nonalcoholic fatty liver disease
Introduction
Introduction to nonalcoholic fatty liver disease Non-alcoholic fatty liver disease (NAFLD) refers to a land-based pathological syndrome, including simple fatty liver, caused by alcohol and other well-defined liver-damaging factors, with diffuse hepatic macrobubble fat becoming a major feature. And the evolution of steatohepatitis (NASH) and cirrhosis. NAFLD is divided into two major categories: primary and secondary. The former is related to insulin resistance and genetic susceptibility, while the latter is caused by some special reasons. Overweight is caused by excessive weight gain and overweight, obesity, diabetes. Hyperlipidemia and other metabolic syndrome-associated fatty liver, as well as cryptogenic fatty liver, belong to the primary NAFLD category; and malnutrition, total parenteral nutrition, weight loss after bariatric surgery, drug/environmental and industrial poisons Fatty liver caused by poisoning, etc. belongs to the category of secondary NAFLD. basic knowledge The proportion of sickness: 0.003 Susceptible people: no special people Mode of infection: non-infectious Complications: hyperlipidemia, liver fibrosis, cirrhosis
Cause
The cause of nonalcoholic fatty liver disease
NAFLD is divided into two major categories: primary and secondary. The former is related to insulin resistance and genetic susceptibility, while the latter is caused by some special reasons. Overweight is caused by excessive weight gain and overweight, obesity, diabetes. Metabolic syndrome-related fatty liver such as hyperlipidemia, and cryptogenic fatty liver belong to the primary NAFLD category; and malnutrition, total parenteral nutrition, weight loss after bariatric surgery, drug, environmental and industrial poisons Fatty liver caused by poisoning, etc. belongs to the category of secondary NAFLD.
Prevention
Nonalcoholic fatty liver disease prevention
Losing weight, lowering blood sugar, scientific diet, and moderate exercise are the key to prevention.
Complication
Nonalcoholic fatty liver disease complications Complications hyperlipidemia liver fibrosis cirrhosis
1. Hyperlipidemia.
2. Hyperviscosity.
3. Liver fibrosis and cirrhosis.
4. Metabolic syndrome.
5. Atherosclerosis.
Symptom
Nonalcoholic fatty liver disease symptoms Common symptoms Liver fibrosis, weak fat infiltration, dyspepsia, hepatolenticular degeneration
1, no drinking history or drinking alcohol equivalent to ethanol, men <140g per week, women <70g per week.
2, in addition to the clinical manifestations of the primary disease, there may be non-specific symptoms and signs such as fatigue, indigestion, liver pain, liver splenomegaly.
3. There may be components related to metabolic syndrome such as overweight and/or visceral obesity, increased fasting blood glucose, dyslipidemia, and hypertension.
Examine
Non-alcoholic fatty liver disease check
1. Imaging examination
Ultrasound, CT and MRI are effective tools for diagnosing fatty liver. Among them, B-ultrasound is high, CT is specific, and MRI is valuable for the diagnosis of focal fatty liver and intrahepatic space-occupying lesions. And CT and MRI can also semi-quantitatively analyze intrahepatic fat content, but the existing imaging examination can not reflect the presence of inflammation and fibrosis in fatty liver, and can not accurately determine the serious condition of liver function damage and its cause, therefore Imaging studies cannot perform clinical pathological typing of NAFLD.
2. Histopathological examination
Can be used for clinical pathological typing of NAFLD.
3. Serological examination
Diagnosis
Diagnosis and identification of nonalcoholic fatty liver disease
diagnosis
First, clinical diagnostic criteria
Any of the following items 1 through 5 and 6 or 7 can be diagnosed as NAFLD.
1. No alcohol history or alcohol consumption is equivalent to ethanol in men <140g per week, women <70g per week.
2. Excluding viral hepatitis, drug-induced liver disease, total parenteral nutrition, hepatolenticular degeneration, etc. can lead to specific diseases of fatty liver.
3. In addition to the clinical manifestations of the primary disease, there may be non-specific symptoms and signs such as fatigue, indigestion, pain in the liver area, hepatosplenomegaly.
