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
Cystic diseases of kidney are all except: 
Select and explain. 
A. Medullary sponge kidney, B. Nephrophthisis, C. Horseshoe kidney, D. Glomerulocystic disease
C: Horseshoe kidney
Answer: C: Horseshoe kidney 
Explanation: Horseshoe Kidney Fusion of the upper (10%) or lower poles (90%) of the kidneys Continuous across the midline anterior to the great vessels. Congenital renal anomaly not a cystic disease. Cystic lesions of kidney are: Polycystic kidney disease Autosomal dominant (adult) polycystic disease Autosomal recessive (childhood) polycystic disease Medullary cystic disease Medullary sponge kidney Nephronophthisis Glomerulocystic disease Extraparenchymal renal cysts (pyelocalyceal cysts, hilar lymphangitic cysts)