Oral glucosamine and the management of feline idiopathic cystitis

Survey of veterinarians in the USA to evaluate trends in the treatment approach for non-obstructive feline idiopathic cystitis

OBJECTIVES

The goal of this study was to gather information on treatment approaches and trends for the treatment of non-obstructive feline idiopathic cystitis (FIC).

METHODS

An internet-based survey of veterinarians was conducted focusing on outpatient treatment approaches for cats that are stable, not obstructed and that exhibit lower urinary signs suspected to be due to FIC, where other causes (eg, urolithiasis, urinary tract infection, other) have been ruled out.

RESULTS

A total of 606 veterinarians submitted complete surveys for inclusion. Respondents reported that when obtaining patient histories, in ⩾75% of client interactions they gathered information about feline stressors (542/606, 89%), resource set-up (eg, number of litter boxes; 466/606, 77%) and diet (552/606, 91%). Only 31% (187/606) of respondents reported that they gathered information about daily human/cat interaction in ⩾75% of client interactions, with 69% (419/606) of veterinarians inquiring about this information 50% of the time or less. Top treatments selected for acute presentations of FIC were analgesics (537/606, 89%), modified litter box management (435/606, 72%) and synthetic feline pheromones (422/606, 70%). Top treatments selected for chronic FIC management were prescription diets (519/606, 86%), modified litter box management (508/606, 84%) and environmental enhancements (493/606, 81%). Challenges with owner compliance and expectations were selected as barriers to achieving a positive treatment outcome by 81% (486/599) and 62% (372/599) of respondents, respectively. Rehoming or euthanasia were recommended by 37% (224/606) and 10% (59/606) of veterinarians, respectively, due to difficulties managing FIC.

CONCLUSIONS AND RELEVANCE

The treatment approach for non-obstructive FIC appears to be multimodal and recommendations vary between acute and chronic presentations. An area of opportunity is client communication and education, which may improve owner compliance and help set appropriate expectations. The importance of human/cat interaction as a management strategy appears under-emphasized.

Uroprotective and pain-relieving effect of dietary supplementation with micronized palmitoyl-glucosamine and hesperidin in a chronic model of cyclophosphamide-induced cystitis

Introduction

Feline idiopathic cystitis is a common, chronic-relapsing disorder of the lower urinary tract. In addition to environmental modification/enrichment, long-term and safe treatment targeting specific pathophysiological changes may be of help. In this context, effective dietary interventions hold clinical promise. Palmitoyl-glucosamine (PGA) and hesperidin (HSP) are safe and authorized feed ingredients for animal nutrition under European regulations.

Methods

The current study aimed to investigate whether a 3:1 mixture of micronized PGA and HSP could represent a novel mechanism-oriented approach to chronic cystitis management. A newly validated rat model of cyclophosphamide (CYP)-induced chronic cystitis was used (40 mg/kg, three intraperitoneal injections every 3rd day). Animals were randomized to orally receive either vehicle or PGA-HSP at a low (72 + 24 mg/kg) or high (doubled) dose for 13 days, starting 3 days before the chronic CYP protocol, with mesna (2-mercaptoethane-sulfonate) being used as a reference drug.

Results

Higher PGA-HSP dose was effective at relieving chronic visceral pain, as measured by mechanical allodynia test (von Frey test). The severity of cystitis was also significantly improved, as shown by the reduced sonographic thickening of the bladder wall, as well as the decrease in edema, bleeding and bladder to body weight ratio compared to the vehicle treated group. A significant decrease of MPO activity, MDA level and fibrosis at Masson's trichrome staining was also observed in animals administered PGA-HSP in comparison to vehicle treated ones. The CYP-induced increase in bladder mRNA expression of pro-inflammatory cytokines was also significantly counteracted by the study mixture. Moreover, CYP-induced bladder mast cell accumulation and releasability were significantly decreased by PGA-HSP (even at the low dose), as determined by metachromatic staining, chymase and tryptase immunostaining as well as enzyme-linked immunosorbent assay for histamine and 5-hydoxytriptamine.

Discussion

PGA-HSP is able to block CYP-induced decrease of tight junction proteins, claudin-1 and occludin, thus preserving the urothelial bladder function. Finally, neuroinflammatory changes were investigated, showing that dietary supplementation with PGA-HSP prevented the activation of neurons and non-neuronal cells (i.e., microglia, astrocytes and mast cells) at the spinal level, and counteracted CYP-induced increase of spinal mRNA encoding for pro-inflammatory cytokines. Altogether, the present findings confirm the uroprotective and pain-relieving effect of PGA-HSP and pave the way to potential and relevant clinical applications of the study supplement in feline idiopathic cystitis.

Incidence of feline idiopathic cystitis and urethral obstruction during COVID-19 human movement restrictions in Queensland, Australia

OBJECTIVES

Feline idiopathic cystitis (FIC) and urethral obstruction (UO) are commonly linked to increased stress. The influence of human movement restrictions on their incidence remains undetermined. FIC with or without UO is associated with environmental stress factors. The severe acute respiratory syndrome coronavirus 2 (COVID-19) pandemic restricted human movement and working behaviours. It is unknown if these restrictions increased the risk of FIC or UO in cats.

