A Fermented Wheat Germ Extract Contains Protein Components Active against NSCLC Xenografts In Vivo.

Non-small cell lung cancer (NSCLC) continues to be the leading cause of cancer-related deaths. Although advances have been made in the past decade to treat such tumors, most options induce multiple side effects, and many patients discontinue therapy due to toxicity. Thus, the need remains for non-toxic, effective NSCLC therapies, especially in an elderly patient population. Our lab has previously identified a protein fraction from the nutraceutical Avemar®-dubbed fermented wheat germ protein (FWGP)-with demonstrated efficacy in lymphoma models both in vitro and in vivo. Here, we show that FWGP also has anti-tumor activity in vitro and in vivo against lung cancer. In vitro cytotoxicity against multiple lung cancer cell lines yielded IC50 values comparable to those previously established with the parent product, Avemar. Further, significant A549 xenograft growth inhibition occurred in athymic nu/nu mice receiving FWGP in both pre-radiated and non-radiated models when compared to the untreated control. Encouragingly, mice treated with FWGP experienced no toxicities as detected by weight reduction or blood chemistry analysis. These data support the further study of FWGP as a potential non-toxic therapy for lung cancer and other oncologic indications.

Pro-Inflammatory Alterations of Circulating Monocytes in Latent Tuberculosis Infection.

Background: Latent tuberculosis infection (LTBI) has been associated with increased cardiovascular risk. We investigated the activation and pro-inflammatory profile of monocytes in individuals with LTBI and their association with coronary artery disease (CAD). Methods: Individuals 40-70 years old in Lima, Peru, underwent QuantiFERON-TB testing to define LTBI, completed a coronary computed tomography angiography to evaluate CAD, and provided blood for monocyte profiling using flow cytometry. Cells were stimulated with lipopolysaccharide to assess interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α responses. Results: The clinical characteristics of the LTBI (n = 28) and non-LTBI (n = 41) groups were similar. All monocyte subsets from LTBI individuals exhibited higher mean fluorescence intensity (MFI) of CX3CR1 and CD36 compared with non-LTBI individuals. LTBI individuals had an increased proportion of nonclassical monocytes expressing IL-6 (44.9 vs 26.9; P = .014), TNF-α (62.3 vs 35.1; P = .014), and TNF-α+IL-6+ (43.2 vs 36.6; P = .042). Among LTBI individuals, CAD was associated with lower CX3CR1 MFI on classical monocytes and lower CD36 MFI across all monocyte subsets. In multivariable analyses, lower CD36 MFI on total monocytes (b = -0.17; P = .002) and all subsets remained independently associated with CAD in LTBI. Conclusions: Individuals with LTBI have distinct monocyte alterations suggestive of an exacerbated inflammatory response and tissue migration. Whether these alterations contribute to cardiovascular disease pathogenesis warrants further investigation.

Effects on Tissue Integration of Collagen Scaffolds Used for Local Delivery of Gentamicin in a Rat Mandible Defect Model.

Surgical site infections (SSIs) are a common complication following orthopedic surgery. SSIs may occur secondary to traumatic or contaminated wounds or may result from invasive procedures. The development of biofilms is often associated with implanted materials used to stabilize injuries and to facilitate healing. Regardless of the source, SSIs can be challenging to treat. This has led to the development of devices that act simultaneously as local antibiotic delivery vehicles and as scaffolds for tissue regeneration. The goal for the aforementioned devices is to increase local drug concentration in order to enhance bactericidal activity while reducing the risk of systemic side effects and toxicity from the administered drug. The aims of this study were to assess the effect of antibiotic loading of a collagen matrix on the tissue integration of the matrix using a rat mandibular defect model. We hypothesized that the collagen matrix could load and elute gentamicin, that the collagen matrix would be cytocompatible in vitro, and that the local delivery of a high dose of gentamicin via loaded collagen matrix would negatively impact the tissue-scaffold interface. The results indicate that the collagen matrix could load and elute the antimicrobial gentamicin and that it was cytocompatible in vitro with or without the presence of gentamicin and found no significant impact on the tissue-scaffold interface when the device was loaded with a high dose of gentamicin.

Preoperative symptom duration does not affect clinical outcomes after high tibial osteotomy at a minimum of 2-year follow-up.

