Cystine and urate cystoliths in dogs are frequently visible on radiographs prior to surgical or nonsurgical removal.

OBJECTIVE: To investigate the frequency at which cystine and urate cystoliths (stones) are visible on radiographs prior to surgical or nonsurgical retrieval. METHODS: Records of client-owned dogs (n = 331) were analyzed between January 2019 and December 2023 for cystoliths submitted for stone analysis after surgical removal or nonsurgical retrieval. Records were analyzed for cystolith type; when cystine or urate stones were identified, records were analyzed for signalment, procedure, presence of mineral opaque cystoliths on pre-procedural radiographs, urine pH and crystalluria, history of previous cystoliths, prior prescription diet attempt, recurrence, and genetic, congenital and acquired comorbidities. Descriptive statistics were generated after data collection. RESULTS: 31 of 331 (9%) were cystine stones, 49 of 331 (15%) were urate, and 1 of 331 (0.3%) was a mix of urate and cystine. When radiographs were taken prior to stone removal, 24 of 28 (85%) of urate, 24 of 26 (92%) of cystine, and 1 of 1 (100%) of urate/cystine were visible on radiographs. CONCLUSIONS: Cystine and urate stones are visible on survey radiography at a high frequency in dogs. CLINICAL RELEVANCE: While cystine and urate stones have been historically designated as radiolucent, they are frequently radiopaque on radiographs. Radiopacity is commonly used as one of the criterion to determine whether a dissolution or prevention diet is an appropriate management technique, particularly when determination of the stone type has yet to be performed. As a result, these findings may prompt clinicians to investigate other patient-specific factors before a specific dietary recommendation is made.

Cooled feline intestine and fresh intestine did not differ in enterotomy leak pressure testing or in gross wall thickness measurement.

OBJECTIVE: To report gross anatomical gastrointestinal measurements and compare enterotomy leak pressures between fresh and cooled feline cadavers. STUDY DESIGN: Ex vivo, randomized study. ANIMALS: Fresh feline cadavers (n = 20). METHODS: Jejunal segments (8 cm) were harvested on the same day as euthanasia. From each cadaver, one segment was randomly assigned to control (C), fresh enterotomy (FE), and cooled enterotomy (CE) groups. Enterotomy construction and leak testing were performed within 12 h of euthanasia for the C and FE groups and after 17-29 h of cooling for the CE group. Initial leak pressure (ILP) and maximum intraluminal pressure (MIP) were compared. Gastrointestinal wall thickness and intraluminal diameter were measured on harvested applicable gastrointestinal divisions at up to three time points: day 1 fresh, day 2 cooled, and day 3 cooled. RESULTS: The mean (± SD) ILPs for the C, FE, and CE constructs were 600 (± 0.0), 200.3 (± 114.7), and 131.3 (± 92.6) mmHg, respectively. The C ILP was higher (p < .001) than the FE and CE ILP. The ILP (p = .11) and the MIP (p = .21) did not differ between the FE and CE constructs. Wall thickness (measured in mm) did not differ between duodenum day 1 fresh and day 2 cooled groups (p = .18) or between any jejunum day groups (p = .86). The intraluminal diameters (mean ± SD) for the duodenum, jejunum, and ileum were 5.7 (± 0.7), 5.8 (± 0.8), and 7.2 (± 2.2) mm, respectively. CONCLUSION: No difference was appreciated between FE and CE ILP and MIP. Wall thickness measurements did not differ between days for duodenum or jejunum. CLINICAL RELEVANCE: Cadaveric feline intestine cooled for up to 29 h may be used for determining intestinal leak pressures.

Hepatic insufficiency in two juvenile dogs with histoplasmosis.

A 9-month-old female intact toy poodle and a 1-year-old female intact Labrador retriever mix presented to separate teaching hospitals for chronic histories of malaise and clinicopathologic evidence of hepatic dysfunction. The signalment and clinical histories of these dogs prompted consideration of a congenital portosystemic shunt as a primary differential. However, microscopic evaluation of peritoneal effusion, pleural effusion, and peripheral blood samples from the dogs revealed round to ovoid yeast organisms morphologically most compatible with Histoplasma capsulatum. Additional testing confirmed histoplasmosis in each case. The poodle underwent a computed tomography (CT) study, which showed hepatomegaly with a spleno-gonadal shunt, pancreatic and gastric wall edema, and marked peritoneal effusion, findings compatible with portal hypertension and secondary acquired shunt formation. The dog was later humanely euthanized due to clinical deterioration, and on necropsy hepatic histoplasmosis was verified, with additional affected tissues comprising lungs and spleen. The Labrador Retriever mix responded clinically and clinicopathologically to antifungal therapy, though no abdominal imaging was performed to definitively exclude the possibility of a congenital portosystemic shunt. In retrospect, several features were more compatible with histoplasmosis than portosystemic shunt in these cases, including hyperbilirubinemia, effusion, and hepatomegaly. These findings serve as a reminder of the need to interpret serum biochemical findings in the context of the totality of the clinicopathologic data and imaging findings, as well as the diagnostic value of microscopy in the evaluation of hematologic and body cavity fluid samples.

