Advanced Meditation and Vegan Diet Increased Acylglycines and Reduced Lipids Associated with Improved Health: A Prospective Longitudinal Study.

Introduction: Samyama is an Isha Yoga 8-day residential meditation/yoga retreat combined with 60 days of preparation with vegan diet. We showed earlier Samyama retreat was associated with lower systemic inflammation and favorable lipid profiles along with other physical and mental health benefits. There is no mechanistic study on the impact of an advanced meditative process on multiple blood lipids and their implications on meditation-related improved physical and mental wellbeing. Methods: Sixty-four Samyama participants on vegan diet had blood sampled immediately before and immediately after the 8-day retreat for lipidomic analysis. The complex plasma lipidome was characterized using high-resolution mass spectrometric analysis and tandem mass spectrometry. Results: Pre- and post-Samyama blood samples of 64 Samyama participants were analyzed. Acylglycines (acetyl, propionyl, butyryl, and valeryl) were increased in the plasma post-Samyama compared with pre-Samyama (p < 0.001). Levels of glycerophosphocholines, glycerophosphoethanolamines, di-unsaturated ethanolamine plasmalogens, cholesterol esters, acylcarnitines, and acylgylcerines (triacylglycerols and diacylglycerols) decreased after the Samyama meditation. Plasma levels of glycerophosphoserines or glycerophosphoinositols were unchanged. Conclusion: An 8-day advanced meditation retreat resulted in increased acylglycines, an endocannabinoid-like fatty acid amide associated with increased cellular anandamide levels, anti-inflammation, analgesia, and vascular relaxation. Other serum lipid levels, including some that are associated with increased risk of atherosclerosis, were reduced following the Samyama program. ClinicalTrials.gov Registration: Identifier: NCT04366544.

Advanced Meditation Alters Resting-State Brain Network Connectivity Correlating With Improved Mindfulness.

Purpose: The purpose of this study was to investigate the effect of an intensive 8-day Samyama meditation program on the brain functional connectivity using resting-state functional MRI (rs-fMRI). Methods: Thirteen Samyama program participants (meditators) and 4 controls underwent fMRI brain scans before and after the 8-day residential meditation program. Subjects underwent fMRI with a blood oxygen level dependent (BOLD) contrast at rest and during focused breathing. Changes in network connectivity before and after Samyama program were evaluated. In addition, validated psychological metrics were correlated with changes in functional connectivity. Results: Meditators showed significantly increased network connectivity between the salience network (SN) and default mode network (DMN) after the Samyama program (p < 0.01). Increased connectivity within the SN correlated with an improvement in self-reported mindfulness scores (p < 0.01). Conclusion: Samyama, an intensive silent meditation program, favorably increased the resting-state functional connectivity between the salience and default mode networks. During focused breath watching, meditators had lower intra-network connectivity in specific networks. Furthermore, increased intra-network connectivity correlated with improved self-reported mindfulness after Samyama. Clinical Trials Registration: [https://clinicaltrials.gov], Identifier: [NCT04366544]. Registered on 4/17/2020.

The utility of Coccidioides antigen and antibody detection in cerebrospinal fluid in the diagnosis of canine central nervous system coccidioidomycosis.

OBJECTIVE: To evaluate the utility of enzyme immunoassays (EIAs) for the detection of Coccidioides antigen and antibody in CSF in the diagnosis of CNS coccidioidomycosis in dogs. ANIMALS: 51 dogs evaluated for CNS disease in a single specialty center in Tucson in 2016. PROCEDURES: Excess CSF after routine analysis was banked after collection from dogs presented to the neurology service. Samples were tested by EIA for presence of Coccidioides antigen and antibody. Clinical data were collected from medical records retrospectively. RESULTS: 22 dogs were diagnosed with CNS coccidioidomycosis (CCM) or another neurologic disease (non-CCM). These groups of dogs overlapped in the presenting complaints, MRI results, and routine CSF analysis results. Four dogs, all with CCM, had positive antigen EIA results. With clinical diagnosis used as the reference standard, CSF antigen testing had low sensitivity (20%) but high specificity (100%) for diagnosis of CCM. Ten dogs with CCM and 4 dogs with other diagnoses had antibody detected in CSF by EIA. Sensitivity of CSF antibody testing was 46%, specificity was 86%, and positive and negative predictive values for the study population were 71% and 68%, respectively. CLINICAL RELEVANCE: Diagnosis of CNS coccidioidomycosis in dogs in an endemic region was hampered by overlap of clinical signs with other neurologic disorders and the low sensitivity of confirmatory diagnostics. The evaluated Coccidioides-specific EIAs performed on CSF can aid in the diagnosis. A prospective study is warranted to corroborate and refine these preliminary findings.