METHODS

Total cat emergency accessions and transfers between 8 February 2019 and 8 February 2021 at two private hospitals were retrospectively reviewed. Cats were included in the FIC group if they presented with lower urinary tract signs and supporting urinalysis, and were included in the UO group if they presented with UO. Cats with current urinary tract infection, or previous FIC or UO, were excluded. Groups were considered 'pre-COVID-19' between February 2019 and 2020 and 'COVID-19' between February 2020 and 2021. Cases of FIC and UO were compared between COVID-19 and pre-COVID-19 using Fisher's exact test and relative risk (RR) calculations.

RESULTS

The pre-COVID-19 incidence of FIC was 4.3% (63/1477, 95% confidence interval [CI] 0.0332-0.053), non-obstructive FIC was 1.4% (20/1477, 95% CI 0.008-0.020) and UO was 2.9% (43/1477, 95% CI 0.020-0.038). One cat was excluded as obstruction occurred during hospitalisation. The COVID-19 incidence of FIC was 5.4% (113/2081, 95% CI 0.044-0.64), non-obstructive FIC was 2.1% (70/2081, 95% CI 0.014-0.027) and UO was 3.4% (70/2081, 95% CI 0.026-0.042). The risk of non-obstructive FIC (P = 0.122; RR 0.652, 95% CI 0.387-1.096), UO (P = 0.382; RR 0.839, 95% CI 0.577-1.22) or either (P = 0.098; RR 0.773, 95% CI 0.572-1.044) was not significantly higher in the COVID-19 period than the pre-COVID-19 period.

CONCLUSIONS AND RELEVANCE

No clear association between COVID-19 movement restrictions and the incidence of UO or non-obstructive FIC was found within this retrospective population.

Diagnostic effectiveness of stress biomarkers in cats with feline interstitial and bacterial cystitis

BACKGROUND

Although bacterial cystitis (BC) and feline interstitial cystitis (FIC) are categorized under feline lower urinary tract disease (FLUTD) due to their similar clinical manifestations, stress is an important factor for FIC. Therefore, the investigation of stress biomarkers might be important in the differentiation and elucidation of these conditions.

OBJECTIVES

We aimed to evaluate the diagnostic effectiveness of serum and urine cortisol, serotonin, and dopamine concentrations and their relationship with stress in cats with FIC and BC.

METHODS

Twelve healthy cats (Control group) and 24 cats with FLUTD were used. The cats with FLUTD were divided into FIC and BC groups.

RESULTS

Multimodal environmental modification (MEMO) scores were found to be higher in the FIC group than in the BC and Control groups (P < .001). Urine serotonin concentrations were higher in cats with FIC and BC compared with those in the Control group. Based on ROC analyses, the sensitivity, specificity, and accuracy of urine serotonin and dopamine were found to be statistically significant in being able to differentially diagnose cats in the FIC group vs the Control group. The sensitivity, specificity, and accuracy of serum dopamine were also found to be statistically significant for the differential diagnosis of FIC and BC.

CONCLUSIONS

High urine serotonin concentrations were found in cats with FLUTD compared with healthy controls and interpreted as the presence of stress not only in cats with FIC but also in cats with BC. Also, based on the ROC-based diagnostic performance evaluation of these stress biomarkers, urine serotonin, and dopamine concentrations can be used to diagnose FIC, and serum dopamine concentrations can be used to differentiate FIC and BC in cats.

Prevalence, Risk Factors, Pathophysiology, Potential Biomarkers and Management of Feline Idiopathic Cystitis: An Update Review

Feline idiopathic cystitis is a widespread disease in small animal clinics, which mainly presents with urinary signs like dysuria, stranguria, hematuria, pollakiuria, and periuria. The etiopathogenesis of the disease may involve interactions between the environmental stressors, neuroendocrine system and bladder of affected cats. Diagnostic biomarkers have not been tested in clinical studies though they are theoretically feasible, and since the clinical signs of the disease assemble those of other feline lower urinary diseases, its diagnosis is a procedure of exclusion. The primary treatment of the disease is long-term multimodal environmental modification (or enrichment) while anti-anxiety drugs and nutritional supplements are recommended for chronic recurrent cases. Still, many medicines need to be evaluated for their efficacy and safety. This review aims to provide readers with a comprehensive understanding of feline idiopathic cystitis by summarizing and updating studies concerning the prevalence, risk factors, etiological hypotheses, diagnostic procedures, possible treatments, and prognosis of the disease.

Commercial vs Homemade Cat Diets: What you need to know

PRACTICAL RELEVANCE

A feeding plan recommendation for cats, both healthy and with disease, should include diet choice, amounts to feed and the feeding method. Diet choice can be complex owing to the abundance of products, sometimes with conflicting marketing messages, and the prevalence of information with no scientific basis. It is important to be aware of the specific challenges of both commercial and homemade diets. Moreover, a nutritional assessment is a prerequisite when recommending a diet to ensure that it is safe, appropriate for the cat's life stage and nutritious for long-term feeding.

