This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Polycystic Kidney Disease, Subject name: Pathology
[{'content': 'Which of the following statement are true regarding autosomal dominant polycystic kidney disease (ADPKD)? \nSelect and explain. \nA. Bilateral kidneys are enlarged, B. External surface show numerous cyst of 3-4 cm in diameter, C. Histology shows functioning nephrons dispersed between the cysts, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Autosomal dominant polycystic kidney disease (ADPKD) Kidneys are bilaterally enlarged External surface appears to be composed solely of a mass of cysts, up to 3 to 4 cm in diameter, with no intervening parenchyma. Microscopic examination - Functioning nephrons dispersed between the cysts. The cysts may be filled with a clear, serous fluid or with turbid, red to brown, sometimes hemorrhagic fluid. Cysts may arise at any level of the nephron, from tubules to collecting ducts, and therefore they have a variable, often atrophic lining. PKD1 gene implicated in 85% of cases.PKD1, on 16p, is the defective gene. This gene encodes polycystin-1. PKD2 gene, implicated in 10% to 15% of cases, resides on chromosome 4 and encodes polycystin-2.', 'role': 'assistant'}]