Isha Yoga Practices and Participation in Samyama Program are Associated with Reduced HbA1C and Systemic Inflammation, Improved Lipid Profile, and Short-Term and Sustained Improvement in Mental Health: A Prospective Observational Study of Meditators.

Background: Meditation is gaining recognition as a tool to impact health and well-being. Samyama is an 8-day intensive residential meditation experience conducted by Isha Foundation requiring several months of extensive preparation and vegan diet. The health effects of Samyama have not been previously studied. The objective was to assess physical and emotional well-being before and after Samyama participation by evaluating psychological surveys and objective health biomarkers. Methods: This was an observational study of 632 adults before and after the Isha Samyama retreat. All participants were invited to complete surveys. Controls included household significant others. Surveys were completed at baseline (T1), just before Samyama (T2), immediately after Samyama (T3), and 3 months later (T4) to assess anxiety, depression, mindfulness, joy, vitality, and resilience through validated psychometric scales. Voluntary blood sampling for biomarker analysis was done to assess hemoglobin (Hb), HbA1c, lipid profile, and C-reactive protein (CRP). Primary outcomes were changes in psychometric scores, body weight, and blood biomarkers. Results: Depression and anxiety scores decreased from T1 to T3, with the effect most pronounced in participants with baseline depression or anxiety. Scores at T4 remained below baseline for those with pre-existing depression or anxiety. Vitality, resilience, joy, and mindfulness increased from T1 to T3 (sustained at T4). Body weight decreased by 3% from T1 to T3. Triglycerides (TG) were lower from T2 to T3. Participants had lower HbA1c and HDL at T2, and lower CRP at all timepoints compared with controls. Conclusions: Participation in the Isha Samyama program led to multiple benefits. The 2-month preparation reduced anxiety, and participants maintained lower anxiety levels at 3 months post-retreat. Physical health improved over the course of the program as evidenced by weight loss and improved HbA1C and lipid profile. Practices associated with the Samyama preparation phase and the retreat may serve as an effective way to improve physical and mental health. Future studies may examine their use as an alternative therapy in patients with depression and/or anxiety. Clinical Trial Registration: www.ClinicalTrials.gov, Identifier: 1801728792. Registered retrospectively on 4/17/2020.

Pharmacogenomics of oxycodone: a narrative literature review.

Oxycodone is a semisynthetic µ- and κ-opioid receptor with agonist with a broad scope of use including postoperative analgesia as well as control of neuropathic and cancer pain. Advantages over other opioids include prolonged duration of action, greater potency than morphine and lack of histamine release or ceiling effect. Individual responses to oxycodone can vary due to genetic differences. This review article aims to summarize the oxycodone literature and provide context on its pharmacogenomics and pharmacokinetics. The evidence for clinical effect of genetic polymorphisms on oxycodone is conflicting. There is stronger evidence linking polymorphic genetic enzymes CYP2D6 and CYP3A with therapeutic outcomes. Further, research is needed to discern all of oxycodone's metabolites and their contribution to the overall analgesic effect.

A Novel Perioperative Multidose Methadone-Based Multimodal Analgesic Strategy in Children Achieved Safe and Low Analgesic Blood Methadone Levels Enabling Opioid-Sparing Sustained Analgesia With Minimal Adverse Effects.

