Autoimmune lymphoproliferative syndrome (ALPS) is a disorder of lymphocyte apoptosis characterized by nonmalignant lymphadenopathy, splenomegaly, immune dysregulation, and autoimmune cytopenias. Langerhans cell histiocytosis (LCH) is a neoplasm of myeloid precursor cells, primarily presenting as bone, soft tissue, lung, skin, and pituitary lesions. The association between the two diagnoses is uncharacterized. Here we describe a patient presenting with fever of unknown origin, cytopenias, and failure to thrive. She was diagnosed with ALPS, then subsequently LCH, within three months. This case highlights the diagnostic and management challenges associated with these two rare diagnoses.

Diamond-Blackfan Anemia (DBA) is a rare congenital bone marrow failure syndrome typically diagnosed during infancy and is characterized by macrocytic anemia, congenital malformations, and predisposition to cancer. There were 32 patients treated for DBA at a single tertiary care referral center from 2000-2022. A retrospective chart review characterized patient presentation at diagnosis, the clinical course of each patient, and the various treatment strategies with correlation to patient outcome. Our study emphasizes the importance of screening for DBA in patients who present with macrocytic anemia regardless of age at presentation as a substantial proportion of patients presented after infancy.