Hepatic copper accumulates in ferrets with and without hepatobiliary disease.

OBJECTIVE: To determine hepatic copper concentrations and zonal distribution in ferrets with and without hepatobiliary disease, validate rhodanine-based qualitative copper scoring and digital copper quantification in ferret hepatic samples, and ascertain whether clinical features predicted copper accumulation. ANIMALS: 34 ferrets, including 7 with necroinflammatory disease, 5 with hepatocellular carcinoma, 13 with non-necroinflammatory disease, and 9 with no hepatobiliary disease. PROCEDURES: Rhodanine-based digital copper quantification was validated by use of liver dually measured by atomic absorption spectroscopy and digital scanning (R2 = 0.98). Clinical features and hepatic copper scores and concentrations (dry weight liver) were compared between groups. Zonal copper distribution was determined. RESULTS: Hepatic copper concentration was strongly correlated with copper scores (ρ = 0.88). Ferrets with hepatobiliary disease were significantly older and had significantly higher serum alkaline phosphatase and γ-glutamyltransferase activities and creatinine concentrations. Centrilobular copper accumulated in 23 of 34 (64%) ferrets with (n = 15) and without (8) hepatobiliary disease. Median copper concentrations were not significantly different between ferrets with and without hepatobiliary disease but were significantly higher within neoplastic hepatic tissue in ferrets with hepatocellular carcinoma. Hepatic copper concentrations exceeded feline (> 180 µg/g) and canine (> 400 µg/g) reference limits in 19 and 9 ferrets, respectively. Hepatic copper > 1,000 µg/g occurred in 5 ferrets with and 2 without hepatobiliary disease. Clinical features did not predict copper accumulation. CLINICAL RELEVANCE: Rhodanine-based digital copper quantification and qualitative copper scoring discerned liver copper accumulation in ferrets. Ferrets with and without hepatobiliary disease displayed a propensity for centrilobular hepatic copper accumulation of uncertain clinical importance. Clinical and clinicopathologic features could not exclusively implicate pathologic copper accumulation.

Treatment and outcomes of dogs with hepatocutaneous syndrome or hepatocutaneous-associated hepatopathy.

BACKGROUND: Superficial necrolytic dermatitis (SND) in dogs is a rare disorder most commonly associated with hepatocutaneous syndrome. Although often reported as fatal, sporadically reported long-term remissions might be more common than previously believed and linked to treatment regimens. HYPOTHESIS/OBJECTIVES: Evaluate treatments and associated outcomes in dogs with hepatocutaneous-associated hepatopathy (HCH) with or without SND, designated collectively aminoaciduric canine hypoaminoacidemic hepatopathy syndrome (ACHES). ANIMALS: Forty-one dogs of various breeds and ages diagnosed with ACHES. METHODS: Retrospective study. Electronic surveys, medical records (2014-2019), and communication with veterinarians provided data. Three treatment categories were each dichotomized: IV amino acid (IV-AA) infusions (≥2 vs <2), supplements including S-adenosylmethionine (SAMe), arginine with ornithine, glutathione, lysine, proline, omega-3 fatty acids, or zinc (≥3 vs <3), and diet type (home-cooked vs commercial). Optimal treatment was defined as receiving ≥2 IV-AA treatments, ≥3 nutritional supplements, and a home-cooked diet. RESULTS: Most dogs (29/41, 71%) received IV-AA infusions (23/29, ≥2 infusions). Twenty-one dogs (51%) were fed commercial diets; 17/41 (41%) were fed home-cooked diets. Most dogs received SAMe (32/41, 78%) and a median of 3 supplements. In 4 dogs, HCH remission occurred. Overall all-cause median survival time (MST) was 359 days, and disease-specific MST was 557 days (range, 1-1783 days). Optimally treated dogs (n = 9) lived significantly longer (MST, >1783 days, P = .02) than variably treated dogs (MST, 214 days). CONCLUSIONS AND CLINICAL IMPORTANCE: Optimized ACHES management can resolve SND and HCH and confer long-term survival.

Bacterial culture and immunohistochemical detection of bacteria and endotoxin in cats with suppurative cholangitis-cholangiohepatitis syndrome.

