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Background Commercially available, noninvasive testing options for histoplasmosis are limited outside of the United States. Objectives To describe the diagnostic performance of a novel Histoplasma antigen enzyme immunoassay (IM EIA) for the diagnosis of histoplasmosis in dogs. Animals Twenty dogs with histoplasmosis, 79 dogs without histoplasmosis, and 11 unclassified dogs providing 202 urine samples. Methods This a prospective study using stored urine samples. Samples were analyzed with the IM EIA and with the commercially available Histoplasma antigen EIA (MV EIA). Dogs were classified based on final proven diagnosis and performance of the IM EIA was described and compared with the MiraVista enzyme immunoassay (MV EIA). Results The diagnostic sensitivity (DSe), specificity (DSp), and accuracy (DAc) of the IM EIA were 70% (51%-89%), 99% (97%-100%), and 93% (81%-100%), respectively. The DSe, DSp, and DAc for the MV EIA were 95% (85%-100%), 99% (97%-100%), and 98% (95%-100%), respectively. The area under the receiver operator characteristic curve was significantly smaller for IM EIA (0.87) as compared with MV EIA (0.97, P = .03). This was primarily due to 6 false negative IM EIA results, 4 from dogs with disease localized to the gastrointestinal tract. The MV EIA was positive in 5/6 of these dogs. Conclusions and clinical importance The IM EIA might be useful for the diagnosis of disseminated histoplasmosis in dogs, but clinical usefulness will be limited in dogs with histoplasmosis localized to the GI tract.

The need for consortial programs to provide advanced education in food animal veterinary production medicine has been recognized and lauded for nearly three decades. This article describes one effort to create a dairy production medicine curriculum funded by a United States Department of Agriculture (USDA) Higher Education Challenge Grant. This National Center of Excellence in Dairy Production Medicine Education for Veterinarians is housed at the Dairy Education Center of the University of Minnesota and the project was a collaboration of the University of Minnesota, the University of Illinois, the University of Georgia, and Kansas State University. The article reviews the need for innovative ways to educate students who will optimally serve the dairy industry, provides a broad overview of the process of developing and delivering the eight-week dairy production medicine curriculum, and describes the challenges faced and lessons learned as a result of offering such a program.

INTRODUCTION AND OBJECTIVE:As with clinical urodynamics, investigations into lower urinary tract physiology using animal models require catheter-based systems to measure bladder pressure while fill...

Transurethral and suprapubic catheterization have both been used to test urethral function in rats; however, it is unknown whether these methods affect urethral function or if the order of catheterization affects the results. The aim of this cross-over designed experiment was to compare the effects of catheterization methods and order on leak point pressure (LPP) testing. LPP and simultaneous external urethral sphincter electromyography (EUS EMG) were recorded in anesthetized female virgin Sprague-Dawley rats in a cross-over design to test the effects of transurethral and suprapubic catheterization. There was no significant difference in peak bladder pressure during LPP testing whether measured with a transurethral or suprapubic catheter. There was no significant difference in peak bladder pressure between the first and second catheter insertions. However, peak EMG firing rate, as well as peak EMG amplitude and EMG amplitude difference between peak and baseline were significantly higher after the first catheter insertion compared to the second insertion, regardless of the catheter method. Our results suggest that route of catheterization does not alter urethral function, e.g. create a functional partial outlet obstruction. Either catheterization method could be used for LPP and/or EUS EMG testing in rats.

Stress urinary incontinence (SUI) is more prevalent among women who deliver vaginally than women who have had a cesarean section, suggesting that tissue repair after vaginal delivery is insufficient. A single dose of mesenchymal stem cells (MSCs) has been shown to partially restore urethral function in a model of SUI. The aim of the present study was to determine if increasing the number of doses of MSCs improves urethral and pudendal nerve function and anatomy. We hypothesized that increasing the number of MSC doses would accelerate recovery from SUI compared with vehicle treatment. Rats underwent pudendal nerve crush and vaginal distension or a sham injury and were treated intravenously with vehicle or one, two, or three doses of 2 × 106 MSCs at 1 h, 7 days, and 14 days after injury. Urethral leak point pressure testing with simultaneous external urethral sphincter electromyography and pudendal nerve electroneurography were performed 21 days after injury, and the urethrovaginal complex and pudendal nerve were harvested for semiquantitative morphometry of the external urethral sphincter, urethral elastin, and pudendal nerve. Two and three doses of MSCs significantly improved peak pressure; however, a single dose of MSCs did not. Single, as well as repeated, MSC doses improved urethral integrity by restoring urethral connective tissue composition and neuromuscular structures. MSC treatment improved elastogenesis, prevented disruption of the external urethral sphincter, and enhanced pudendal nerve morphology. These results suggest that MSC therapy for postpartum incontinence and SUI can be enhanced with multiple doses.

