MRCP Part 1 : Q4-6 : Answers

Question Number 4

Correct Answer: B

Explanation:
Deficiency of B2 is usually found in conjunction with deficiencies of other B vitamins. Isolated deficiency of riboflavin classically produces inflammation of the nasopharyngeal mucosa, cheilosis, angular stomatitis, glossitis, seborrheic dermatitis, and a normochromic, normocytic anemia.

 

Question Number 5

Correct Answer: D

Explanation:
Manifestations of Vitamin K deficiency include hypoprothrombinemia ,hemorrhaagic diathesis, an increased tendency to bleeding and a prolonged coagulation time. Vitamin K is required for gamma-carboxylation of glutamic acid residues of the procoagulant Factors II (prothrombin), VII, IX, and X and the anticoagulant factors protein C and protein S<br>Severe vitamin K deficiency can lead to a hemorrhagic diathesis that is characterized by prolongations of the PT and sometimes also the aPTT. The PT is more sensitive than the aPTT in detecting vitamin K deficiency states because Factor VII, the only one of the vitamin K-dependent factors that is in the extrinsic pathway of coagulation, is the most labile of these proteins.The two major sources of vitamin K are dietary intake and synthesis by the bacterial flora of the intestine. Therefore, in the absence of malabsorption, nutritional deficiency alone rarely causes clinically significant vitamin K deficiency. However, such a condition can arise when eradication of gut flora is combined with inadequate dietary intake. This situation typically occurs in critically ill patients in intensive care units who have no oral intake and are receiving broad-spectrum antibiotics for prolonged periods. Vitamin K deficiency can also develop in patients receiving total parenteral nutrition unless the infusions are supplemented with vitamin K

 

Question Number 6

Correct Answer: B

Explanation:
Diabetic retinopathy may be classified as nonproliferative or proliferative.Nonproliferative diabetic retinopathy is characterized by structural abnormalities of the retinal vessels including edema, exudates, and intraretinal hemorrhages. Proliferative diabetic retinopathy, on the other hand, results in optic disc, retinal, or iris neovascularization.Neovascular tissue contains both a vascular and a fibrous component. The vascular component may cause hemorrhage while the fibrous component may may cause traction on the retina.The major vision-threatening complications therefore include macular edema, macular ischemia, neovascularization with preretinal or vitreous hemorrhage, retinal detachment and neovascular glaucoma.