A patient with cystic fibrosis (CF) presents with recurrent pulmonary exacerbations characterized by increased sputum production, cough, and fever. Which of the following treatments is most effective for addressing the underlying pathophysiology of CF and preventing disease progression?

Correct Answer: B

Rationale: The most effective treatment for addressing the underlying pathophysiology of cystic fibrosis (CF) and preventing disease progression is the use of mucolytic agents, such as dornase alfa. CF is a genetic disorder that leads to the production of thick, sticky mucus in the respiratory tract. This mucus buildup can obstruct airways, lead to recurrent infections, and contribute to pulmonary exacerbations. Mucolytic agents work by reducing the viscosity of the mucus, making it easier to clear from the airways. This helps to improve lung function, reduce the frequency of exacerbations, and slow down disease progression in CF patients. Inhaled corticosteroids may be used for managing airway inflammation, but they do not target the underlying mucus production in CF. Antibiotic therapy is important for treating respiratory infections in CF patients, but it does not address the primary

Correct Answer: A

Rationale: The patient's presentation with fatigue, pallor, dyspnea on exertion, low hemoglobin level, decreased MCV, and decreased MCHC are all consistent with iron deficiency anemia. Iron deficiency anemia is the most common type of anemia and occurs when there is insufficient iron available for hemoglobin production. The low hemoglobin level results in symptoms such as fatigue and pallor, while the decreased MCV and MCHC indicate microcytic and hypochromic red blood cells, respectively, which are characteristic of iron deficiency anemia. Vitamin B12 deficiency anemia and thalassemia typically present with a different pattern of laboratory findings and clinical manifestations. Sickle cell anemia is characterized by sickle-shaped red blood cells due to a genetic mutation, and the laboratory findings in sickle cell anemia are different from those seen in the patient described in this scenario.

Correct Answer: D

Rationale: The patient is presenting with symptoms and laboratory findings consistent with a paraneoplastic syndrome related to Hodgkin lymphoma. In this case, the fever, chills, generalized malaise, pancytopenia, circulating Reed-Sternberg cells, and bone marrow involvement are all indicative of a paraneoplastic syndrome associated with Hodgkin lymphoma. Paraneoplastic syndromes are a group of disorders that are triggered by an abnormal immune response to a neoplasm, such as Hodgkin lymphoma, leading to various systemic manifestations.

Correct Answer: B

Rationale: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive disorder that leads to hemolytic anemia in response to oxidative stress. The patient's presentation of fatigue, weakness, and jaundice along with laboratory findings of hemolytic anemia (evidenced by schistocytes), elevated LDH, and decreased haptoglobin are all characteristic of G6PD deficiency. The oxidative stress causes red blood cell destruction, resulting in the release of LDH and bilirubin, leading to jaundice. Decreased haptoglobin is seen due to its consumption in binding free hemoglobin released from the lysed red blood cells. Additionally, the presence of schistocytes on a peripheral blood smear is indicative of red blood cell fragmentation, a common finding in hemolytic anemias including G6PD deficiency

Correct Answer: D

Rationale: The presentation of sudden-onset severe headache, vomiting, and altered mental status, along with the presence of a berry-shaped aneurysm on imaging, point towards a diagnosis of subarachnoid hemorrhage. The most common cause of a subarachnoid hemorrhage is the rupture of a saccular (berry) aneurysm, which commonly occurs at the junction of the anterior communicating artery and anterior cerebral artery. The sudden headache is often described as the "worst headache of my life" and is typically associated with nausea and vomiting. Altered mental status may be present due to the effects of increased intracranial pressure and possible associated brain injury. It is important to promptly diagnose and manage subarachnoid hemorrhage to prevent complications such as vasospasm, rebleeding, and ischemic deficits.