OBJECTIVES: To determine if patients with preoperative symptom durations greater than two-years' experience inferior patient-reported and clinical outcomes at a minimum of two years after high tibial osteotomy. METHODS: An institutional registry was retrospectively queried for patients treated with high tibial osteotomy for symptomatic medial knee overload/arthritis and varus malalignment between February 2006 and March 2018. Demographic characteristics, clinical outcomes, patient-reported outcomes (PROs), including the International Knee Documentation Committee â€‹score, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement â€‹and Patient-Reported Outcome Measurement Information System Pain Interference â€‹and Physical Function â€‹scores, were assessed at a minimum of two-years postoperatively. Patients were compared based on preoperative symptom duration greater than or less than two years. Correlation coefficients were used to analyse the association between patient demographics and postoperative outcomes for the overall patient sample. RESULTS: A total of 41 patients were included in the analysis with a mean age (± standard deviation) of 37.0 â€‹± â€‹8.2 years and body mass index of 27.6 â€‹± â€‹4.2 â€‹kg/m2. The median (interquartile range) follow-up time for the entire study sample was 48.5 (24-100.5) months. There were no significant differences in delta (pre-to-post improvement) or postoperative PRO scores, number or time-to-reoperation â€‹or conversion to TKA (all P â€‹> â€‹0.05) based on the preoperative duration of symptoms. A statistically significant but weak correlation was observed between greater age (r â€‹= â€‹0.344, P â€‹= â€‹0.027) and BMI (r â€‹= â€‹0.320, P â€‹= â€‹0.044) with conversion to TKA. CONCLUSION: Patients with a preoperative duration of symptomatic medial knee overload/arthritis of two years or greater do not experience inferior PRO or clinical outcomes than patients with a symptom duration of less than 2 years at mid-term follow-up. Greater age and BMI were weakly correlated with conversion to TKA. Greater age was negatively correlated with undergoing at least one reoperation. LEVEL OF EVIDENCE: IV; Retrospective case series.

Development of a polymeric biomedical device platform with controlled disassembly and in vivo testing in a swine intestinal model.

The aim of this study was to create a surgical guide platform that maintains its integrity while the surgeon performs an intestinal anastomosis or another similar procedure, which then breaks apart and is eliminated from the body in a controlled manner. The device contains mixed polymeric structures that give it a controlled rate of disassembly that could meet the requirements of a specific surgical purpose. The intraluminal anastomotic guide was manufactured as a hollow cylinder composed of layers of porous polyurethane/PCL with polyvinylpyrrolidone as the binding agent similar to a "brick-mortar" architecture. This combination of polymeric structures is a promising manufacturing method from which a variety of tunable devices can be fabricated for specific medical procedures and site-specific indications. The guide was designed to rapidly disassemble within the intestinal lumen after use, reliably degrading while maintaining sufficient mechanical rigidity and stability to support manipulation during complex surgical procedures. The nature of the device's disassembly makes it suitable for use in hollow structures that discharge their contents, resulting in their elimination from the body. A swine model of intestinal anastomosis was utilized to validate the use and function of the device.

Predictive value of incidental right ventricular abnormalities identified on SPECT for mortality and pulmonary hypertension.

BACKGROUND: The clinical significance of incidentally found RV abnormalities on low-risk SPECT studies is not well-defined. The objective of this study was to determine the predictive value of incidental right ventricular (RV) abnormalities identified on single photon emission computed tomography (SPECT) scans for mortality and pulmonary hypertension (PH). METHODS: We retrospectively analyzed all low-risk SPECT studies in patients without known coronary artery or pulmonary vascular disease, performed at our institution, from 2007-2020. Adjusted Cox proportional hazards models were used to evaluate the association between incidental RV abnormalities on low-risk SPECT studies and outcomes. RESULTS: Of the 4761 patients included in the analysis, mortality events were present in 494, and echocardiographic PH was present in 619. Incidental RV abnormalities on low-risk SPECT studies were significantly and independently associated with all-cause mortality (HR = 1.41, CI [1.07-1.86], P = 0.0152) and echocardiographic PH (HR = 2.06, CI [1.64-2.60], P < 0.0001). CONCLUSIONS: These data suggest incidental RV abnormalities found on low-risk SPECT imaging studies are significantly and independently associated with increased mortality and risk of developing echocardiographic PH, and could identify high-risk patients for closer monitoring and additional diagnostic testing.

Pulmonary silicosis in 2 rock hyraxes, and literature review.

