Nokea
Which of the following best characterizes the function of ferroportin in iron metabolism?
- A. A form of storage iron in intestinal mucosal cells
- B. A transport protein in the plasma
- C. A receptor protein on the surface of erythroid progenitors
- D. Transmembrane iron exporter
Correct Answer: D
Rationale: Ferroportin is a transmembrane iron exporter responsible for releasing iron from cells into the bloodstream. It is crucial in regulating systemic iron levels. Choice A is incorrect as storage iron is typically stored as ferritin. Choice B is incorrect as ferroportin is not found in the plasma but on cell membranes. Choice C is incorrect as erythroid progenitors do not directly interact with ferroportin. Therefore, the correct answer is D as it accurately describes the function of ferroportin in iron metabolism.
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A 9-month-old boy has been referred to you for the evaluation of an enlarged abdomen. Imaging studies show a large liver mass (PRETEXT III). Alfa-fetoprotein is 98 ng/mL, and a CT scan of the lungs show bilateral lung metastases. A needle biopsy is performed, and you are planning to review the specimen with the pathologist. Which of the following diagnoses are you suspecting?
- A. Pure fetal histology hepatoblastoma
- B. Embryonal sarcoma of the liver
- C. Fibrolamellar hepatocellular carcinoma
- D. Small cell undifferentiated hepatoblastoma
Correct Answer: D
Rationale: The correct answer is D: Small cell undifferentiated hepatoblastoma. In this case, the key features to consider are the patient's age (9 months old), large liver mass with lung metastases, and elevated alpha-fetoprotein level. Small cell undifferentiated hepatoblastoma is commonly seen in infants, presents as a large liver mass, and frequently metastasizes to the lungs. The alpha-fetoprotein level in this case is also elevated, which is typical for hepatoblastoma. Pure fetal histology hepatoblastoma (A) is less common in older infants, and the presence of lung metastases is not typical. Embryonal sarcoma (B) typically presents as a solitary mass without metastases. Fibrolamellar hepatocellular carcinoma (C) is rare in infants and does not typically present with elevated alpha-fetoprotein levels. Thus, based on the clinical presentation and imaging findings, small cell undifferentiated hepatob
A 7-year-old boy presents with recent onset of vomiting and lethargy. Blood smear shows increased neutrophils with a left shift and 8% abnormal cells. Bone marrow contains 60% of the same cells. Flow cytometry shows that the cells are TdT–, CD10+, CD19+, CD20+, sIg+. What is the most likely diagnosis?
- A. Burkitt leukemia/lymphoma
- B. B-cell acute lymphoblastic leukemia (ALL)
- C. T-cell ALL
- D. Hematogones
Correct Answer: A
Rationale: The correct answer is A: Burkitt leukemia/lymphoma. The key features in the case are increased neutrophils with a left shift, presence of abnormal cells in blood and bone marrow, and flow cytometry showing TdT–, CD10+, CD19+, CD20+, sIg+. These findings are consistent with Burkitt leukemia/lymphoma, a highly aggressive B-cell neoplasm. The presence of CD10, CD19, and CD20, along with sIg positivity, points towards a B-cell origin. Additionally, the characteristic translocation t(8;14) involving c-Myc oncogene is commonly seen in Burkitt lymphoma. The absence of TdT expression rules out T-cell ALL (Choice C). Hematogones (Choice D) are normal precursor B-cells found in bone marrow, but they do not typically present with the clinical features described. B-cell ALL (Choice B) lacks the specific features seen in this case
A 9-year-old boy is being treated for standard-risk acute lymphoblastic leukemia. His treatment protocol calls for administration of intravenous methotrexate and intramuscular L-asparaginase during interim maintenance chemotherapy. What is the most appropriate sequence of drug administration?
- A. Administer L-asparaginase during the methotrexate infusion.
- B. Administer L-asparaginase immediately after the methotrexate infusion.
- C. Administer both drugs at the same time to maximize synergistic activity.
- D. Administer methotrexate 24 hours after the asparaginase.
Correct Answer: B
Rationale: The correct answer is B: Administer L-asparaginase immediately after the methotrexate infusion. This is the most appropriate sequence because methotrexate can impair the activity of L-asparaginase if administered together. By waiting to administer L-asparaginase after the methotrexate infusion, the efficacy of both drugs is maximized without interference. Administering L-asparaginase during the methotrexate infusion (Choice A) would lead to decreased effectiveness of L-asparaginase. Administering both drugs at the same time (Choice C) is not recommended due to potential drug interactions. Administering methotrexate 24 hours after the asparaginase (Choice D) does not optimize the synergistic effects of the drugs during interim maintenance chemotherapy.
A study is designed to investigate the rates of central line–associated blood stream infections among pediatric hematology/oncology patients. Three common central line types (totally implanted catheter [port], peripherally inserted central catheter [PICC], and tunneled externalized catheter [TEC]) were included in the study. What data structure is central line type?
- A. Continuous
- B. Dichotomous
- C. Nominal
- D. Ordinal
Correct Answer: C
Rationale: The correct answer is C: Nominal. The central line type is a categorical variable with no inherent order or ranking. Each type is distinct and cannot be quantitatively ordered or measured. It is not continuous (A), as it is not on a scale. It is not dichotomous (B) as there are more than two categories. It is not ordinal (D) because the types do not have a clear order or ranking. Therefore, central line type is best represented by a nominal data structure.
The nurse assesses a patient who has numerous petechiae on both arms. Which question should the nurse ask the patient?
- A. Do you take salicylates?
- B. Are you taking any oral contraceptives?
- C. Have you been prescribed antiseizure drugs?
- D. How long have you taken antihypertensive drugs?
Correct Answer: A
Rationale: The correct answer is A: Do you take salicylates? Petechiae can be a sign of salicylate use, which can cause bleeding disorders. By asking about salicylates, the nurse can determine if the petechiae are related to medication. Choice B is not directly related to petechiae. Choice C is more specific to antiseizure drugs and not commonly associated with petechiae. Choice D is unrelated to petechiae and focuses on hypertension management. Asking about salicylates is the most appropriate to assess potential medication-induced petechiae.