The diagnosis of coccidioidomycosis (CM) in dogs is typically based on clinical presentation, serology, and (less frequently) spherule identification. Agar gel immunodiffusion (AGID) is the most commonly employed serological method, but AGID is slow (requiring up to a week for titer). A Coccidioides antigen enzyme immunoassay (EIA) is also available; however, sensitivity is low in CM dogs. An antibody EIA was developed to detect canine immunoglobulin G (IgG) reacting to Coccidioides antigens. Serum was evaluated from dogs with pathology proven CM and/or AGID positive CM, as well as dogs with histoplasmosis, blastomycosis, non-fungal infections, or healthy dogs. A standard curve was used to convert optical density (OD) values into EIA units (EU). Serum and urine samples from CM dogs were also tested in the antigen EIA. Sensitivity and specificity for IgG were 89.2% and 97.2%, respectively, upon evaluation of dogs with proven or probable CM and control dogs. Cross-reactivity was observed in 7.7% and in 6.4% of dogs with histoplasmosis or blastomycosis, respectively. The antigen EIA alone was insensitive (33.8%). Combined IgG and antigen testing increased sensitivity to 93.2%, as three dogs were IgG-negative but had detectable serum or urine antigen. In 22 dogs with proven CM, sensitivity was statistically similar for antibody EIA and AGID (86% and 73%; P = .487). The MiraVista® canine Coccidioides antibody IgG EIA may aid in the diagnosis of CM by improving turnaround time with comparable sensitivity to AGID. Serial or concurrent testing by antibody and antigen EIAs may be beneficial when screening dogs for CM.

Background An in-house Histoplasma urine antigen test for cats might be desirable in certain situations. Objective To validate and compare the diagnostic performance of a monoclonal antibody-based IMMY urine Histoplasma antigen enzyme immunoassay (IMMY EIA) to the commercially available urine Histoplasma antigen enzyme immunoassay (MiraVista Diagnostics, MV EIA). Animals One hundred ninety-three urine samples from 105 client-owned and purpose-bred research cats. Methods Cats were classified as Histoplasma positive or negative based on diagnostic investigation. The IMMY EIA and MV EIA were performed on all urine samples. Correlation and agreement between the assays were determined. Diagnostic performance was determined and compared between assays. Results The IMMY EIA, with a 0.25 ng/mL diagnostic cutoff, provided a diagnostic sensitivity (DSe), diagnostic specificity (DSp), and diagnostic accuracy (DAc) of 89% (95% confidence interval [CI]; 73%-97%), 80% (67%-89%), and 83% (74%-90%), respectively. The IMMY EIA, with a 1.1 ng/mL diagnostic cutoff, provided a DSe, DSp, and DAc of 77% (95% CI 60%-90%), 97% (88%-100%), and 89% (81%-95%), respectively. The MV EIA provided a DSe, DSp, and DAc of 94% (95% CI 81%-99%), 97% (89%-100%), and 96% (90%-99%), respectively. Moderate overall agreement was found between MV EIA and IMMY EIA using the 0.25 ng/mL cut-off (к = 0.44; 95% CI 0.31-0.57) and the 1.1 ng/mL cut-off (к = 0.43, 95% CI, 0.31-0.56). Conclusions and clinical importance The IMMY EIA might be useful as a diagnostic test for histoplasmosis in cats. Further modifications of the IMMY EIA are required to achieve the diagnostic performance of the MV EIA.

