A Case of Urinary Bladder Malakoplakia in a Young French Bulldog: Diagnostic and Therapeutic Issues.

A 3-month-old female French Bulldog presented with hematuria, severe pollakiuria, and urinary incontinence lasting for 1.5 months. Broad-spectrum empirical antibiotic therapy and nonsteroidal anti-inflammatory drugs were initiated by the referring veterinarian. Due to a lack of improvement, the dog was referred. At referral examination, urinary clinical signs persisted (hematuria, severe pollakiuria) and a firm bladder was noted. Abdominal ultrasonography revealed severe, diffuse bladder wall thickening with a significant reduction in the bladder lumen. Urinary tract endoscopy showed whitish exophytic proliferations throughout the entire bladder wall. Histological bladder wall analysis led to a diagnosis of bladder malakoplakia. Prolonged antibiotic therapy with fluoroquinolones was prescribed and resulted in clinical remission despite persistent bacteria in the bladder wall. This report describes a case of successfully medically managed bladder malakoplakia, a very rare condition in veterinary medicine, well documented in humans.

Eosinophilic Inflammation and Equine Herpesvirus-1 Associated With Haemorrhagic Cystitis in a Horse. Case Report.

Equine idiopathic haemorrhagic cystitis (EIHC) is a recently described form of aseptic cystitis in horses in which there is no discernible underlying cause. This case report describes a 9-year-old Thoroughbred gelding that presented with stranguria, pollakiuria, and haematuria. Cystoscopy revealed ulceration and haemorrhage of the bladder mucosa, diffuse mural hyperaemia and marked urine sedimentation. Histopathological evaluation of the bladder revealed chronic active ulcerative neutrophilic, lymphoplasmacytic, and eosinophilic cystitis. There was no bacterial or fungal growth upon culture but polymerase chain reaction (PCR) testing and sequencing for equine herpesvirus-1 (EHV-1) on bladder mucosa was positive. Conservative therapy with broad spectrum antimicrobials and non-steroidal anti-inflammatory therapy yielded complete resolution of clinical signs with significant improvement of macroscopic lesions in 14 days. Although a positive EHV-1 PCR suggests a viral cause, the horse's clinical signs, histology and recovery rate are more consistent with equine idiopathic haemorrhagic cystitis (EIHC). Neutrophilic and lymphoplasmacytic inflammation is a known feature of EIHC but eosinophilic infiltrates have not been previously described. The significance of the eosinophilic involvement is not certain; however, their presence has been associated with fungal, viral, parasitic, and immune-mediated aetiologies in other body systems. This is the first report of a horse with possible EIHC in Australia, as well as the first case with eosinophilic infiltrates and testing positive for EHV-1.

Exertional hemolysis and hematuria in a Labrador Retriever dog.

A 7-y-old male Labrador Retriever dog was presented because of acute onset of dark-colored urine after a hunting session the day prior. Moderate hemoglobinemia was observed, associated with transient hemoglobinuria and hematuria with no concurrent evidence of underlying urinary tract disease. The patient's clinical signs resolved within 36 h post-exercise without specific treatment. The concurrent occurrence of exertional hemolysis and hematuria in a dog is uncommon; these conditions are commonly reported separately in human athletes.

Ultrasonographic and contrast-enhanced CT imaging diagnosis of idiopathic renal hematuria with bilateral hydronephrosis and hydroureter in a dog.

A 5-year-old spayed female Maltese presented with a 1-week history of severe hematuria. Abdominal ultrasonography and thoracic, and abdominal computed tomography identified bilateral hydronephrosis and hydroureter due to an obstruction at the left ureter and urinary bladder lesion with no evidence of metastasis. After surgical removal of the material and placement of a temporary ureteral stent, the patient was able to urinate normally. Histological examination revealed a massive blood clot. Based on our review of the literature, this is the first published report describing the imaging diagnosis of obstructive hydronephrosis and hydroureter induced by idiopathic renal hematuria in a dog.

Leiomyosarcoma of urinary bladder in a Shih Tzu dog.

A 10-year-old intact male Shih Tzu dog presented with hematuria. Double-contrast cystography revealed a polypoid filling defect at the apex of the urinary bladder. Ultrasonography revealed a heterogeneously hypoechoic intramural mass with minimal vascular flow beneath the submucosal layer. After partial cystectomy, a well-demarcated bladder leiomyosarcoma was diagnosed on histopathology. The patient was alive and well without any clinical signs, recurrence, or metastasis at the 29-month follow-up after the surgical removal of the bladder mass. Leiomyosarcoma should be considered as a differential diagnosis if mass-like lesions are observed in the urinary bladder, although this type of malignancy is rare in canines. Histopathological confirmation is important for predicting prognosis and determining further medical plans.