BACKGROUND: Intraoperative methadone, a long-acting opioid, is increasingly used for postoperative analgesia, although the optimal methadone dosing strategy in children is still unknown. The use of a single large dose of intraoperative methadone is controversial due to inconsistent reductions in total opioid use in children and adverse effects. We recently demonstrated that small, repeated doses of methadone intraoperatively and postoperatively provided sustained analgesia and reduced opioid use without respiratory depression. The aim of this study was to characterize pharmacokinetics, efficacy, and safety of a multiple small-dose methadone strategy. METHODS: Adolescents undergoing posterior spinal fusion (PSF) for idiopathic scoliosis or pectus excavatum (PE) repair received methadone intraoperatively (0.1 mg/kg, maximum 5 mg) and postoperatively every 12 hours for 3-5 doses in a multimodal analgesic protocol. Blood samples were collected up to 72 hours postoperatively and analyzed for R-methadone and S-methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidene (EDDP) metabolites, and alpha-1 acid glycoprotein (AAG), the primary methadone-binding protein. Peak and trough concentrations of enantiomers, total methadone, and AAG levels were correlated with clinical outcomes including pain scores, postoperative nausea and vomiting (PONV), respiratory depression, and QT interval prolongation. RESULTS: The study population included 38 children (10.8-17.9 years): 25 PSF and 13 PE patients. Median total methadone peak plasma concentration was 24.7 (interquartile range [IQR], 19.2-40.8) ng/mL and the median trough was 4.09 (IQR, 2.74-6.4) ng/mL. AAG concentration almost doubled at 48 hours after surgery (median = 193.9, IQR = 86.3-279.5 µg/mL) from intraoperative levels (median = 87.4, IQR = 70.6-115.8 µg/mL; P < .001), and change of AAG from intraoperative period to 48 hours postoperatively correlated with R-EDDP (P < .001) levels, S-EDDP (P < .001) levels, and pain scores (P = .008). Median opioid usage was minimal, 0.66 (IQR, 0.59-0.75) mg/kg morphine equivalents/d. No respiratory depression (95% Wilson binomial confidence, 0-0.09) or clinically significant QT prolongation (median = 9, IQR = -10 to 28 milliseconds) occurred. PONV occurred in 12 patients and was correlated with morphine equivalent dose (P = .005). CONCLUSIONS: Novel multiple small perioperative methadone doses resulted in safe and lower blood methadone levels, <100 ng/mL, a threshold previously associated with respiratory depression. This methadone dosing in a multimodal regimen resulted in lower blood methadone analgesia concentrations than the historically described minimum analgesic concentrations of methadone from an era before multimodal postoperative analgesia without postoperative respiratory depression and prolonged corrected QT (QTc). Larger studies are needed to further study the safety and efficacy of this methadone dosing strategy.

Peer Support in the Treatment of Chronic Pain in Adolescents: A Review of the Literature and Available Resources.

Peer support has found applications beyond the mental health field and is useful for managing several chronic disorders and supporting healthy lifestyle choices. Communication through telephone and the Internet allows for greater access to those who cannot meet in person. Adolescent chronic pain would seem ideally suited to benefit from online peer support groups. Research is lacking, however, to characterize benefit in terms of pain and function, despite a clear desire among adolescents for access to such programs. More rapid development of online applications is needed for peer support, and research into the associated outcomes will be necessary to optimally design such programs.

Pharmacogenomics of methadone: a narrative review of the literature.

Background: Methadone, a synthetic opioid with longer duration of action and lower abuse potential compared with morphine, is used to prevent opioid withdrawal, as well as to manage chronic and acute surgical pain. The variability in response to methadone has been widely recognized. The purpose of this article is to review the literature on the pharmacogenetic factors underlying this variability. Materials & methods: This is a narrative overview of the literature on the genetic variants affecting pharmacodynamics and pharmacokinetics of methadone, retrieved from searches of databases such as PubMed and google scholar. Discussion: Clinical responses to methadone may be affected by genetic variants in the opioidergic, dopaminergic and neurotrophic pathways. Polymorphisms in genes related to disposition and elimination of methadone alter the pharmacokinetics, and possibly pharmacodynamics of methadone. Cytochrome P450 enzymes and P-glycoprotein variants contribute to the interindividual variability in methadone pharmacokinetics. Evidence for single gene variants affecting methadone response remains weak. Multiple genetic variants must be considered in conjunction to improve predictive ability. Conclusion: Evidence remains scarce at this time, to recommend pharmacogenetic testing before methadone administration. Well-powered clinical studies are needed with population pharmacokinetic-pharmacodynamic modeling and multigenetic signature-based predictions to enable tailored use of methadone in clinical practice.

