A Comparison of Liver Sampling Techniques in Dogs

198

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.

Section: Biopsy Acquisitionmentioning

confidence: 99%

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

Webster

Cullen

Penninck

et al. 2019

198

“…Diagnostic accuracy and portal triad numbers obtained using less invasive liver biopsy sample methods have been tested. To date, the smallest sampling method that has equivalent histologic agreement (66%) with gold‐standard large wedge biopsy is the 14‐gauge (14 Ga) needle, when compared to larger sampling methods (5 mm cup and 8 mm punch biopsy instruments) . An18 Ga needle biopsy is a less accurate diagnostic method with a 49% agreement with gold‐standard wedge biopsy for the full spectrum of histologic diagnoses .…”

Section: Introductionmentioning

confidence: 99%

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

Kimbrell

Milovancev

Olsen

et al. 2018

BackgroundDiagnostic accuracy of the 3 mm laparoscopic cup biopsy forceps for collection of tissue samples from canine livers is unproven.Hypotheses/ObjectivesCompare 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.AnimalsTwenty‐one client‐owned dogs undergoing necropsy.MethodsProspective 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.ResultsThere 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 ImportanceDespite yielding smaller sample sizes, the 3 mm laparoscopic cup biopsy has a similar level of histologic diagnostic accuracy to the 5 mm instrument.

“…In dogs undergoing necropsy, histological diagnoses were in agreement with those from wedge samples in 66% of needle samples, 60% of cup samples, and 69% of punch samples, but these proportions were not significantly different from each other. The authors of this study concluded that the histopathologic interpretation of a liver biopsy specimen in the dog is unlikely to vary whether it contains at least 3–12 portal triads . However, it is recommended that pathologists be presented with specimens containing at least 11 portal triads .…”

Section: Diagnosis Of Hepatic Fibrosismentioning

confidence: 96%

Hepatic Fibrosis in Dogs

Eulenberg

Lidbury

2017

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.