Anatomical classification of feline congenital extrahepatic portosystemic shunts based on CT angiography: A SVSTS and VIRIES multi-institutional study in 231 cats.

The prevalence of anatomical-based subtypes of feline congenital extrahepatic portosystemic shunts (EHPSS) has not been completely elucidated. The goal of this study was to use CT angiography to create an anatomical-based nomenclature system for feline congenital EHPSS. Additionally, subjective portal perfusion scores were generated to determine if intrinsic portal vein development was associated with different shunt conformations or patient age at the time of CT. The SVSTS and VIRIES list services were used to recruit cases. Data collected included patient DOB, gender, breed, weight, CT date, and reported diagnosis. Shunts were classified based upon (1) the shunt portal vessel(s) of origin, (2) the shunt systemic vessel(s) of insertion, and (3) any substantial portal vessels contributing to the shunt. Additionally, hepatic portal perfusion was subjectively scored between 1 (poor/none) and 5 (good/normal) based on the caliber of the intrahepatic PVs. A total of 264 CT scans were submitted from 29 institutions. Due to exclusion criteria, 33 (13%) were removed, leaving 231 CT scans to be included. Twenty-five different EHPSS anatomies were identified with five classifications accounting for 78% of all shunts (LGP [53%], LGC-post [11%], LCG [7%], LGC-pre [4%], and PC [4%]). Shunt origin involved the left gastric vein in 75% of the described classifications. Significant differences were identified among the five most common shunt types with respect to age at the time of CT scan (P = .002), breed (P < .001), and subjective portal perfusion score (P < .001). This refined anatomical classification system for feline EHPSS may enable improved understanding, treatment comparisons, and outcome prediction for cats with these anomalies.

Beta-Lactam Allergy De-labeling in a Pediatric Hospital.

OBJECTIVE: To assess the ability to de-label pediatric patients of their beta-lactam allergy by using a newly implemented institutional protocol and to identify potential barriers to the de-labeling process. METHODS: All patients with reported allergies to prespecified beta-lactam antibiotics were eligible for a -beta-lactam allergy interview. Following the interview, patients were grouped into 4 risk categories-no risk, low risk, moderate risk, and high risk-and assessed for intervention eligibility. Potential interventions included de-labeling based on the interview alone or proceeding to an oral amoxicillin challenge with or without penicillin allergy skin testing. RESULTS: Of the 62 patients eligible for beta-lactam allergy interviews, 40% (n = 25) were de-labeled. Among de-labeled patients, 60% (n = 15) were de-labeled on the basis of the interview alone. Additionally, no failures were documented in patients who underwent an oral amoxicillin challenge or penicillin skin testing. Barriers to performing oral amoxicillin challenges or penicillin skin testing included concomitant systemic steroid or antihistamine use, refusal of intervention, and insufficient resources to perform penicillin skin testing. CONCLUSIONS: There was a high frequency of patients de-labeled of their beta-lactam allergies in this study. Increased education to patients, parents, and providers on the de-labeling process, as well as increased personnel available to coordinate and perform de-labeling interventions, may result in more beta-lactam allergy de-labeling.

Diagnostic and Prognostic Performance of Metabolic Signatures in Pancreatic Ductal Adenocarcinoma: The Clinical Application of Quantitative NextGen Mass Spectrometry.

With 64,050 new diagnoses and 50,550 deaths in the US in 2023, pancreatic ductal adenocarcinoma (PDAC) is among the most lethal of all human malignancies. Early detection and improved prognostication remain critical unmet needs. We applied next-generation metabolomics, using quantitative tandem mass spectrometry on plasma, to develop biochemical signatures that identify PDAC. We first compared plasma from 10 PDAC patients to 169 samples from healthy controls. Using metabolomic algorithms and machine learning, we identified ratios that incorporate amino acids, biogenic amines, lysophosphatidylcholines, phosphatidylcholines and acylcarnitines that distinguished PDAC from normal controls. A confirmatory analysis then applied the algorithms to 30 PDACs compared with 60 age- and sex-matched controls. Metabolic signatures were then analyzed to compare survival, measured in months, from date of diagnosis to date of death that identified metabolite ratios that stratified PDACs into distinct survival groups. The results suggest that metabolic signatures could provide PDAC diagnoses earlier than tumor markers or radiographic measures and offer insights into disease severity that could allow more judicious use of therapy by stratifying patients into metabolic-risk subgroups.

