Prevalence and risk factors of hepatic lipid changes in bearded dragons (Pogona vitticeps)

Abstract

Hepatic lipidosis is a common disease of captive bearded dragons ( Pogona vitticeps). Diagnosis, prevention, and treatment of this condition are challenging, as there is minimal information in the literature. Our study determined the prevalence and epidemiological risk factors associated with the grade and severity of hepatic lipid changes in bearded dragons submitted for necropsy in 2 North American institutions. A total of 571 postmortem cases were retrieved, and from each pathology report the demographic data (age, sex) and the list of final diagnoses were extracted. For each case diagnosed with hepatic lipidosis, the archived sections of liver were reviewed and the severity of lipid change was stratified using a standardized histologic grading system. Descriptive statistics were used to estimate the prevalence of each grade and severity class. Associations between grade and severity, as well as demographic data and concurrent diseases, were explored using ordinal logistic regression analysis. On multiple logistic models, the occurrence of infectious disease and neoplasia was associated with decreased grade and severity of hepatic lipid changes, while the female sex and adult age were associated with an increased grade and severity. None of the other variables were significantly associated with hepatic lipid changes. These results suggest that reproductively active females and adult bearded dragons are predisposed to increasing hepatic lipid changes, while those with an underlying disease process have reduced hepatic lipid accumulation and changes, possibly due to increased fat catabolism. Data in this study can serve to benchmark the prevalence of hepatic lipidosis in bearded dragons and allow further investigations.

Association of plasma metabolites and diagnostic imaging findings with hepatic lipidosis in bearded dragons (Pogona vitticeps) and effects of gemfibrozil therapy

“…Hepatic lipidosis, also known as fatty liver disease or steatosis, is a commonly reported necropsy finding in pet bearded dragons (Pogona vitticeps) [1]. A prevalence of 27.3% (156/571) has been reported for moderate to severe hepatic lipid changes in bearded dragons presented for necropsy at two North American pathology laboratories [1].…”

“…Hepatic lipidosis, also known as fatty liver disease or steatosis, is a commonly reported necropsy finding in pet bearded dragons (Pogona vitticeps) [1]. A prevalence of 27.3% (156/571) has been reported for moderate to severe hepatic lipid changes in bearded dragons presented for necropsy at two North American pathology laboratories [1]. The disease process involves a progressive accumulation of triacylglycerol in the hepatocytes resulting in disruption of microanatomy, which leads to impaired hepatic metabolism and function, as well as dyslipidemia [2][3][4][5][6].…”

“…Hepatic lipidosis is also suspected in clinical cases of bearded dragons that present with non-specific clinical signs including anorexia, lethargy, and weight loss; ultimately progressing to liver failure and death [3,[7][8][9]. Retrospective data has indicated that age (adult) and sex (female) are risk factors for increased grade and class of hepatic lipid changes [1]. Infectious disease and neoplasia were found to be strong negative predictors for hepatic lipid accumulation and changes [1].…”

“…Retrospective data has indicated that age (adult) and sex (female) are risk factors for increased grade and class of hepatic lipid changes [1]. Infectious disease and neoplasia were found to be strong negative predictors for hepatic lipid accumulation and changes [1].…”

“…Despite the common diagnosis of hepatic lipidosis in bearded dragons [1], there is a large knowledge gap regarding its pathophysiology, diagnostic testing, biomarkers, and treatment. The objectives of this study were to: better understand the metabolic derangement associated with hepatic lipidosis in a cohort of bearded dragons with spontaneous disease; to identify potential novel plasma biomarkers that could be used for non-invasive diagnosis and monitoring of hepatic lipidosis using quantitative (targeted) metabolomics and lipidomics; to validate CT as a non-invasive diagnostic tool for hepatic lipidosis in bearded dragons; and to assess gemfibrozil's efficacy on improving liver density on imaging, blood biomarkers, and hepatic fat content on histology.…”