Objective—To determine whether nephrolithiasis was associated with an increase in mortality rate or in the rate of disease progression in cats with naturally occurring stage 2 (mild) or 3 (moderate) chronic kidney disease.
Design—Retrospective case-control study.
Animals—14 cats with stage 2 (mild) or 3 (moderate) chronic kidney disease (7 with nephroliths and 7 without).
Procedures—All cats were evaluated every 3 months for up to 24 months. Possible associations between nephrolithiasis and clinicopathologic abnormalities, incidence of uremic crises, death secondary to renal causes, and death secondary to any cause were evaluated.
Results—There were no clinically important differences in biochemical, hematologic, or urinalysis variables between cats with and without nephroliths at baseline or after 12 and 24 months of monitoring. No associations were detected between nephrolithiasis and rate of disease progression, incidence of uremic crises, or death.
Conclusions and Clinical Relevance—Results suggested that in cats with mild or moderate chronic kidney disease, nephrolithiasis was not associated with an increase in mortality rate or in the rate of disease progression. Findings support recommendations that cats with severe kidney disease and nephrolithiasis be managed without surgery.
Objective—To identify risk factors associated with diagnosis of chronic kidney disease (CKD) in cats.
Design—Retrospective case-control study.
Animals—1,230 cats with a clinical diagnosis of CKD, serum creatinine concentration > 1.6 mg/dL, and urine specific gravity < 1.035 and 1,230 age-matched control cats.
Procedures—Data on putative risk factors for CKD were extracted for multivariate logistic regression analysis from the medical records of cats brought to 755 primary care veterinary hospitals. For a subset of cats evaluated 6 to 12 months prior to the date of CKD diagnosis or control group inclusion, the percentage change in body weight between those dates as well as clinical signs at the earlier date were analyzed for associations with CKD development.
Results—Risk factors for CKD in cats included thin body condition, prior periodontal disease or cystitis, anesthesia or documented dehydration in the preceding year, being a neutered male (vs spayed female), and living anywhere in the United States other than the northeast. The probability of CKD decreased with increasing body weight in nondehydrated cats, domestic shorthair breed, and prior diagnosis of diabetes mellitus and increased when vomiting, polyuria or polydipsia, appetite or energy loss, or halitosis was present at the time of diagnosis or control group inclusion but not when those signs were reported 6 to 12 months earlier. Median weight loss during the preceding 6 to 12 months was 10.8% and 2.1% in cats with and without CKD, respectively.
Conclusions and Clinical Relevance—The probability of CKD diagnosis in cats was influenced by several variables; recent weight loss, particularly in combination with the other factors, warrants assessment of cats for CKD.
Objective—To determine whether a renal diet modified in protein, phosphorus, sodium, and lipid content was superior to an adult maintenance diet in minimizing uremic episodes and mortality rate in cats with stage 2 or 3 chronic kidney disease (CKD).
Animals—45 client-owned cats with spontaneous stage 2 or 3 CKD.
Procedures—Cats were randomly assigned to an adult maintenance diet (n = 23 cats) or a renal diet (22) and evaluated trimonthly for up to 24 months. Efficacy of the renal diet, compared with the maintenance diet, in minimizing uremia, renal-related deaths, and all causes of death was evaluated.
Results—Serum urea nitrogen concentrations were significantly lower and blood bicarbonate concentrations were significantly higher in the renal diet group at baseline and during the 12- and 24-month intervals. Significant differences were not detected in body weight; Hct; urine protein-to-creatinine ratio; and serum creatinine, potassium, calcium, and parathyroid hormone concentrations. A significantly greater percentage of cats fed the maintenance diet had uremic episodes (26%), compared with cats fed the renal diet (0%). A significant reduction in renal-related deaths but not all causes of death was detected in cats fed the renal diet.
Conclusions and Clinical Relevance—The renal diet evaluated in this study was superior to an adult maintenance diet in minimizing uremic episodes and renalrelated deaths in cats with spontaneous stage 2 or 3 CKD.
Objective—To determine whether high systolic blood
pressure (SBP) at the time of initial diagnosis of
chronic renal failure in dogs was associated with
increased risk of uremic crisis, risk of dying, or rate of
decline in renal function.
Design—Prospective cohort study.
Animals—45 dogs with spontaneous chronic renal
Procedure—Dogs were assigned to 1 of 3 groups on
the basis of initial SBP (high, intermediate, low);
Kaplan-Meier and Cox proportional hazards methods
were used to estimate the association between SBP
and development of a uremic crisis and death. The
reciprocal of serum creatinine concentration was
used as an estimate of renal function.
Results—Dogs in the high SBP group were more
likely to develop a uremic crisis and to die than were
dogs in the other groups, and the risks of developing
a uremic crisis and of dying increased significantly as
SBP increased. A greater decrease in renal function
was observed in dogs in the high SBP group.
Retinopathy and hypertensive encephalopathy were
detected in 3 of 14 dogs with SBP ≥ 180 mm Hg.
