ATI RN
Anatomy of Hematologic System Questions
Question 1 of 5
A study is designed to investigate the rates of central line–associated blood stream infections (CLABSI) among pediatric hematology/oncology patients. Investigators wish to compare the length of stay (LOS) between subjects receiving three common central line types (totally implanted catheter [port], peripherally inserted central catheter [PICC], and tunneled externalized catheter [TEC]). It is discovered that LOS is not normally distributed. What is the appropriate test for comparing the LOS between patients receiving the three central line types?
Correct Answer: D
Rationale: The correct answer is D: Kruskal-Wallis test. Since the LOS data is not normally distributed, parametric tests like Student's t test and ANOVA are not appropriate. The Kruskal-Wallis test is a non-parametric test used to compare three or more independent groups when the data is not normally distributed. It ranks the LOS values across the three central line types and tests whether there are differences in medians. The Wilcoxon-Mann-Whitney test (choice C) is used for comparing two independent groups, not three. Therefore, it is not the appropriate test in this scenario.
Question 2 of 5
A young child with consanguineous parents has developmental delay and a history of multiple recurrent bacterial infections and short stature. He presents to the emergency department following trauma and requires a blood transfusion. Blood work identifies leukocytosis, neutrophilia, and the Bombay blood group (absent H antigen as well as absent A and B antigens). What is this patient's diagnosis?
Correct Answer: B
Rationale: The correct answer is B: Leukocyte adhesion deficiency (LAD) Type II. This diagnosis is supported by the patient's history of recurrent bacterial infections, leukocytosis, neutrophilia, and the Bombay blood group. LAD Type II is characterized by a defect in the CD18 integrin molecules, leading to impaired leukocyte adhesion and migration to sites of infection. The Bombay blood group is due to the absence of H antigen, which is also seen in LAD Type II. A: Chediak-Higashi syndrome is characterized by recurrent infections, albinism, and peripheral neuropathy, not leukocyte adhesion deficiency. C: CD18 deficiency is actually another term for LAD Type I, not LAD Type II. D: Griscelli syndrome presents with silvery hair and immunodeficiency, but does not involve leukocyte adhesion deficiency.
Question 3 of 5
Which statement is correct regarding lymphocyte counts in infants versus adults?
Correct Answer: C
Rationale: The correct answer is C because T-cell numbers in infants are indeed higher than in adults. This is due to the active development of the immune system in infants, leading to a higher proportion of T-cells. A is incorrect because NK-cell numbers in infants are actually higher at birth and decrease with age. B is incorrect because B-cell numbers are lower at birth and increase with age. D is incorrect because infants do not have low lymphocyte counts; their immune system is actively developing, leading to higher lymphocyte counts compared to adults.
Question 4 of 5
A 2-year-old girl has a diagnosis of overall stage IV favorable histology Wilms' tumor with pulmonary metastases and local stage III disease due to finding positive lymph nodes. After she completes 6 weeks of vincristine/dactinomycin/doxorubicin (DD4A) chemotherapy, restaging shows complete resolution of some but not all lung nodules. Tumor genetic testing reveals combined loss of heterozygosity for 1p and 16q. Which of the following would be the most appropriate treatment plan?
Correct Answer: D
Rationale: The correct answer is D because the addition of cyclophosphamide and etoposide to the chemotherapy regimen is indicated for patients with combined loss of heterozygosity for 1p and 16q in Wilms' tumor. This genetic abnormality is associated with a higher risk of relapse and poorer outcomes. The extended duration of chemotherapy (33 weeks) is necessary to target any remaining tumor cells and reduce the risk of recurrence. Additionally, the decision to administer radiation to both the lungs and flank is appropriate given the incomplete resolution of some lung nodules after initial chemotherapy. Lung radiation helps to target any remaining metastatic lesions, while flank radiation targets the primary tumor site and positive lymph nodes. This comprehensive treatment approach aims to maximize the chances of long-term disease control and survival for the patient. Choice A is incorrect because it lacks the addition of cyclophosphamide and etoposide, which are needed for Wilms' tumor with the specific genetic abnormality mentioned.
Question 5 of 5
You have a new patient consult in clinic this morning. The referral packet includes the newborn screen report, which is flagged abnormal hemoglobinopathy screen, F, A, Bart's, refer to hematology, and a complete blood count done at 4 years of age with a hemoglobin of 10 g/dL and an MCV of 68. The pediatrician has informed the parents the child has some form of alpha thalassemia. The older brother had the same newborn screen results but had a normal complete blood count when checked. The mother wants to know why her second child has an abnormal complete blood count when she and her husband do not have any blood problems. How would you respond to the child's mother?
Correct Answer: A
Rationale: Rationale for correct answer A: 1. Both parents must be carriers for the child to have alpha thalassemia. 2. The child has an abnormal complete blood count, indicating a hemoglobinopathy. 3. The child inherited a trans-deletion genotype alpha thalassemia trait from both parents. 4. Silent carriers have no symptoms but can pass on the trait. Summary for incorrect choices: B: In cis deletion, both parents would have to pass on the trait, which is not the case here. C: Spontaneous mutation is unlikely for alpha thalassemia. D: Both parents having cis deletions would result in a more severe form of alpha thalassemia.