A comparison of liver sampling techniques in dogs

Comparing 3 mm and 5 mm laparoscopic liver biopsy samples in dogs

OBJECTIVE

To determine whether 3 mm cup biopsy forceps (CBF) provide equivalent diagnostic samples to 5 mm CBF for histopathologic diagnosis, bacterial culture, and copper quantification.

STUDY DESIGN

Clinical prospective study.

ANIMALS

Ten client-owned dogs, presenting for laparoscopic liver biopsy (LLB).

METHODS

Dogs underwent LLB, and paired samples were collected using 3 and 5 mm CBF. Portal triad and hepatic lobule counts, crush and fragmentation artifacts, copper concentration, bacterial culture results, and agreement on histopathologic diagnosis were compared.

RESULTS

Both CBF sizes allowed for easy sample collection and resulted in minimal hemorrhage. An average of 12.13 (confidence limit (CL): 9.4-14.9) and 17.84 (CL: 15.1-20.6) portal triads were obtained using a 3 and 5 mm CBF, respectively (p = .0003). A portal triad count of 11 or more was achieved in 73.3% of the 3 mm and 93.3% of the 5 mm samples. Gwets AC1 coefficient showed a high level of agreement (0.8) for overall histopathologic diagnosis (p < .0001). The 3 mm CBF crush scores were higher (median of the differences: -1; range: -1 to 1) (p = .035). There was no difference in fragmentation scores (p = .935).

CONCLUSION

The 3 mm CBF yielded smaller samples in terms of size and portal triad count compared with the 5 mm CBF. However, the portal triad count was sufficient in a majority of samples and histologic agreement with the 5 mm CBF was excellent.

CLINICAL SIGNIFICANCE

In dogs, a 3 mm CBF yields adequate samples for histopathologic interpretation, copper quantification, and bacterial culture.

Comparison of the diagnostic yield of 3 and 5 mm laparoscopic liver biopsy forceps in cats

OBJECTIVE

To determine whether 3 and 5 mm laparoscopic cup biopsy forceps provide samples of equivalent diagnostic quality in cats.

STUDY DESIGN

Experimental study.

ANIMALS

Twelve colony cats undergoing a concurrent nutrition study.

METHODS

Two biopsy forceps (3 and 5 mm) and three biopsy techniques (twist, pull, and twist + pull) were used to collect 68 laparoscopic liver samples. Biopsies were performed consecutively with the 3 and 5 mm biopsy sites adjacent to each other. Data analyzed included the number of portal triads and hepatic lobules, tissue crush and fragmentation, overall sample area (mm2 ), sample weight, and agreement regarding morphologic diagnosis.

RESULTS

The 5 mm forceps provided more hepatic lobules, portal triads, and a larger tissue weight and histologic area (mm2 ) (p < .01). The twist and pull techniques provide more hepatic lobules and portal triads compared to the twist + pull technique while the twist + pull technique resulted in greater tissue crush compared to the twist technique (p = .0097). There was good agreement for morphological diagnosis between the 3 and 5 mm samples using the twist + pull technique but not for the twist or pull techniques.

CONCLUSION

Liver samples can be safely collected with 3 or 5 mm laparoscopic biopsy forceps and provide sufficient tissue for histopathology analysis in cats, with minimal artifact. The diagnostic accuracy of 3 mm samples remains unknown.

CLINICAL SIGNIFICANCE

Although 3 mm laparoscopic cup biopsy forceps provided samples of sufficient diagnostic quality for histopathologic interpretation in cats, further studies are required to assess their diagnostic accuracy.

Needle tract seeding and malignant transformation of hepatocellular adenoma into well-differentiated hepatocellular carcinoma in a dog

An 11-year-old neutered female Golden Retriever was referred for investigation of marked increases in liver enzyme activities. Abdominal ultrasound revealed a large pedunculated liver mass. Diagnosis of hepatocellular adenoma (HCA) was made when the mass was excised after a first unsuccessful attempt through ultrasound-guided core-needle biopsy. One and a half years after presentation, a nodule embedded between muscles of the abdominal wall appeared. The mass was first diagnosed as a well-differentiated hepatocellular carcinoma (HCC) through cytologic examination, which was later confirmed with histopathology. Ki 67 immunostaining of the abdominal wall nodule showed an increased immunoreactivity compared with the liver mass. Therefore, the present case documents the first needle-tract seeding of a hepatocellular epithelial tumor with possible malignant transformation of HCA into a well-differentiated HCC in a dog.