OBJECTIVE: To characterize the frequency and type of bacterial infection by culture- and immunohistochemical (IHC)-based methods and determine the impact of infection on clinical features and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS). ANIMALS: 168 client-owned cats with S-CCHS (cases). PROCEDURES: Clinical features, bacterial culture results, culture-inoculate sources, and survival details were recorded. Cases were subcategorized by comorbidity (extrahepatic bile duct obstruction, cholelithiasis, cholecystitis, ductal plate malformation, biopsy-confirmed inflammatory bowel disease, and biopsy-confirmed pancreatitis) or treatment by cholecystectomy or cholecystoenterostomy. Culture results, bacterial isolates, Gram-stain characteristics, and IHC staining were compared among comorbidities. Lipoteichoic acid IHC staining detected gram-positive bacterial cell wall components, and toll-like receptor expression IHC reflected pathologic endotoxin (gram-negative bacteria) exposure. RESULTS: Clinical features were similar among cases except for more frequent abdominal pain and lethargy in cats with positive culture results and pyrexia, abdominal pain, and hepatomegaly for cats with polymicrobial infections. Bacteria were cultured in 93 of 135 (69%) cats, with common isolates including Enterococcus spp and Escherichia coli. IHC staining was positive in 142 of 151 (94%) cats (lipoteichoic acid, 107/142 [75%]; toll-like receptor 4, 99/142 [70%]). With in-parallel interpretation of culture and IHC-based bacterial detection, 154 of 166 (93%) cats had bacterial infections (gram-positive, 118/154 [77%]; gram-negative, 111/154 [72%]; polymicrobial, 79/154 [51%]). Greater frequency of bacterial isolation occurred with combined tissue, bile, and crushed cholelith inoculates. Infection and gram-positive bacterial isolates were associated with significantly shorter long-term survival times. CLINICAL RELEVANCE: S-CCHS was associated with bacterial infection, pathologic endotoxin exposure, and frequent polymicrobial infection in cats. Combined tissue inoculates improved culture detection of associated bacteria.

Clinical features, concurrent disorders, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome.

OBJECTIVE: To characterize clinical features, comorbidities, frequency of bacterial isolation, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS). ANIMALS: 168 client-owned cats with S-CCHS. PROCEDURES: Data were prospectively (1980 to 2019) collected regarding clinical features, comorbidities, bacterial infection, illness duration, and treatments. Variables were evaluated for associations with survival time. RESULTS: Median age of cats was 10.0 years, with no breed or sex predilection observed. Common clinical features included hyporexia (82%), hyperbilirubinemia (80%), lethargy (80%), vomiting (80%), jaundice (67%), weight loss (54%), and hypoalbuminemia (50%). Comorbidities included extrahepatic bile duct obstruction (53%), cholelithiasis (42%), cholecystitis (40%), and ductal plate malformation (44%) as well as biopsy-confirmed inflammatory bowel disease (60/68 [88%]) and pancreatitis (41/44 [93%]). Bacterial cultures were commonly positive (69%) despite prebiopsy antimicrobial administration in most cats. Of surgically confirmed choleliths, diagnostic imaging identified only 58%. Among 55 cats with "idiopathic pancreatitis," 28 (51%) were documented to have transiting choleliths, and 20 had pancreatic biopsies confirming pancreatitis. Cholelithiasis (with or without bile duct obstruction) and cholecystectomy were associated with survival advantages. Survival disadvantages were found for leukocytosis, ≥ 2-fold increased alkaline phosphatase, and hyperbilirubinemia. Cholecystoenterostomy had no survival impact. Cats with ductal plate malformations were significantly younger at diagnosis and death than other cats. Chronic treatments with antimicrobials, S-adenosylmethionine, and ursodeoxycholic acid were common postbiopsy. CLINICAL RELEVANCE: S-CCHS in cats was associated with bacterial infection and various comorbidities and may be confused with pancreatitis. Surgically correctable morbidities (ie, cholecystitis, cholecystocholelithiasis) and cholecystectomy provided a significant survival advantage.

Clinical features and amino acid profiles of dogs with hepatocutaneous syndrome or hepatocutaneous-associated hepatopathy.

