ATI RN
Hematological System Questions
Question 1 of 5
You are asked to evaluate a 2-day-old boy in the newborn nursery with petechiae who has a platelet count of 8,000/mcL. On further questioning, you learn that he had a maternal uncle who died of intracerebral hemorrhage as a toddler. There is no eczema on physical examination. Review of the smear shows anisocytosis; poikilocytosis; normal white blood cell morphology; and small, infrequent platelets. The neonatologists have sent human platelet antigen (HPA)-1a testing from both parents, which is pending. Which of the following is the most likely diagnosis?
Correct Answer: C
Rationale: The most likely diagnosis is Wiskott-Aldrich syndrome (C). This is supported by the presence of petechiae, low platelet count, family history of bleeding, anisocytosis, poikilocytosis, small platelets, and normal white blood cell morphology. Wiskott-Aldrich syndrome is an X-linked disorder characterized by thrombocytopenia, eczema, and recurrent infections. The absence of eczema in this case could be due to the young age of the patient. The other choices can be ruled out based on the clinical presentation and laboratory findings. Congenital infection (A) typically presents with other systemic symptoms. Neonatal alloimmune thrombocytopenia (B) usually presents with maternal history of previous pregnancies with affected infants. May-Hegglin anomaly (D) would typically present with giant platelets and Döhle-like inclusion bodies in neutrophils, which are not seen in this case.
Question 2 of 5
A 7-year-old Hispanic male is referred to the hematology consult service by his pediatrician because of concern for hemoglobinopathy. In his records, you find a hemoglobin electrophoresis performed last year which shows hemoglobin A 78% and hemoglobin F 22%. His complete blood count is normal, and he has normal growth and development. Which of the following is true for this patient?
Correct Answer: D
Rationale: The correct answer is D because hereditary persistence of fetal hemoglobin (HPFH) is a condition where there is a lifelong elevation of fetal hemoglobin (HbF) levels. In HPFH, the distribution of HbF is pancellular, meaning it is present in all red blood cells. This patient's hemoglobin electrophoresis shows a significant amount of HbF (22%), which is consistent with HPFH. Choice A is incorrect because a significant elevation of HbF in a 7-year-old is not considered normal and warrants further investigation. Choice B is incorrect because delta-beta thalassemia typically presents with a different hemoglobin pattern on electrophoresis. Choice C is incorrect because delta-beta thalassemia can indeed cause microcytosis due to ineffective erythropoiesis.
Question 3 of 5
A newborn male has severe bleeding after circumcision, resulting in the need for a blood transfusion. You are called to consult on this child, and you diagnose him with severe hemophilia A. Upon taking a family history, you note that no other family members have hemophilia, other bleeding disorders, or a bleeding diathesis. Which of the following is the most likely outcome of genotyping the Factor VIII gene?
Correct Answer: C
Rationale: The correct answer is C: An inversion mutation in the F8 gene will be identified. In hemophilia A, around 50% of cases are due to large intragenic inversions involving the Factor VIII gene. In this scenario, since there is no family history of hemophilia or other bleeding disorders, the most likely genetic cause is an inversion mutation in the F8 gene. This type of mutation is not dependent on a family history and can occur spontaneously. Missense mutations (choice B) and nonsense mutations (choice D) are less common in hemophilia A and are not the typical genetic abnormalities associated with this condition. Choice A is incorrect because the absence of a family history does not rule out the possibility of a genetic mutation.
Question 4 of 5
A healthy 17-year-old African American male presents with a thrombosis of the right upper extremity. His past medical history is remarkable only for sickle cell trait. The history is negative for recent risk factors for thrombosis (illness, surgery, immobility). He is the pitcher for his high school baseball team. Imaging confirms anatomical compression/narrowing of the right subclavian vein. Which of the following interventions is most likely to decrease this patient's long-term risk of recurrent thrombosis?
Correct Answer: D
Rationale: The correct answer is D: Resection of right first rib. The patient likely has thoracic outlet syndrome (TOS), which is causing compression of the subclavian vein leading to thrombosis. Resection of the right first rib is the definitive treatment for TOS, as it relieves the compression on the vein. This intervention addresses the root cause of the thrombosis, reducing the risk of recurrence. A: Systemic thrombolysis is not indicated in this case as it carries an increased risk of bleeding and may not address the underlying cause of the thrombosis. B: Catheter-directed thrombolysis is not the primary treatment for TOS and may not prevent recurrence. C: Anticoagulation with LMWH does not address the underlying compression of the vein and is not the primary treatment for TOS.
Question 5 of 5
Iron-refractory iron deficiency anemia (IRIDA) is a rare inherited condition characterized by congenital iron deficiency anemia, poor response to oral iron, and partial but incomplete response to intravenous iron therapy. Which is the genetic mutation associated with IRIDA?
Correct Answer: C
Rationale: The correct answer is C: TMPRSS6. Mutations in TMPRSS6 gene are associated with IRIDA. TMPRSS6 encodes matriptase-2, a key negative regulator of hepcidin, a hormone that controls iron absorption. Mutations in TMPRSS6 lead to impaired hepcidin regulation, resulting in reduced iron absorption and subsequent iron deficiency anemia. Choice A: TFR2 mutations are associated with hereditary hemochromatosis, not IRIDA. Choice B: H63D mutation in HFE gene is also associated with hereditary hemochromatosis, not IRIDA. Choice D: EPOR mutations are associated with congenital erythrocytosis, not IRIDA.