Discolored Urine in Horses and Foals.

This article describes the most common causes of urine discoloration. The review includes a description of the most common disorders causing hematuria, highlighting clinical presentation, treatments, and pathophysiology. Causes of hemoglobinuria and myoglobinuria together with their mechanisms of renal injury are also reviewed.

Imaging of the Urinary Tract.

This article provides a comprehensive review of imaging techniques used to evaluate the equine urinary tract. This overview includes officially recognized modalities and new applications reported in the most current literature. Technical aspects and indications for use of endoscopy and ultrasonography are highlighted. Normal endoscopic and ultrasonographic appearance of the upper and lower urinary tract is described, with characterization of common abnormalities found in patients with hematuria, stranguria, and renal failure. Visual examples of several pathologic conditions from clinical cases are provided. An outline of the main features, potentials, and limitations of radiography, nuclear scintigraphy, and computed tomography is provided.

Metastatic urothelial carcinoma of the urinary bladder in a Sumatran tiger (Panthera tigris sondaica).

A 15-year-old spayed female Sumatran tiger (Panthera tigris sondaica) was presented with a short history of haematuria and dysuria, non-responsive to antibiotics, and a gradual decline to inappetence over a period of 2-3 months. Ultrasound examination showed a thickened urinary bladder wall and the renal pelvis of right kidney was dilated and cystic. A presumptive diagnosis of renal failure was made, and the tigress was euthanised due to deteriorating quality of life and pronounced weight loss. Histopathology revealed extensive erosion of the urinary bladder wall and marked congestion of the submucosal vasculature, a potential cause of the haematuria observed clinically. Numerous foci of neoplastic cells were also observed throughout the lung parenchyma as well as within lymphatic vessels of the lung, the liver and the kidney. A diagnosis of a metastatic non-papillary high-grade urothelial carcinoma (UC) of the urinary bladder was made. Consistent with this diagnosis, immunohistochemistry revealed the neoplastic cells were negative for uroplakin III, as has been reported for a subset of high-grade, infiltrative urinary bladder UCs of canines and humans. This is the first report of a primary tumour of the urinary bladder in a tiger and the first report of UC in a tiger.

Bladder wall adhesion causing a vesicular septum in a dog following surgical cystotomy.

CASE DESCRIPTION: An 8-year-old spayed female Yorkshire Terrier-Poodle dog was evaluated for persistent pollakiuria and stranguria following routine cystotomy for calcium oxalate cystoliths. CLINICAL FINDINGS: The dog presented for a cystotomy with intermittent hematuria. Postoperative radiographs revealed no remaining cystoliths. Urine, cystolith, and bladder mucosal aerobic cultures were negative. Pollakiuria, stranguria, and hematuria developed immediately after surgery and persisted despite antibiotics. Ultrasound revealed suspected fibrous adhesions within the urinary bladder lumen connecting the dorsal and ventral bladder wall creating a septum. This was confirmed cystoscopically 4 weeks after surgery. TREATMENT AND OUTCOME: Cystoscopic-guided laser ablation was performed to incise abnormal tissue connecting the ventral and dorsal bladder wall using a holmium:yttrium-aluminum-garnet laser. Three weeks later, ultrasound revealed adhesion resolution though mild pollakiuria and stranguria persisted. Oxybutynin was prescribed and clinical signs resolved. At 27 months after ablation, hematuria occurred with recurrent cystoliths. These cystoliths were removed by percutaneous cystolithotomy, documenting a cystoscopically normal bladder wall. The patient had normal urination for 55.5 months after ablation, with normal bladder wall thickness on ultrasound repeated at 27 and 36 months after ablation. CLINICAL RELEVANCE: To the authors' knowledge, an adhesion creating a septum between the dorsal and ventral bladder wall has not been previously reported as a complication after cystotomy in any species and should be considered as a cause of persistent lower urinary signs after surgery. Ultrasound identified the lesion in this dog. Because bladder abnormalities can develop quickly after surgery, ultrasound might be considered if urine testing is not supportive of infection. Cystoscopic-guided laser ablation was a successful minimally invasive treatment in this case.

