A 14-year-old boy presents with progressive pancytopenia, dystrophic fingernails, and areas of lacy, reticular pigmentation on his neck and chest. A pathogenic variant in which gene is recognized as the most common cause of the most likely diagnosis?
A 2-year-old girl presents to her pediatrician with failure to thrive and a history of bulky, foul-smelling stools. Her complete blood count is notable for persistent neutropenia. In addition to bone marrow dysfunction, which of the following findings would most strongly support a diagnosis of Shwachman-Diamond syndrome?
A 15-year-old presents with advanced myelodysplastic syndrome (MDS) with monosomy 7. His history is notable for lymphedema and disseminated nontuberculous mycobacterial infections. He is found to have a germline GATA2 pathogenic variant. What is the only curative therapeutic option for the hematologic complications of his condition?
A 5-year-old girl is diagnosed with severe warm autoimmune hemolytic anemia (wAIHA) and presents with a hemoglobin of 4.5 g/dL and signs of cardiorespiratory distress. She is started on high-dose intravenous methylprednisolone. After 24 hours, her anemia worsens. What is the most critical next therapeutic intervention?
An 17-year-old male is evaluated for persistent headaches and is found to have a hemoglobin of 19.5 g/dL. His bone marrow biopsy shows hypercellularity with trilineage growth (panmyelosis). To confirm a diagnosis of polycythemia vera according to World Health Organization (WHO) criteria, which additional finding would satisfy the minor diagnostic criterion?
A 10-year-old girl with severe acquired aplastic anemia fails to show any hematologic improvement after a standard first-line course of immunosuppressive therapy with horse antithymocyte globulin and cyclosporine. Her family has been typed, and no matched sibling or matched unrelated donor is available. Which of the following is an appropriate and potentially curative next-line therapeutic consideration?
A 7-year-old boy presents with progressive pancytopenia, short stature, and a hypoplastic thumb. A chromosomal breakage study using diepoxybutane (DEB) on his peripheral blood lymphocytes shows no increased fragility. What is the most appropriate next diagnostic step?
A 6-month-old infant is admitted to the pediatric intensive care unit for sepsis and requires central venous access for administration of antibiotics and fluids. What is the single most important risk factor for the development of venous thromboembolism in this patient?
A 3-year-old girl presents with a 2-day history of widespread petechiae and bruising. Her platelet count is 8 × 10⁹/L, but she has no mucosal bleeding or other severe symptoms. The family is very anxious and requests treatment. Which of the following is the most appropriate initial management step according to current guidelines?
A 4-month-old infant presents at birth with severe bleeding, isolated thrombocytopenia, and absent megakaryocytes on bone marrow examination. Genetic testing reveals a missense pathogenic variant in the MPL gene. Based on this genotype, what is the most likely clinical course for this patient?
