Bicytopénie et hémolyse : stratégies diagnostiques et orientation en urgence

The association of anaemia and thrombocytopenia is common. However, when haemolysis is also present, different diagnoses, of varying severity, should be considered, in particular thrombotic microangiopathy (TMA). The challenge is to establish a rapid diagnosis without delaying treatment. The main aim of this study was to describe the potential differential diagnoses, to establish predictive factors of TMA and to propose a diagnostic score. Materials and Methods: Patients with anaemia <12 g/dL, thrombocytopenia <150G/L and haptoglobin <0.3g/L admitted to the departments of Internal Medicine, General Medicine, Geriatrics, Adult Emergency and Medical Intensive Care of Rouen University Hospital between the 15th of October 2009 and the 31st of December 2020 were retrospectively included. Patients with cirrhosis were excluded. Demographic, clinical and biological data were collected on days 1, 2 and 3. A TMA diagnostic score was developed based on significant data from a multivariate analysis. Results: A total of 108 patients were included in the study. The main diagnoses were TMA (37%) and vitamin deficiency (36.1%). Nearly 60% of patients with a diagnosis of TMA presented an incomplete biological profile at baseline. Systolic blood pressure (OR 1.081; 95% CI [1.015-1.152]), platelet level (OR 0.935; 95% CI [0.891-0.981]), LDH (OR 0.996 ; 95% CI [0.993-0.999]), reticulocytes (OR 1.017; 95% CI [1.003-1.032]) and creatinine (OR 1.016; 95% CI [1.003-1.029]) were significantly associated with TMA in multivariate analysis. The diagnostic score had a sensitivity of 88.9%, a specificity of 93.6%, a positive predictive value of 88.9% and a negative predictive value of 93.6%. Conclusion: In a context of haemolytic bicytopenia, the diagnoses to be considered are TMA and vitamin deficiency-related causes. Initial biological data can be misleading. Our score could be a useful tool in the diagnosis of TMA in the case of an unusual biological profile. ; L’association d’une anémie et d’une thrombopénie est fréquente. La ...