Computed tomographic characteristics of confirmed and presumed noncutaneous pythiosis in 25 dogs.

Pythium insidiosum is an aquatic oomycete that causes granulomatous infection in dogs, most commonly cutaneous and gastrointestinal. Ultrasonographic characteristics of gastrointestinal pythiosis have been described; occasionally, CT is utilized in the clinical setting, and CT features of pythiosis have not been published. The purpose of this retrospective, multicenter, descriptive study is to describe CT characteristics of noncutaneous canine pythiosis. The following CT parameters were recorded: lesion anatomic location, number, shape, margination, size, attenuation pre- and postcontrast, enhancement pattern, lymph nodes affected, other lesions identified, and presence of peritoneal effusion or steatitis. Descriptive statistics demonstrating the frequency of lesion appearances were performed. Twenty-five dogs with noncutaneous pythiosis lesions that underwent CT were included; 19 had primarily gastrointestinal infections, four primarily arterial infections, one intrathoracic and intra-abdominal infection, and one primary pulmonary infection. In dogs with primary gastrointestinal infection, lesions were most common at the ileocolic junction and were most frequently focal, well-defined, moderate to marked circumferential wall thickening that was homogeneous and smoothly marginated precontrast, with moderate heterogeneous contrast enhancement. Most dogs had involvement of multiple gastrointestinal regions. Of four dogs with primary arterial involvement, three had large aneurysmal dilatations of the cranial mesenteric artery with severe mural thickening. All dogs had regional lymphadenopathy, which was variable but generally mild. Nine dogs had peritoneal effusion; six dogs had steatitis. CT features of pythiosis can overlap with neoplasia, but pythiosis should be considered as a differential, especially in young dogs. Findings supported using CT as an adjunct imaging test for increasing clinical suspicion of noncutaneous pythiosis.

Treatments and Severe Outcomes for Patients Diagnosed With MIS-C at Four Children's Hospitals in the United States, March 16, 2020-March 10, 2021.

BACKGROUND: Clinical management of multisystem inflammatory syndrome in children (MIS-C) has varied over time and by medical institution. METHODS: Data on patients with MIS-C were collected from 4 children's hospitals between March 16, 2020 and March 10, 2021. Relationships between MIS-C treatments and patient demographics, clinical characteristics, and outcomes were described. Propensity score matching was utilized to assess the relative risk of outcomes dependent on early treatment with intravenous immunoglobulin (IVIG) or low-dose steroids, controlling for potential confounding variables. RESULTS: Of 233 patients diagnosed with MIS-C, the most commonly administered treatments were steroids (88.4%), aspirin (81.1%), IVIG (77.7%) and anticoagulants (71.2%). Compared with those patients without respiratory features, patients with respiratory features were less likely to receive IVIG and steroids on the same day (combination treatment) (44.1%). Controlling for confounding variables, patients receiving IVIG within 1 day of hospitalization were less likely to have hospital length of stay ≥8 days (RR = 0.53, 95% CI: 0.31-0.88). Patients receiving low-dose steroids within 1 day of hospitalization were less likely to develop ventricular dysfunction (RR = 0.45, 95% CI: 0.26-0.77), have increasingly elevated troponin levels (RR = 0.55, 95% CI: 0.40-0.75) or have hospital length of stay ≥8 days (RR = 0.46, 95% CI: 0.29-0.74). CONCLUSION: Treatments for MIS-C differed by hospital, patient characteristics and illness severity. When IVIG and low-dose steroids were administered in combination or low-dose steroids were administered alone within 1 day of hospitalization, the risk of subsequent severe outcomes was decreased.

Laparoscopic ultrasonography of the liver is feasible and safe in dogs.