Two rock hyraxes (Procavia capensis), from the Chattanooga Zoo, were submitted separately for autopsy at the University of Tennessee Veterinary Medical Center. The first was a 4-y-old intact female that died without premonitory signs and the second was a 10-y-old intact male that was euthanized because of severe renal disease. Microscopically, the lungs of both hyraxes had multifocal-to-coalescing, <1-mm diameter aggregates of epithelioid macrophages separated by streams of fibrous tissue. Macrophages contained intracytoplasmic, clear, acicular, birefringent crystals. Transmission electron microscopy and energy-dispersive x-ray spectroscopy findings on the lung samples were consistent with silica crystal deposition. The hyraxes had been housed together on commercially sourced play sand composed of 99-99.5% quartz, a crystalline silica polymorph. The microscopic findings, transmission electron microscopy, and energy-dispersive x-ray spectroscopy of the intrahistiocytic crystals, in addition to the history of exposure to crystalline silica, were consistent with pulmonary silicosis. Pulmonary silicosis has not been reported previously in rock hyraxes, to our knowledge.

Influence of a novel scaffold composed of polyurethane, hydroxyapatite, and decellularized bone particles on the healing of fourth metacarpal defects in mares.

OBJECTIVE: To determine the effect of a novel scaffold, designed for use in bone regeneration, on healing of splint bone segmental defects in mares. STUDY DESIGN: In vivo experimental study. SAMPLE POPULATION: Five adult mares (4-10 years old; mean weight, 437.7 kg ± 29 kg). METHODS: Bilateral 2-cm full-thickness defects were created in the fourth metacarpal bones (MCIV) of each horse. Each defect was randomly assigned to either a novel scaffold treatment (n = 5) or an untreated control (n = 5). The scaffold was composed of polyurethane, hydroxyapatite, and decellularized bone particles. Bone healing was assessed for a period of 60 days by thermography, ultrasonography, radiography, and computed tomography (CT). Biopsies of each defect were performed 60 days after surgery for histological evaluation. RESULTS: On the basis of radiographic analysis, scaffold-treated defects had greater filling (67.42% ± 26.7%) compared with untreated defects (35.88% ± 32.7%; P = .006). After 60 days, CT revealed that the density of the defects treated with the scaffolds (807.80 ± 129.6 Hounsfield units [HU]) was greater than density of the untreated defects (464.80 ± 81.3 HU; P = .004). Evaluation of histology slides provided evidence of bone formation within an average of 9.43% ± 3.7% of the cross-sectional area of scaffolds in contrast to unfilled defects in which connective tissue was predominant throughout the biopsy specimens. CONCLUSION: The novel scaffold was biocompatible and supported bone formation within the MCIV segmental defects. CLINICAL SIGNIFICANCE: This novel scaffold offers an effective option for filling bone voids in horses when support of bone healing is indicated.

Leveraging copper import by yersiniabactin siderophore system for targeted PET imaging of bacteria.

There is an emerging need for accurate and rapid identification of bacteria in the human body to achieve diverse biomedical objectives. Copper homeostasis is vital for the survival of bacterial species owing to the roles of the metal as a nutrient, respiratory enzyme cofactor, and a toxin. Here, we report the development of a copper-64-labeled bacterial metal chelator, yersiniabactin, to exploit a highly conserved metal acquisition pathway for noninvasive and selective imaging of bacteria. Compared with traditional techniques used to manufacture probes, our strategy simplifies the process considerably by combining the function of metal attachment and cell recognition to the same molecule. We demonstrate, for the first time to our knowledge, how a copper-64 PET probe can be used to identify specific bacterial populations, monitor antibiotic treatment outcomes, and track bacteria in diverse niches in vivo.

Discrete binding patterns of two heparin-reactive proteins, basic fibroblast growth factor and peptide p5R, in amyloid-laden and healthy mice.

Peptide p5R is a synthetic, polybasic, heparin-binding peptide that preferentially reacts with amyloid deposits in vivo and in tissue sections. Basic fibroblast growth factor (bFGF1) similarly interacts with heparin-like molecules, notably heparan sulfate proteoglycans (HSPG), in the extracellular matrix and on cell surfaces. The aim of this study was to compare the biodistribution of p5R and bFGF in healthy mice as well as those with systemic inflammation-associated amyloidosis (AA), which contains HSPG, by using SPECT/CT imaging, tissue biodistribution measurements and micro-autoradiography. Although both proteins are known to bind heparan sulfate, their biodistribution was remarkably different in the healthy and diseased animals. Imaging revealed uptake of both radiolabeled proteins in the liver, spleen, and kidneys of mice with amyloidosis; however, 125I-bFGF, but not 125I-p5R, was observed in normal tissue at sites of HSPG expression, including the hepatic and splenic sinusoids and renal glomerulae. Microautoradiography demonstrated that while p5R bound exclusively to amyloid deposits in the spleen and liver of AA mice, bFGF had a broader binding pattern. Consequently, even though bFGF and p5R both interact with heparan sulfate moieties, p5R binding was restricted to HSPG in amyloid deposits and did not bind HSPG in healthy tissues, whereas bFGF preferentially reacted with HSPG in normal tissue. The data suggest that peptide p5R selectively binds HSPG in amyloid and that the HSPG in healthy tissue, recognized by bFGF, is not targeted by the peptide.