BACKGROUND: Superficial necrolytic dermatitis (SND), hepatocutaneous-associated hepatopathy (HCH), aminoaciduria, and hypoaminoacidemia define hepatocutaneous syndrome (HCS) in dogs. Dogs without SND but that possess all other syndrome components are not well described. HYPOTHESIS/OBJECTIVES: To define an inclusive syndrome, aminoaciduric canine hypoaminoacidemic hepatopathy syndrome (ACHES) for dogs with HCH or HCS. Compare clinical features, salient clinicopathologic variables, and plasma and urine amino acid (AA) profiles among ACHES cases by skin lesion status. ANIMALS: Dogs of various breeds and ages diagnosed with ACHES (n = 41). A control (CON) cohort (n = 12) provided AA profile data. METHODS: Retrospective case series. Available medical records of previously identified cases were reviewed for salient clinical features and clinical pathology data. Plasma and urine AA profiles were performed. Cutaneous lesion status was classified as none, mild, or fulminant. RESULTS: Thirty cases (73%) developed SND at some time. Dogs with fulminant skin lesions at diagnosis (n = 22/41, 54%) had significantly lower hematocrit (P = .05) and mean corpuscular volume (P = .01) than dogs without SND. Principal component analysis of plasma AA profiles identified distinct clustering of CON from ACHES dogs, but not by skin lesion status. Plasma 1-methylhistidine (<7 nmol/mL) and cystathionine (<7.5 nmol/mL) were robust ACHES biomarkers. Urine lysine (>344 nmol/mg creatinine) and methionine (>68 nmol/mg creatinine) also were useful ACHES biomarkers. CONCLUSIONS AND CLINICAL IMPORTANCE: Specific AA biomarkers provide additional diagnostic utility in ACHES. Data suggests that HCH is an early stage, and SND a later stage manifestation of ACHES.

Relationships between congenital peritoneopericardial diaphragmatic hernia or congenital central diaphragmatic hernia and ductal plate malformations in dogs and cats.

OBJECTIVE: To characterize the association between peritoneopericardial diaphragmatic hernia (PPDH) or congenital central diaphragmatic hernia (CCDH) and ductal plate malformations (DPMs) in dogs and cats. ANIMALS: 18 dogs and 18 cats with PPDH or CCDH and 19 dogs and 18 cats without PPDH or CCDH. PROCEDURES: Evaluation of clinical details verified PPDH or CCDH and survival times. Histologic features of nonherniated liver samples were used to categorize DPM. Immunohistochemical staining for cytokeratin-19 distinguished bile duct profiles per portal tract and for Ki-67-assessed cholangiocyte proliferation. Histologic features of herniated liver samples from PPDH or CCDH were compared with those of pathological controls (traumatic diaphragmatic hernia, n = 6; liver lobe torsion, 6; ischemic hepatopathy, 2). RESULTS: DPM occurred in 13 of 18 dogs with the proliferative-like phenotype predominating and in 15 of 18 cats with evenly distributed proliferative-like and Caroli phenotypes. Congenital hepatic fibrosis DPM was noted in 3 dogs and 2 cats and renal DPM in 3 dogs and 3 cats. No signalment, clinical signs, or clinicopathologic features discriminated DPM. Kaplan Meier survival curves were similar in dogs and cats. Bile duct profiles per portal tract in dogs (median, 5.0; range, 1.4 to 100.8) and cats (6.6; 1.9 to 11.0) with congenital diaphragmatic hernias significantly exceeded those in healthy dogs (1.4; 1.2 to 1.6) and cats (2.3; 1.7 to 2.6). Animals with DPM lacked active cholangiocyte proliferation. Histologic features characterizing malformative bile duct profiles yet without biliary proliferation were preserved in herniated liver lobes in animals with DPM. CONCLUSIONS AND CLINICAL RELEVANCE: DPM was strongly associated with PPDH and CCDH. Because DPM can impact health, awareness of its coexistence with PPDH or CCDH should prompt biopsy of nonherniated liver tissue during surgical correction of PPDH and CCDH.

Disparities in hepatic copper concentrations determined by atomic absorption spectroscopy, inductively coupled plasma mass spectrometry, and digital image analysis of rhodanine-stained sections in dogs.

