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: The correct answer is C: MYH9, as mutations in the MYH9 gene are associated with May-Hegglin anomaly, which presents with thrombocytopenia and hearing loss. NBEAL2 (choice A) is linked to gray platelet syndrome, not hearing loss. GP-1Ba (choice B) is a platelet glycoprotein, not associated with hearing loss. Deletions of the long arm of chromosome 11 (choice D) are related to Jacobsen syndrome, which presents with thrombocytopenia but not hearing loss. Thus, based on the presented clinical findings, MYH9 is the most likely gene responsible.
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. Performing a matched unrelated donor HSCT after one more course of intensification chemotherapy is the best course of treatment for the 13-year-old girl with AML. This is because although she achieved morphologic remission and MRD negativity after the second course of chemotherapy, HSCT provides the best chance for long-term disease control and potential cure in high-risk AML cases, especially in the absence of HLA-matched siblings. Autologous HSCT (choice B) is not preferred due to the high risk of relapse in AML. Giving two more courses of chemotherapy (choice A) may not provide additional benefit and can increase toxicity. Lastly, giving one more course of chemotherapy followed by maintenance chemotherapy (choice D) is not as effective as proceeding with HSCT to eliminate any residual disease and prevent relapse.
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. The 5-year-old girl has a low hemoglobin level with normal white cells and platelets, suggestive of a chronic process. Given the normal physical exam, lack of symptoms, and negative workup for infection or hemolysis, it is reasonable to observe serial hemoglobin values closely. This approach allows monitoring for any trends or significant drops in hemoglobin levels, which may prompt further investigation or intervention. Administering erythropoietin (choice A) is not indicated as there is no evidence of bone marrow failure. Initiating a red cell transfusion (choice B) is not necessary as the patient is asymptomatic with no signs of acute blood loss. Prescribing oral iron supplement (choice D) is not appropriate as the patient has normal iron studies and mean corpuscular volume, indicating a non-iron deficiency etiology.
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 correct answer D: 1. Send blood cultures to rule out bacterial infection due to fever and low WBC. 2. Start antibiotics to cover for potential bacterial infection. 3. Treat CMV with foscarnet due to positive PCR and clinical symptoms. 4. Send rapid chimerism by STR to assess for possible rejection. 5. If donor chimerism is low or absent, consider alternative donor for a second procedure. Summary of incorrect choices: A: Skin biopsy and steroids for aGHVD are not appropriate without confirming the diagnosis. B: Low blood counts are more likely due to CMV and not sepsis in this context. C: Testing for rejection is premature without addressing the immediate issues of infection and CMV.
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. The presentation of fever, pharyngitis, malaise, lymphocytosis, and atypical lymphocytes is classic for infectious mononucleosis caused by Epstein-Barr virus. The patient's symptoms started after the bike accident and while on antibiotics, suggesting a new infectious etiology. This viral infection commonly causes lymphocytosis with atypical lymphocytes. Choice A (Drug reaction) is less likely as the symptoms started after the antibiotics were initiated. Choice B (Altitude higher than 5,000 ft above sea level) is unlikely to cause these specific white blood cell abnormalities. Choice C (GATA2 mutation) is less likely as there are no indications in the scenario to suggest a genetic disorder.