Mr XY was found to be anemic. During history taking, he informed his doctor that he was a strict vegetarian who did not consume any meat, fish or milk products.

Correct Answer: B

Rationale: Correct Answer: B (Vitamin B12 deficiency) Rationale: 1. Mr. XY is a strict vegetarian, avoiding meat, fish, and milk products. 2. Vitamin B12 is mainly found in animal products, crucial for red blood cell production. 3. Vegetarians at risk of B12 deficiency due to limited dietary sources. 4. Anemia can result from B12 deficiency, leading to decreased red blood cell production. Summary: A: Iron deficiency - Possible but less likely since vegetarian diets can still provide iron. C: Defects in erythropoietin production - Unrelated to diet, more related to kidney function. D: Calcium-deficiency - Not directly related to anemia; more associated with bone health.

Correct Answer: D

Rationale: The correct answer is D: Infectious mononucleosis. Dohle bodies are seen in infectious mononucleosis due to the accumulation of rough endoplasmic reticulum in neutrophils. This is a result of the viral infection causing stress on the neutrophils. In chronic myeloid leukemia (A), leukemoid reaction (B), and Chediak-Higashi syndrome (C), Dohle bodies are not typically observed. In chronic myeloid leukemia, the characteristic finding is the Philadelphia chromosome. Leukemoid reaction is a reactive increase in white blood cells due to infection or inflammation. Chediak-Higashi syndrome is a rare autosomal recessive disorder characterized by defective phagolysosome formation.

Correct Answer: C

Rationale: The correct answer is C because Anopheles balabacensis, the main vector transmitting malaria in Sabah, breeds in temporary water collections in jungles. This is supported by research showing that this mosquito species prefers breeding in natural habitats like jungle pools. Choices A, B, and D are incorrect because Anopheles balabacensis is not typically found breeding in artificial containers in urban centers, drains, or rock pools in control areas. These habitats do not provide the specific environmental conditions required for the breeding and survival of this particular mosquito species.

Correct Answer: D

Rationale: The correct answer is D: haemolysis. In thalassemia, there is an increased breakdown of red blood cells leading to excessive production of bilirubin causing jaundice. Viral hepatitis B and C do not directly cause jaundice in thalassemia. Iron deposition in the liver is seen in iron overload conditions like hemochromatosis, not thalassemia. Haemolysis in thalassemia is the primary reason for jaundice.

Correct Answer: C

Rationale: Basophilic stippling is caused by the presence of ribosomal RNA in red blood cells, which is a characteristic finding in chronic lead poisoning. Lead inhibits enzymes involved in heme synthesis, leading to accumulation of ribosomal RNA. In CML, there is an increase in immature white blood cells, not red blood cells. Myelosclerosis is associated with bone marrow fibrosis, not basophilic stippling. Iron deficiency anemia presents with microcytic, hypochromic red blood cells, not basophilic stippling.