OBJECTIVE: To investigate disparities in hepatic copper concentrations determined by atomic absorption spectroscopy (AAS), inductively coupled plasma mass spectrometry (ICP-MS), and digital image analysis of rhodanine-stained sections. ANIMALS: 516 dogs. PROCEDURES: Medical records of dogs for which hepatic biopsy specimens had been submitted between January 1999 and December 2019 for evaluation of copper content were reviewed. Paired hepatic copper concentrations obtained with digital image analysis and AAS or ICP-MS were compared, and Spearman rank correlation coefficients were calculated to test for correlations between qualitative copper accumulation scores and hepatic copper concentrations. For dogs for which ≥ 4 rhodanine-stained hepatic sections were available, intraindividual variation in copper distribution across hepatic sections was evaluated. RESULTS: Median hepatic copper concentrations obtained with digital image analysis exceeded concentrations obtained with AAS or ICP-MS. Concentrations were also higher in older dogs (≥ 9 years vs < 9 years), dogs of breeds with a typical body weight ≥ 20 kg (44 lb), and dogs with necroinflammatory changes or uneven copper distribution. Qualitative copper accumulation scores were significantly associated with hepatic copper concentrations; however, the correlation between qualitative score and concentration obtained with digital image analysis (rs = 0.94) was higher than the correlation between qualitative score and concentration obtained with AAS (rs = 0.75) or ICP-MS (rs = 0.57). The coefficient of variation for hepatic copper concentrations obtained with digital image analysis was significantly higher for dogs with higher hepatic copper concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that spectroscopic-spectrometric analysis of hepatic biopsy specimens commonly underestimated the concentration obtained by digital image analysis of rhodanine-stained sections.

Congenital erythropoietic protoporphyria and protoporphyric hepatopathy in a dog.

CASE DESCRIPTION: A 6-month-old sexually intact male Clumber Spaniel was evaluated because of small stature, recurrent dermatitis of the head, and progressive pigmentary hepatopathy. CLINICAL FINDINGS: Clinicopathologic findings included nonanemic hypochromic microcytosis, hypocholesterolemia, persistently high serum liver enzyme activities, and anicteric hyperbilirubinemia. Histologic examination of liver biopsy specimens collected when the dog was 6 months and 2 years of age revealed expansion and bridging of portal tracts, occasional centrilobular parenchymal collapse, scattered lymphoplasmacytic infiltrates, and dark red to brown pigment within large aggregates of macrophages, engorged bile canaliculi, and hepatocytes. The pigment failed to stain for the presence of iron, copper, bile, and glycoprotein and, when examined with polarized microscopy, emitted a yellow to green birefringence with occasional Maltese cross configurations. Further analyses confirmed marked porphyrin accumulation in blood, urine, feces, and liver tissue; protoporphyrin accumulation in RBCs and liver tissue; and a signature porphyrin profile and fluorescence peak consistent with erythropoietic protoporphyria. Advanced protoporphyric hepatopathy was diagnosed. The chronic dermatopathy was presumed to reflect protoporphyric photosensitivity. TREATMENT AND OUTCOME: Management was focused on avoiding conditions known to induce heme synthesis and catabolism, administrating ursodeoxycholic acid and antioxidants S-adenosylmethionine and vitamin E, and avoiding sunlight exposure. At follow-up at 4 years of age, the dog was stable without evidence of jaundice but with probable persistent erythropoietic protoporphyria-related solar dermatopathy. CLINICAL RELEVANCE: Clinical and histologic features of congenital erythropoietic protoporphyria and resultant protoporphyric hepatopathy, the diagnosis, and the successful management of a dog with these conditions over 4 years were described. Veterinarians should consider porphyric syndromes when unusual pigmentary hepatopathies are encountered.

Clinical, clinicopathologic, and hepatic histopathologic features associated with probable ketoconazole-induced liver injury in dogs: 15 cases (2015-2018).