COMMERCIAL VS HOMEMADE DIETS

There are a variety of commercial diets available, allowing considerable customisation. These products are regulated and can be tested to determine nutritional adequacy and safety, although as the industry is partly self-regulated, choice of manufacturer is important. Properly formulated homemade diets can be customised to the patient and are a good option when no commercial product that meets the patient's needs exists. Homemade diets can be an owner preference. A serious limitation is the lack of testing, potentially affecting safety and also resulting in a reliance on database information to determine nutritional adequacy. Generic homemade diet recipes (eg, sourced from the internet) have additional risks of deficiencies and imbalances, and are not recommended. Homemade diets should be devised by a veterinary nutrition specialist with consideration of both patient and owner factors.

CLINICAL CHALLENGES

Dietary misinformation, which is all too readily available on the internet, may result in owners making questionable feeding choices for their pets. A homemade diet may be requested by owners based on the perception that there are poor ingredients in commercial foods. The veterinary healthcare team needs to have good evidence-based information to present to owners about diet choice.

EVIDENCE BASE

Several decades of research on feline nutrition forms the basis for nutritional requirements and dietary recommendations. There are varying degrees of evidence regarding requirements for each nutrient, and a lack of data on the effects of different types of processing on nutrient needs.

Retrospective interview-based long-term follow-up study of cats diagnosed with idiopathic cystitis in 2003-2009

OBJECTIVES

The aim of this study was to register long-term recurrence rates and mortality rates in cats diagnosed with feline idiopathic cystitis (FIC), with an observation period until death or a minimum of 10 years.

METHODS

Data regarding recurrence of signs of feline lower urinary tract disease (FLUTD) and FLUTD-related mortality in cats diagnosed with FIC between 2003 and 2009 were obtained through structured telephone interviews with the cat owners from December 2018 until February 2019. The interviews were based on a standardised questionnaire covering whether the cat was still alive or not, whether death/euthanasia were due to FLUTD and whether the cat had experienced recurrent episodes of clinical signs of FLUTD. If recurrences had occurred, exact numbers or estimates of 1-3, 4-6 or >6 recurrences were recorded.

RESULTS

The owners of 50/105 FIC cats included in a previous study (48%) were available for inclusion in the present study. At the time of the interview, only 6/50 cats (12%) were still alive. The FLUTD-related mortality rate was 20% (n = 10/50). Twenty-three cats (46%) had no recurrences, three cats (6%) were euthanased shortly after diagnosis, nine cats (18%) had 1-3 recurrences, three cats (6%) had 4-6 recurrences and six cats (12%) had >6 recurrences. For the remaining six cats, the number of recurrences was uncertain.

CONCLUSIONS AND RELEVANCE

The long-term prognosis for cats diagnosed with FIC may, based on the results from the present study, be regarded as fairly good, as approximately 70% of the cats either recovered without additional episodes, experienced only a few recurrences, are still alive after a minimum of 10 years since inclusion in the study, or were euthanased for reasons unrelated to FLUTD.

The effect of a therapeutic urinary stress diet on the short-term recurrence of feline idiopathic cystitis

The aim of this cohort study was to evaluate the effect of a therapeutic urinary stress diet on recurrent clinical signs of lower urinary tract disease in cats with idiopathic cystitis. The effects of feeding a therapeutic urinary stress diet were compared with feeding a non-therapeutic diet for a duration of 5 weeks. The owners selected themselves which food to feed their cat. Of 31 cats with acute non-obstructive idiopathic cystitis, 17 were fed the test food and 14 the control food. An episode of recurrence was defined as a minimum of one day with at least two clinical signs; i.e. stranguria, periuria, haematuria, dysuria and pollakiuria. The number of cats fed the therapeutic urinary stress diet that had an episode of recurrence (5/17) was significantly lower compared with cats that were fed other commercial diets (11/14). The formulation of the foods fed to the participating cats (dry, moist or a combination of both) was not found significant compared with the recurrence of idiopathic cystitis. Apart from type of diet, no other risk factors affected the short-term recurrence of FIC. A prospective clinical trial is needed to confirm these findings.

A prospective randomized study of efficacy of 2 treatment protocols in preventing recurrence of clinical signs in 51 male cats with obstructive idiopathic cystitis

Background

Urethral obstruction (UO) is a common complication of feline idiopathic cystitis (FIC). Robust treatment recommendations to prevent its recurrence are scarce.

Objectives

To evaluate meloxicam treatment for prevention of clinical recrudescence in male cats with obstructive FIC.

Animals

Fifty‐one client‐owned cats.

Methods

Prospective, randomized clinical trial. Every male cat with FIC‐associated UO was deemed eligible for the study and was recruited during hospitalization. After discharge, cats were treated with phenoxybenzamine and alprazolam for 2 weeks, with (24 cats) or without (27 cats) low‐dose meloxicam (0.025 mg/kg/day PO) and monitored for 6 months.

