An 8-year-old boy, with a history of relapsed acute myeloid leukemia (AML) after an UCT, is admitted to the hospital to begin preparation for a second HCT, using a second UCB graft that will be infused in 7 days. On the third day of his myeloablative preparative chemotherapy, 4 days prior to infusion of his second transplant, he develops a temperature of 39.8°C. On examination, he is hypotensive (blood pressure is 64/32 mmHg) and tachycardic at 150 beats/min. His lungs are clear to auscultation. Blood cultures are obtained from his central line, and he is started on broad-spectrum empiric antibacterial antibiotics. He receives multiple fluid boluses and his hemodynamic status improves. Question: What is the likely underlying etiology of his hemodynamic change? Answer: Gram-positive infection of his central venous catheter.
A 9-year-old boy with a history of cerebral adrenoleukodystrophy (c-ALD) underwent an UCT approximately 18 months ago. His HCT course was complicated by autoimmune cytopenias for which he received multiple therapies over the last year including rituximab, IVIG, mycophenolate mofetil (MMF), daratumumab, and steroids. He presented to the ED with increased work of breathing and oxygen saturation of 86% while breathing room air. On auscultation of his lungs, he had poor aeration bilaterally and copious coarse breath sounds. His Covid-19 testing was negative. He was transferred to the PICU for respiratory support. At the time of admission, he was not on any prophylactic antimicrobial agents. Question: What is the likely underlying etiology of his sudden respiratory distress? Answer:\nPneumocystis pneumonia.