A rare case of erythrophagocytosis by neutrophils on the peripheral blood smear

An AI-based imaging flow cytometry approach to study erythrophagocytosis

Erythrophagocytosis is a process consisting of recognition, engulfment and digestion by phagocytes of antibody-coated or damaged erythrocytes. Understanding the dynamics that are behind erythrophagocytosis is fundamental to comprehend this cellular process under specific circumstances. Several techniques have been used to study phagocytosis. Among these, an interesting approach is the use of Imaging Flow Cytometry (IFC) to distinguish internalization and binding of cells or particles. However, this method requires laborious analysis. Here, we introduce a novel approach to analyze the phagocytosis process by combining Artificial Intelligence (AI) with IFC. Our study demonstrates that this approach is highly suitable to study erythrophagocytosis, categorizing internalized, bound and non-bound erythrocytes. Validation experiments showed that our pipeline performs with high accuracy and reproducibility.

Neutrophil-mediated erythrophagocytosis following Russell's viper (Daboia russelii) bite

Snakebite envenomation is regarded as a high-priority neglected tropical disease by the World Health Organisation, as it results in significant loss of lives and permanent disabilities. Russell's viper is one of the snakes that causes morbidities, mortalities and disabilities in India. The clinical presentation of Russell's viper envenomation is characterised by local envenoming effects, tissue damage, venom-induced coagulopathy, neurotoxicity, and kidney injury. However, venom composition and its mechanisms of toxicity are highly variable even within snakes of the same species including Russell's viper. This variation in venom composition results in a broad range of clinical complications. Here we present a previously undocumented case of neutrophil-mediated erythrophagocytosis in a healthy 28-year-old female following Russell's viper bite. Systemic envenomation effects and bleeding abnormalities in this patient were corrected by the administration of polyvalent antivenom. Two days later, the patient developed progressive swelling and ecchymosis in the bitten limb. Observed abnormal limits within blood testing were followed up by a peripheral blood smear where it was found that 30% of neutrophils had phagocytosed erythrocytes as they were found within the cytoplasm. The patient underwent a fasciotomy for compartmental syndrome and received packed red cells and a course of corticosteroids. Following this treatment, the patient made a full recovery. This case report outlines a previously undocumented pathological event induced by Russell's viper envenomation, guiding diagnosis and treatment. Clinicians' knowledge of the mechanisms of toxicity of Russell's viper envenomation and its clinical manifestations are essential for improving the treatment of snakebites to achieve positive outcomes.

Neutrophilic erythrophagocytosis in myelodysplastic syndrome and cold agglutinin disease co-occurrence

In this article, we report the rare phenomenon of erythrophagocytosis by neutrophils in peripheral blood smear of a 56-year-old male patient with concurrent myelodysplastic syndrome and cold agglutinin disease.