Negative hepatic computed tomographic attenuation pattern in a dog with vacuolar hepatopathy and hepatic fat accumulation secondary to cushing's syndrome

Role of Glucocorticoids in Metabolic Dysfunction-Associated Steatotic Liver Disease

PURPOSE OF THE REVIEW

To summarize published data on the association between glucocorticoids and metabolic dysfunction-associated steatotic liver disease (MASLD), focusing on the possible pathophysiological links and related treatment considerations.

RECENT FINDINGS

Glucocorticoids, commonly used for managing many inflammatory and autoimmune diseases, may contribute to the development and progression of MASLD. Glucocorticoids may induce hyperglycemia and hyperinsulinemia, thus increasing systemic and hepatic insulin resistance, a hallmark of MASLD pathogenesis. Furthermore, glucocorticoids increase adipose tissue lipolysis, and hepatic de novo lipogenesis and decrease hepatic fatty acid β-oxidation, thus promoting MASLD development. Preclinical evidence also suggests that glucocorticoids may adversely affect hepatic inflammation and fibrosis. 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) and 5α-reductase are implicated in the link between glucocorticoids and MASLD, the former enzyme increasing and the latter reducing the glucocorticoid action on the liver. Treatment considerations exist due to the pathogenic link between glucocorticoids and MASLD. Since iatrogenic hypercortisolism is common, glucocorticoids should be used at the minimum daily dose to control the subjective disease. Furthermore, the pharmacologic inhibition of 11β-HSD1 has provided favorable results in MASLD, both in preclinical studies and early MASH clinical trials. Glucocorticoids are closely linked to MASLD pathophysiology, with specific clinical and therapeutic implications.

Computed tomographic features of an axillary liposarcoma with hepatic metastasis

A geriatric dog presented for lethargy, dyspnea, and urinary incontinence. Thoracic radiographs demonstrated a large, mixed fat, and soft tissue opaque axillary mass and a pulmonary mass. Computed tomography (CT) further characterized these masses and revealed innumerable fat-attenuating hepatic masses and cranial mediastinal lymphadenopathy. Histopathology of the axillary and hepatic masses confirmed grade two primary axillary liposarcoma with hepatic metastasis. Cytology of the pulmonary mass was consistent with a pulmonary carcinoma. This is the first published CT description of fat-attenuating metastatic hepatic liposarcoma in a dog.

Triple-Phase Multidetector Computed Tomography in Distinguishing Canine Hepatic Lesions

Simple Summary

The goal of this study was to find any associations between the histologic diagnosis and the radiodensity of liver lesions. Thirty-one dogs with focal or multifocal liver lesions undergoing computed tomography examination were included in the study. Computed tomography examinations were performed before and after the application of a contrast medium, and postcontrast images were obtained in three different vascular phases; the arterial, portal, and delayed venous phases. A histological diagnosis was subsequently obtained for all of the dogs. From the results, no significant differences were identified between the benign and malignant liver lesions, nor between the individual histological types of lesions. The conclusion from this study is that triple-phase contrast-enhanced computed tomography cannot differentiate between benign and malignant liver lesions. Biopsy and further histological analysis are necessary.

Abstract

The liver has a unique vascular supply, and triple-phase contrast-enhanced computed tomography examinations are being performed in order to characterize liver lesions. This study aimed to look for any associations between the attenuation values of liver lesions and their histological classification. The inclusion criteria for this retrospective study were focal or multifocal liver lesions and histological diagnosis. All of the dogs underwent pre-contrast and triple-phase postcontrast computed tomography (CT) examinations with identical timings of the postcontrast series. Thirty-one dogs were included in the study, and various benign and malignant pathologies were identified. The results did not identify any significant differences between the benign and malignant liver lesions, nor between the individual histological diagnoses. Inflammatory lesions were significantly different compared to the normal liver parenchyma, and significant hypoattenuation was found in the portal and delayed venous phases. Hemangiosarcomas were significantly hypoattenuating to the normal liver parenchyma in the pre-contrast and arterial phases, and also to all of the benign lesions in the arterial phase. The other pathologies showed variable attenuation patterns in the different postcontrast phases, and differentiation was not possible. On the basis of this study, triple-phase contrast-enhanced computed tomography cannot differentiate between benign and malignant liver lesions, and biopsy and further histological analysis are necessary.