Development and in vivo Assessment of a Rapidly Collapsible Anastomotic Guide for Use in Anastomosis of the Small Intestine: A Pilot Study Using a Swine Model.

Various conditions in human and veterinary medicine require intestinal resection and anastomosis, and complications from these procedures are frequent. A rapidly collapsible anastomotic guide was developed for small intestinal end-to-end anastomosis and was investigated in order to assess its utility to improve the anastomotic process and to potentially reduce complication rates. A complex manufacturing method for building a polymeric device was established utilizing biocompatible and biodegradable polyvinylpyrrolidone and polyurethane. This combination of polymers would result in rapid collapse of the material. The guide was designed as a hollow cylinder composed of overlaying shingles that separate following exposure to moisture. An in vivo study was performed using commercial pigs, with each pig receiving one standard handsewn anastomosis and one guide-facilitated anastomosis. Pigs were sacrificed after 13 days, at which time burst pressure, maximum luminal diameter, and presence of adhesions were assessed. Burst pressures were not statistically different between treatment groups, but in vivo anastomoses performed with the guide withstood 10% greater luminal burst pressure and maintained 17% larger luminal diameter than those performed using the standard handsewn technique alone. Surgeons commented that the addition of a guide eased the performance of the anastomosis. Hence, a rapidly collapsible anastomotic guide may be beneficial to the performance of intestinal anastomosis.

Novel mTORC1 Inhibitors Kill Glioblastoma Stem Cells.

Glioblastoma (GBM) is an aggressive tumor of the brain, with an average post-diagnosis survival of 15 months. GBM stem cells (GBMSC) resist the standard-of-care therapy, temozolomide, and are considered a major contributor to tumor resistance. Mammalian target of rapamycin Complex 1 (mTORC1) regulates cell proliferation and has been shown by others to have reduced activity in GBMSC. We recently identified a novel chemical series of human-safe piperazine-based brain-penetrant mTORC1-specific inhibitors. We assayed the piperazine-mTOR binding strength by two biophysical measurements, biolayer interferometry and field-effect biosensing, and these confirmed each other and demonstrated a structure-activity relationship. As mTORC1 is altered in human GBMSC, and as mTORC1 inhibitors have been tested in previous GBM clinical trials, we tested the killing potency of the tightest-binding piperazines and observed that these were potent GBMSC killers. GBMSCs are resistant to the standard-of-care temozolomide therapy, but temozolomide supplemented with tight-binding piperazine meclizine and flunarizine greatly enhanced GBMSC death over temozolomide alone. Lastly, we investigated IDH1-mutated GBMSC mutations that are known to affect mitochondrial and mTORC1 metabolism, and the tight-binding meclizine provoked 'synthetic lethality' in IDH1-mutant GBMSCs. In other words, IDH1-mutated GBMSC showed greater sensitivity to the coadministration of temozolomide and meclizine. These data tend to support a novel clinical strategy for GBM, i.e., the co-administration of meclizine or flunarizine as adjuvant therapy in the treatment of GBM and IDH1-mutant GBM.

Retrospective investigation of Echinococcus canadensis emergence in translocated elk (Cervus canadensis) in Tennessee, USA, and examination of canid definitive hosts.

BACKGROUND: Few reports of Echinococcus spp. have been described in the USA; however, the geographical distribution of Echinococcus spp. in wild hosts is increasing consequent to human activities. In the early 2000's, 253 elk (Cervus canadensis) originating from Alberta, Canada were released into the Great Smoky Mountains National Park and North Cumberland Wildlife Management Area in an effort to re-establish their historical range. METHODS: We investigated the prevalence of Echinococcus spp. in re-established elk populations in the North Cumberland Wildlife Management Area and the Great Smoky Mountains National Park via a retrospective analysis of banked elk tissues and helminth examinations on intestinal contents from coyotes (Canis latrans) from the North Cumberland Wildlife Management Area. RESULTS: Four elk were PCR and sequence positive for E. canadensis. Each sequence had 98% or greater coverage and identity to multiple E. canadensis genotypes on GenBank. Adult Echinococcus spp. were not detected in any of the coyotes examined in this study. CONCLUSIONS: Continued surveillance of this disease in susceptible species in these areas is warranted, and these data further underscore the risk of zoonotic pathogen introduction secondary to wildlife translocation.

