ATI RN
Hematological System Questions
Question 1 of 5
The patient is a 6-year-old boy referred to a hematologist for thrombocytopenia. He has no bleeding history or family history of bleeding. His only other past medical history is mild high-frequency hearing loss. What gene is responsible for these findings?
Correct Answer: C
Rationale: Rationale for correct answer (C - MYH9): 1. MYH9 gene encodes for non-muscle myosin heavy chain IIA. 2. Mutations in MYH9 gene are associated with May-Hegglin anomaly, characterized by thrombocytopenia without bleeding tendency. 3. Additionally, MYH9-related disorders can present with sensorineural hearing loss. 4. Given the patient's thrombocytopenia and hearing loss, MYH9 gene is the most likely culprit. Summary of incorrect choices: A: NBEAL2 - Associated with gray platelet syndrome, not consistent with patient's presentation. B: GP-1Ba - Glycoprotein Ib-IX-V complex gene, not linked to the symptoms described. D: Deletions of long arm of chromosome 11 - Not specific to thrombocytopenia and hearing loss in this context.
Question 2 of 5
A 13-year-old girl presents with acute myeloid leukemia (AML) and a WBC count of 120,000/mm3. Cytogenetics reveals a normal karyotype, and fluorescence in situ hybridization (FISH) tests for inv(16), t(8;21), t(15;17); 11q23 abnormalities; monosomy 7; and 5q deletion are negative. Molecular testing is negative for mutations in FLT3, NPM1, and CEBPA. She is treated with 10 days of daunorubicin, AraC, and gemtuzumab for induction therapy. On day 30, she recovers counts, and a bone marrow aspiration shows 2.2% leukemic blasts by flow cytometry. She receives a second course of treatment with daunorubicin and AraC, and her marrow is now in morphologic remission and is MRD-negative by flow cytometry. She has no HLA-matched siblings, but an unrelated donor search reveals a large number of potential matches. Which course of treatment is most likely to result in the best outcome?
Correct Answer: C
Rationale: The correct answer is C: Give one more course of intensification chemotherapy and then perform a matched unrelated donor HSCT. In this scenario, the patient achieved morphologic remission and MRD-negative status after the second course of chemotherapy. Performing a matched unrelated donor HSCT can provide the best chance for long-term disease control and potential cure by replacing the patient's hematopoietic system with healthy donor cells, reducing the risk of relapse. This approach combines the benefits of achieving remission with chemotherapy and the potentially curative effects of allogeneic HSCT. The other choices are suboptimal: A may lead to excessive toxicity, B may not be as effective in preventing relapse, and D may not be as curative as HSCT in this high-risk case.
Question 3 of 5
A 5-year-old girl with a previously normal CBC now presents in your office with a hemoglobin of 8.5 g/dL, corrected reticulocyte count of 0.1%, and mean corpuscular volume of 80 fl. White cells and platelets are normal in number and morphology. Bilirubin, LDH, BUN, creatinine, and urinalysis are normal. Direct and indirect antiglobulin tests are negative. Workup for infection, including parvovirus, is negative. Occult blood in her stools is negative. Physical examination is unremarkable. She has had no restriction in her energy or activities and the family agrees she is 'fine.' What is the most appropriate next step in management?
Correct Answer: C
Rationale: The correct answer is C: Observe serial hemoglobin values closely. This is the most appropriate next step in management for a 5-year-old girl with a hemoglobin of 8.5 g/dL, normal white cells, and platelets. Given the absence of symptoms or signs of acute illness, a conservative approach of close observation is warranted. This allows monitoring for any trends in hemoglobin levels and the need for intervention. Administering erythropoietin (choice A) is not indicated as the patient is clinically stable and does not have evidence of erythropoietin deficiency. Initiating a red cell transfusion (choice B) is not necessary at this point since the patient is asymptomatic and stable. Prescribing oral iron supplement (choice D) is not appropriate as the MCV is normal, and there is no evidence of iron deficiency anemia.
Question 4 of 5
A 3-year-old boy with X-linked chronic granulomatosis disease is day +25 after haploidentical bone marrow transplant (father donor) using posttransplant cyclophosphamide as graft-versus-host disease (GVHD) prophylaxis. He engrafted on day +16 and was preparing for discharge when cytomegalovirus (CMV) was noted to be positive on PCR, and he developed a fever and mild rash. His counts have fallen to a WBC of 0.1 and he remains transfusion dependent. What diagnostic evaluations/treatments should you pursue?
Correct Answer: D
Rationale: Step-by-step rationale for why answer D is correct: 1. Send blood cultures: To rule out bacterial infection as a potential cause of fever and rash. 2. Start antibiotics: To cover for possible bacterial infection given the clinical presentation. 3. Treat CMV with foscarnet: As the patient is CMV positive on PCR and has developed symptoms, indicating active CMV infection. 4. Send rapid chimerism by STR: To assess for possible rejection post-transplant. Low or absent donor chimerism may indicate rejection. 5. If donor chimerism is low or absent: Consider the need for alternative donor for a second procedure to address rejection. Summary: - Choice A is incorrect because steroids for aGHVD are not indicated without confirming the diagnosis first. - Choice B is incorrect as the low blood counts are more suggestive of a different underlying cause rather than sepsis. - Choice C is incorrect as rapid FISH chimerism is not the standard method for assessing rejection
Question 5 of 5
An avid 16-year-old triathlete was in a bike accident and developed cellulitis, which was treated with Bactrim. While still on antibiotics, he moved with his family from Houston to Denver, and during the car trip he developed fever, pharyngitis, and malaise. Upon arriving in Denver he presented to the emergency department and was noted to have significant lymphocytosis with some atypical lymphocytes. What is the most likely cause of the white blood cell abnormalities?
Correct Answer: D
Rationale: The correct answer is D: Epstein-Barr virus infection. Firstly, the symptoms of fever, pharyngitis, malaise, and lymphocytosis with atypical lymphocytes are classic for infectious mononucleosis, which is caused by the Epstein-Barr virus. The patient's recent bike accident and antibiotic use are unrelated to the current symptoms. Altitude (choice B) does not cause lymphocytosis with atypical lymphocytes. GATA2 mutation (choice C) is a genetic disorder that can lead to immunodeficiency but is not the most likely cause in this scenario. Lastly, a drug reaction (choice A) is less likely given the patient's symptoms and history.