A3 week old child presents with an abdominal mass. What is the most common cause of the presentation?
Neuroblastoma
Wilms tumor
Multicystic dysplastic kidney
Distended bladder
Ans. is 'c' i.e., Multicystic dysplastic kidney Multicystic renal dysplasia (multicystic dysplastic kidney)* Multicystic dysplastic kidney is a congenital condition in which the entire kidney is dysplastic with a preponderance of cysts.* It can result from ureteral atresia. Kidney size is highly variable.* Kidney is replaced by multiple cysts of varying sizes that do not communicate and no identifiable parenchyma is present.* MCDK usually is unilateral and generally is not inherited. Bilateral MCDKs are incompatible with life.* Contralateral vesicouretral reflux is present in 15% cases. Contralateral hydronephrosis is present in 5 - 10% cases.* It is the most common cause of an abdominal mass, but the vast majority are nonpalpable at birth and it is the most common cystic disease in neonates.* In most cases, it is discovered incidentally during prenatal sonography.* In some patients, the cysts are identified prenatally, but the cysts regress in utero and no kidney is identified on imaging at birth.* Sonography shows the characteristic appearance of a kidney replaced by multiple cysts of varying sizes that do not communicate, and no identifiable parenchyma is present
Kidney