Effect of urine-specific gravity on performance of bacteriuria in predicting urine culture results.

OBJECTIVE: To determine the effect of urine-specific gravity (USG) on using microscopic evaluation of bacteriuria to predict urine culture results in dogs and cats. MATERIALS AND METHODS: We performed a retrospective medical record review of canine and feline patients that had a urinalysis and urine culture performed simultaneously. The sensitivity, specificity, positive predictive value and negative predictive value of microscopic bacteriuria for predicting urine culture results were calculated, stratified by USG. Multivariable regression was performed to test the effect of USG, pyuria, haematuria and species on the agreement between microscopic bacteriuria and culture results. RESULTS: A total of 481 dogs and 291 cats with paired urinalysis and urine culture results were included in the study. Microscopic bacteriuria had moderate sensitivity (76% in dogs, 64% in cats) and high specificity (97% in dogs, 96% in cats) for predicting urine culture bacterial growth. Samples with rod bacteria were more likely to have bacterial growth than those with cocci (OR=Infinity, 95% CI 4.8 - Infinity). As compared to isosthenuric+hyposthenuric samples (USG ≤1.012), agreement was lower in moderately concentrated (OR=0.44, 95% CI 0.19 to 0.91) samples. Absence of bacteriuria, pyuria and haematuria had a high negative predictive value for no bacterial growth (96%). CLINICAL SIGNIFICANCE: Microscopic bacteriuria has a high specificity in predicting urine culture results, regardless of USG. The finding that microscopic bacteriuria has better agreement with urine culture results in isosthenuric+hyposthenuric urine argues against reflex culture in these samples, especially if pyuria and haematuria are also absent. Urine microscopy can aid clinicians in determining the likelihood of urine culture growth.

Hematuria in a 3-month-old filly with an internal umbilical abscess and internal iliac artery aneurysm.

A 3-month-old foal with a history of acute hematuria was evaluated. Hydronephrosis and hydroureter were visualized upon renal ultrasonography of the left kidney. Cystoscopy identified a blood clot occluding the left ureter. Computed tomography (CT) revealed a large retroperitoneal abscess at the level of the aortic bifurcation and a left internal iliac aneurysm. Due to the severity of the lesions and the poor prognosis, the filly was euthanized and the clinical findings were confirmed by post-mortem examination. This report emphasizes the value of obtaining a precise diagnosis via CT in order to avoid unviable treatment approaches when confronted with this unusual secondary complication of omphaloarteritis. Key clinical message: Umbilical complications are routinely diagnosed in equine neonatal medicine, and commonly lead to septicemia, physitis, and septic arthritis; severe internal umbilical abscessation, and subsequent vascular and urinary disorders are uncommon sequelae.

Hématurie chez une pouliche de 3 mois avec abcès ombilical interne et anévrisme de l'artère iliaque interne. Un poulain de 3 mois ayant des antécédents d'hématurie aiguë a été évalué. L'hydronéphrose et l'hydro-uretère ont été visualisés par échographie rénale du rein gauche. La cystoscopie a identifié un caillot sanguin obstruant l'uretère gauche. La tomodensitométrie (TDM) a révélé un gros abcès rétropéritonéal au niveau de la bifurcation aortique et un anévrisme iliaque interne gauche. En raison de la gravité des lésions et du mauvais pronostic, la pouliche a été euthanasiée et les résultats cliniques ont été confirmés par un examen post-mortem. Ce rapport souligne l'intérêt d'obtenir un diagnostic précis par TDM afin d'éviter des approches thérapeutiques non-viables face à cette complication secondaire inhabituelle de l'omphalo-artérite.Message clinique clé :Les complications ombilicales sont couramment diagnostiquées en néonatalogie équine et conduisent généralement à une septicémie, une épiphysite et une arthrite septique; un abcès ombilical interne sévère et des troubles vasculaires et urinaires subséquents sont des séquelles peu fréquentes.(Traduit par Dr Serge Messier).