Patterns of Lymphocytic Infiltrates Can Differentiate Feline Hepatic Lymphoma from Lymphocytic Portal Hepatitis

Hepatic lymphoma is poorly characterized in cats and differentiating between inflammation and lymphomas is often difficult. The diagnosis of hepatic lymphoma in humans relies on recognition of specific patterns of lymphocytic infiltrates and clonality testing of antigen receptors. Herein, we defined similar patterns of lymphocytic infiltrates in hepatic biopsies of cats and correlated them with clonality to determine which patterns are predictive of lymphoma. A retrospective study was performed on surgical biopsies from 44 cats. The immunophenotype was characterized using CD3 and CD20 on all 44 samples. All 44 samples were tested using PCR for T-cell receptor gamma-gene rearrangements. PCR for immunoglobulin heavy chain gene rearrangements was performed on 24 of these cats. Four patterns of lymphocytic infiltrates were characterized: (1) tightly periportal, (2) periportal and centrilobular, (3) nodular, and (4) periportal with sinusoidal extension. Other histomorphologic features (fibrosis, biliary hyperplasia, bile ductopenia, bile duct targeting, hepatic hematopoiesis, lipogranulomas, lymphonodular aggregates, other inflammatory cells) were also evaluated. The sensitivity and specificity of the lymphocytic patterns to diagnose lymphomas were determined using Bayesian Hui-Walter analysis (BLCM) against clonality results. Lymphocytic patterns 2, 3, and 4 accurately diagnosed hepatic lymphomas with a sensitivity and specificity of 82% (CI 95%: 0.65, 0.96) and 77% (CI 95%: 0.54, 1.00), respectively. None of the other microscopic features evaluated were predictive of a lymphoma or inflammation. Our study identified specific patterns of lymphocytic infiltration that differentiate feline hepatic lymphoma from inflammation while other histologic features were not associated with an accurate diagnosis.

Laparoscopic twist technique has the best overall artifact profile when comparing three laparoscopic hepatic cup biopsy techniques for dogs

OBJECTIVE

To determine the difference in histologic artifacts and morphologic diagnosis among 3 laparoscopic cup biopsy forceps techniques and wedge hepatic samples.

ANIMALS

Cadavers of 20 client-owned dogs following euthanasia for unrelated reasons between January 3 and July 29, 2021.

PROCEDURES

Four biopsy techniques were performed from the margin of 3 liver lobes/dog. Laparoscopic techniques used 5-mm cup biopsy forceps to obtain biopsy samples by pulling the forceps forcefully caudally to free a sample (the PULL technique), rotating the forceps 360° in 1 direction until freed (the TWST technique), or pulling the forceps through a 5-mm cannula to remove the sample (the CAN technique); wedge biopsy samples served as the control (CON). Data collected included sample weight, histologic features, diagnosis, and artifact characterization. Gwet AC1 or intraclass correlation coefficients (ICCs) were calculated to detect agreement among techniques.

RESULTS

Sample weights for CON and TWST were significantly larger (P < .001 and P = .035, respectively) than for PULL and CAN. There was excellent agreement among all techniques for most diagnostic features (Gwet AC1, 0.93 to 1). The TWST technique resulted in the best overall artifact profile for laparoscopic techniques, with 90% of samples (54/60) having crisp edges and 65% of samples (39/60) having no or mild tearing. The agreement was moderate to good (ICC, 0.73 for edges and 0.76 for tearing) among all cup biopsy forceps techniques.

CLINICAL RELEVANCE

The TWST technique resulted in the largest sample and had the fewest artifacts, supporting its continued use during laparoscopic procedures.