OBJECTIVE: To characterize clinical, clinicopathologic, and hepatic histopathologic features and outcome for dogs with probable ketoconazole-induced liver injury. ANIMALS: 15 dogs with suspected ketoconazole-induced liver injury that underwent liver biopsy. PROCEDURES: Medical record data were summarized regarding signalment, clinical signs, clinicopathologic and hepatic histopathologic findings, concurrent medications, ketoconazole dose, treatment duration, and outcome. RESULTS: Median age and body weight were 8.2 years (range, 5 to 15 years) and 13.0 kg (28.6 lb; range, 8.2 to 38.0 kg [18.0 to 83.6 lb]), respectively. The most common breed was Cocker Spaniel (n = 5). All dogs received ketoconazole to treat cutaneous Malassezia infections. Median daily ketoconazole dose was 7.8 mg/kg (3.5 mg/lb; range, 4.4 to 26.0 mg/kg [2.0 to 11.8 mg/lb]), PO. Treatment duration ranged from 0.3 to 100 cumulative weeks (intermittent cyclic administration in some dogs); 6 dogs were treated for ≤ 10 days. Common clinical signs included lethargy, anorexia, and vomiting. All dogs developed high serum liver enzyme activities. Hepatic histopathologic findings included variable lobular injury, mixed inflammatory infiltrates, and conspicuous aggregates of ceroid-lipofuscin-engorged macrophages that marked regions of parenchymal damage. Five dogs developed chronic hepatitis, including 3 with pyogranulomatous inflammation. Of the 10 dogs reported to have died at last follow-up, survival time after illness onset ranged from 0.5 to 165 weeks, with 7 dogs dying of liver-related causes. CONCLUSIONS AND CLINICAL RELEVANCE: Findings for dogs with hepatotoxicosis circumstantially associated with ketoconazole treatment suggested proactive monitoring of serum liver enzyme activities is advisable before and sequentially after initiation of such treatment.

ACVIM consensus statement on the diagnosis and treatment of chronic hepatitis in dogs.

This consensus statement on chronic hepatitis (CH) in dogs is based on the expert opinion of 7 specialists with extensive experience in diagnosing, treating, and conducting clinical research in hepatology in dogs. It was generated from expert opinion and information gathered from searching of PubMed for manuscripts on CH, the Veterinary Information Network for abstracts and conference proceeding from annual meetings of the American College of Veterinary Medicine and the European College of Veterinary Medicine, and selected manuscripts from the human literature on CH. The panel recognizes that the diagnosis and treatment of CH in the dog is a complex process that requires integration of clinical presentation with clinical pathology, diagnostic imaging, and hepatic biopsy. Essential to this process is an index of suspicion for CH, knowledge of how to best collect tissue samples, access to a pathologist with experience in assessing hepatic histopathology, knowledge of reasonable medical interventions, and a strategy for monitoring treatment response and complications.

Reference limits for hepatic bile duct-to-arteriole and bile duct-to-portal tract ratios in healthy cats.

OBJECTIVE To establish reference limits for hepatic bile duct-to-arteriole ratio (BD:A) and bile duct-to-portal tract ratio (BD:PT) in healthy cats and assess whether these parameters could be used to support a diagnosis of biliary ductopenia in cats. SAMPLE Hepatic biopsy samples from healthy cats (n = 20) and cats with ductopenia (2). PROCEDURES Hepatic biopsy samples from healthy cats were used to count the number of bile ducts and hepatic arterioles in 20 portal tracts for each cat. Mean BD:A and mean BD:PT for each cat were calculated, and these values were used to determine reference limits for mean BD:A and mean BD:PT. Results of histologic evaluation, including immunohistochemical staining in some instances, were compared for healthy cats versus cats with ductopenia. RESULTS Of the 400 portal tracts from healthy cats, 382 (95.5%) and 396 (99.0%) had BD:A and BD:PT, respectively, ≥ 1.0, with less variability in BD:A. Mean BD:A and BD:PT were markedly lower in both cats with ductopenia, compared with values for healthy cats. However, only mean BD:A for cats with ductopenia was below the reference limit of 0.59. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that systematic evaluation of BD:A, with a lower reference limit of 0.59 to define biliary ductopenia in cats, may be a discrete and easily applied morphometric tool to enhance detection of ductopenia in cats. However, application of this ratio required evaluation of ≥ 20 portal tracts with cross-sectioned portal elements to determine a mean BD:A value.

Characterization of aminoaciduria and hypoaminoacidemia in dogs with hepatocutaneous syndrome.

