A 36-year-old woman presented with weakness, lassitude, and feeling easily tired. Her bone marrow aspirate showed 15% myeloblasts and reduced erythropoiesis. The most likely cause is

Correct Answer: D

Rationale: The correct answer is D: Myelodysplastic syndrome. Given the patient's age, symptoms, and bone marrow findings of myeloblasts with reduced erythropoiesis, it aligns with the characteristics of myelodysplastic syndrome. This condition involves abnormal blood cell production leading to cytopenias and an increased risk of progression to acute myeloid leukemia. Acute myeloid leukemia (Choice A) typically presents with higher blast percentages and more aggressive symptoms. Acute lymphoid leukemia (Choice B) is less likely due to the presence of myeloblasts in the bone marrow. Myelofibrosis (Choice C) is characterized by fibrosis in the bone marrow, which is not indicated in this case.

Correct Answer: B

Rationale: The correct answer is B: Promastigote. In the laboratory diagnosis of leishmaniasis, the expected parasite stage in vitro is the promastigote form. This is because the promastigote form is the stage of the parasite that lives in the sandfly vector and is transmitted to humans, causing infection. In vitro, the promastigote form can be cultured and studied for diagnostic purposes. Incorrect choices: A: Amastigote - This is the intracellular form of the parasite found in mammalian hosts and not typically used for laboratory diagnosis. C: Trypomastigote - This form is typically associated with Trypanosoma species, not Leishmania. D: Schizont - This term is used for malaria parasites, not Leishmania parasites. In summary, the promastigote form is the most relevant stage for laboratory diagnosis of leishmaniasis due to its presence in the sandfly vector and its ability to

Correct Answer: C

Rationale: The correct answer is C, hereditary spherocytosis. This condition is characterized by a defect in red blood cell membrane proteins, leading to their premature destruction in the spleen, causing splenomegaly. In contrast, chronic renal failure (A) does not typically present with splenomegaly. Aplastic anemia (B) is characterized by bone marrow failure, not splenomegaly. Sickle cell anemia (D) is associated with splenomegaly in early childhood due to sequestration of damaged red blood cells, but splenomegaly usually resolves in later life.

Correct Answer: D

Rationale: The correct answer is D: SLE. Non-thrombocytopenic purpura refers to purpura without low platelet count. In SLE, thrombocytopenia is common, leading to purpura. A: Vasculitis can cause non-thrombocytopenic purpura due to vessel inflammation. B: Uraemia can lead to non-thrombocytopenic purpura due to vascular damage. C: Hereditary haemorrhagic telangiectasia presents with telangiectasias and recurrent epistaxis, not purpura.

Correct Answer: B

Rationale: The correct answer is B: lithium. Lithium is not known to cause haemolytic anemia. Penicillin (A), Quinidine (C), and methyldopa (D) are associated with causing haemolytic anemia due to various mechanisms, such as immune-mediated destruction of red blood cells. In contrast, lithium is primarily used to treat mood disorders and does not have a direct link to causing haemolytic anemia. Therefore, by process of elimination and understanding the pharmacological effects of these drugs, we can determine that lithium is the correct answer.