Healthcare Provider Information about Non-Alcoholic Steatohepatitis (NASH)
NASH is a chronic liver disease characterized by liver cell injury (hepatocellular ballooning) and inflammation as a result of fatty accumulation (steatosis) seen in at least 5% of hepatocytes.
This leads to liver scarring and the development of fibrosis (scored F0 to F4). As fibrosis worsens, liver-related morbidity (including cirrhosis and hepatocellular carcinoma) and mortality increase.
Labcorp can help meet your NAFLD-NASH needs
Contact a Labcorp representative to learn more about how we can help meet your NASH and NAFLD testing needs.
NASH guidance from Health Organizations
A number of health organizations have issued guidance, guidelines and/or recommendations regarding the diagnosis of and treatments for NASH. The following documents are provided for informational purposes.
- United States National Institute of Health
- American Diabetes Association Standards of Medical Care 2023
- AACE Guidelines on NAFLD
- AGA Section
- European Association for the Study of the Liver (EASL), European Association for the Study of Diabetes (EASD) and European Association for the Study of Obesity (EASO)
- American Association for the Study of Liver Diseases (AASLD)
- Expert Committee on NAFLD (ECON) and the North American Society of Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN)
Symptoms and Diagnosis of NASH
- The symptoms of NASH may be very non-specific and can include fatigue, daytime tiredness, or abdominal pain early in the disease.
- NAFLD patients with obesity and features of the metabolic syndrome have a higher risk of progression to NASH. Not all patients have all manifestations of the metabolic syndrome, however.
- With the development of NASH, the cardio-metabolic profile worsens, leading to a higher risk of cardiovascular events and death.
- It is usually discovered incidentally due to elevated liver enzymes, abnormal imaging studies or surgery.
- As cirrhosis advances, NASH-specific symptoms are more commonly manifested.
NASH, NAFLD, & NIS4: Ask an Expert
Dr. Connelly, the lead scientist behind Labcorp's NASH and NAFLD portfolio, discusses the clinical significance of NASH and what positive NASH and liver fibrosis test results mean for patients.
Fibrosis scoring and what does it mean?
Histology is important in the evaluation of NAFLD. There have been three scoring systems for NAFLD in recent years, with the most recent being a semiquantitative scoring system validated by the National Institutes of Health–sponsored Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) in 2001. This system outlines the NAFLD activity score (NAS), a composite score of steatosis, lobular inflammation, cytological ballooning, and fibrosis (disease stage).
NASH CRN Scoring System: NAS and Fibrosis Score
Fibrosis Score 1a
|
|
| Steatosis Grade | |
| Degree | 0 |
| Description (%) | <5 |
Fibrosis Score 1b
|
|
| Steatosis Grade | |
| Degree | 1 |
| Description (%) | 5-33 |
Fibrosis Score 1c
|
|
| Steatosis Grade | |
| Degree | 2 |
| Description (%) | 34-66 |
Fibrosis Score 2
|
|
| Steatosis Grade | |
| Degree | 3 |
| Description (%) | >66 |
Fibrosis Score 3
|
|
Fibrosis Score 4
|
|
Fibrosis scoring and what does it mean?
Histology is important in the evaluation of NAFLD. There have been three scoring systems for NAFLD in recent years, with the most recent being a semiquantitative scoring system validated by the National Institutes of Health–sponsored Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) in 2001. This system outlines the NAFLD activity score (NAS), a composite score of steatosis, lobular inflammation, cytological ballooning, and fibrosis (disease stage).
NASH CRN Scoring System: NAS and Fibrosis Score
| Steatosis Grade | Fibrosis Score | ||
| Degree | Description (%) | 0 | None |
| 0 | <5 | 1a | Mild (delicate) zone 3 perisinusoidal fibrosis |
| 1 | 5-33 | 1b | Moderate (dense) zone 3 perisinusoidal fibrosis |
| 2 | 34-66 | 1c | Portal/periportal fibrosis only |
| 3 | >66 | 2 | Zone 3 perisinusoidal fibrosis with portal/periportal fibrosis |
| 3 | Bridging Fibrosis | ||
| 4 | Cirrhosis | ||
*NASH Clinical Research Network (CRN) Scoring System
NAFLD/NASH Research from Labcorp
Looking for research on NAFLD and NASH? Review the scientific papers and presentations about NAFLD and NASH that Labcorp has played a role in developing:
More NASH Research from Labcorp Drug Development
Labcorp Drug Development is the industry thought leader in NASH drug development. Its NASH Education Center provides additional NASH resources, including webinars, case studies and scientific articles related to NASH.