Haematological abnormalities as diagnostic indicators of malaria in returning travellers: a retrospective study at Mohamed V Military Instruction Hospital

Introduction. Malaria remains a significant global health concern, particularly in travellers returning from endemic regions. Haematological abnormalities are often associated with malaria and can serve as diagnostic indicators, especially when clinical symptoms are nonspecific. Objective. This study aims to identify the most relevant haematological parameters for diagnosing malaria in travellers returning from endemic areas, who sought care at the Mohamed V Military Instruction Hospital in Rabat. Methods. We conducted a retrospective comparative study involving 829 patients who returned from malaria-endemic regions between January 2017 and December 2023. Data collected included demographic information, parasitological test results and comprehensive haematological profiles. Statistical analysis was performed to determine the sensitivity and specificity of various haematological parameters in diagnosing malaria. Results. Thrombocytopenia, lymphocytopenia and anaemia were the most significant haematological abnormalities associated with malaria. Thrombocytopenia, defined as a platelet count below 150×10³ µl −1 , demonstrated a sensitivity of 75.91% and a specificity of 84.11%. Lymphocytopenia, with a threshold of less than 1.5×10³ µl −1 , showed a sensitivity of 69.47% and a specificity of 78.39%. Anaemia, defined by haemoglobin levels below 13 g dl −1 in men and 12 g dl −1 in women, also significantly correlated with malaria diagnosis. Discussion. This study highlights the significance of haematological abnormalities as key diagnostic markers for imported malaria cases. By analysing retrospective data, we observed that these abnormalities, especially thrombocytopenia and anaemia, are common amongst returning travellers with confirmed malaria. These findings suggest that clinicians can use such markers as a valuable tool for early malaria diagnosis, potentially improving patient outcomes. Additionally, the study reinforces the need for heightened awareness amongst healthcare providers in non-endemic regions regarding the presentation of malaria in travellers. Conclusion. Haematological parameters such as thrombocytopenia, lymphocytopenia and anaemia are valuable diagnostic tools for malaria in returning travellers. These findings suggest that these parameters should be integrated into diagnostic protocols to improve the accuracy and timeliness of malaria diagnosis, particularly in clinical settings with limited access to advanced diagnostic tools.