Compensatory combination of romidepsin with gemcitabine and cisplatin to effectively and safely control urothelial carcinoma.

BACKGROUND: Human urothelial carcinoma (UC) has a high tendency to recur and progress to life-threatening advanced diseases. Advanced therapeutic regimens are needed to control UC development and recurrence. METHODS: We pursued in vitro and in vivo studies to understand the ability of a triple combination of gemcitabine, romidepsin, and cisplatin (Gem+Rom+Cis) to modulate signalling pathways, cell death, drug resistance, and tumour development. RESULTS: Our studies verified the ability of Gem+Rom+Cis to synergistically induce apoptotic cell death and reduce drug resistance in various UC cells. The ERK pathway and reactive oxygen species (ROS) played essential roles in mediating Gem+Rom+Cis-induced caspase activation, DNA oxidation and damage, glutathione reduction, and unfolded protein response. Gem+Rom+Cis preferentially induced death and reduced drug resistance in oncogenic H-Ras-expressing UC vs. counterpart cells that was associated with transcriptomic profiles related to ROS, cell death, and drug resistance. Our studies also verified the efficacy and safety of the Gem plus Rom+Cis regimen in controlling UC cell-derived xenograft tumour development and resistance. CONCLUSIONS: More than 80% of UCs are associated with aberrant Ras-ERK pathway. Thus the compensatory combination of Rom with Gem and Cis should be seriously considered as an advanced regimen for treating advanced UCs, especially Ras-ERK-activated UCs.

Cardiac magnetic resonance imaging as a prognostic biomarker in treatment-naïve pulmonary hypertension.

PURPOSE: Targeted treatment for pulmonary arterial hypertension (PAH), diagnosed via right heart catheterization (RHC), has been shown to improve morbidity and mortality. Identifying characteristics that predict clinical worsening has been challenging. We sought to evaluate the role of cardiac Magnetic Resonance Imaging (CMR) as a predictor of clinical worsening in a cohort of treatment-naïve pulmonary hypertension (PH) patients. METHODS: We performed a retrospective single center analysis of all adults with newly diagnosed treatment-naïve PH between January 1st 2013 and January 1st 2019. Patients with World Health Organization (WHO)-Group I PAH or WHO-Group II/III PH disease, who underwent both CMR (Signa Horizon 1.5 T, General Electric, Milwaukee, WI and Siemens Espree 1.5 T, Munich, Germany) and RHC testing prior to targeted PAH treatment, were included for analysis. Cox proportional hazards models were constructed. RESULTS: A total of 38 patients, of which 12 (32 %) experienced the primary outcome of clinical worsening. were included in the final analysis, Patients with clinical worsening were significantly more likely to have RV dysfunction by CMR (including lower RV ejection fraction (HR 0.93, p = 0.007) and more RV dilation (HR 1.02, p = 0.005-0.021)) and RHC (including worse pulmonary vascular resistance (HR 1.32, p < 0.001)), even after adjustment for disease severity. Both CMR and RHC measures of RV dysfunction were found to be equally effective in predicting clinical worsening, regardless of PH etiology. CONCLUSIONS: In treatment-naïve PH patients, including those with WHO-Group II/III disease, both CMR and RHC measures independently and significantly predicted clinical worsening, even after adjustment for disease severity.

Detection of carcinogen-induced bladder cancer by fluorocoxib A.