OBJECTIVE: To describe the feasibility and technique for performing laparoscopic ultrasound (LUS) of the liver in dogs. ANIMALS: 12 client-owned dogs presenting for elective laparoscopic surgery from January 1, 2022, to October 31, 2022. METHODS: Laparoscopic exploration and LUS of the liver were performed in all dogs. Dogs were positioned in reverse Trendelenburg and laterally rotated to facilitate access to all liver lobes. Time to perform laparoscopic exploration and LUS, ability to visualize and access each liver lobe entirely, and any complications were recorded. Each dog underwent an elective laparoscopic procedure. The surgeon completed a National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire after surgery. RESULTS: Mean body weight was 25.9 kg (SD, ± 4.1 kg; range, 5.7 to 62 kg). All liver lobes were scanned to the level of the hilus in 10/12 dogs. In 2 dogs, the caudate lobe could not be completely imaged. Median time to perform LUS was 9 minutes (IQR, 5 to 16.5 minutes), and median NASA-TLX score was 9/100 (IQR, 6.3 to 20). There was a significantly strong negative correlation between time to perform LUS (r = -0.77; P = .0037) and NASA-TLX score (r = -0.84; P = .0006) with trial number. Minor complications occurred in 2 dogs during laparoscopic exploration. No complications occurred during LUS. CLINICAL RELEVANCE: LUS was feasible and safe in all dogs. The right lateral and caudate lobes were occasionally challenging to access. Technical demand and time to perform LUS improved with experience, suggesting a learning curve. Evaluation of LUS in dogs with clinical disease is warranted.

A Novel Standardized Method for Aiding to Determine Left Atrial Enlargement on Lateral Thoracic Radiographs in Dogs.

BACKGROUND: Left atrial enlargement indicates severe cardiac disease. Although the gold standard for determining left atrial size is echocardiography, many veterinary practices lack the necessary equipment and expertise. Therefore, thoracic radiography is often used to differentiate cardiogenic pulmonary edema from primary respiratory diseases and to facilitate distinguishing dogs with stage B1 and B2 mitral valve degeneration. METHODS: The goal was to test a new standardized method for identifying radiographic left atrial enlargement. On a lateral radiograph, a straight line was drawn from the dorsal border of the tracheal bifurcation to the crossing point of the dorsal border of the caudal vena cava and the most cranial crus of the diaphragm. If a part of the left atrium extended this line dorsally, it was considered enlarged. Echocardiographic left atrial to aortic ratio (LA:Ao) was used as a reference. Thirty-nine observers with various levels of experience evaluated 90 radiographs, first subjectively, then applying the new method. RESULTS: The new method moderately correlated with LA:Ao (r = 0.56-0.66) in all groups. The diagnostic accuracy (72-74%) of the subjective assessment and the new method showed no difference. CONCLUSIONS: Though the new method was not superior to subjective assessment, it may facilitate learning and subjective interpretation.

Radiographic and ultrasonographic appearance of a jejunal torsion-volvulus in a dog.

A 1.5-year-old male neutered, 5 kg, Dachshund was referred for anorexia and vomiting for several days' duration. Radiographs revealed concern for a small intestinal obstruction. Ultrasonography revealed a severely distended segment of jejunum containing echogenic fluid that abruptly narrowed, twisted, and transitioned into normal jejunum, along with the presence of a distinct "whirl sign" that resulted from the intestinal segments twisting around themselves. This, in addition to the absence of flow on power Doppler interrogation, was compatible with a focal jejunal torsion-volvulus. The torsion-volvulus was surgically confirmed, a resection and anastomosis was performed, and the dog recovered uneventfully.

Computed tomographic features of double aortic arch in six dogs.

Double aortic arch (DAA) is a rare, congenital anomaly in small animals, resulting in a complete vascular ring encircling the esophagus and trachea, and subsequent compression of these organs. Few studies have reported utilizing CT angiography (CTA) for diagnosing DAA in dogs; thus, the imaging features are currently lacking in the literature. The objectives of this retrospective, multicenter, descriptive case series were to report the clinical and CTA characteristics of DAA in surgically treated cases. Medical records and CTA images were reviewed. Six juvenile dogs met the inclusion criteria (median age: 4.2 months; range: 2-5 months). The most common clinical signs included chronic regurgitation (100%), decreased body condition (67%), and coughing (50%). Common CTA features of DAA included a dominant left aortic arch (median diameter: 8.1 mm) and minor right aortic arch (median diameter: 4.3 mm; 83%), an aberrant right subclavian artery arising directly from the right aortic arch (83%), segmental esophageal constriction (100%), and variable degrees of dilation cranial to the heart base, and marked tracheal luminal compression (median percent change: -55%; 100%) and leftward curvature of the trachea at the level of the bifurcation of the aortic arches (100%). All dogs underwent successful surgical correction with only minor postoperative complications. Due to the similarity of clinical and imaging characteristics described to that of other forms of vascular ring anomalies (VRA), CTA is vital for the specific diagnosis of DAA in dogs.

Disseminated mycobacterial infections after tumor necrosis factor inhibitor use, revealing inborn errors of immunity.