Objectives The aim of this study was to describe clinical and diagnostic findings in cats with bone and joint disease associated with histoplasmosis. Methods Medical records from between 2011 and 2017 were reviewed. Inclusion criteria required: (1) diagnosis of histoplasmosis by cytology, histology, urine or serum Histoplasma antigen testing, or culture; and (2) lameness or joint effusion as a presenting complaint or physical examination finding. Results Twenty-five cases met the inclusion criteria. Four had incomplete records, but available data were included when applicable. Lameness was a presenting complaint in 17/21 cats and was the only complaint in 9/21 cats. Initial diagnosis was made by cytology in 22/25 cats and by culture, urine antigen and necropsy in one case each. Diagnostic cytology samples included synovial fluid (n = 13), lymph node (n = 5), skin (n = 2), lung (n = 1) and bone (n = 1). Two additional cases had synovial fluid examined but no organisms present. Inflammation was present in all synovial fluid samples examined. Biopsy was obtained in two cats and histologic diagnoses included osteomyelitis with no infectious organisms identified and severe lymphoplasmacytic synovitis suggestive of feline periosteal proliferative polyarthritis. Histoplasma urine antigen test was positive in 7/12 cats. Conclusions and relevance Inflammatory arthritis is common in cats with histoplasmosis, with lameness a common presenting complaint. Organisms are found in synovial fluid cytology in most cases. If not, appropriate additional diagnostics must be pursued.

Case summary This report describes a cat with a rare form of histoplasmosis: invasive rhinitis with adnexal involvement, mimicking disease more commonly caused by cryptococcosis or aspergillosis. This case is especially noteworthy as it was from an area where histoplasmosis is not enzootic. Relevance and novel information Invasive fungal rhinitis causes significant morbidity in cats. Diagnostic investigation of more common pathogens includes detection of fungal antigen ( Cryptococcus) or antifungal antibodies ( Aspergillus). This case demonstrates that histoplasmosis can present as chronic nasal disease in cats. Histoplasma antigen testing provides a non-invasive diagnostic option. Moreover, this case serves as a reminder that histoplasmosis can affect cats anywhere, even in non-enzootic areas.

Introduction To investigate the pharmacokinetics and pharmacodynamics of oral pimobendan in conscious, healthy cats. Animals Eight healthy adult cats. Materials and methods A randomised, single-blinded, crossover design was used. Two oral doses of pimobendan (0.625-mg [LD], 1.25-mg [HD]) and a control substance (3-mL water) were administered to each cat. Blood collection, echocardiography, and oscillometric blood pressure measurements were performed repeatedly for 12 h following each dose. Plasma concentrations of pimobendan and the active metabolite, O-desmethylpimobendan (ODMP), were quantified using ultra-high-performance liquid chromatography tandem mass spectrometry. Cardiovascular parameters were evaluated for between- and within-treatment effects over time using linear mixed modelling. Results Pimobendan was rapidly absorbed and converted to ODMP with the pimobendan AUC0–∞ greater than ODMP AUC0–∞ (ODMP:pimobendan AUC0–∞ ratio 0.6 [LD] and 0.5 [HD]) despite a longer elimination half-life of ODMP (pimobendan t1/2 0.8 h vs. ODMP t1/2 1.6 h [LD]; pimobendan t1/2 0.7 h vs. ODMP t1/2 1.3 h [HD]). Averaged across all time points, pimobendan increased several measures of systolic function; however, its effect could not be further characterised. Although treatment was well-tolerated, two cats vomited following HD and another had a ventricular premature beat recorded following LD. Conclusions The lower ODMP:pimobendan AUC0–∞ ratio compared to that observed previously in dogs suggests reduced metabolism in cats. Treatment effects were observed in measures of systolic function; however, the duration of action and differences in effects between the two pimobendan doses could not be characterised. Further studies are required to evaluate pimobendan in feline cardiovascular medicine.

This is a procedure for a sham control chronic cat experiment (Day 0) for cystotomy (bladder surgery). The cystotomy is performed without UroMOCA implantation. The cat is observed daily and imaged on day 0, 14 and 30 to track changes to the bladder and overall cat health in response to the cystotomy. This protocol includes basic surgery, urodynamics and imaging for Day 0 in the chronic experiments.

This is a procedure for a sham control chronic implant cat experiment (Day 30-terminal) for cystotomy (bladder surgery). The cystotomy was performed and an inactive UroMOCA was implanted on Day 0. The cat was observed daily and imaged on day 0, 14 and 30 to track changes to the bladder and overall cat health in response to the cystotomy and device implant. This protocol includes , urodynamics and imaging for Day 30 in the chronic experiments.

This protocol for cat surgery to expose the badder for inactive device insertion.

This protocol for cat surgery to expose the badder for inactive device insertion.

INTRODUCTION AND OBJECTIVE:In research animal models, catheterization for cystometry requires anesthesia which affects neuro-urological pathways, or animal restraint, limiting measurement time and ...

INTRODUCTION AND OBJECTIVE:Stress urinary incontinence (SUI) in women results from injuries to muscles, nerves, and ligaments sustained during childbirth compounded by aging. Pelvic floor electrica...