Inner Engineering Practices and Advanced 4-day Isha Yoga Retreat Are Associated with Cannabimimetic Effects with Increased Endocannabinoids and Short-Term and Sustained Improvement in Mental Health: A Prospective Observational Study of Meditators.

BACKGROUND: Anxiety and depression are common in the modern world, and there is growing demand for alternative therapies such as meditation. Meditation can decrease perceived stress and increase general well-being, although the physiological mechanism is not well-characterized. Endocannabinoids (eCBs), lipid mediators associated with enhanced mood and reduced anxiety/depression, have not been previously studied as biomarkers of meditation effects. Our aim was to assess biomarkers (eCBs and brain-derived neurotrophic factor [BDNF]) and psychological parameters after a meditation retreat. METHODS: This was an observational pilot study of adults before and after the 4-day Isha Yoga Bhava Spandana Program retreat. Participants completed online surveys (before and after retreat, and 1 month later) to assess anxiety, depression, focus, well-being, and happiness through validated psychological scales. Voluntary blood sampling for biomarker studies was done before and within a day after the retreat. The biomarkers anandamide, 2-arachidonoylglycerol (2-AG), 1-arachidonoylglycerol (1-AG), docosatetraenoylethanolamide (DEA), oleoylethanolamide (OLA), and BDNF were evaluated. Primary outcomes were changes in psychological scales, as well as changes in eCBs and BDNF. RESULTS: Depression and anxiety scores decreased while focus, happiness, and positive well-being scores increased immediately after retreat from their baseline values (P < 0.001). All improvements were sustained 1 month after BSP. All major eCBs including anandamide, 2-AG, 1-AG, DEA, and BDNF increased after meditation by > 70% (P < 0.001). Increases of ≥20% in anandamide, 2-AG, 1-AG, and total AG levels after meditation from the baseline had weak correlations with changes in happiness and well-being. CONCLUSIONS: A short meditation experience improved focus, happiness, and positive well-being and reduced depression and anxiety in participants for at least 1 month. Participants had increased blood eCBs and BDNF, suggesting a role for these biomarkers in the underlying mechanism of meditation. Meditation is a simple, organic, and effective way to improve well-being and reduce depression and anxiety.

Personalized pediatric anesthesia and pain management: problem-based review.

Pharmacogenetics, the genetic influence on the interpersonal variability in drug response, has enabled tailored pharmacotherapy and emerging 'personalized medicine.' Although oncology spearheaded the clinical implementation of personalized medicine, other specialties are rapidly catching up. In anesthesia, classical examples of genetically mediated idiosyncratic reactions have been long known (e.g., malignant hyperthermia and prolonged apnea after succinylcholine). The last two decades have witnessed an expanding body of pharmacogenetic evidence in anesthesia. This review highlights some of the prominent pharmacogenetic associations studied in anesthesia and pain management, with special focus on pediatric anesthesia.

Novel canine anti-Coccidioides immunoglobulin G enzyme immunoassay aids in diagnosis of coccidioidomycosis in dogs.

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.

Comparison of Compounded, Generic, and Innovator-Formulated Itraconazole in Dogs and Cats.

The triazole antifungal itraconazole may be cost prohibitive in brand name form; therefore, compounded and generic products are often used as alternatives. Itraconazole blood concentrations have not been studied in clinical patients receiving these formulations. Itraconazole bioassay was performed on serum/plasma from 95 dogs and 20 cats receiving itraconazole (compounded from bulk powder, generic pelletized, or brand name) for systemic mycosis treatment. Mean itraconazole concentration was lower in the compounded group (n = 42) as compared with the generic (n = 40) or brand name (n = 33) groups (0.5 µg/mL versus 8.3 µg/mL and 6.5 µg/mL, respectively; P < .001). No statistical difference was observed between itraconazole concentrations in the generic and brand name groups. Forty animals (95.2%) in the compounded group had subtherapeutic (<1.0 µg/mL) values. All cats in this group (n = 10) had undetectable itraconazole concentrations. Some animals in the generic and brand name groups had subtherapeutic values (12.5 and 12.1%, respectively) or potentially toxic values (>10 µg/mL; 37.5 and 24%, respectively). Compounded itraconazole should be avoided, but generic itraconazole appears to serve as a reasonable alternative to brand name itraconazole. Therapeutic drug monitoring may be beneficial in all cases.

