Hereditary kidney disease characterized by the formation of multiple bilateral renal cysts from an early age. The cysts grow progressively, destroy functional parenchyma and progress to chronic kidney failure in adulthood. It is one of the most prevalent and best-characterized feline genetic diseases. The feline form is homologous to human autosomal dominant polycystic kidney disease type 1. The PCR test specifically detects the known variant of the PKD1 gene.

Historically up to 35-45% of Persians in ultrasound studies from the 1990s, before genetic screening. Breeds with Persian ancestry (Exotic Shorthair, British Shorthair, Sacred Birman, Ragdoll, Scottish Fold, Selkirk Rex) show lower but documented prevalences. Limited data in breeds such as Kartäuser, Chartreux or Russian Blue, where it is included as a precaution due to possible Persian introgression.

- Multiple bilateral renal cysts visible on ultrasound from 8-10 weeks of age\n- Progressive increase in kidney size\n- Chronic kidney failure in adulthood (mean around 7 years, with a wide range)\n- Polydipsia and polyuria in advanced stages\n- Weight loss, anorexia, vomiting and pale mucous membranes\n- Concurrent hepatic cysts in a proportion of cases

The disease was described in the Persian in the last decades of the 20th century and its autosomal dominant inheritance was demonstrated through genealogical and ultrasound studies. Series from the 1990s showed ultrasound prevalences close to 40% in some Persian populations, making it the most frequent hereditary disease of the breed. In the mid-2000s Leslie Lyons' group identified the causal variant in the PKD1 gene, the homologue of the human gene responsible for human PKD1. The development of the PCR test enabled assisted screening in Persians and derived breeds. Prevalence has decreased notably in controlled populations, although it persists in unscreened lines.

- Screen all breeding animals before the first mating\n- Do not cross two carriers (heterozygotes): risk of severely affected homozygous offspring\n- A heterozygote can be mated with a free individual, but carrier offspring must be informed and, preferably, not intended for breeding\n- The medium-term goal is not to use carriers as breeding animals, but without collapsing the genetic variability of the breed: retire them in a planned manner\n- Complement genetics with renal ultrasound in adults to quantify the cystic burden

The genetic test detects only the known variant of PKD1, so a negative result does not rule out other cystic nephropathies. Renal ultrasound remains useful in adults to quantify the cystic burden and refine the prognosis. Differential diagnosis with simple acquired cysts, renal neoplasia and other hereditary nephropathies. Concurrent hepatic cysts are usually clinically silent.

1. Lyons LA et al. 2004, mutación de la enfermedad renal poliquística felina identificada en PKD1 (PMID 15466259)
2. Lyons LA et al. 2005, la poliquistosis renal felina está ligada a la región PKD1 (PMID 15674734)
3. PKD1 y caracterización ecográfica en gatos con quistes renales (PMID 39108347)
4. Prevalencia de la mutación PKD1 en gatos persas y relacionados (PMID 32687010)
5. OMIA:000807 Enfermedad renal poliquística felina