Results

Cumulative number (%) of cats with recurrent UO at 10 days, 1‐, 2‐, and 6‐months after discharge was 1 (2%), 2 (4%), 4 (8%), and 8 (16%), respectively. Overall, 12 (24%) cats experienced signs of recurrent FIC within 6 months, with (8 cats) or without (4 cats) concurrent UO. No difference in the cumulative incidence of UO within 6 months was detected with addition of meloxicam (odds ratio [95% confidence interval], 0.63 [0.13‐2.97]; P = .70). All cats were alive at 6 months.

Conclusions and Clinical Importance

No clinical benefit was detected with the addition of low‐dose meloxicam to phenoxybenzamine and alprazolam treatment for 2 weeks after discharge. Nevertheless, this study was underpowered to identify potential differences, and its findings must be corroborated in larger studies.

A closer look at the health of cats showing urinary house-soiling (periuria): a case-control study

OBJECTIVES

The aim of this study was to perform a case-control medical evaluation of cats from multi-cat households presenting with inappropriate latrining and spraying behavior.

METHODS

Owners of 18 'spraying' and 23 'latrining' cats with normal control subjects available from the same households were recruited for a case-control study. Otherwise overtly healthy dyads (each dyad consisting of a case cat and a control cat) were brought together to the veterinary hospital of the University of São Paulo for a medical work-up (ie, physical examination, complete blood count, biochemical profile, urinalysis and urine culture, abdominal ultrasound of the urinary system and in females, where possible, cystoscopy).

RESULTS

Medical problems were identified with similar frequency in the 'sprayers' (38.9%), 'latriners' (39.1%) and controls of the latrining group (26.1%), but not the controls of the spraying group (5.5%). The difference between 'cases' and 'controls' from spraying households was significant. Common potential health-related changes include renal insufficiency, cystitis and bladder lithiasis. Renal calculi, higher creatinine levels (within normal reference interval) and 'glomerulations' (detected during cystoscopy) were also found in the remaining sprayers and latriners that were considered clinically healthy. Post-cystoscopy, a new form of periuria occurred in two cats (one sprayer and one latriner).

CONCLUSIONS AND RELEVANCE

These results indicate that spraying or latrining behavior in the home, as well as living with a cat that is not using the litter box as a latrine, are all associated with a higher level of urinary tract abnormalities; living with a cat that is spraying, however, does not have this association. The findings also suggest that both forms of periuria might be associated with interstitial cystitis. We therefore conclude that all cats with periuria need to be carefully evaluated medically and that treatment of latrine-related problems should consider all cats in the house, whereas spraying may be more focused on the individual displaying the problem.

Quantified water intake in laboratory cats from still, free-falling and circulating water bowls, and its effects on selected urinary parameters

OBJECTIVES

The study objectives were to determine if the method of water presentation (still [S], circulating [C] or free-falling [FF] bowl systems) influences daily water consumption in cats in a controlled environment, and whether differences in water intake affect urine relative super saturation (RSS) for calcium oxalate and struvite, urine specific gravity (USG), urine osmolality (Uosmol) and urine volume.

METHODS

Sixteen healthy laboratory cats fed a dry diet were individually housed with urine collection systems. Each cat underwent a randomized 2 week crossover period with all bowl systems, allowing a 1 week acclimation period between each crossover. Water intake was measured daily by bowl weight, accounting for spillage and evaporation. USG and urine volume were measured daily, whereas other urinary parameters were measured at various time points throughout each 14 day crossover period.

RESULTS

Fourteen cats completed the study. Average daily water intake (ml/kg/day), urine volume, USG and urine RSS for struvite and calcium oxalate were not significantly different between water bowls. Uosmol was significantly higher in C compared with S and FF bowl systems (P = 0.009 for both). Three individual cats demonstrated a significant water bowl preference (Cat 4: C >S, P = 0.039; Cat 10: FF >C, P = 0.005; Cat 11: S >C, P = 0.037).

CONCLUSIONS AND RELEVANCE

Overall, water bowl type had no appreciable effect on water intake. Uosmol was the only urinary parameter found to be significantly different, and was higher for the C bowl. The implication of this is unknown, considering water intake did not differ significantly between bowls. Alternative methods to increase water intake should be implemented beyond providing unique water bowls in patients where augmented water intake would be beneficial for disease management.

Recurrence rate and long-term course of cats with feline lower urinary tract disease

OBJECTIVES

Feline lower urinary tract disease (FLUTD) causes clinical signs such as stranguria, pollakiuria, haematuria, vocalisation and periuria, and is often associated with recurring episodes. The primary objective of this study was to survey the long-term course of cats presenting with FLUTD in terms of recurrence rate and mortality.

METHODS

Data from cats that were presented with lower urinary tract signs from 2010 to 2013 were collected by telephone interview with cat owners, using a questionnaire. The observation period ranged from the first presentation due to FLUTD to the telephone interview or the cat's death. Data on diagnoses, recurrence of clinical signs and disease-free intervals, as well as implementation and impact of prophylactic measures (PMs), were collected and compared between groups with different aetiologies.