Reduced susceptibility to fluconazole in a cat with histoplasmosis.

CASE SUMMARY: An 11-year-old neutered male domestic longhair cat was diagnosed with histoplasmosis from fine-needle aspirates of an abdominal lymph node. Lymph node size initially decreased with fluconazole therapy (11.8 mg/kg PO q12h); however, after 13 months of continuous fluconazole therapy, lymphadenomegaly worsened and samples were collected for culture and antifungal susceptibility. The Histoplasma capsulatum isolate had a very high fluconazole minimum inhibitory concentration (MIC) of 64 µg/ml and an itraconazole MIC of 0.06 µg/ml. The owner declined a change to itraconazole and, ultimately, the cat developed neurologic signs and was euthanized. Owing to the initial response to fluconazole followed by treatment failure and high MIC value, acquired fluconazole resistance was suspected. Clinical breakpoints for fluconazole for the dimorphic fungi are not available to define true antifungal resistance. RELEVANCE AND NOVEL INFORMATION: This is the first published report of reduced susceptibility to fluconazole in a cat being treated for histoplasmosis. Fluconazole failure and increases in MIC between pretreatment and long-term treatment isolates are known to occur in humans with histoplasmosis. Practitioners should be aware of this possibility when treating cats with fluconazole (particularly in cases with long-term [>1 year] fluconazole therapy or in cases with disease recrudescence).

Evaluation of an enzyme immunoassay for antibodies to a recombinant Blastomyces adhesin-1 repeat antigen as an aid in the diagnosis of blastomycosis in dogs.

OBJECTIVE: To evaluate the sensitivity and specificity of an enzyme immunoassay (EIA) for antibodies to a recombinant Blastomyces adhesin-1 repeat antigen (rBAD-1) to aid in the diagnosis of blastomycosis in dogs and compare the findings with results from other tests used for this purpose. DESIGN: Prospective analytic study. SAMPLE: Serum and urine from 70 dogs with and without blastomycosis. PROCEDURES: Serum and urine samples were collected from dogs with blastomycosis (n = 21), histoplasmosis (8), or nonfungal pulmonary disease (21) and from healthy control dogs living in a blastomycosis-endemic area (20). Serum was tested for antibodies against Blastomyces dermatitidis with the rBAD-1 antibody EIA and an A-antigen antibody agar gel immunodiffusion (AGID) assay. Serum and urine were tested for B dermatitidis antigen with a quantitative EIA. RESULTS: Sensitivity of the quantitative antigen EIA was 100% in serum and urine samples from dogs with blastomycosis, with specificity of 95% in urine samples from dogs with nonfungal pulmonary disease and 100% in urine samples from healthy dogs. Sensitivity of the rBAD-1 antibody EIA (95%) was significantly greater than that of the A-antigen antibody AGID assay (65%). Specificity of the antibody EIA was 88% in dogs with histoplasmosis, 95% in healthy dogs, and 100% in dogs with nonfungal pulmonary disease. CONCLUSIONS AND CLINICAL RELEVANCE: The rBAD-1 antibody EIA had greater sensitivity than the A-antigen antibody AGID assay in dogs with blastomycosis. This antibody EIA may assist in distinguishing histoplasmosis from blastomycosis. Further evaluation in a larger prospective study is needed to verify these results.

Identification of Parabodo caudatus (class Kinetoplastea) in urine voided from a dog with hematuria.