OBJECTIVE To characterize aminoaciduria and plasma amino acid concentrations in dogs with hepatocutaneous syndrome (HCS). ANIMALS 20 client-owned dogs of various breeds and ages. PROCEDURES HCS was definitively diagnosed on the basis of liver biopsy specimens (n = 12), gross and histologic appearance of skin lesions (4), and examination of skin and liver biopsy specimens (2) and presumptively diagnosed on the basis of cutaneous lesions with compatible clinicopathologic and hepatic ultrasonographic (honeycomb or Swiss cheese pattern) findings (2). Amino acid concentrations in heparinized plasma and urine (samples obtained within 8 hours of each other) were measured by use of ion exchange chromatography. Urine creatinine concentration was used to normalize urine amino acid concentrations. Plasma amino acid values were compared relative to mean reference values; urine-corrected amino acid values were compared relative to maximal reference values. RESULTS All dogs had generalized hypoaminoacidemia, with numerous amino acid concentrations < 50% of mean reference values. The most consistent and severe abnormalities involved glutamine, proline, cysteine, and hydroxyproline, and all dogs had marked lysinuria. Urine amino acids exceeding maximum reference values (value > 1.0) included lysine, 1-methylhistidine, and proline. CONCLUSIONS AND CLINICAL RELEVANCE Hypoaminoacidemia in dogs with HCS prominently involved amino acids associated with the urea cycle and synthesis of glutathione and collagen. Marked lysinuria and prolinuria implicated dysfunction of specific amino acid transporters and wasting of amino acids essential for collagen synthesis. These findings may provide a means for tailoring nutritional support and for facilitating HCS diagnosis.

Hepatocutaneous syndrome in Shih Tzus: 31 cases (1996-2014).

OBJECTIVE: To characterize findings in Shih Tzus with progressive superficial necrolytic dermatitis and degenerative vacuolar hepatopathy consistent with hepatocutaneous syndrome. DESIGN: Retrospective case series. ANIMALS: 31 Shih Tzus. PROCEDURES: Medical records were reviewed to obtain information on signalment, history, treatment, outcome, and results of clinicopathologic testing, abdominal ultrasonography, and histologic examination of skin and liver specimens. A pedigree analysis was performed. RESULTS: There were 16 males and 15 females. Median age at the time of diagnosis was 8 years (range, 5 to 14 years). Common clinical signs included lethargy, inappetence, weight loss, and lameness. Twenty-five dogs had cutaneous lesions consistent with hepatocutaneous syndrome; the remaining 6 initially only had hepatic abnormalities, but 3 of the 6 subsequently developed cutaneous lesions. Common clinicopathologic abnormalities included microcytosis (15/24 [63%] dogs) and high serum alkaline phosphatase activity (24/24 [100%] dogs). Hepatic ultrasonographic findings included a hyperechoic or heteroechoic appearance to the parenchyma with innumerable hypoechoic nodules. Histologic hepatic lesions consisted of degenerative vacuolar (glycogen and lipid) hepatopathy associated with minimally fibrotic to nonfibrotic, noninflammatory, proliferative nodules. Pedigree analysis confirmed a common ancestry in 12 of 18 dogs. Median survival time was 3 months (range, 1 to 36 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that HCS may have a heritable component in Shih Tzus, although the condition may also be identified in Shih Tzus without affected relatives. Clinical, clinicopathologic, ultrasonographic, and histologic abnormalities in affected Shih Tzus were similar to those previously reported for dogs of other breeds with HCS.

Complex disease and phenotype mapping in the domestic dog.

The domestic dog is becoming an increasingly valuable model species in medical genetics, showing particular promise to advance our understanding of cancer and orthopaedic disease. Here we undertake the largest canine genome-wide association study to date, with a panel of over 4,200 dogs genotyped at 180,000 markers, to accelerate mapping efforts. For complex diseases, we identify loci significantly associated with hip dysplasia, elbow dysplasia, idiopathic epilepsy, lymphoma, mast cell tumour and granulomatous colitis; for morphological traits, we report three novel quantitative trait loci that influence body size and one that influences fur length and shedding. Using simulation studies, we show that modestly larger sample sizes and denser marker sets will be sufficient to identify most moderate- to large-effect complex disease loci. This proposed design will enable efficient mapping of canine complex diseases, most of which have human homologues, using far fewer samples than required in human studies.

Adverse interaction between colchicine and ketoconazole in a Chinese shar pei.

