A cause of fatty liver: neutral lipid storage disease with ichthyosis--electron microscopic findings

Chanarin-Dorfman Syndrome: A comprehensive review

The Chanarin-Dorfman syndrome (CDS) is a rare, autosomal recessively inherited genetic disease. This syndrome is associated with a decrease in the lipolysis activity in multiple tissue cells because of recessive mutations in the abhydrolase domain containing 5 (ABHD5) gene, which leads to the accumulation of lipid droplets in multiple types of cells. Major clinical symptoms in patients with CDS include ichthyosis and intracytoplasmic lipid droplets. The variability of clinical symptoms in patients with CDS depends on a large number of mutations involved. In this syndrome, liver involvement is an important cause of mortality and morbidity. This review aims to summarize the demographic characteristic, clinical symptoms, liver involvement and mutations in CDS patients in the literature to date.

CGI-58: Versatile Regulator of Intracellular Lipid Droplet Homeostasis

Comparative gene identification-58 (CGI-58), also known as α/β-hydrolase domain-containing 5 (ABHD5), is a member of a large family of proteins containing an α/β-hydrolase-fold. CGI-58 is well-known as the co-activator of adipose triglyceride lipase (ATGL), which is a key enzyme initiating cytosolic lipid droplet lipolysis. Mutations in either the human CGI-58 or ATGL gene cause an autosomal recessive neutral lipid storage disease, characterized by the excessive accumulation of triglyceride (TAG)-rich lipid droplets in the cytoplasm of almost all cell types. CGI-58, however, has ATGL-independent functions. Distinct phenotypes associated with CGI-58 deficiency commonly include ichthyosis (scaly dry skin), nonalcoholic steatohepatitis, and hepatic fibrosis. Through regulated interactions with multiple protein families, CGI-58 controls many metabolic and signaling pathways, such as lipid and glucose metabolism, energy balance, insulin signaling, inflammatory responses, and thermogenesis. Recent studies have shown that CGI-58 regulates the pathogenesis of common metabolic diseases in a tissue-specific manner. Future studies are needed to molecularly define ATGL-independent functions of CGI-58, including the newly identified serine protease activity of CGI-58. Elucidation of these versatile functions of CGI-58 may uncover fundamental cellular processes governing lipid and energy homeostasis, which may help develop novel approaches that counter against obesity and its associated metabolic sequelae.

Deficiency of liver Comparative Gene Identification-58 causes steatohepatitis and fibrosis in mice

Triglyceride (TG) accumulation in hepatocytes (hepatic steatosis) preludes the development of advanced nonalcoholic fatty liver diseases (NAFLDs) such as steatohepatitis, fibrosis, and cirrhosis. Mutations in human Comparative Gene Identification-58 (CGI-58) cause cytosolic TG-rich lipid droplets to accumulate in almost all cell types including hepatocytes. However, it is unclear if CGI-58 mutation causes hepatic steatosis locally or via altering lipid metabolism in other tissues. To directly address this question, we created liver-specific CGI-58 knockout (LivKO) mice. LivKO mice on standard chow diet displayed microvesicular and macrovesicular panlobular steatosis, and progressed to advanced NAFLD stages over time, including lobular inflammation and centrilobular fibrosis. Compared with CGI-58 floxed control littermates, LivKO mice showed 8-fold and 52-fold increases in hepatic TG content, which was associated with 40% and 58% decreases in hepatic TG hydrolase activity at 16 and 42 weeks, respectively. Hepatic cholesterol also increased significantly in LivKO mice. At 42 weeks, LivKO mice showed increased hepatic oxidative stress, plasma aminotransferases, and hepatic mRNAs for genes involved in fibrosis and inflammation, such as α-smooth muscle actin, collagen type 1 α1, tumor necrosis factor α, and interleukin-1β. In conclusion, CGI-58 deficiency in the liver directly causes not only hepatic steatosis but also steatohepatitis and fibrosis.

Nonalcoholic Steatohepatitis: Diagnostic Challenges

This article reviews diagnostic criteria for nonalcoholic steatohepatitis (NASH), current grading and staging methodology, and diagnostic challenges and pitfalls in routine practice. Current practice guidelines and prognostic and treatment considerations are discussed. The clinical diagnosis of nonalcoholic fatty liver disease may represent stable disease without progressive liver damage, in the form of nonalcoholic fatty liver (NAFL), or aggressive disease that will progress to advanced fibrosis, in the form of NASH. NASH is diagnosed from a liver biopsy after assessment by a pathologist to distinguish NASH from NAFL (and other histologic mimics of NASH); this distinction is critical for patient management.

Steatohepatitis and liver cirrhosis in Chanarin-Dorfman syndrome with a new ABDH5 mutation

Chanarin-Dorfman syndrome (CDS) is an autosomal recessive neutral lipid storage disease. It is very rare and characterized by ichtiosis, intracellular fat droplets in leucocytes (Jordan anomaly) and involvement of multiple tissues (skeletal muscle, central nervous system, bone marrow, eye and ear) mainly the liver. Our patients were diagnosed as CDS because they had ichtiosis, Jordon anomaly of leucocytes in peripheral blood smear, liver involvement and presence of homozygous 88 insertion C frame shift mutation on exon 4 of ABHD5/CGI-58 gene in genetic analysis. Our cases were two sisters. One of them developed severe steatohepatitis on age 19 and the other one was diagnosed as decompensated cirrhosis when she was 26 years old. We report here a new mutation in comparative gene identification-58 (CGI-58) gene causing syndactyly and steatohepatitis induced early cirrhosis.

A rare cause of Fatty liver and elevated aminotransferase levels: chanarin-dorfman syndrome: a case report

Chanarin-Dorfman syndrome is a rare, inherited metabolic disorder of neutral lipid storage characterized by ichthyosis, lipid vacuoles in leukocytes, and involvement of several internal organs, mostly the liver. Since the initial case was reported by Dorfman in 1974, nearly 50 cases have been reported, and the majority were from Middle East countries. Here, we report a 20-year-old patient with ichthyosis from Turkey, diagnosed as Chanarin-Dorfman syndrome presented with asypmtomatic elevated transaminases and hepatosteatosis, and also briefly review the updated clinical implications and management of this rarely seen syndrome. Prompt diagnosis of this syndrome avoids further unnecessary investigations in patients with ichthyosis.

Chanarin-Dorfman syndrome: clinical features of a rare lipid metabolism disorder

Chanarin-Dorfman syndrome (CDS) is a very rare neutral lipid metabolism disorder with multisystem involvement. In order to not underdiagnose the cases, screening of lipid vacuoles in neutrophils from peripheral blood smears in patients with ichthyosiform erythroderma is needed. Few case reports revealing ultrastructural findings of skin and especially liver in that disorder were observed. Here we discuss clinical and electron microscopic findings of two siblings with CDS.