RESULTS

The study included 101 cats. Fifty-two cats were diagnosed with feline idiopathic cystitis, 21 with urolithiasis and 13 with bacterial urinary tract infection; 15 had no definitive diagnosis. Of the 86 cats with a known diagnosis, the recurrence rate was 58.1%, with no significant difference between groups. Twenty-one cats had one relapse, 12 had two relapses, 10 had three and seven had four to eight relapses within a median observation period of 38 months (range 0.5-138 months). Fourteen cats suffered from different causes of FLUTD at different episodes. Mortality due to FLUTD among all 101 cats was 5.0%. The recurrence rate in cats with urolithiasis receiving at least two PMs was significantly lower than the recurrence rate in those without PMs (P = 0.029).

CONCLUSIONS AND RELEVANCE

More than half of the cats with FLUTD presented with two or more recurrent episodes irrespective of the identified aetiology. Cats should be thoroughly investigated at each presentation as it cannot be presumed that the cause of FLUTD is the same at different episodes. The mortality due to FLUTD is lower than previously reported.

Evaluation of three herbal compounds used for the management of lower urinary tract disease in healthy cats: a pilot study

OBJECTIVES

Lower urinary tract disease (LUTD) occurs commonly in cats, and idiopathic cystitis (FIC) and urolithiasis account for >80% of cases in cats <10 years of age. Although several strategies have been recommended, a common recommendation is to induce dilute urine resulting in more frequent urination and to dilute calculogenic constituents. In addition to conventional therapy using modified diets, traditional Chinese and Western herbs have been recommended, although only one - choreito - has published data available. We evaluated three commonly used herbal treatments recommended for use in cats with LUTD: San Ren Tang, Wei Ling Tang and Alisma. We hypothesized that these three Chinese herbal preparations would induce increased urine volume, decreased urine saturation for calcium oxalate and struvite, and differences in mineral and electrolyte excretions in healthy cats.

METHODS

Six healthy spayed female adult cats were evaluated in a placebo-controlled, randomized, crossover design study. Cats were randomized to one of four treatments, including placebo, San Ren Tang, Wei Ling Tang or Alisma. Treatment was for 2 weeks each with a 1 week washout period between treatments. At the end of each treatment period, a 24 h urine sample was collected using modified litter boxes.

RESULTS

Body weights were not different between treatments. No differences were found in 24 h urinary analyte excretions, urine volume, urine pH or urinary saturation for calcium oxalate or struvite between treatments.

CONCLUSIONS AND RELEVANCE

The results of this study do not support the hypothesis; however, evaluation of longer-term and different dosage studies in cats with LUTD is warranted.

Caregiver placebo effect in analgesic clinical trials for cats with naturally occurring degenerative joint disease-associated pain

A literature review identified six placebo-controlled studies of analgesics in client-owned cats with degenerative joint disease-associated pain. Five studies with 96 cats had available data. Caregiver responses on a clinical metrology instrument, Client-Specific Outcome Measure (CSOM), were compared to measured activity. Cats were categorised as 'successes' or 'failures' based on change in CSOM score and activity counts from baseline. Effect sizes based on CSOM score were calculated; factors that were associated with success/failure were analysed using logistic regression. Effect sizes ranged from 0.97 to 1.93. The caregiver placebo effect was high, with 54-74 per cent of placebo-treated cats classified as CSOM successes compared with 10-63 per cent of cats classified as successes based on objectively measured activity. 36 per cent of CSOM successes were also activity successes, while 19 per cent of CSOM failures were activity successes. No significant effects of cat age, weight, baseline activity, radiographic score, orthopaedic pain score or study type on CSOM success in the placebo groups were found. The caregiver placebo effect across these clinical trials was remarkably high, making demonstration of efficacy for an analgesic above a placebo difficult. Further work is needed to determine whether a potential placebo-by-proxy effect could benefit cats in clinical settings.

Comparison of foods with differing nutritional profiles for long-term management of acute nonobstructive idiopathic cystitis in cats

OBJECTIVE

To evaluate the effect of nutrition on recurrent clinical signs of lower urinary tract (LUT) disease in cats with idiopathic cystitis.

DESIGN

Randomized, controlled, masked clinical trial.

ANIMALS

31 cats with acute nonobstructive idiopathic cystitis.

PROCEDURES

Cats were assigned to receive 1 of 2 foods (a cystitis prevention or control food) that differed in mineral (calcium, phosphorous, and magnesium), antioxidant, and fatty acid profiles. Owners documented LUT signs daily for up to 1 year. The primary endpoint was the number of recurrent episodes in which a cat had multiple (≥ 2 concurrent) LUT signs within a day (defined as multiple-sign day). Consecutive days in which a cat had multiple LUT signs were considered as a single episode.