A Chinese shar pei with a 2 yr history of episodic fever, lethargy, and shifting lameness was presumptively diagnosed with familial shar pei fever but had never been treated for the syndrome. After being presented for a superficial pyoderma with possible dermatophyte coinfection, treatment with a cephalosporin and ketoconazole were prescribed. One wk later, colchicine was initiated for familial shar pei fever using cautious dose escalation. Nevertheless, gastrointestinal toxicity, skeletal muscle myopathy, and hepatotoxicity developed within 2 wk. Abrupt resolution of gastrointestinal toxicity and myopathy followed drug withdrawal. However, escalating liver enzyme activity and hyperbilirubinemia led to liver biopsy to rule out an antecedent hepatopathy. Biopsy characterized canalicular cholestasis and colchicine-associated metaphase arrest and ring mitoses reflecting repression of mitotic spindle formation. Signs of illness completely resolved 3 mo after drug discontinuation. Although avoidable adverse interactions between ketoconazole and drugs reliant on cytochrome oxidase biotransformation and/or drug efflux mediated by multiple drug-resistant transporters are well documented in humans, these are rarely reported in veterinary patients. This case exemplifies an important and avoidable ketoconazole/colchicine drug interaction from which the patient completely recovered. The dog tested negative for the canine MDR1 loss of function mutation that also might potentiate colchicine toxicity.

Clinical features of progressive vacuolar hepatopathy in Scottish Terriers with and without hepatocellular carcinoma: 114 cases (1980-2013).

OBJECTIVE: To characterize signalment, clinical features, clinicopathologic variables, hepatic ultrasonographic characteristics, endocrinologic profiles, treatment response, and age at death of Scottish Terriers with progressive vacuolar hepatopathy (VH) with or without hepatocellular carcinoma (HCC). DESIGN: Retrospective case series. ANIMALS: 114 Scottish Terriers with progressive VH. PROCEDURES: Electronic databases from 1980 to 2013 were searched for adult (age > 1 year) Scottish Terriers with histopathologic diagnoses of diffuse glycogen-like VH. Available sections of liver specimens were histologically reevaluated to confirm diffuse VH with or without HCC; 8 dogs with HCC only had neoplastic tissue available. Physical examination, clinicopathologic, treatment, and survival data were obtained. RESULTS: 39 of 114 (34%) dogs with VH had HCC detected at surgery or necropsy or by abdominal ultrasonography. Histologic findings indicated that HCC was seemingly preceded by dysplastic hepatocellular foci. No significant differences were found in clinicopathologic variables or age at death between VH-affected dogs with or without HCC. Fifteen of 26 (58%) dogs with high hepatic copper concentrations had histologic features consistent with copper-associated hepatopathy. Although signs consistent with hyperadrenocorticism were observed in 40% (46/114) of dogs, definitive diagnosis was inconsistently confirmed. Assessment of adrenal sex hormone concentrations before and after ACTH administration identified high progesterone and androstenedione concentrations in 88% (22/25) and 80% (20/25) of tested dogs, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that VH in Scottish Terriers may be linked to adrenal steroidogenesis and a predisposition to HCC. In dogs with VH, frequent serum biochemical analysis and ultrasonographic surveillance for early tumor detection are recommended.

Presumed primary and secondary hepatic copper accumulation in cats.

OBJECTIVE: To determine signalments, clinical features, clinicopathologic variables, imaging findings, treatments, and survival time of cats with presumed primary copper-associated hepatopathy (PCH) and to determine quantitative measures and histologic characteristics of the accumulation and distribution of copper in liver samples of cats with presumed PCH, extrahepatic bile duct obstruction, chronic nonsuppurative cholangitis-cholangiohepatitis, and miscellaneous other hepatobiliary disorders and liver samples of cats without hepatobiliary disease. DESIGN: Retrospective cross-sectional study. ANIMALS: 100 cats with hepatobiliary disease (PCH [n = 11], extrahepatic bile duct obstruction [14], cholangitis-cholangiohepatitis [37], and miscellaneous hepatobiliary disorders [38]) and 14 cats without hepatobiliary disease. PROCEDURES: From 1980 to 2013, cats with and without hepatobiliary disease confirmed by liver biopsy and measurement of hepatic copper concentrations were identified. Clinical, clinicopathologic, and imaging data were compared between cats with and without PCH. RESULTS: Cats with PCH were typically young (median age, 2.0 years); clinicopathologic and imaging characteristics were similar to those of cats with other liver disorders. Copper-specific staining patterns and quantification of copper in liver samples confirmed PCH (on the basis of detection of > 700 µg/g of liver sample dry weight). Six cats with PCH underwent successful treatment with chelation (penicillamine; n = 5), antioxidants (5), low doses of elemental zinc (2), and feeding of hepatic support or high-protein, low-carbohydrate diets, and other hepatic support treatments. One cat that received penicillamine developed hemolytic anemia, which resolved after discontinuation of administration. Three cats with high hepatic copper concentrations developed hepatocellular neoplasia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that copper accumulates in livers of cats as primary and secondary processes. Long-term management of cats with PCH was possible.

