pediatrics
Renal Anomalies
Autosomal recessive polycystic kidney disease
 gene, located in chromosome 6p21. In contrast, Autosomal Dominant Polycystic Kidney Disease (ADPKD) is much more common, occurring in about 1/500 to 1/1000 live births. Symptoms of autosomal dominant polycystic kidney disease are usually not present until adulthood. Rarely, symptoms manifest in infancy in the more aggressive form. Children may be diagnosed earlier when a cyst is found incidentally or via family history. Autosomal recessive polycystic kidney disease affects the Kidneys Liver The kidneys are usually greatly enlarged and contain small cysts; renal failure is common in childhood. The liver is enlarged and has periportal fibrosis, bile duct proliferation, and scattered cysts; the remainder of the hepatic parenchyma is normal. Fibrosis causes portal hypertension by age 5 to 10 years, but hepatic function is normal or minimally impaired. Disease severity and progression vary. Severe disease may manifest prenatally or soon after birth or in early childhood with renal-related symptoms; less severely affected patients present in late childhood or adolescence with hepatic-related symptoms. Affected neonates have a protuberant abdomen with huge, firm, smooth, symmetric kidneys. Severely affected neonates commonly have pulmonary hypoplasia secondary to the in utero effects of renal dysfunction and oligohydramnios. In patients aged 5 to 10 years, signs of Portal Hypertension , such as esophageal and gastric varices and hypersplenism, occur. If the patient presents in adolescence, nephromegaly is less marked, renal insufficiency may be mild to moderate, and the major symptoms are those related to portal hypertension. Diagnosis of autosomal recessive polycystic kidney disease may be difficult, especially without a family history. Ultrasonography may show renal or hepatic cysts; definitive diagnosis may require biopsy. Ultrasonography in late pregnancy usually allows presumptive in utero diagnosis. If postnatal ultrasonography is not definitive, MRI or CT may be diagnostic. If needed, molecular testing forPKHD1can be done when clinical criteria is not met. Many neonates die in the first few days or weeks of life from pulmonary insufficiency. Most who survive develop progressive renal failure often requiring renal replacement therapy. Experience with renal transplantation with or without hepatic transplantation is limited. When transplantation is done, Hypersplenism must be controlled to obviate difficulty with hypersplenism-induced leukopenia, which increases the risk of systemic infection. Portal hypertension may be treated by portacaval or splenorenal shunts, which reduce morbidity but not mortality. 