ED patient with hemophilia A after car accident. Which order to implement first?

Correct Answer: B

Rationale: The correct answer is B: Transfuse factor VIII concentrate. In hemophilia A, deficiency of factor VIII leads to impaired blood clotting. Therefore, administering factor VIII concentrate is crucial to control bleeding in this patient. This step takes priority over other options as it addresses the underlying issue of hemophilia A. Choice A is not the priority as stabilizing the patient's bleeding takes precedence over radiography. Choice C is unnecessary until the patient's bleeding is controlled. Choice D, infusing normal saline, does not address the primary concern of bleeding in a hemophiliac patient.

Correct Answer: B

Rationale: The correct answer is B: Valine for glutamic acid. This substitution occurs in sickle hemoglobin, where a single nucleotide change leads to the replacement of glutamic acid by valine at the sixth position of the beta chain. This change results in the characteristic sickling of red blood cells. Choices A, C, and D do not correspond to the specific substitution seen in sickle hemoglobin and are therefore incorrect. It is crucial to understand the molecular basis of the disease to differentiate the correct answer from the distractors.

Correct Answer: C

Rationale: The correct answer is C: Surgical lymph node excision. This is the most appropriate diagnostic test for lymphadenopathy with suspected lymphoma as it provides an adequate tissue sample for definitive diagnosis through histopathological examination. Fine-needle aspirate (B) may not yield enough tissue for accurate diagnosis. Abdominal x-ray (A) and bone scan (D) are not specific for assessing lymphoma and do not provide tissue for histological examination. Surgical excision allows for comprehensive evaluation of the lymph node architecture and cellular characteristics, aiding in accurate diagnosis and treatment planning.

Correct Answer: C

Rationale: The correct answer is C, Aplastic anemia. Aplastic anemia is characterized by pancytopenia, which includes low red blood cell count (MCV 90 fL) and low reticulocyte production index. Thalassemia (A) would typically present with microcytic anemia, not normocytic. Vitamin B12 deficiency (B) would present with macrocytic anemia. Iron deficiency anemia (D) would present with microcytic anemia. Therefore, based on the given data, the most likely cause is aplastic anemia.

Correct Answer: C

Rationale: The correct answer is C: Lymphocyte predominance. Reed-Sternberg cells are characteristic of Hodgkin's lymphoma. In this type, Reed-Sternberg cells are infrequent, and popcorn cells are present. This presentation is typical of lymphocyte predominance subtype. Nodular sclerosis (A) is characterized by bands of collagen separating nodules, mixed cellularity (B) has a mixed cell population with frequent Reed-Sternberg cells, and lymphocyte depleted (D) has few lymphocytes and more Reed-Sternberg cells.