This is intended to provide a quick list for diagnosis of HRS, since HRS is a diagnosis of exclusion and should only be made once other conditions are “ruled out.” HRS is a clinical diagnosis, and there is no one perfectly sensitive or specific test. But if your patient meets these criteria, you should be worried.
- Ascites is present
- There is an AKI (creatinine >1.5)
- Rule out infection: there is no UTI or pyelonephritis
- Rule out prerenal injury: there is no improvement in serum Cr after resuscitation with 2 days of 1 mg/kg albumin, 100 g max
- Rule out intrinsic disease: there is no hematuria (>50 RBCs) or proteinuria (>0.5 g) to suggest renal disease
- Rule out meds: no nephrotoxic meds recently given
- Rule out hypotension/ATN: no signs of ATN in the urine, no shock or profound hypotension
In the past, there were minor criteria including oliguria (<0.5 L urine output/day), low urine sodium (<20), and low serum sodium. These were found to have poor specificity and were dropped in 2007.
There are two types of HRS: Type 1 is rapid (develops in <2 weeks) and severe, with a 10% survival rate over 3 months. Type 2 is more gradual and on a spectrum with diuretic-resistant ascites.
You should also ask yourself: what triggered this episode of HRS? Common precipitants include infection (check a chest x-ray for pneumonia, urine studies for UTI, blood cultures, and rule out SBP), prerenal causes (not giving enough albumin after large-volume paracentesis, diuretics), post-TIPS, and nephrotoxic drugs.