Role of Morphology in the Diagnosis of an Unsuspected Case of Chediak-Higashi Syndrome: A Case Report.

Chediak-Higashi syndrome (CHS) is a rare multisystem genetic disorder of childhood, caused by a defect in vesicular trafficking, which is an essential process for intracellular transport. This defect results in the formation of giant cytoplasmic granules in various cell types, including white blood cells, melanosomes, and Schwann cells. The presence of giant lysosomal granules in neutrophils and their precursors is a distinct and diagnostic feature of CHS, differentiating it from other childhood immunodeficiency disorders, such as Griscelli syndrome and Hermansky-Pudlak syndrome, which share common characteristics like albinism and increased susceptibility to fatal hemophagocytic lymphohistiocytosis.

Cytological Diagnosis of Rosai-Dorfman Disease: A Study of Twelve Cases with Emphasis on Diagnostic Challenges.

Context: Rosai-Dorfman disease, also known as Sinus histiocytosis with massive lymphadenopathy, is a benign proliferative disorder of histiocytes. It typically affects lymph nodes; however, extranodal disease is being increasingly reported. The latter entity poses exceptional diagnostic challenge clinico-radiologically by forming mass lesions.