Systolic blood pressure remained high in 10 of 11
dogs treated with antihypertensive drugs.
Conclusions and Clinical Relevance—Results suggested
that initial high SBP in dogs with chronic renal
failure was associated with increased risk of developing
a uremic crisis and of dying. Further studies are
required to determine whether there is a cause-and-effect
relationship between high SBP and progressive
renal injury and to identify the risks and benefits of
antihypertensive drug treatment. (J Am Vet Med Assoc 2003;222:322–329)
Objective—To determine frequency of urinary tract
infection (UTI) among dogs with pruritic disorders that
were or were not receiving long-term glucocorticoid
Animals—127 dogs receiving glucocorticoids for > 6
months and 94 dogs not receiving glucocorticoids.
Procedure—Bacterial culture of urine samples was
performed in dogs receiving long-term glucocorticoid
treatment, and information was collected on drug
administered, dosage, frequency of administration,
duration of glucocorticoid treatment, and clinical signs
of UTI. For dogs not receiving glucocorticoids, a single
urine sample was submitted for bacterial culture.
Results—Multiple (2 to 6) urine samples were submitted
for 70 of the 127 (55%) dogs receiving glucocorticoids;
thus, 240 urine samples were analyzed. For
23 of the 127 (18.1%) dogs, results of bacterial culture
were positive at least once, but none of the dogs had
clinical signs of UTI. Pyuria and bacteriuria (present vs
absent) were found to correctly predict results of bacterial
culture for 89.9% and 95.8% of the samples,
respectively. Type of glycocorticoid, dosage, frequency
of administration, and duration of treatment were not
associated with frequency of UTI. None of the urine
samples from dogs not receiving glucocorticoids yielded
bacterial growth. The frequency of UTI was significantly
higher for dogs treated with glucocorticoids
than for dogs that had not received glucocorticoids.
Conclusions and Clinical Relevance—Results suggest
that dogs receiving long-term glucocorticoid
treatment have an increased risk of developing a UTI.
On this basis, we recommend that urine samples be
submitted for bacterial culture at least yearly for such
dogs. (J Am Vet Med Assoc 2005;227:239–243)
Objective—To determine whether urine protein-to-creatinine
ratio (UP:C) ≥ 1.0 at initial diagnosis of
chronic renal failure (CRF) is associated with greater
risk of development of uremic crises, death, and progression
of renal failure in dogs.
Design—Prospective cohort study.
Animals—45 dogs with CRF.
Procedure—Dogs were prospectively assigned to 2
groups on the basis of initial UP:C < 1.0 or ≥ 1.0. The
association between magnitude of proteinuria and
development of uremic crises and death was determined
before and after dogs with initial UP:C ≥ 1.0
were assigned to 3 subgroups and compared with
dogs with initial UP:C < 1.0. Changes in reciprocal
serum creatinine concentration were used to estimate
decrease in renal function.
Results—Initially, dogs had similar clinical characteristics
with the exception of systolic blood pressure
and UP:C. Relative risks of development of uremic
crises and death were approximately 3 times higher
in dogs with UP:C ≥ 1.0, compared with dogs with
UP:C < 1.0. Relative risk of adverse outcome was
approximately 1.5 times higher for every 1-unit increment
in UP:C. The decrease in renal function was of
greater magnitude in dogs with UP:C ≥ 1.0, compared
with dogs with UP:C < 1.0.
Conclusions and Clinical Relevance—Initial UP:C
≥ 1.0 in dogs with CRF was associated with greater
risk of development of uremic crises and death, compared
with dogs with UP:C < 1.0. Initial determinations
of UP:C in dogs with naturally occurring CRF
may be of value in refining prognoses. (J Am Vet Med
Objective—To determine whether a diet used for
dogs with renal failure (renal food [RF]) was superior
to an adult maintenance food (MF) in minimizing uremic
crises and mortality rate in dogs with spontaneous
chronic renal failure.
Animals—38 dogs with spontaneous chronic renal
Procedure—Dogs were randomly assigned to a group
fed adult MF or a group fed RF and evaluated for up to
24 months. The 2 groups were of similar clinical, biochemical,
and hematologic status. The effects of diets
on uremic crises and mortality rate were compared.
Changes in renal function were evaluated by use of serial
evaluation of serum creatinine concentrations and
reciprocal of serum creatinine concentrations.
Results—Compared with the MF, the RF had a beneficial
effect regarding uremic crises and mortality rate
in dogs with mild and moderate renal failure. Dogs
fed the RF had a slower decline in renal function,
compared with dogs fed the MF.
Conclusions and Clinical Relevance—Dietary
modifications are beneficial in minimizing extrarenal
manifestations of uremia and mortality rate in dogs
with mild and moderate spontaneous chronic renal
failure. Results are consistent with the hypothesis
that delay in development of uremic crises and associated
mortality rate in dogs fed RF was associated,
at least in part, with reduction in rate of progression
of renal failure. (J Am Vet Med Assoc 2002;220: