Paediatric Castleman Disease: Diagnostic Challenges and Lessons from Two Rare Cases

Abstract

Castleman disease (CD) is a rare and heterogeneous lymphoproliferative disorder that affects both children and adults, typically presenting in young to middle-aged individuals. It is classified clinically as unicentric Castleman disease (UCD), which typically affects a single lymph node region and is often of the hyaline vascular subtype, or multicentric Castleman disease (MCD), which involves multiple lymph node stations and systemic inflammation. MCD includes HHV‑8–associated MCD and idiopathic MCD (iMCD), each with distinct diagnostic and therapeutic profiles. CD can mimic various malignant, infectious, and autoimmune diseases, leading to frequent diagnostic challenges. Although paediatric cases are uncommon, they often exhibit overlapping clinical and histological features, necessitating a high index of suspicion for accurate diagnosis and management. Two rare paediatric cases of Castleman disease are reported, involving a 7-year-old and a 9-year-old male, each presenting with atypical symptoms and complex clinical profiles. The first case presented with progressive respiratory distress, cachexia, generalized lymphadenopathy, and a mediastinal mass initially suspected to be lymphoma. Although histopathology demonstrated hyaline vascular Castleman disease—a subtype typically seen in unicentric disease—the extent of lymphadenopathy and systemic compromise indicated a multicentric clinical behavior. Histopathology revealed hyaline vascular Castleman disease. The second case presented with prolonged fever, cough, pleural effusion, hepatosplenomegaly, nephropathy, and cardiac dysfunction. These widespread systemic abnormalities are more suggestive of multicentric Castleman disease (MCD), despite the hyaline vascular histologic findings. Extensive investigations excluded infectious and malignant causes, and lymph node biopsy confirmed hyaline vascular Castleman disease. Both cases required multidisciplinary evaluation and were subsequently referred for specialized tertiary management. Castleman disease, though rare in children, should be considered in cases of persistent lymphadenopathy and systemic illness unresponsive to conventional therapy. Early biopsy and histopathological confirmation remain essential for diagnosis, while timely referral and multidisciplinary management optimize outcomes. Increased awareness, improved diagnostic access, and expanded availability of immunomodulatory therapy are critical to improving prognosis in paediatric Castleman disease.