Digital image analysis of rhodanine-stained liver biopsy specimens for calculation of hepatic copper concentrations in dogs.

OBJECTIVE: To evaluate the accuracy of digitally scanned rhodanine-stained liver biopsy specimens for determination of hepatic copper concentration and compare results with qualitatively assigned histologic copper scores in dogs. SAMPLE: 353 liver biopsy specimens from dogs. PROCEDURES: Specimens (n = 139) with quantified copper concentration ranging from 93 to 6,900 µg/g were allocated to group 1 (< 400 µg/g [37]), group 2 (401 to 1,000 µg/g [27]), group 3 (1,001 to 2,000 µg/g [34]), and group 4 (> 2,001 µg/g [41]); stained with rhodanine; and digitally scanned and analyzed with a proprietary positive pixel algorithm. Measured versus calculated copper concentrations were compared, and limits of agreement determined. Influence of nodular remodeling, fibrosis, or parenchymal loss on copper concentration was determined by digitally analyzing selected regions in 17 specimens. After method validation, 214 additional liver specimens underwent digital scanning for copper concentration determination. All sections (n = 353) were then independently scored by 2 naive evaluators with a qualitative scoring schema. Agreement between assigned scores and between assigned scores and tissue copper concentrations was determined. RESULTS: Linear regression was used to develop a formula for calculating hepatic copper concentration ≥ 400 µg/g from scanned sections. Copper concentrations in unremodeled specimens were significantly higher than in remodeled specimens. Qualitative scores widely overlapped among quantitative copper concentration groups. CONCLUSIONS AND CLINICAL RELEVANCE: Calculated copper concentrations determined by means of digital scanning of rhodanine-stained liver sections were highly correlated with measured values and more accurate than qualitative copper scores, which should improve diagnostic usefulness of hepatic copper concentrations and assessments in sequential biopsy specimens.

Influence of treatment with ultralow-dose aspirin on platelet aggregation as measured by whole blood impedance aggregometry and platelet P-selectin expression in clinically normal dogs.

OBJECTIVE: To evaluate the influence of treatment with ultralow-dose aspirin (ULDAsp) on platelet aggregation, P-selectin (CD62P) expression, and formation of platelet-leukocyte aggregates in clinically normal dogs. ANIMALS: 18 clinically normal dogs. PROCEDURES: Studies were conducted before and 24 hours after ULDAsp administration (0.5 mg/kg, PO, q 24 h, for 2 days). Whole blood impedance aggregometry for the assessment of platelet function was performed with sodium citrate-anticoagulated blood and aggregation agonists (ADP at 20, 10, and 5 µmol/L; collagen at 10, 5, and 2 µg/mL). Onset, maximum response, and rate of platelet aggregation were recorded. Flow cytometric assays were configured to detect thrombin-induced CD62P expression and platelet-leukocyte aggregates in EDTA-anticoagulated whole blood. Externalized platelet CD62P and constitutive CD61 (GPIIIa) were labeled with antibodies conjugated to phycoerythrin (PE) and fluorescein isothiocyanate (FITC), respectively. Red blood cell-lysed paraformaldehyde-fixed EDTA-anticoagulated whole blood was dual labeled with CD61-FITC and a panleukocyte antibody (CD18-PE) to characterize platelet-leukocyte aggregates. RESULTS: ULDAsp significantly delayed platelet aggregation onset with ADP at 20 µmol/L by 54% to 104%, attenuated maximum aggregation with various concentrations of ADP and collagen by ≥ 41%, and slowed aggregation rate with the highest ADP and collagen concentrations by ≥ 39%. Depending on the parameter tested, up to 30% of dogs failed to have an ULDAsp effect. Thrombin stimulation significantly increased CD62P expression in platelets and platelet-leukocyte aggregates, but ULDAsp did not alter basal or thrombin-stimulated CD62P expression. CONCLUSIONS AND CLINICAL RELEVANCE: ULDAsp treatment of clinically normal dogs impaired platelet aggregation in most dogs, but did not influence CD62P platelet membrane expression.