Clinical and diagnostic studies on feline hepatic lipidosis and the significance of miRNA-122 as a biomarker

Hepatic lipidosis is one of the common causes of feline hepatic disorders in cats. Data on the incidence of feline hepatic lipidosis (FHL) in cats were gathered. FHL was diagnosed through comprehensive clinical, ultrasonographic, and haemato-biochemical examinations. Moreover, hepatocyte-derived miRNA-122 evaluation was conducted. Macroanatomical study on normal and diseased livers was performed. The present study was conducted on 40 cats (20 cases suffering from hepatic lipidosis and 20 apparently healthy control cases) from different common breeds in Egypt: Persian, Himalayan, mixed, of various ages and sexes. The cats suffering from different hepatopathies were 128 of all diseased animals; out of them 20 cats suffered from FHL. FHL was mostly recorded in Persian breeds older than 3 years, more commonly in tom cats than in queens. The most commonly recorded clinical signs were generalised weakness, weight loss, yellow skin, icteric mucous membranes, and anorexia. The liver appeared large with diffused hyperechogenicity on ultrasound. The physical examination showed significant elevation in respiratory and pulse rates. Haematological evaluation of FHL cases showed anaemia with a significant decrease in PCV, red blood cell counts, haemoglobin concentration, MCH, and MCHC; along with significant increase in total white blood cell count, platelets and absolute neutrophil count. Serum biochemistry revealed significant elevation in the levels of aspartate aminotransferase (AST), total bilirubin, and direct bilirubin in addition to a significant increase in the levels of BUN, creatinine, total cholesterol, triglyceride levels and serum glucose levels. Hepatic biomarker (miRNA-122) expression was significantly increased in cats with FHL: 5.04 ± 0.16 fold. Macroanatomically, the liver of healthy cats showed uniform mostly reddish-brown coloration and was divided into six main lobes. In FHL post mortem, livers showed yellowish discoloration appearing on parts of some hepatic lobes or affecting a whole lobe or both. Hepatomegaly was a common finding in FHL livers.