Comparative Oncology: Management of Hepatic Neoplasia in Humans and Dogs

Primary hepatic neoplasia is uncommonly reported in dogs. Hepatocellular carcinoma (HCC) is the most frequent neoplasia identified in dogs and considerable effort has been committed towards identifying definitive and palliative treatment options. HCC is well recognized in humans as a sequelae of liver disease such as hepatitis or cirrhosis, while in dogs a similar link has failed to be fully elucidated. Management of HCC in people may be curative or palliative dependent on staging and transplant eligibility. Despite differences in etiology, there is substantial similarity between treatment options for liver neoplasia in human and veterinary medicine. The below summary provides a comparative discussion regarding hepatic neoplasia in dogs and people with a specific focus on HCC. Diagnosis as well as descriptions of the myriad treatment options will be reviewed.

Approach to the Diagnosis of Hepatocutaneous Syndrome in Dogs: A Retrospective Study and Literature Review

Superficial necrolytic dermatitis (SND) is a rare and often fatal disease in dogs that has been associated with pancreatic neuroendocrine neoplasia (SND/EN) and hepatocutaneous syndrome (SND/HCS). Although various combinations of diagnostics have been used to differentiate these two causes of SND, there are currently no data on which combination would enable the most timely and noninvasive way to diagnose HCS. Medical records were reviewed retrospectively (2004-2018) for dogs with SND/HCS (n = 24) and SND/EN (n = 1). These data were compared with cases found by review of the literature of dogs with SND/HCS (n = 105) and SND/EN (n = 13). The most consistent findings with SND were dermatological lesions affecting paw pads or mucocutaneous junctions (143/143, 100%) and marked plasma hypoaminoacidemia (58/58, 100%). On ultrasound, a honeycomb liver was seen in 62/63 (98%) dogs with SND/HCS but none with SND/EN. Six out of 23 (26%) dogs in the retrospective study with SND/HCS had marked keratinocyte apoptosis, a finding that was associated with diabetes mellitus. This study suggests that in dogs with characteristic skin lesions, an amino acid profile permits a noninvasive diagnosis of SND. An abdominal ultrasound can then assist in the differentiation of SND/HCS and SND/EN.

Hemorrhage and complications associated with percutaneous ultrasound guided liver biopsy in dogs

BACKGROUND

Liver biopsy is often necessary to obtain a diagnosis in dogs with hepatobiliary disease. Hemorrhage after biopsy is a concern.

OBJECTIVE

To describe the extent of hemorrhage and incidence of complications after percutaneous ultrasound guided liver biopsy (PUGLB) in dogs and to examine risk factors for hemorrhage or complications.

ANIMALS

One hundred two client owned dogs with suspected hepatobiliary disease that underwent PUGLB.

METHODS

Medical records were retrospectively reviewed. Using human guidelines, major hemorrhage was defined as an absolute decrease in the PCV (ΔPCV) ≥ 6%. Complications were defined separately as clinically relevant physiologic compromise that necessitated intervention or death. The relationship between ΔPCV and the occurrence of complications and the initial PCV, coagulation variables, serum activity of liver-derived enzymes, serum bilirubin concentration, number of biopsies, biopsy needle gauge, radiologist experience, histological diagnosis, and ultrasound variables were compared.

RESULTS

Before PUGLB, most aberrations in coagulation variables were mild. After biopsy a decrease in PCV occurred in 87/102 (85.3%) dogs. The mean ΔPCV was -7.2% ± 4.5%. Major hemorrhage occurred in 43/102 (42.2%) dogs and complications in 2/102 (1.9%). ΔPCV was significantly positively correlated with PCV before biopsy (r = .47, P = .004). There was no correlation between ΔPCV or complications with any of the variables examined.

CONCLUSION AND CLINICAL IMPORTANCE

Percutaneous ultrasound guided liver biopsy in the population of dogs in the current study, with normal or mild abnormalities in coagulation, results in a high incidence of clinically silent, major hemorrhage (42.5%), but few complications (1.9%).

A descriptive study of the histopathologic and biochemical liver test abnormalities in dogs with liver disease in Thailand

