CKD Staging in Cats: IRIS Guidelines and Welfare

The IRIS staging system for feline chronic kidney disease guides treatment decisions and enables monitoring of disease progression and quality of life.

Key Facts

IRIS (International Renal Interest Society) staging classifies CKD into stages 1-4 based on creatinine and SDMA
Stage 1 is non-azotemic with other kidney abnormalities; Stage 4 represents severe azotemia
Substaging by proteinuria and blood pressure identifies additional treatment targets
SDMA is a more sensitive early marker than creatinine, detecting CKD earlier in disease course
Staging guides the intensity of monitoring and treatment at each disease stage
Quality of life alongside IRIS stage guides end-of-life decision making
Cats may remain at stable IRIS stages for months to years with appropriate management

Welfare Considerations

IRIS staging provides a common language for tracking CKD progression and calibrating intervention intensity. Cats at Stage 1-2 benefit from dietary management and monitoring; Stage 3-4 cats need more active treatment to manage uremic signs, hypertension, and anemia. Welfare assessment must accompany staging - a stable Stage 3 cat with excellent quality of life warrants continued treatment, while a declining Stage 2 cat may warrant more intensive support. Numbers inform but do not replace clinical judgment.

What You Can Do

Ask your vet to IRIS-stage your cat's CKD and explain what the stage means for management
Schedule monitoring frequency appropriate to your cat's IRIS stage
Measure blood pressure alongside kidney function - hypertension worsens CKD progression
Assess quality of life regularly using validated feline QoL tools
Revisit treatment goals as IRIS stage changes or quality of life declines