This multi-institutional study was designed to determine the clinical pharmacokinetics of fluconazole and outcomes in client-owned dogs (n = 37) and cats (n = 35) with fungal disease. Fluconazole serum concentrations were measured. Pharmacokinetic analysis was limited to animals at steady state (≥72 hr of treatment). The mean (range) body weight in 31 dogs was 25.6 (2.8-58.2) kg and in 31 cats was 3.9 (2.4-6.1) kg included in pharmacokinetic analyses. The dose, average steady-state serum concentrations (CSS ), and oral clearance in dogs were 14.2 (4.5-21.3) mg/kg/d, 26.8 (3.8-61.5) µg/mL, and 0.63 ml min-1 kg-1 , respectively, and in cats were 18.6 (8.2-40.0) mg/kg/d, 32.1 (1.9-103.5) µg/mL, and 0.61 ml min-1 kg-1 , respectively. Random inter-animal pharmacokinetic variability was high in both species. Two dogs had near twofold increases in serum fluconazole when generic formulations were changed, suggesting lack of bioequivalence. Median CSS for dogs and cats achieving clinical remission was 19.4 and 35.8 µg/ml, respectively. Starting oral doses of 10 mg/kg q12h in dogs and 50-100 mg total daily dose in cats are recommended to achieve median CSS associated with clinical remission. Due to the large pharmacokinetic variability, individualized dose adjustments based on CSS (therapeutic drug monitoring) and treatment failure should be considered.

Effects of dietary energy level and intake of corn by-product-based diets on antibody production, acute phase protein response, stress, and immunocompetency of healthy and morbid newly received growing cattle were evaluated. Four dietary treatments were formulated to supply 0.99, 1.10, 1.21, and 1.32 Mcal NE(g)/ kg DM and were offered at 100%, 95%, 90%, and 85% of ad libitum based on 0.99/100 treatment intake, respectively. Thirty-two pens were utilized with approximately 12 animals/pen. Four animals from each pen (32/dietary treatment) were randomly selected and used to serve as a subset to monitor immune function and acute phase proteins following a split-plot design. In addition, two animals were randomly and independently selected from each pen (16/dietary treatment) and used to measure fecal cortisol metabolite. Additionally, animals removed from the pen one (M1), two (M2), or three (M3) times and classified as morbid were bled in conjunction with a healthy control (H) removed at the same time and the serum analyzed for the same parameters. A quadratic response to time (P < 0.01) was detected for haptoglobin concentrations and for antibody titers for bovine viral diarrhea type 1 (BVD-I) and infectious bovine rhinotracheitis (IBR; P < 0.01). Haptoglobin was lowest on arrival, highest on day 14, and similar to baseline levels by day 27. Titer levels for BVD-I and IBR were lowest on arrival, higher on day 14, and significantly higher on day 27. Titers for bovine viral diarrhea type 2 (BVD-II) responded linearly (P < 0.05) with lower levels on arrival and highest levels on day 27. Haptoglobin was elevated in morbid animals compared to healthy pen mates (P < 0.05). Titer levels for BVD-I and IBR were also higher in healthy animals compared to animals pulled for morbidity (P < 0.01). Fecal cortisol was higher on arrival than on day 14 (P < 0.05). Dietary treatment had no effect on any of the parameters investigated. In summary, high-energy receiving diets based on fermentable fiber from by-products can be fed to newly received growing cattle without negative effects on antibody production toward vaccines, inflammation, or overall stress. In addition, haptoglobin concentrations and titer levels for BVD-I and IBR viruses are higher in healthy animals compared to sick animals.