The present study describes the serum biochemical alterations and histopathological abnormalities in the liver tissue of dogs with liver disease. A survey of hepatic lesions was conducted using ultrasound-guided percutaneous needle biopsies. The hematologic and biochemical changes in dogs with liver lesions were recorded. Chronic hepatitis was the most common liver histopathologic finding (37.9%). Other common findings included liver fibrosis (19.5%), vacuolar hepatopathy (10.3%), cholangiohepatitis (9.2%), hepatocellular carcinoma (4.6%), cholangitis (3.4%), cholangiocarcinoma (2.3%), and congestive hepatopathy (2.3%). Greater than 2-fold elevation of serum alanine aminotransferase (ALT) was a useful indicator, with a sensitivity of 40% to 65% for diagnosing all liver pathologies. Greater than 2-fold elevation of serum alkaline phosphatase (ALP) without significant elevation of ALT was useful for diagnosing liver diseases affected by inflammatory or regressive changes (sensitivity of 40% to 50%). Elevation of ALT, ALP, or a combination of ALT and ALP had a high sensitivity of up to 90% for identifying dogs with liver pathology. Hepatic injury and cholestasis enzymes should be interpreted together with patient history, clinical signs, and liver ultrasonographic appearance before performing a liver biopsy.

Canine copper-associated hepatitis: A retrospective study of 17 clinical cases

Background:

Copper-associated hepatitis (CAH) is a well-documented chronic hepatic disease in dogs. In some breeds, the disease results from an inherited defect in copper metabolism. In others, it is unclear whether its acummulation is a primary or secondary condition. Reports of copper accumulation in dog breeds that are not genetically predisposed are increasing.

Aim:

To describe the epidemiology, clinical and laboratory findings, liver biopsy techniques, and treatment response in dogs with CAH.

Methods:

A retrospective study was performed, drawing upon medical records from CAH dogs at a Veterinary Referral Hospital in Paris, France. The diagnosis of CAH had been confirmed in these patients by positive rhodanine staining of hepatic tissue obtained through biopsy. Medical records were mined for the following data: age at presentation, sex, breed, chief presenting complaints, abdominal ultrasound (US) findings, and rhodanine staining pattern.

Results:

A total of 17 dogs were included in the study. Median age at presentation was 8-year old (4–11). No sex predisposition was found. Terriers (4/17) and German Shepherd Dogs (GSD, 3/17) were overrepresented. American Staffordshire Terriers and Beauceron had not previously appeared in case reports on CAH; two of each breed were identified in this study. Clinical signs of affected dogs were non-specific. An incidental identification of increased liver-enzymes was observed in 5/17 dogs. A heterogeneous, mottled liver was frequently described (5/17) on abdominal US. Liver biopsies were performed by US-guided percutaneous approach in 10/17 dogs, laparoscopy and laparotomy in 6/17 and 1/17, respectively. The rhodanine staining pattern was centrilobular (zone 3) in 8/17 dogs and periportal (zone 1) in 3/17 dogs. The pattern was considered multifocal in 6/17 dogs.

Conclusion:

Increased liver enzymes may be the only clinical finding in dogs with copper-associated hepatitis, reflecting the silent progression of this disease. Centrilobular pattern of rhodanine staining was observed in the majority of cases suggesting the primary condition of the disease. Results of this study are consistent with the current literature, which reports that terriers and GSD are predisposed to CAH. This is the first description of CAH in Beauceron and American Staffordshire Terrier dogs.

Retrospective evaluation of cyclosporine in the treatment of presumed idiopathic chronic hepatitis in dogs

Background

The etiology of idiopathic chronic hepatitis (ICH) in dogs is poorly understood, but evidence supports an immune‐mediated pathogenesis in some dogs.

Objectives

To describe a case series of dogs with presumed ICH treated with cyclosporine (CsA) with or without concurrent medications and to document the incidence of biochemical remission and factors associated with failure to attain remission.

Animals

Forty‐eight client‐owned dogs diagnosed with presumed ICH, treatment of which included CsA.

Methods

Two‐institution, retrospective case series of dogs between 2010 and 2017. All dogs were treated with CsA with or without concurrent medications for ≥2 weeks. Data were collected from medical records.

Results

Biochemical remission (<1.1 times the upper limit of normal for alanine aminotransferase activity) was attained in 79% of dogs (38/48). Median dose of CsA at remission was 7.9 mg/kg/d (range, 2.5‐12.7 mg/kg/d) and median time to remission was 2.5 months (range, 0.75‐18 months). Concurrent hepatoprotectant treatment was not associated with likelihood of remission. Clinical score, ascites, hypoalbuminemia, hyperbilirubinemia, prolonged coagulation times, dose, and duration of treatment were not associated with the probability of remission or time to remission. Common adverse effects of CsA were gastrointestinal signs in 38% (18/48) and gingival hyperplasia in 25% (12/48) of treated dogs.