Hematúria macroscópica em equinos associada à infecção por Leptospira interrogans / Macroscopic haematuria in horses associated with Leptospira interrogans infection

Hematúria é uma grave manifestação clínica de doença do sistema urinário, ocorrendo sob as formas micro ou macroscópica. Neste artigo relatam-se dois casos de hematúria macroscópica associada à infecção por Leptospira interrogans sorogrupo Canicola. O exame clínico inicial revelou hematúria macroscópica, taquicardia, taquipneia, febre, elevação do tempo de perfusão capilar, hipomotilidade intestinal, além de icterícia da mucosa oral. Leucocitose, proteinúria, glicosúria, piúria e azotemia foram achados comuns aos dois casos. Teste de Soroaglutinação Microscópica foi realizado para titulação de anticorpos contra Leptospira interrogans. Tratamento incluiu medidas terapêuticas de suporte (fluidoterapia), controle da hematúria e antibioticoterapia. Sete dias após manifestação dos sinais clínicos iniciais, ambos animais receberam alta hospitalar após remissão dos sinais clínicos.

Haematuria is a serious clinical manifestation of urinary system disease, occurring in micro or macroscopic forms. In this article two cases of macroscopic haematuria associated with Leptospira interrogans serogroup Canicolainfection are related. The initial clinical examination revealed macroscopic haematuria, tachycardia, tachypnea, fever, increased capillary perfusion time, intestinal hypomotility, in addition to jaundice of the oral mucosa. Leukocytosis, proteinuria, glycosuria, pyuria and azotemia were common findings in both cases. Microscopic serum agglutination test was performed for titration of antibodies against Leptospira interrogans. Treatment included supportive therapeutic measures (fluid therapy), hematuria control and antibiotic therapy. Seven days after the manifestation of the initial clinical signs, both animals were discharged from the hospital without complications.

Clinical findings and outcome following medical treatment in dogs with idiopathic renal haematuria: 41 cases (2001-2018).

OBJECTIVES: To characterise and document the progression of idiopathic renal haematuria in a large cohort of medically managed UK dogs. MATERIALS AND METHODS: Retrospective study of 41 client-owned dogs with confirmed (n=14), or suspected (n=27) idiopathic renal haematuria from 4 UK-based referral centres. Clinical findings and outcomes of dogs (2001 to 2018) were determined from the review of medical records and telephone follow-up. RESULTS: Median survival time from diagnosis was long [1482 (152 to 1825) days] irrespective of treatment and clinical response. Only 1 case was euthanased due to idiopathic renal haematuria, and anaemia or azotaemia occurred infrequently. In total, 25 dogs received angiotensin-converting enzyme-inhibitor or angiotensin receptor blocker therapy, of which 23 received benazepril [0.44 (0.19 to 0.82) mg/kg/24 hours], two received enalapril (0.40 and 0.78 mg/kg/24 hours) and one received telmisartan (1 mg/kg/24 hours). In cases with follow-up urinalyses, complete resolution of haematuria was documented in eight of 19 (42%) dogs following angiotensin-converting enzyme-inhibitor/angiotensin receptor blocker treatment, with partial improvement in five of 19 (26%) and no improvement in six of 19 (31%). Conversely, of the two untreated dogs where outcome was available, one had partial improvement and the other had no improvement. CLINICAL SIGNIFICANCE: In this study, idiopathic renal haematuria was associated with a good prognosis and low complication rate. Resolution or improvement in haematuria occurred in both angiotensin-converting enzyme-inhibitor/angiotensin receptor blocker-treated and untreated dogs, indicating that further studies are required to evaluate the effectiveness and safety of these interventions.

Successful Management of Urinary Bladder Clot with Intravesical Tissue Plasminogen Activator Infusion in a Cat.

A 5 yr old male neutered domestic shorthair with intermittent signs of urinary tract obstruction was suspected of having a blood clot in the urinary bladder secondary to trauma. The cat was hospitalized and received standard supportive therapy for urinary tract obstruction with urinary catheterization, with the addition of intravesical saline flushes in an attempt to promote bladder clot lysis. The cat was subsequently discharged after voluntary urination was observed. The cat was represented 28 hr after discharge because of clinical signs consistent with urinary tract obstruction. The cat was hospitalized and intravesical tissue plasminogen activator (tPA) infusions (0.5 mg of tPA in 10 mL of saline with 2 hr dwell time q 8 hr) were administered to break down the bladder clot (2.78 × 4.46 cm). Thirty-two hours after starting tPA, the clot was no longer visible on ultrasound. The cat was discharged with no recurrent symptoms in the subsequent 11 mo. This is the first report of tPA being used for dissolution of bladder clot in a cat. There were no observed complications, suggesting that intravesical instillation of tPA may be a safe and efficacious therapy in cats, similar to the previously reported successes in dogs and humans.