RESULTS

4 cats fed prevention food and 2 cats fed control food were excluded from analysis because of noncompliance, gastrointestinal signs, food refusal, or owner voluntary withdrawal. The proportion of cats fed prevention food that had ≥ 1 recurrent episode of multiple-sign days (4/11) was not significantly lower than that of cats fed control food (9/14). However, cats fed prevention food had significantly lower mean incidence rates for recurrent episodes of multiple-sign days (0.7 episodes/1,000 cat-days) and episodes of hematuria (0.3 episodes/1,000 cat-days), dysuria (0.2 episodes/1,000 cat-days), and stranguria (0.2 episodes/1,000 cat-days) as single LUT signs, compared with cats fed control food (5.4, 3.4, 3.1, and 3.8 episodes/1,000 cat-days, respectively). Significantly fewer cats fed prevention food required analgesics (4/11), compared with cats fed control food (12/14).

CONCLUSIONS AND CLINICAL RELEVANCE

Foods with differing nutritional profiles appeared to impact mean incidence rates of recurrent feline idiopathic cystitis-associated signs.

Efficacy of intravesical pentosan polysulfate sodium in cats with obstructive feline idiopathic cystitis

OBJECTIVES

Obstructive feline idiopathic cystitis is a common emergency in small animal practice. There is evidence for a defective glycosaminoglycan layer in the urinary bladder of affected cats. The aim of this study was to investigate the effect of intravesical pentosan polysulfate sodium (PPS) in cats with obstructive feline idiopathic cystitis in a randomised, placebo-controlled, blinded clinical study.

METHODS

Thirty-five cats with obstructive feline idiopathic cystitis were enrolled into the study. On day 0, cats were randomised to receive either 30 mg PPS in saline (18 cats) or saline alone as placebo (17 cats) at the time of indwelling urinary catheter placement and then after 24 and 48 h. The catheter was clamped for 30 mins after administration before connecting it to a sterile urine collection system. The procedure was repeated after 24 and 48 h, and then the indwelling catheter was removed. Treatment success was assessed via the incidence of recurrent urethral obstruction, results of a scoring system for physical examination and daily urinalysis from day 0 to 5.

RESULTS

Recurrent urethral obstruction occurred in 3/18 cats of the verum group and 3/17 of the placebo group (P = 1.000). The verum group showed a significantly lower degree of microscopic haematuria between day 5 and day 0 (P ⩽0.05). The placebo group showed a significantly lower degree of dipstick haematuria between day 5 and day 0 (P ⩽0.05). There was no difference in the clinical score between the groups in the investigated time period.

CONCLUSIONS AND RELEVANCE

Intravesical instillation of PPS three times within 48 h in the chosen dose had no influence on the incidence of recurrent urethral obstruction and clinical signs in cats with obstructive feline idiopathic cystitis.

AAFP and ISFM Guidelines for diagnosing and solving house-soiling behavior in cats

RATIONALE

These Guidelines have been developed by the American Association of Feline Practitioners (AAFP) and the International Society of Feline Medicine (ISFM) as a resource for veterinary practitioners who want to better understand and manage the important clinical condition of house-soiling in their feline patients. The Guidelines offer straightforward, practical solutions that, in most cases, will help veterinarians and cat owners prevent, manage or entirely remediate feline house-soiling behavior.

EVIDENCE BASE

The Guidelines include scientifically documented information when it is available. However, because research is often lacking, some recommendations reflect the accumulated clinical experience of the authors.

Intravesical application of lidocaine and sodium bicarbonate in the treatment of obstructive idiopathic lower urinary tract disease in cats

BACKGROUND

In human patients with interstitial cystitis, intravesical instillation of alkalinized lidocaine sometimes is associated with sustained amelioration of symptoms beyond the acute treatment phase. Interstitial cystitis shares many features in common with feline idiopathic cystitis.

OBJECTIVE

To evaluate whether intravesical instillation of alkalinized lidocaine decreases recurrence of urethral obstruction and severity of clinical signs in cats with obstructive idiopathic LUTD.

ANIMALS

Twenty-six cats with obstructive idiopathic LUTD. Twelve cats in case group (treatment with alkalinized lidocaine) and 14 control cats (treatment with placebo or standard treatment).

METHODS

Cats were randomly assigned to treatment (2 or 4 mg/kg lidocaine and sodium bicarbonate) or placebo groups (0.2 mL/kg saline solution and sodium bicarbonate). The intravesical instillation was done once a day for 3 days. Some cats underwent standard treatment only (indwelling urinary catheter for 3 days without intravesical instillations). A 2-week, 1-month, and 2-month follow-up after treatment was made using a questionnaire. The recurrence rate and amelioration scores of clinical signs were assessed and compared.

RESULTS

Recurrence of urethral obstruction was 58% (7/12) in the case group and 57% (8/14) in the control group. Amelioration scores were similar between the 2 groups.

CONCLUSION AND CLINICAL IMPORTANCE

Intravesical administration of lidocaine for up to 3 consecutive days had no apparent beneficial effect on decreasing recurrence rate and severity of clinical signs in cats with obstructive idiopathic LUTD.

Effects of oral administration of N-acetyl-d-glucosamine on plasma and urine concentrations of glycosaminoglycans in cats with idiopathic cystitis

OBJECTIVE

To determine the effects of once-daily oral administration of N-acetyl-d-glucosamine (NAG) on plasma and urine glycosaminoglycan (GAG) concentrations in cats with idiopathic cystitis (IC).