Conclusion and Clinical Importance

A treatment regimen including CsA and frequent hepatoprotectant use resulted in biochemical remission of ICH in most dogs. None of the evaluated factors, including hepatoprotectant use, were significantly associated with likelihood of remission. Future prospective studies are indicated to evaluate CsA monotherapy in ICH dogs.

Use of serum biomarkers in staging of canine hepatic fibrosis

Accurate staging of hepatic fibrosis (HF) is important for treatment and prognosis of canine chronic hepatitis. HF scores are used in human medicine to indirectly stage and monitor HF, decreasing the need for liver biopsy. We developed a canine HF score to screen for moderate or greater HF. We included 96 dogs in our study, including 5 healthy dogs. A liver biopsy for histologic examination and a biochemistry profile were performed on all dogs. The dogs were randomly split into a training set of 58 dogs and a validation set of 38 dogs. A HF score that included alanine aminotransferase, alkaline phosphatase, total bilirubin, potassium, and gamma-glutamyl transferase was developed in the training set. Model performance was confirmed using the internal validation set, and was similar to the performance in the training set. The overall sensitivity and specificity for the study group were 80% and 70% respectively, with an area under the curve of 0.80 (0.71-0.90). This HF score could be used for indirect diagnosis of canine HF when biochemistry panels are performed on the Konelab 30i (Thermo Scientific), using reagents as in our study. External validation is required to determine if the score is sufficiently robust to utilize biochemical results measured in other laboratories with different instruments and methodologies.

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.

Computed Tomography of Lobular Dissecting Hepatitis in a Young Golden Retriever

A 9 mo old female intact golden retriever presented for evaluation of chronic lethargy and decreased appetite. The serum biochemistry profile revealed increased liver enzymes consistent with a mixed hepatocellular and cholestatic pattern. A multiphase computed tomography angiography was performed to evaluate for a portosystemic shunt. Numerous hyperattenuating nodules were identified throughout the liver on the noncontrast-enhanced series. Histologic evaluation of percutaneous needle biopsy samples of a liver nodule showed a rare form of hepatitis called lobular dissecting hepatitis. Lobular dissecting hepatitis should be considered as a differential in young dogs with precontrast hyperattenuating hepatic nodules on noncontrast-enhanced computed tomography.

Proteomic analysis of liver tissue from dogs with chronic hepatitis

Chronic hepatitis is the most common hepatic disease in dogs. Copper accumulation is an important cause of chronic hepatitis in dogs; however, the etiology in most dogs cannot be determined. Clinical signs of chronic hepatitis are often non-specific; therefore, this disease is frequently diagnosed in an advanced stage that makes successful intervention less likely. Early diagnosis of chronic hepatitis in dogs would thus be beneficial. The identification of proteins that are differentially expressed in dogs with chronic hepatitis could contribute to the development of novel diagnostic markers for this disease and provide insight into its pathogenesis. The objective of this study was to identify novel proteins that are differentially expressed in the liver of dogs with chronic hepatitis. Hepatic tissue was collected from 8 healthy dogs during ovariohysterectomy and from 8 dogs with histologically confirmed chronic hepatitis. The proteome of the liver samples was extracted by mechanical disruption and detergent-based cell lysis and differentially labeled prior to analysis by 2-dimensional fluorescence difference gel electrophoresis. Spots with an absolute fold change value > 2.0 were selected for further analysis. Protein identification was achieved by nanoflow liquid chromatography tandem mass spectrometry. Differential expression of select proteins was validated by Western blot. Five protein spots were differentially expressed between patients with chronic hepatitis and healthy control dogs. From these 5 protein spots 11 proteins were identified. Differential expression of cytokeratin 18 and annexin 5 were confirmed by Western blot analysis. Differential protein expression was shown between dogs with chronic hepatitis and healthy control dogs. Upregulation of cytokeratin 18 in chronic hepatitis may suggest increased hepatocellular apoptosis and necrosis, whereas upregulation of annexin 5A suggests increased hepatocellular apoptosis. Further studies are needed to determine whether either protein has diagnostic utility.