A voided urine sample, obtained from a 13-year-old intact male dog residing in a laboratory animal research facility, was observed to contain biflagellate protozoa 5 days following an episode of gross hematuria. The protozoa were identified as belonging to the class Kinetoplastea on the basis of light microscopic observation of Wright-Giemsa-stained urine sediment in which the kinetoplast was observed basal to 2 anterior flagella. A polymerase chain reaction (PCR) assay using primers corresponding with conserved regions within the 18S ribosomal RNA gene of representative kinetoplastid species identified nucleotide sequences with 100% identity to Parabodo caudatus. Parabodo caudatus organisms were unable to be demonstrated cytologically or by means of PCR in samples collected from the dog's environment. The dog had a history of 50 complete urinalyses performed over the 12-year period preceding detection of P. caudatus, and none of these were noted to contain protozoa. Moreover, the gross hematuria that was documented 5 days prior to detection of P. caudatus had never before been observed in this dog. Over the ensuing 2.5 years of the dog's life, 16 additional complete urinalyses were performed, none of which revealed the presence of protozoa. Bodonids are commonly found in soil as well as in freshwater and marine environments. However, P. caudatus, in particular, has a 150-year-long, interesting, and largely unresolved history in people as either an inhabitant or contaminant of urine. This historical conundrum is revisited in the current description of P. caudatus as recovered from the urine of a dog.

What is your diagnosis? Abdominal mass aspirate in a cat with an increased Na:K ratio.

A 13-year-old domestic shorthair cat was presented for evaluation of pollakiuria. Laboratory abnormalities included mild hypercholesterolemia, moderate hypertriglyceridemia, and a mild increase in the Na:K ratio (43, reference interval 32-41). Abdominal ultrasonography revealed urinary calculi and a soft tissue mass between the right caudate liver lobe and the right kidney. Surgery was done to remove the cystic calculi, and aspirates of the mass were obtained. Cytologic specimens contained a population of large, round to angular cells with round nuclei, coarse irregularly stippled chromatin, 1-2 prominent round to angular nucleoli, and abundant pale basophilic cytoplasm distended by numerous well-delineated vacuoles. Rare binucleated cells and micronuclei, and moderate anisocytosis, anisokaryosis, and anisonucleoleosis were noted. The cytologic interpretation was adrenal neoplasia, consistent with adrenal carcinoma. Approximately 4 months later, the cat developed vomiting, dehydration, weakness, and cervical ventroflexion. Serum biochemical alterations at that time included marked hypokalemia (2.4 mmol/L, reference interval 3.4-5.6 mmol/L) and a markedly increased Na:K ratio (65, reference interval 32-41). Mean systolic blood pressure was 205 mmHg. Surgical removal of the mass was accomplished via right adrenalectomy and a diagnosis of adrenal carcinoma was confirmed histologically. Plasma aldosterone concentration (measured preoperatively) was 1358 pmol/L (reference interval 194-388 pmol/L). Primary hyperaldosteronism caused by a functional adrenal carcinoma is an uncommon condition in cats.

What is your diagnosis? Particulate material in peritoneal fluid from a dog.

9-year-old castrated male Greyhound dog was presented for evaluation of vomiting and lethargy of 1-week duration. On physical examination, the dog was febrile and dehydrated with a tense abdomen and petechial hemorrhages. Clinicopathologic abnormalities included relative polycythemia, mild lymphopenia with reactive lymphocytes, hypoalbuminemia, hypocholesterolemia, hyperbilirubinemia, increased ALP, mild hypokalemia, hyperamylasemia, hyperlipasemia, increased D-dimer concentration, and hyperfibrinogenemia. Cytologic evaluation of peritoneal fluid revealed marked suppurative inflammation with intracellular barium sulfate particles. The day before presentation, the referring veterinarian had administered oral barium sulfate in an upper gastrointestinal contrast study. Radiographs revealed free contrast material in the peritoneal cavity, consistent with gastrointestinal perforation, and leakage of contrast material. Abdominal exploratory surgery revealed a mid-jejunal perforation and a hepatic nodule. Histopathologic diagnosis of the jejunal and liver lesions was T-cell lymphoma. The patient recovered well postoperatively and received chemotherapy for treatment of lymphoma. Most commercial barium sulfate preparations contain relatively uniform, weakly birefringent, pale yellow particles <1 microm in diameter. Because barium sulfate is found occasionally in clinical specimens, cytopathologists should be familiar with its cytologic appearance.