Desempenho de diferentes marcas de tiras reagentes relativo à densidade e à análise química da urina de cães e gatos / Performance of different brands of reagent strips for density and chemical analysis of dog and cat urine

Objetivou-se verificar a compatibilidade entre diferentes marcas de tiras reagentes para urinálise, tanto de uso veterinário, como de uso humano, e confrontar os parâmetros semiquantitativos desse instrumento com métodos quantitativos. Para isso, foram analisadas 77 amostras frescas de urina de cães e gatos e testados 04 modelos de tiras reagentes. Quanto à densidade urinária, houve correlação razoável entre os métodos quantitativo e semiquantitativo naquelas amostras com pH ácido, mas não naquelas com pH neutro ou alcalino. Quanto à concentração proteica, houve similaridade de 53,3% a 83,3% entre as marcas testadas e quando comparadas com a análise fotométrica houve uma correlação razoável (rs = 0,69752 a 0,75074). Em ponto de corte de 15mg/dL de proteína, a sensibilidade da tira reagente foi 82,5% e 100% para urina canina e felina, respectivamente. No tocante à hematúria, houve divergência razoável entre a sedimentoscopia e as diferentes marcas de tiras reativas. Quanto à piúria, há uma baixa sensibilidade das tiras em relação às amostras caninas com muitos resultados falso-negativos (33% a 75%), enquanto em amostras felinas a sensibilidade foi de 100%. Assim, independente da marca, as tiras reagentes devem servir apenas como teste rápido de triagem, sendo mais apropriado o uso de métodos quantitativos na avaliação clínica do paciente a partir da urinálise.

The aim was to verify the compatibility between different brands of urinary dipsticks, for both human and veterinary use, and to compare the semiquantitative parameters of this instrument with quantitative methods. For this, 77 fresh samples of urine from dogs and cats were analyzed e and 04 models of reagent strips were tested. Regarding urinary density, a reasonable correlation was observed between the quantitative and semiquantitative methods in those samples with acidic pH, which did not occur in those with neutral or alkaline pH. Regarding the protein concentration, there was similarity from 53.3% to 83.3% between the brands and in the comparative analysis between the control strip and the photometric analysis, there was a reasonable correlation (rs = 0.69752 to 0.75074). In cut-off point of 15mg/dL protein, the sensitivity of the reagent strip was 82.5% and 100% for canine and feline urine, respectively. Regarding hematuria, there was a reasonable divergence of results between sedimentation and tested dipsticks. As for pyuria, there is a low sensitivity of the strips in relation to canine samples with many false negative results (33% to 75%), while in feline samples the sensitivity was 100%. Thus, regardless of the brands, the reagent strips should serve only as a rapid screening test, while the use of quantitative methods in the clinical evaluation of the patient from urinalysis is more appropriate.

Use of contrast-enhanced ultrasound for the diagnosis of idiopathic renal hematuria in a dog.

Background: Idiopathic renal hematuria (IRH) generally occurs in healthy large-breed dogs that are <2-years-old. It is characterized by recurrent bleeding from the kidneys of unidentified cause. The final diagnosis is reached through the exclusion of primary urinary system and systemic causes of hematuria along with the direct visualization by cystoscopy of hematic urine jets at the ureteral orifice. Case Description: An 8-year-old female neutered Whippet was presented for investigation of a 4-week history of chronic intermittent macroscopic hematuria. Physical examination, systolic blood pressure, extensive laboratory workup (including coagulation profile and platelet count), urine culture, thoracic and abdominal radiographs, pneumocystogram, and double-contrast cystography were all unremarkable. B-mode ultrasound showed no abnormalities apart from a moderate amount of suspended echogenic amorphous material visible within the urinary bladder lumen. In the contrast-enhanced ultrasound (CEUS) study, a large amount of echogenic ill-defined material was noted projecting into the urinary bladder lumen from the right ureterovesical junction in the fundamental mode. This material was more conspicuous and markedly contrast-enhancing in the harmonic mode. Ultrasound contrast medium has the unique property to strictly remain within the vessels without interstitial trapping or elimination by the kidneys. Indeed, the presence of the micro-bubbles into the urinary tract lumen in the CEUS study was interpreted as a direct sign of active urinary tract bleeding. A diagnosis of IRH was reached through CEUS and B-mode ultrasound along with an extensive laboratory workup and periodic follow-up of the patient. No therapy was administered and at a 1-year follow-up, the patient was alive with no current episodes of macroscopic hematuria reported. Conclusion: To the authors' knowledge, this is the first report describing the use of CEUS for the characterization of IRH. CEUS could represent a safe, non-invasive, affordable novel alternative technique to cystoscopy or cystotomy for the real-time diagnosis of IRH.