Comparison of diagnostic accuracy of laparoscopic 3 mm and 5 mm cup biopsies to wedge biopsies of canine livers

BACKGROUND

Diagnostic accuracy of the 3 mm laparoscopic cup biopsy forceps for collection of tissue samples from canine livers is unproven.

HYPOTHESES/OBJECTIVES

Compare sample surface area and portal triad count between 3 mm and 5 mm laparoscopic cup biopsies and compare the histologic diagnosis obtained by each instrument to a standard necropsy wedge. The hypothesis was that more portal triads and greater sample surface area would be found with the 5 mm samples and the laparoscopic instruments would not have significantly different levels of agreement with necropsy wedge diagnosis.

ANIMALS

Twenty-one client-owned dogs undergoing necropsy.

METHODS

Prospective ex vivo study. Three samples (3 mm, 5 mm, and wedge) were taken of 2 different hepatic divisions within 24 hours of death. Morphologic diagnosis, World Small Animal Veterinary Association histologic features, surface area, and portal triad numbers were compared among the 3 samples.

RESULTS

There were significantly more portal triads (mean 21.4 versus 13.8; P < .0001) and a higher surface area (20.3 mm² versus 11.5 mm² ; P < .0001) in the 5 mm samples compared to 3 mm samples. Kappa coefficients and percent agreement for histologic diagnosis as compared to the wedge biopsy were not significantly different between the 2 instrument sizes (κ = 0.383 and 0.436, respectively; 67% and 69%, respectively).

CONCLUSIONS AND CLINICAL IMPORTANCE

Despite yielding smaller sample sizes, the 3 mm laparoscopic cup biopsy has a similar level of histologic diagnostic accuracy to the 5 mm instrument.

Hepatic Fibrosis in Dogs

Hepatic fibrosis is commonly diagnosed in dogs, often as a sequela to chronic hepatitis (CH). The development of fibrosis is a crucial event in the progression of hepatic disease that is of prognostic value. The pathophysiology of hepatic fibrosis in human patients and rodent models has been studied extensively. Although less is known about this process in dogs, evidence suggests that fibrogenic mechanisms are similar between species and that activation of hepatic stellate cells is a key step. Diagnosis and staging of hepatic fibrosis in dogs requires histopathological examination of a liver biopsy specimen. However, performing a liver biopsy is invasive and assessment of fibrotic stage is complicated by the absence of a universally accepted staging scheme in veterinary medicine. Serum biomarkers that can discriminate among different fibrosis stages are used in human patients, but such markers must be more completely evaluated in dogs before clinical use. When successful treatment of its underlying cause is feasible, reversal of hepatic fibrosis has been shown to be possible in rodent models and human patients. Reversal of fibrosis has not been well documented in dogs, but successful treatment of CH is possible. In human medicine, better understanding of the pathomechanisms of hepatic fibrosis is leading to the development of novel treatment strategies. In time, these may be applied to dogs. This article comparatively reviews the pathogenesis of hepatic fibrosis, its diagnosis, and its treatment in dogs.

Comparison of postoperative pain and inflammation reaction in dogs undergoing preventive laparoscopic-assisted and incisional gastropexy

This study compared the effects of postoperative pain and inflammation reaction after preventive laparoscopic-assisted gastropexy (LAG) and incisional gastropexy (IG) in 10 clinically normal Beagles. Surgical time, incision length, visual analog scale (VAS) score, University of Melbourne Pain Scale (UMPS) score, and plasma C-reactive protein (CRP), plasma cortisol (COR), and serum interleukin-6 (IL-6) levels were evaluated. The VAS and UMPS scores and COR and IL-6 levels were recorded at 0.5, 1, 2, 4, 8, 12, 18 and 24 hr after surgery. CRP level was recorded at 12, 24 and 48 hr after surgery. The VAS and UMPS scores showed no significant intergroup differences. Compared to IG, LAG had significantly lower surgical time (45 ± 9.91 min vs 64 ± 5.30 min; P<0.05), incision length (46 ± 8.21 mm vs 129 ± 19.49 mm; P<0.05), CRP level (12 hr after surgery; 4.58 ± 1.58 mg/dl vs 12.4 ± 1.34 mg/dl; P<0.01), and COR level (1 hr after surgery; 10.79 ± 3.07 µg/dl vs 15.9 ± 3.77 µg/dl; P<0.05). IL-6 levels showed no significant intergroup differences at any time point. However, LAG resulted in lower IL-6 levels than did IG at all postoperative time points. Neither procedure resulted in significant surgical complications. LAG produced lower surgical stress than did IG, suggesting that LAG is a safe, minimally invasive, and highly useful technique for preventing canine gastric dilatation-volvulus. Nevertheless, since this study used experimental models, its usefulness should be evaluated in future cases.