OBJECTIVE To determine the clinical manifestations of histoplasmosis in a large sample of dogs, compare outcomes achieved with fluconazole versus itraconazole, and identify variables available at the time of diagnosis with prognostic value. DESIGN Retrospective case series with nested cohort study. ANIMALS 79 dogs with confirmed histoplasmosis evaluated at 2 veterinary teaching hospitals from 1999 through 2015. PROCEDURES Medical records were reviewed and data extracted regarding clinical signs at evaluation, physical examination findings, clinical laboratory values, other diagnostic test results, treatments, and outcomes. Data were compared between antifungal agents used (fluconazole or itraconazole) and between other variables. RESULTS Various breeds were represented. Working and herding breeds had mostly disseminated histoplasmosis, and toy breeds had mostly the gastrointestinal form. The diagnosis was often achieved with noninvasive techniques, such as cytologic evaluation of rectal scrape samples (n = 24) or blood films (15). Clinical remission was achieved in 16 of 25 (64%) dogs receiving fluconazole and 17 of 24 (71%) dogs receiving itraconazole. No differences were identified between antifungal agents in survival, clinical remission, or disease relapse rates. Identified negative prognostic factors included Great Pyrenees breed, dyspnea, need for oxygen supplementation, icterus, palpable abdominal organomegaly, anemia, thrombocytopenia, hypercalcemia, high serum alkaline phosphatase activity, and hyperbilirubinemia, whereas diarrhea was a positive prognostic factor. CONCLUSIONS AND CLINICAL RELEVANCE Findings suggested that histoplasmosis should be considered in a sick dog of any breed in an endemic area. Clinical signs may be nonspecific. Diagnosis may often be possible with noninvasive and inexpensive tests. Either fluconazole or itraconazole may be an effective treatment option.

Objective To determine reference intervals and the effect of sample agitation and rest time on Sonoclot analysis in healthy adult horses. Design Original prospective study. Setting University veterinary medical teaching hospital. Animals Sixty healthy adult horses. Interventions Blood was collected for assessment of complete blood count, serum biochemical analysis, and Sonoclot analysis. Measurements and main results Horses were determined to be healthy based upon physical examination, CBC, and serum biochemistry analysis. Blood was analyzed in a glass bead-containing cuvette using the Sienco Sonoclot analyzer following 2 rest periods (30 mins and 240 min) and with 2 sample handling interventions (agitated and nonagitated), to obtain values for clot rate, time-to-peak, activated clotting time, and platelet function. This study failed to detect a significant difference when a rest time of 30 minutes was compared with 240 minutes, but based on wide limits of agreement the 2 rest times were not considered interchangeable. Agitation at both rest times significantly affected all Sonoclot analyses leading to changes indicative of hypercoagulability. Conclusions Sample agitation and rest time should be taken into consideration when developing preanalytical guidelines for Sonoclot analysis in horses. Calculated reference intervals were relatively wide. Further research is needed to evaluate the clinical utility of Sonoclot analysis in horses.

Peripheral nerve injuries can significantly reduce quality of life. While some recover, most do not recover fully, resulting in neuropathic pain and loss of sensation and motor function. Research on the mechanisms of peripheral nerve regeneration could elucidate poor patient outcomes and potential treatments. This study was designed to determine if brain derived neurotrophic factor (BDNF) is necessary for pudendal nerve regeneration and functional recovery. Peripheral administration of tyrosine kinase B functional chimera (TrkB) was used to inhibit the BDNF regenerative pathway. Female Sprague-Dawley rats received tyrosine kinase B functional chimera (TrkB) or saline after a pudendal nerve crush (PNC) or Sham PNC and were divided into three groups: Sham PNC, PNC + Saline, and PNC + TrkB. Seven days after injury, relative βII tubulin expression (1.0 ± 0.2) was significantly decreased after PNC + TrkB compared to PNC + saline (2.9 ± 1.0). Three weeks after injury, BDNF plasma concentration (1320.8 ± 278.1 pg/ml) was significantly reduced in PNC + TrkB compared to PNC + saline rats (2053.4 ± 211.0 pg/ml). Pudendal nerve motor branch firing rate (54.0 ± 9.5 Hz) was significantly decreased in the PNC + TrkB group compared to the PNC + saline group (120.4 ± 17.1 Hz); while nerve firing rate of the PNC + saline group was not significantly different from sham PNC rats (121.8 ± 26.6 Hz). This study demonstrated that peripheral administration of TrkB bound free BDNF and inhibited the regenerative response after PNC. BDNF is necessary for normal PN motor branch recovery after PNC.