Suspected anaphylactic shock associated with administration of tranexamic acid in a dog.

A 10-year-old male castrated Maltese was referred with clinical signs of hematuria, stranguria, and pollakiuria. The dog was diagnosed with sterile hemorrhagic cystitis with urethroliths and cystoliths. To remove the uroliths, the dog underwent retrograde urohydropropulsion followed by a cystotomy. The following day, persistent bleeding in the urinary bladder was identified with large hematoma, hematuria and anemia. In order to reduce bleeding, the dog received 10 mg/kg of tranexamic acid (TXA) intravenously. Immediately after TXA administration, the dog developed anaphylactic shock manifested by hypotension, hypothermia, tachycardia and a dull mentation. Thus, an emergency treatment including bolus injection of crystalloid, administration of dexamethasone and diphenhydramine, and oxygen supplementation was given, after which the dog quickly recovered within a few minutes.

Use of cystoscopy or cystourethroscopy in treating benign macroscopic hematuria caused by lower urinary tract hemorrhage in three dogs.

CASE DESCRIPTION: A 5-year-old 11.5-kg (25.3-lb) castrated male Boston Terrier (dog 1), an 8-year-old 27.8-kg (61.2-lb) castrated male Boxer (dog 2), and a 10.5-year-old 15.9-kg (35.0-lb) spayed female Pembroke Welsh Corgi (dog 3) were evaluated because of severe, gross hematuria and suspected idiopathic renal hematuria. CLINICAL FINDINGS: All 3 dogs had hematuria, anemia, blood clots in their urinary bladders, and unremarkable findings on coagulation and mucosal bleeding time assessments. With cystourethroscopy, lower urinary tract hemorrhage originating from a small lesion in the urinary bladder (n = 2) or urethra (1) and normal-appearing yellow urine jetting from both ureterovesicular junctions were visualized in each dog. TREATMENT AND OUTCOME: Cystoscopically guided surgical resection of a hemorrhagic lesion of the urinary bladder was performed on dog 1, and histologic evaluation of the resected tissue confirmed urinary bladder telangiectasia. Dogs 2 and 3 each underwent cystourethroscopically guided laser ablation of a hemorrhagic lesion (presumptively diagnosed as hemangioma, angioma, or telangiectasia) in the urinary bladder (dog 2) or urethra (dog 3). The longest follow-up duration was 7 years, and none of the 3 dogs had subsequent recurrence of gross hematuria. CLINICAL RELEVANCE: Findings suggested that cystourethroscopy should be considered part of the diagnostic plan for hematuria in dogs before pursuing major surgical treatment or when results of conventional diagnostic procedures do not indicate the underlying cause. In addition, histologic results for dog 1 indicated urinary bladder telangiectasia, previously an unreported cause of severe, chronic lower urinary tract hematuria in dogs.

Equine Idiopathic Hemorrhagic Cystitis: Is It Idiopathic or More Likely to Be Exercise-Associated?

Recently, a syndrome called "equine idiopathic hemorrhagic cystitis" was described and clinical features compared with bladder neoplasia. In this case report, we describe a case of hemorrhagic cystitis with a favorable outcome in a high-performance dressage horse, in which exercise intensity might be the etiologic factor for the development of bladder-wall hyperplasia and hematuria. A 14-year-old Warmblood gelding was presented with a history of hematuria of 2-day duration. The high-level dressage horse had performed on the previous 3 weekends and was trained at least three times a week at performance intensity level. Sonographically, the dorsal bladder wall was about 1.5 cm thick and the different layers of the bladder wall could not be differentiated. Endoscopy revealed that the bladder was highly edematous and showed diffuse submucosal bleeding. Histopathological differential diagnoses were severe reactive hyperplasia or a low-grade transitional cell carcinoma. Four months later, bladder wall thickness had decreased to 1.0 cm and the different layers of the bladder wall were easily visible sonographically. Endoscopy showed a normal bladder mucosa. On histopathology, hyperplasia of the epithelium was significantly decreased. A diet low in calcium was recommended after the checkup, and the owners started working the horse very lightly for 2 days a week. Over the following 2 months, hematuria had not recurred. In conclusion, it seems likely that hemorrhagic cystitis in this horse was exercise-associated, but as repeated provocation by high exercise intensity was not performed in this case, this remains an assumption.