Interobserver Agreement Using Histological Scoring of the Canine Liver

Background

Grading schemes for the assessment of hepatic fibrosis and necroinflammatory activity in humans previously have been applied to dogs with chronic hepatitis. Interobserver agreement is a desirable characteristic for any histological scoring scheme.

Hypothesis/Objectives

To assess interobserver agreement associated with pathologists using a previously published histological scoring scheme to assess hepatic fibrosis and necroinflammatory activity in dogs and to compare fibrosis scores assigned to serial sections stained with hematoxylin & eosin (H&E) and picrosirius red.

Animals

Histological sections of liver from 50 dogs with variable degrees of hepatic fibrosis and necroinflammatory activity were selected from institutional tissue archives.

Methods

Six board‐certified veterinary anatomic pathologists assigned fibrosis and necroinflammatory activity scores to the histological sections. The multiuser kappa statistic was calculated to assess interobserver agreement. Fibrosis stage assigned to serial sections stained with picrosirius red and H&E was compared using the Wilcoxon signed‐rank test.

Results

Multiuser kappa statistics for assessment of fibrosis and necroinflammatory activity from H&E‐stained sections were 0.35 and 0.16, respectively. There was no difference in median fibrosis scores assigned to serial section stained with H&E and picrosirius red (P = .248).

Conclusions and Clinical Importance

There was fair interobserver agreement when pathologists assessed fibrosis and poor agreement when they assessed necroinflammatory activity. This suboptimal agreement must be taken into account by clinicians making decisions based on histology reports of the liver and in the design of studies evaluating these findings. To decrease this variability, ideally >1 pathologist should evaluate each section.

Getting the Most Out of Liver Biopsy

Histopathologic evaluation of liver biopsy specimens yields information that is not otherwise obtainable and is frequently essential for diagnosing hepatic disease. Percutaneous needle biopsy, laparoscopic biopsy, and surgical biopsy each have their own set of advantages and disadvantages. Care should be taken to ensure an adequate amount of tissue is collected for meaningful histologic evaluation. Because sampling error is a limitation of hepatic biopsy, multiple liver lobes should be biopsied. This article discusses the indications for liver biopsy, associated risks, advantages and disadvantages of different biopsy techniques, and strategies to get the most useful information possible out of this process.

Histopathologic variation between liver lobes in dogs

BACKGROUND

Biopsy of the liver evaluates a small portion of tissue, with inferences made to the entire organ. The method and number of biopsies obtained are tempered by consideration of the risks and benefits. Recommendations often include biopsy of more than one liver lobe, although the consistency of histopathology among lobes in dogs is unknown.

HYPOTHESIS/OBJECTIVES

To describe the distribution of histopathologic abnormalities between liver lobes. We hypothesized that discordant results would be evenly distributed among all liver lobes.

ANIMALS

Seventy dogs undergoing necropsy.

METHODS

Prospective study. Liver samples were obtained from all lobes. A primary diagnosis was assigned to each liver sample based on the predominant histopathologic abnormality.

RESULTS

In this population of dogs, biopsy of at least 2 liver lobes identified the predominant histologic abnormality in 98.6% of the cases. Ten (14%) of the dogs had ≤ 3 lobes in agreement and could not be assigned a predominant diagnosis. The same diagnosis was present in 6/6 lobes in 39 (56.5%) dogs, 5/6 lobes in 10 (14.5%) dogs, 4/6 lobes in 10 (14.5%) dogs, 3/6 lobes in 7 (10.1%) dogs, and 2/6 in 3 (4.3%) dogs. The number of discordant results did not differ between the liver lobes.

CONCLUSION AND CLINICAL IMPORTANCE

The likelihood of obtaining a sample that is reflective of the predominant histologic abnormality in the liver is increased when multiple liver lobes are biopsied.