4. There may be weight loss and/or visceral obesity, increased fasting blood glucose, dyslipidemia, hypertension and other components related to metabolic syndrome.
5. Serum transaminase and Y-glutamine transpeptase levels may have a mild to moderate increase (less than 5 times the upper limit of normal), usually with alanine aminotransferase (ALT) increased.
6. Liver imaging findings are consistent with imaging diagnostic criteria for diffuse fatty liver.
7. Liver biopsy Histopathological changes meet the pathological diagnostic criteria for fatty liver disease.
Second, imaging diagnosis
Imaging examination used Ding to reflect the distribution of liver fat infiltration, roughly judge the degree of diffuse fatty liver, suggesting the presence of dominant cirrhosis, but it can not distinguish between simple fatty liver and NASH, and it is difficult to detect <33% of liver Fine sativa change, should pay attention to diffuse liver echo enhancement and density reduction can also be seen in chronic liver disease such as cirrhosis.
(1) B-ultrasound diagnosis
1. The near field echo of the liver area is diffusely enhanced (stronger than the kidney and spleen), and the far field echo is gradually attenuated.
2. The structure of the intrahepatic duct is unclear.
3. The liver is mild to moderately swollen and the edges are rounded.
4. Color Doppler flow imaging can reduce the color flow signal in the liver or reduce it, but the blood vessels in the liver go normal.
5. The right hepatic envelope and transverse echo are unclear or incomplete.
(two) CT diagnosis
Diffuse liver density decreased, the ratio of liver to spleen CT value was less than or equal to 1, diffuse liver density decreased, liver / spleen CT ratio 1.0 but greater than 0.7 was mild; liver / spleen CT ratio 0.7 but dry 0.5 is moderate; liver/spleen CT ratio 0.5 is severe.
Third, histopathological diagnosis
According to whether the diseased liver tissue is accompanied by inflammatory reaction and fibrosis, NAFLD can be divided into: simple fatty liver, NASH, HASH-related cirrhosis.
(1) Simple fatty liver
According to the range of liver cell steatosis occupied by liver cell steatosis, it is divided into 4 degrees (F0 ~ 4): FO < 5% hepatocyte steatosis; F1 5% ~ 30% hepatocyte steatosis; F2 31% ~ 50 % hepatocyte steatosis; F3 51% to 75% hepatocyte steatosis; F4 more than 75% hepatocyte steatosis.
(2) NASH
The degree of fatty liver in NASH is consistent with that of simple fatty liver, which is divided into 4 degrees (F0~4). According to the degree of inflammation, NASH is divided into 3 grades (G0~3): G0 has no inflammation; G1 acinar 3 band presents a few balloon-like Hepatocytes, follicular necrosis scattered in individual follicles; G2 acinar 3 with balloon-like hepatocytes, focal necrosis in the acinus increased, mild to moderate inflammation in the portal area; G3 acinus 3 with a wide balloon-like Liver cells, focal follicular necrosis in the acinus, mild to moderate inflammation in the portal area with or around the portal area inflammation.
According to the extent and morphology of fibrosis, NASH liver fibrosis is divided into 4 stages (S0~4): S0 is not fibrosis; S1 acinar 3 is focal or extensive sinus per pericellular fibrosis; S2 fibrosis Expanded into the portal area, focal or extensive portal area of astral fibrosis; S3 fibrosis extends around the portal area, focal or extensive bridging fibrosis; S4 cirrhosis.
NASH histopathological diagnosis report: NASA-F (0 ~ 4) G (0 ~ 3) S (0 ~ 4) F: fatty liver index; G: inflammation grade; S: fibrosis stage.
The histological features of NASH in children have mild inflammation in the lobular area. The inflammation in the portal area is heavier than that in the lobular area. There is little balloon-like change. The fibrosis in the lobes is not obvious. The fibrosis in the portal area and its surrounding area is obvious. It may be cryptogenic liver. An important cause of hardening.
Hepatocyte ribosylation is a histological feature of "static NASH."
Differential diagnosis
Identification of fatty liver caused by alcoholic fatty liver and other well-defined liver damage factors.
