Acute Respiratory and Renal Failure Following Delayed Recognition of T-cell Lymphoblastic Leukemia in a Previously...

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive pediatric hematologic malignancy that frequently presents with mediastinal involvement. Delayed recognition can result in rapid clinical deterioration due to airway compression, metabolic derangements, and treatment-related complications. We report the case of a previously healthy 12-year-old male who developed acute hypoxemic respiratory failure secondary to a large mediastinal mass initially treated as pneumonia, in whom imaging demonstrated a large anterior mediastinal mass with airway compression and a malignant right-sided pleural effusion with the diagnosis of T-ALL. The hospital course was complicated by severe tumor lysis syndrome resulting in oligo-anuric acute kidney injury, recurrent respiratory failure with acute lung injury, chemotherapy-induced pancytopenia, neutropenic enterocolitis, venous thrombosis, and persistent Candida albicans fungemia. Despite aggressive multidisciplinary management, the patient developed progressive multiorgan failure, and on the 46th day of hospitalization, he died from refractory fungal sepsis. This case underscores the importance of early chest imaging in pediatric patients with persistent respiratory symptoms unresponsive to antibiotics. It highlights the complexity of managing overlapping oncologic and critical care emergencies in children with T-ALL.