ANIMALS

19 cats with IC and 10 clinically normal cats.

PROCEDURES

Cats with IC were randomly assigned to receive 250 mg of NAG in capsule form orally once daily for 28 days (n = 12) or a placebo (capsule containing cellulose) orally once daily for the same period (7). In cats with IC, plasma and urine GAG concentrations and urine creatinine concentration were measured on days 0 (immediately before first dose), 7, 14, 21, 28, and 56. For purposes of comparison, those variables were measured in 10 clinically normal cats on day 0.

RESULTS

Mean ± SEM urine GAG-to-creatinine concentration ratios (day 0 data) for cats with IC and clinically normal cats differed significantly (3.11 ± 0.62 μg/mL and 14.23 ± 3.47 μg/mL, respectively). For cats with IC, mean plasma GAG concentration in NAG-treated cats (39.96 ± 5.34 μg/mL) was higher than that in placebo-treated cats (24.20 ± 3.35 μg/mL) on day 21. In the NAG-treated cats, plasma GAG concentration on days 21 (39.96 ± 5.34 μg/mL) and 28 (39.91 ± 6.74 μg/mL) differed significantly from the day 0 concentration (27.46 ± 3.90μg/mL).

CONCLUSIONS AND CLINICAL RELEVANCE

Cats with IC have lower urinary GAG-to-creatinine concentration ratios than did clinically normal cats. Administration of NAG (250 mg, PO, q 24 h) significantly increased plasma GAG concentrations in cats with IC after 21 days of treatment.

Idiopathic cystitis in domestic cats--beyond the lower urinary tract

Signs of lower urinary tract (LUT) disease in domestic cats can be acute or chronic, and can result from variable combinations of abnormalities within the lumen of the LUT, the parenchyma of the LUT itself, or other organ system(s) that then lead to LUT dysfunction. In the majority of cats with chronic signs of LUT dysfunction, no specific underlying cause can be confirmed after standard clinical evaluation of the LUT, so these cats typically are classified as having idiopathic cystitis. A syndrome in human beings commonly known as interstitial cystitis (IC) shares many features in common with these cats, permitting comparisons between the two species. A wide range of similarities in abnormalities has been identified between these syndromes outside as well as inside the LUT. A variety of potential familial and developmental risk factors also have been identified. These results have permitted generation of the hypothesis that some of these people have a disorder affecting the LUT rather than a disorder of the LUT. This perspective has suggested alternative diagnostic strategies and novel approaches to treatment, at least in cats. The purpose of this review is to summarize research investigations into the various abnormalities present in cats, to compare some of these findings with those identified in human beings, and to discuss how they might modify perceptions about the etiopathogenesis, diagnosis, and treatment of cats with this disease. Dedication: I dedicate this contribution to Professor Dennis J. Chew, whose collaboration, patience, and support made it all possible.

Influence of nutrition on feline calcium oxalate urolithiasis with emphasis on endogenous oxalate synthesis

The prevalence of calcium oxalate (CaOx) uroliths detected in cats with lower urinary tract disease has shown a sharp increase over the last decades with a concomitant reciprocal decrease in the occurrence of struvite (magnesium ammonium phosphate) uroliths. CaOx stone-preventative diets are available nowadays, but seem to be marginally effective, as CaOx urolith recurrence occurs in patients fed these diets. In order to improve the preventative measures against CaOx urolithiasis, it is important to understand its aetiopathogenesis. The main research focus in CaOx formation in cats has been on the role of Ca, whereas little research effort has been directed towards the role and origin of urinary oxalates. As in man, the exogenous origin of urinary oxalates in cats is thought to be of minor importance, although the precise contribution of dietary oxalates remains unclear. The generally accepted dietary risk factors for CaOx urolithiasis in cats are discussed and a model for the biosynthetic pathways of oxalate in feline liver is provided. Alanine:glyoxylate aminotransferase 1 (AGT1) in endogenous oxalate metabolism is a liver-specific enzyme targeted in the mitochondria in cats, and allows for efficient conversion of glyoxylate to glycine when fed a carnivorous diet. The low peroxisomal activity of AGT1 in cat liver is compatible with the view that felids utilised a low-carbohydrate diet throughout evolution. Future research should focus on understanding de novo biosynthesis of oxalate in cats and their adaptation(s) in oxalate metabolism, and on dietary oxalate intake and absorption by cats.

Comparison of digital and optical hand-held refractometers for the measurement of feline urine specific gravity

Measuring urine specific gravity (USG) is an important component of urine analysis as it evaluates renal concentrating capability. The objective of this study was to quantify the difference in USG values between a hand-held optical analogue refractometer and a cat-specific digital instrument. Urine samples from 55 cats were assessed. There was a statistically significant difference between these two refractometers (P<0.001), with the optical refractometer (mean USG=1.031) consistently reading higher than the digital refractometer (mean USG=1.027). Results for a random subset of the samples (n=10) were compared with urine osmolality and both the optical and digital instruments demonstrated excellent correlation. While an accurate USG reading is important, it is unlikely that the statistical significance between the two instruments is clinically significant and, therefore, unlikely to result in a change in patient evaluation or treatment plans. While both the digital and optimal refractometers are highly correlated to the urine osmolality, making both devices valid for assessment of USG in clinical practice, this digital device is easier to read and eliminates the variability of subjective interpretation.