Tumor necrosis factor-a inhibitors can be associated with increased risk of infections, particularly reactivation of latent tuberculosis or nontuberculous mycobacterium (NTM). However, because disseminated NTM is rare, inborn errors of immunity should be considered. We present three patients with disseminated NTM after tumor necrosis factor-a inhibitor use who were found to have inborn errors of immunity.

Serologic responses to COVID-19 vaccination in children with history of multisystem inflammatory syndrome (MIS-C).

Understanding the serological responses to COVID-19 vaccination in children with history of MIS-C could inform vaccination recommendations. We prospectively enrolled seven children hospitalized with MIS-C and measured SARS-CoV-2 binding IgG antibodies to spike protein variants longitudinally pre- and post-Pfizer-BioNTech BNT162b2 primary series COVID-19 vaccination. We found that SARS-CoV-2 variant cross-reactive IgG antibodies variably waned following acute MIS-C, but were significantly boosted with vaccination and maintained for up to 3 months. We then compared post-vaccination binding, pseudovirus neutralizing, and functional antibody-dependent cell-mediated cytotoxicity (ADCC) titers to the reference strain (Wuhan-hu-1) and Omicron variant (B.1.1.529) among previously healthy children (n = 16) and children with history of MIS-C (n = 7) or COVID-19 (n = 8). Despite the breadth of binding antibodies elicited by vaccination in all three groups, pseudovirus neutralizing and ADCC titers were significantly reduced to the Omicron variant.

COVID-19 Vaccine Reactogenicity and Vaccine Attitudes Among Children and Parents/Guardians After Multisystem Inflammatory Syndrome in Children or COVID-19 Hospitalization: September 2021-May 2022.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) is a multiorgan hyperinflammatory condition following SARS-CoV-2 infection. Data on COVID-19 vaccine adverse events and vaccine attitudes in children with prior MIS-C are limited. We described characteristics associated with COVID-19 vaccination, vaccine adverse events and vaccine attitudes in children with a history of MIS-C or COVID-19 and their parents/guardians. METHODS: We enrolled children previously hospitalized for MIS-C or COVID-19 from 3 academic institutions. We abstracted charts and interviewed children and parents/guardians regarding vaccine adverse events and acceptability. RESULTS: Of 163 vaccine-eligible children enrolled with a history of MIS-C and 70 with history of COVID-19, 51 (31%) and 34 (49%), respectively, received mRNA COVID-19 vaccine a median of 10 (Interquartile Range 6-13) months after hospital discharge. Among 20 children with MIS-C and parents/guardians who provided interviews, local injection site reaction of brief duration (mean 1.8 days) was most commonly reported; no children required medical care within 2 weeks postvaccination. Vaccine survey results of interviewed, vaccinated children and their parents/guardians: of 20 children with MIS-C and 15 children with COVID-19, 17 (85%) and 13 (87%), respectively, listed doctors in the top 3 most trusted sources for vaccine information; 13 (65%) and 9 (60%) discussed vaccination with their doctor. CONCLUSIONS: COVID-19 vaccination was well tolerated in children with prior MIS-C or COVID-19 participating in our investigation. Parents/guardians regarded their children's doctors as a trusted source of information for COVID-19 vaccines, and most vaccinated children's parents/guardians had discussed COVID-19 vaccination for their child with their doctor.

Serologic Responses to COVID-19 Vaccination in Children with History of Multisystem Inflammatory Syndrome (MIS-C)

Understanding the serological responses to COVID-19 vaccination in children with history of MIS-C could inform vaccination recommendations. We prospectively enrolled five children hospitalized with MIS-C and measured SARS-CoV-2 binding IgG antibodies to spike protein variants longitudinally pre- and post-Pfizer-BioNTech BNT162b2 primary series COVID-19 vaccination. We found that SARS-CoV-2 variant cross-reactive IgG antibodies waned following acute MIS-C, but were significantly boosted with vaccination and maintained for at least 3 months. We then compared post-vaccination binding, pseudovirus neutralizing, and functional antibody-dependent cell-mediated cytotoxicity (ADCC) titers to the reference strain (Wuhan-hu-1) and Omicron variant (B.1.1.529) among previously healthy children (n=6) and children with history of MIS-C (n=5) or COVID-19 (n=5). Despite the breadth of binding antibodies elicited by vaccination in all three groups, pseudovirus neutralizing and ADCC titers were reduced to the Omicron variant. Vaccination after MIS-C or COVID-19 (hybrid immunity) conferred advantage in generating pseudovirus neutralizing and functional ADCC antibodies to Omicron.