Pathophysiology Practice Questions

Correct Answer: D

Rationale: The correct answer is D. Hemangiomas, congenital dermal melanocytosis (i.e., Mongolian spots), and macular stains are birthmarks that usually fade or regress as the child gets older. Hemangiomas are vascular birthmarks that often shrink and fade over time. Congenital dermal melanocytosis (Mongolian spots) are blue-gray birthmarks commonly found on the lower back and buttocks of infants, which typically fade by adolescence. Macular stains, also known as salmon patches, are pink or red birthmarks that usually fade within the first few years of life. Choice D is correct because all the mentioned birthmarks tend to diminish as the child grows, unlike choices A, B, and C which do not fade or regress with age.

Correct Answer: D

Rationale: The man's presentation of large, hard nodules around his toes and elbows is indicative of tophi formation, which is characteristic of chronic gout. Tophi are deposits of uric acid crystals that can develop over time in untreated or poorly managed gout. During the chronic phase of gout, tophi can form in joints, soft tissues, and organs. Asymptomatic refers to a phase where there are no symptoms present. Acute flare is characterized by sudden and severe joint pain and inflammation. The intercritical period is the time between gout attacks when the patient is symptom-free.

Correct Answer: B

Rationale: In peripheral artery disease, pain in the lower extremities worsens with the elevation of the extremity because it diverts blood flow away from the affected area, exacerbating the pain. Choices A, C, and D are incorrect. Resting doesn't increase blood flow, a dependent position doesn't lead to blood pooling in this context, and pain worsening due to touch or massage is not a typical feature of peripheral artery disease.

Correct Answer: B

Rationale: The scenario describes a 45-year-old woman with fatigue, weight gain, cold intolerance, low T3 and T4 levels, and elevated TSH levels, which are indicative of hypothyroidism. In hypothyroidism, there is decreased production of thyroid hormones (T3 and T4) leading to elevated TSH levels as the pituitary gland tries to stimulate the thyroid gland to produce more hormones. Therefore, the correct answer is hypothyroidism (Choice B). Choice A, Hyperthyroidism, is incorrect as the patient's symptoms and thyroid function tests point towards decreased thyroid hormone levels, which is characteristic of hypothyroidism, not hyperthyroidism. Choice C, Euthyroid sick syndrome, is incorrect because this condition typically presents with normal to low T3 and T4 levels in the setting of non-thyroid illness, unlike the elevated TSH levels observed in this case. Choice D, Subclinical hyperthyroidism, is also incorrect as the patient has low T3 and T4 levels, which is not consistent with hyperthyroidism, whether clinical or subclinical.

Correct Answer: B

Rationale: In chronic kidney disease, anemia commonly occurs due to decreased erythropoietin production. Erythropoiesis-stimulating agents, such as erythropoietin or darbepoetin, are the mainstay of treatment to stimulate red blood cell production. Iron supplementation is more appropriate for iron-deficiency anemia, not the anemia of chronic kidney disease. Blood transfusion is reserved for severe cases or acute blood loss. Vitamin B12 supplementation is indicated for megaloblastic anemia caused by vitamin B12 deficiency, not specifically in chronic kidney disease-related anemia.