AUTOSOMAL RECESSIVE POLYCYSTIC DISEASE

OF THE KIDNEY (ARPCDK)

ARPCDK is a rare condition (1:50,000 infants) that usually presents in the fetus around 20 weeks gestation (1) but may occasionally not present until after delivery (1) (neonatal and infantile juvenile form).

PATHOGENESIS

Link to Pathogenesis

CLASSIFICATION

Link to Classification

ULTRASOUND

• Bilateral massively enlarged kidneys (may be seen as early as 16-18 weeks of gestation). A single case of echogenic normal sized kidneys has been reported (2).
• Enlarged kidneys maintain their reniform shape.
• Echogenic (innumerable ectatic collecting tubules result in a multitude of reflective interphases resulting in increased echogenicity).
• Small cysts (1-2mm) may be distributed throughout the parenchyma, however they are not visualized as individual structures.
  Occasionally 8-10mm cysts may be present.
• Severe oligohydramnios (as the kidneys are non functional).
• Absent urinary bladder.
• Hepatic abnormalities (there is an inverse relationship between the degree of hepatic and renal involvement).
• Hepatic cysts.
• Bile duct proliferation.
• Periportal fibrosis (3).

Postnatal renal ultrasound

Postmortem appearance

Pathological specimen of kidneys demonstrating the multiple tiny cysts

REFERENCES

1. Chilton SJ, Cremin BJ. The spectrum of polycystic disease in children. Pediatr Radiol 1981;11:9.
2. Wisser J, Hebisch G, Froster U et.al. Prenatal sonographic diagnosis of autosomal recessive polycystic kidney disease (ARPKD) during the early second trimester. Prenat Diagn 1995;15:868-871.
3. Zerres K, Volpel MC, Weiss H. Cystic kidneys. Genetics, pathologic anatomy, clinical picture and prenatal diagnosis. Hum Genet 1984;68:104-135.