Use of pentosan polysulphate in cats with idiopathic, non-obstructive lower urinary tract disease: a double-blind, randomised, placebo-controlled trial

Idiopathic feline lower urinary tract disease (FLUTD) is a common clinical entity where different treatments, for example glycosaminoglycans (GAGs) such as pentosan polysulphate (PPS), are advocated. However, few treatments have been investigated by well-controlled clinical trials. This paper compares the use of PPS in FLUTD compared to placebo. Of the 18 cats in the experiment, nine were treated with PPS and nine were treated with placebo with subcutaneous injections of 3mg/kg PPS or placebo day 1, 2, 5 and 10. The study was double-blind, randomised and placebo-controlled. Revaluation was performed after 5 and 10 days, 2 weeks, 2, 6 and 12 months. There were no statistically significant differences concerning clinical signs between groups during treatment or at re-evaluation, except for pretreatment stressful events where PPS-treated cats had experienced significantly more stressful events compared to cats treated with placebo before entering the study. Six cats (33%) showed recurrence of clinical signs during the entire study period, and only one of these cats had more than one recurrent episode. One cat (placebo) was euthanased 7 days after initial treatment because of recurrence of clinical signs. Another cat (placebo) was euthanased due to other reasons after 6 months. At 2 weeks two cats (placebo and PPS) showed clinical signs. At 2 months re-evaluation one cat showed mild clinical signs. At 6 and 12 months all remaining 16 cats were healthy. Idiopathic, non-obstructive FLUTD is a self-limiting disease with good short-term and excellent long-term prognosis without treatment. Whether or not PPS may be beneficial in a subpopulation of cats with continuous or frequently recurring clinical signs may be elucidated in forthcoming double-blind, randomised and placebo-controlled trials including only this subpopulation of cats.

Guarded long-term prognosis in male cats with urethral obstruction

The aim of this study was to evaluate the course of urethral obstruction in cats. Forty-five male cats with urethral obstruction or lower urinary tract signs referable to urethral obstruction were included in the study. Follow-up information was gained by telephone interview in most cases and was available in 39 cats. Of the 22 cats with idiopathic urethral obstruction, eight (36%) re-obstructed after 3-728 days (median 17 days). Of 10 cats with urolithiasis, three (30%) re-obstructed after 10, 13 and 472 days, respectively. Of the seven cats with urethral plugs, three (43%) re-obstructed after 4, 34 and 211 days, respectively. Recurrent signs of lower urinary tract disease including obstruction were common in cats with urethral obstruction (20/39; 51%) and occurred in the same frequency irrespective of the primary cause of the obstruction. Recurrent obstruction (14/39; 36%) was the most common reason for euthanasia and was performed in 8/39 (21%) cats.

Evidence-Based Management of Feline Lower Urinary Tract Disease

Many treatments have been recommended for managing cats with feline urinary tract disease (FLUTD). Veterinarians making therapeutic decisions should consider the quality of evidence supporting a recommendation to use (or not use) a particular treatment for cats with FLUTD. Whenever possible, recommendations should be based on results of randomized and well-controlled scientific studies performed in clinical patients with the spontaneously occurring disease of interest. In the absence of such studies, one is left to make the best recommendation possible with consideration of all information, including the quality of the evidence. At this time, additional studies are needed to evaluate evidence for many currently recommended treatments for cats with FLUTD.

Nutrition and lower urinary tract disease in cats

Lower urinary tract disease occurs commonly in cats and is often associated with crystal-related disease. Dietary modification is beneficial in managing some of these diseases, including idiopathic cystitis, urolithiasis, and urethral matrix-crystalline plugs. Altering dietary formulation may result in decreasing urinary concentrations of crystallogenic compounds, increasing urinary concentrations fo crystallogenic inhibitors, and diluting urine composition.

Clinical evaluation of multimodal environmental modification (MEMO) in the management of cats with idiopathic cystitis

This prospective observational study evaluated client-reported recurrence of lower urinary tract signs (LUTS) and other signs of abnormalities in cats with idiopathic cystitis after institution of multimodal environmental modification (MEMO). Forty-six client-owned indoor-housed cats with idiopathic cystitis, diagnosed based on a history of recurrent LUTS and evidence of absence of urolithiasis or bacterial urinary tract infection were studied. In addition to their usual care, clients were offered recommendations for MEMO based on a detailed environmental history. Cases were followed for 10 months by client contact to determine the effect of MEMO on LUTS and other signs. Significant (P<0.05) reductions in LUTS, fearfulness, nervousness, signs referable to the respiratory tract, and a trend (P<0.1) toward reduced aggressive behavior and signs referable to the lower intestinal tract were identified. These results suggest that MEMO is a promising adjunctive therapy for indoor-housed cats with LUTS, and should be followed up with prospective controlled clinical trials.