Morphological Features in Rare Qualitative Neutrophil Disorders: A Case Series

Background: Qualitative neutrophil disorders, such as Chronic Granulomatous Disease (CGD), are characterized by impaired intracellular killing of phagocytosed pathogens due to defects in the NADPH oxidase complex. Objective: This case series presents four rare qualitative neutrophil disorders, emphasizing the crucial role of morphological recognition in diagnosis. Methods: This retrospective observational case series includes four patients evaluated between July 2019 and November 2022 in the hematology section of the Department of Pathology, Kempegowda Institute of Medical Sciences, Bengaluru. The current primary diagnostic tool was peripheral blood smear examination of all the blood smears. We identified and analyzed four cases exhibiting classical morphological phenotypes. Results: The current analysis unveiled two separate sets of morphological traits for each disorder. In hereditary hypersegmentation, we noticed neutrophils with a number of nuclear lobes abnormally high, usually greater than 5. The Alder-Reilly anomaly was characterized by the presence of discrete, large azurophilic granules in both neutrophils and lymphocytes. These granules were particularly oversized. For the Chediak-Higashi abnormality, we encountered inclusions in neutrophils, which were large, greyish-blue granules. These granules were positive for peroxidase. Cytoplasmic vacuolation in granulocytes was the most remarkable feature of the Jordan anomaly. Such distinctive morphological observations were key findings in accurately defining each of these diseases, stressing the necessity of a detailed microscopic review in hematology diagnosis. Conclusion: Our findings suggested the necessity of meticulous microscopical review. Identification of these distinctive patterns is important in achieving an accurate diagnosis and understanding of these rare entities in hematology.