BACKGROUND: Conventional cystoscopy can detect advanced stages of bladder cancer; however, it has limitations to detect bladder cancer at the early stages. Fluorocoxib A, a rhodamine-conjugated analog of indomethacin, is a novel fluorescent imaging agent that selectively targets cyclooxygenase-2 (COX-2)-expressing cancers. METHODS: In this study, we have used a carcinogen N-butyl-N-4-hydroxybutyl nitrosamine (BBN)-induced bladder cancer immunocompetent mouse B6D2F1 model that resembles human high-grade invasive urothelial carcinoma. We evaluated the ability of fluorocoxib A to detect the progression of carcinogen-induced bladder cancer in mice. Fluorocoxib A uptake by bladder tumors was detected ex vivo using IVIS optical imaging system and Cox-2 expression was confirmed by immunohistochemistry and western blotting analysis. After ex vivo imaging, the progression of bladder carcinogenesis from normal urothelium to hyperplasia, carcinoma-in-situ and carcinoma with increased Ki67 and decreased uroplakin-1A expression was confirmed by histology and immunohistochemistry analysis. RESULTS: The specific uptake of fluorocoxib A correlated with increased Cox-2 expression in progressing bladder cancer. In conclusion, fluorocoxib A detected the progression of bladder carcinogenesis in a mouse model with selective uptake in Cox-2-expressing bladder hyperplasia, CIS and carcinoma by 4- and 8-fold, respectively, as compared to normal bladder urothelium, where no fluorocoxib A was detected. CONCLUSIONS: Fluorocoxib A is a targeted optical imaging agent that could be applied for the detection of Cox-2 expressing human bladder cancer.

Exosomal markers (CD63 and CD9) expression and their prognostic significance using immunohistochemistry in patients with pancreatic ductal adenocarcinoma.

BACKGROUND: Exosomes are important mediators of intercellular communications and play pivotal roles in cancer progression, metastasis and chemoresistance. CD63 and CD9 are widely accepted exosomal markers. In patients with pancreatic ductal adenocarcinoma (PDAC), positive correlation between CD9 expression and overall survival (OS) was reported. CD63 expression was conserved in all patients with no reported prognostic significance. This study explored the prognostic significance of CD63 and CD9 expression using immunohistochemistry (IHC) in patients with PDAC of mixed racial background. METHODS: Between 2012 and 2016, 49 patients with PDAC had available tissues for CD63 and CD9 staining using IHC. Two pathologists independently scored the CD63 and CD9 expression. Staining intensity was graded from 1-3 and staining percentage was estimated in 10% increments. Mean Quick-score (Q-score) (Intensity X Percentage of staining) was calculated. RESULTS: The mean Q-score for CD63 and CD9 are higher in primary tumor from the pancreas compared to pancreatic tumor from metastatic sites (185 vs. 102, P=0.0002) and (48 vs. 20, P=0.0418) respectively. We fitted Cox proportion hazard regression models to investigate the impact of the covariates CD63 and CD9 on progression free survival (PFS) and OS. CD63 has significant impact on PFS (P=0.0135) and OS (P=0.003). The higher the CD63 Q-score, the longer the PFS and OS. CD9 doesn't have significant impact on PFS (P=0.5734) or OS (P=0.2682). The mean CD63 and CD9 Q-scores are slightly higher in African American (AA) compared to Caucasians (157 vs. 149, P=0.76) and (45 vs. 29, P=0.43) respectively. CONCLUSIONS: CD63 and CD9 expression is higher in primary tumor from the pancreas compared to pancreatic tumor from metastatic sites. There is correlation between CD63 expression (but not CD9 in this cohort) and PFS and OS. To our knowledge, this is the first study to show prognostic significance of CD63 expression in patients with PDAC using IHC. A trend of higher expression of CD63 and CD9 among AA compared to Caucasians was also noticed.

Fatal pulmonary hemorrhage associated with vascular amyloid deposition in a cat.

CASE SUMMARY: An adult female spayed Siamese-cross cat of unknown age was presented for bilateral hemorrhagic otorrhea. Nasopharyngeal polyps were diagnosed by CT and biopsy; bilateral ventral bulla osteotomies were performed. Episodic epistaxis, otic hemorrhage and hemoptysis with respiratory distress progressed over 18 months. Systolic blood pressure, complete blood count, plasma biochemistries, prothrombin time, partial thromboplastin time and coagulation factor 12, 9 and 8 activities were normal. Serial thoracic radiographs revealed patchy interstitial to alveolar patterns. Airway hemorrhage prevented diagnostic bronchoscopy. Respiratory hemorrhage was ultimately fatal. Amyloid deposition was identified in pulmonary vasculature, bronchial wall, lymphoid tissues, nasal-pharyngeal tissue and tympanic bullae based on microscopic examination and confirmed by Congo red staining with green birefringence under polarized light. RELEVANCE AND NOVEL INFORMATION: Amyloidosis should be considered as a differential diagnosis in cats with spontaneous hemorrhage of the respiratory or otic tracts. Although systemic amyloidosis is associated with a grave prognosis, this case suggests that prolonged survival is possible after the initial onset of signs in cats with pulmonary amyloidosis.