Background Treatment monitoring is subjective and disease relapse is common in cats with histoplasmosis. The Histoplasma antigen enzyme immunoassay (EIA) is a noninvasive test used for determining disease remission and detecting disease relapse in humans with histoplasmosis. The utility of the antigen EIA for these purposes in cats remains unknown. Hypothesis/Objectives Those Histoplasma antigen concentrations in urine and serum would decline with antifungal treatment and that antigen elimination would be an indicator of clinical remission in cats with histoplasmosis treated with antifungal treatment. Animals Fifteen client-owned cats with histoplasmosis. Methods Masked observational study. Cats were monitored monthly during antifungal treatment. Time of clinical remission and serum and urine antigen elimination were determined for each cat. Results Twelve of 15 cats achieved clinical remission. At the time of diagnosis, antigen was detectable in urine in 14/15 (93%) cats and in serum in 11/15 (73%) cats. Both serum (P < .0005) and urine (P < .0001) antigen concentrations significantly decreased over time with effective treatment. Antigen elimination was sensitive [urine, 90.0% (95% CI 72.3–97.4%); serum, 90.4% (68.2–98.3%)] but less specific [urine, 64.6% (51.7–75.8%); serum, 52.1% (37.4–66.5%)] for disease remission. Urine antigen was positive in both cats and serum antigen was positive in 1 cat at the time of disease relapse. Conclusions and Clinical Importance Measurement of Histoplasma antigen in urine and serum might be useful tests for determining disease remission and relapse in cats with histoplasmosis. Further research is needed to investigate the importance of low-level antigenemia and antigenuria.

The potential distribution of Amblyomma americanum ticks in Kansas was modeled using maximum entropy (MaxEnt) approaches based on museum and field-collected species occurrence data. Various bioclimatic variables were used in the model as potentially influential factors affecting the A. americanum niche. Following reduction of dimensionality among predictor variables using principal components analysis, which revealed that the first two principal axes explain over 87% of the variance, the model indicated that suitable conditions for this medically important tick species cover a larger area in Kansas than currently believed. Soil moisture, temperature, and precipitation were highly correlated with the first two principal components and were influential factors in the A. americanum ecological niche. Assuming that the niche estimated in this study covers the occupied distribution, which needs to be further confirmed by systematic surveys, human exposure to this known disease vector may be considerably under-appreciated in the state.

American Association of Bovine Practitioners Proceedings of the Annual Conference, 2018

New research tools are essential to help understand the neural control of the lower urinary tract (LUT). A more nuanced understanding of the neuroanatomy of bladder function could enable new treatment options or neuroprosthesis to eliminate incontinence. Here we describe the design, prototyping and validation of a sensing mechanism for a catheter-free fluid volume estimating system for chronic neurophysiological studies of the lower urinary tract and ambulatory urodynamics. The system consists of two stimulation electrodes, one sensing anode, and a microcontroller for control and recording. The packaged device is small enough to be surgically implanted within the bladder lumen, where it does not inhibit bladder function nor inflict trauma. Benchtop evaluation of the conductance-sensing system in simulated bladder-like conditions has demonstrated that the system can predict intra-vesical fluid volume to within ±20 mL (40%) from 0 to 50 mL with root-mean-square error of 11.32% over the same range. These results indicate that conductance-based volume sensing of the urinary bladder is a feasible method for real-time measurement.

Objectives The objective of this study was to determine if urine Histoplasma antigen (HAg) enzyme immunoassay (EIA) concentrations at the time of diagnosis and prior to the administration of antifungal agents are predictive of outcome for cats infected with Histoplasma capsulatum and to determine if compromised renal function affects urine HAg EIA measurements. Methods Medical records at four institutions were searched to identify cats diagnosed with histoplasmosis between April 2012 and December 2015. Pretreatment urine Histoplasma EIA values were recorded, along with patient signalment, serum creatinine concentration, urine specific gravity, site(s) of infection and survival data. Results Pretreatment urine HAg EIA measurements were available for 50 cats, and ranged from 0–19.1 ng/ml (median 6.3 ng/ml). Thirty-five cats were alive at day 180, 12 had died or were euthanized (median survival time 24 days; range 2–124 days) and three were lost to follow-up. The median urine HAg EIA at the time of diagnosis for cats alive at 6 months was 5 ng/ml (range 0–19.1); this was similar to findings for the non-survivors (median 7.29 ng/ml; range 0.78–19.1; P = 0.54). Surviving cats were significantly younger (mean age 6.9 years) than non-survivors (mean age 9.9 years; P = 0.03) but median body weights (3.8 kg vs 3.6 kg) and rates of pulmonary involvement (22/35 vs 9/12) were similar for the two groups. Median urine HAg EIA concentration was lower in cats with evidence of renal compromise than cats with acceptable renal function (0.54 ng/ml vs 7.2 ng/ml; P Conclusions and relevance Urine HAg EIA concentrations at the time of diagnosis are not predictive of outcome in cats with histoplasmosis and should not be used as a prognostic indicator in this species. Renal function may influence urine HAg EIA concentrations in cats; further investigation is needed to see if concurrent kidney disease impacts test sensitivity.