an optimized Youden’s threshold of 0.133, it demonstrated a balanced sensitivity of 63.6% and specificity of 79.9%. Acute thrombocytopenia is a consistent, pathophysiologically driven hallmark of P. falciparum infection that tracks peripheral parasite burden up to a point of physiological saturation. Due to distribution overlaps and structural class imbalances, standalone platelet metrics display insufficient diagnostic capacity to substitute for direct microscopy. Nonetheless, automated platelet counts offer substantial clinical utility as an objective, rapid screening tool to optimize patient triage and flag high-probability cases in rural diagnostics.

Citer ce document

Accès au document

Texte intégral en lecture en ligne, réservé aux abonnés SPHAERO et aux membres de l'institution. Se connecter

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0