Fine-Needle Aspiration as a Key Diagnostic Tool in Pediatric Rosai-Dorfman Disease: A Case Report of a 12-Year-Old Male

Charles Malisaba Posite,1– 3 Mahad Said Mohamed,1 Eluzai Ndiwelubula,4 Samuel Tumwesigire,1,5 Suleman Essa Ahmed,1 Henry Wabinga,1 Raymond Atwine,1,5 Biruk Legesse Tadesse1 1Department of Pathology, Kampala International University Western Campus, Ishaka-Bushenyi, Uganda; 2Department of Pathology, Catholic University of Graben, Butembo, Democratic Republic of the Congo; 3Department of Planetary Health and Climate Resilience Lab, EarthRoost+, Beni, Democratic Republic of the Congo; 4Department of Radiology, Kampala International University, Ishaka, Uganda; 5Department of Pathology, Mbarara University of Science and Technology, Mbarara, UgandaCorrespondence: Charles Malisaba Posite, Department of Pathology, Kampala International University Western Campus, Ishaka-Bushenyi, Uganda, Email charles.malisaba@studwc.kiu.ac.ugBackground: Rosai-Dorfman Disease (RDD) is a rare, benign, non-Langerhans cell histiocytosis characterized primarily by massive, painless cervical lymphadenopathy. Its low prevalence (~ 1:200,000) and clinical similarity to endemic conditions like tuberculosis and lymphoma make the diagnosis challenging, particularly in resource-limited settings. Definitive diagnosis hinges on identifying S100-positive histiocytes exhibiting the pathognomonic feature of emperipolesis.Case Presentation: A previously healthy 12-year-old male from Uganda presented with a one-month history of progressive, asymptomatic, bilateral cervical lymphadenopathy. Systemic symptoms were absent. A provisional diagnosis of RDD was established rapidly via Fine Needle Aspiration Cytology (FNAC). Cytological smears showed abundant histiocytes demonstrating clear emperipolesis, confirming the classic cytological diagnosis. Despite the recommendation for a confirmatory excisional biopsy and further subtyping, the patient was lost to follow-up.Conclusion: This case demonstrates that high-quality FNAC can reliably establish the diagnosis of RDD in environments where advanced diagnostic tools are scarce, but also underscores the critical need to strengthen patient follow-up systems to ensure complete evaluation and long-term monitoring of rare histiocytic disorders.Keywords: Rosai-Dorfman Disease, Fine Needle Aspiration Cytology, Emperipolesis, Cervical Lymphadenopathy, Uganda