A longitudinal study of the persistence of increased creatinine and concordance between kidney biomarkers in cats and dogs.

Kidney disease causes morbidity and mortality in dogs and cats. Serum creatinine concentration is an important surrogate marker for glomerular filtration rate (GFR). However, it is not always sensitive to small decreases in kidney function. Efforts to identify additional, more sensitive surrogate markers of GFR to improve detection of early kidney disease has led to the use of symmetrical dimethylarginine (SDMA) in veterinary medicine. There is insufficient information about the behavior of creatinine after an increase and the expected behavior of creatinine and SDMA in these cats and dogs. This study assesses the probability of persistence of increases in creatinine and the subsequent behavior of creatinine and SDMA in animals with persistently increased creatinine. For enrollment, three paired SDMA and creatinine concentrations were required: baseline (T0) with creatinine and SDMA at or below the upper reference limit (URL), T1, and T2 0.5-18 months after T1. The study included 4517 cats and 4576 dogs with increased T1 creatinine concentrations and 54,295 cats and 125,403 dogs with T1 creatinine at or below the URL. The probability of a persistently increased creatinine at T2 was approximately 58% for cats and 49% for dogs after a T1 increase. For animals without a T1 increase the probability of increased creatinine at T2 was only 7% for cats and 3% for dogs. For cats and dogs with persistently increased Cr, the probability of an increased SDMA concentration at T1 was 70-75%. By 24 months, that probability rose to 94% for cats and 88% for dogs.

Longitudinal evaluation of symmetric dimethylarginine and concordance of kidney biomarkers in cats and dogs.

Symmetric dimethylarginine (SDMA) is a sensitive surrogate marker for glomerular filtration rate; however, there are uncertainties as to how to interpret mild increases (SDMA 15-19 µg/dL). This descriptive study used retrospective data to evaluate whether cats or dogs that had initial SDMA values (at T0) within the reference interval followed by an increased SDMA (at T1) had persistently increased SDMA (at T2; measured from 14 days to 18 months following T1; Persistence Cohort), and if and when cats or dogs with persistently increased SDMA had increased creatinine up to 24 months (Concordance Cohort). The Persistence Cohort included 16,670 cats and 16,712 dogs. If SDMA at T1 was 15-19 µg/dL, the probability of persistence was 53% for cats and 42% for dogs, while creatinine was concurrently increased in 20% of cats and 18% of dogs. For comparison, if SDMA was not increased at T1 the probability of increased SDMA at recheck was only 20% for cats and 9% for dogs. For cats and dogs with a T1 SDMA of 15-19 µg/dL and with persistent increases at T2, the probability of increased creatinine at T1 was 20% for cats and 18% for dogs, rising to 61% and 55%, respectively, by 24 months. When SDMA at T1 was >25 µg/dL, creatinine was increased in 93% of cats and 92% of dogs by 24 months. Mildly increased SDMA results may provide an opportunity to identify some cats and dogs earlier in their kidney disease.

Scribner shunt conversion to arteriovenous fistula.

Scribner shunts were converted to arteriovenous fistulas in twenty-six patients, with long-term success in twenty patients. Infection with loss of the fistula was a problem in two patients. The fistulas were used for home as well as center dialysis and as a primary blood access site as well as a backup site.

Transluminal angioplasty versus surgical repair for stenosis of hemodialysis grafts. A randomized study.

A randomized study of transluminal angioplasty versus surgical revision for stenosis at the venous end of hemodialysis grafts was carried out. Median patency for the surgical group was 12 months versus only 4 months for the transluminal angioplasty group. This difference was statistically significant (p less than 0.01). In addition, the average cost for surgical revision was slightly less than that for transluminal angioplasty. Therefore, for long-term patency, surgical treatment is the method of choice, although under special circumstances there may still be a role for transluminal angioplasty.