Evaluation of NAFLD and fibrosis in obese patients - a comparison of histological and clinical scoring systems

Sophia Marie-Therese Schmitz; Andreas Kroh; Tom Florian Ulmer; Julia Andruszkow; Tom Luedde; Jonathan Frederik Brozat; Ulf Peter Neumann; Patrick Hamid Alizai

doi:10.1186/s12876-020-01400-1

Evaluation of NAFLD and fibrosis in obese patients - a comparison of histological and clinical scoring systems

BMC Gastroenterol. 2020 Aug 5;20(1):254. doi: 10.1186/s12876-020-01400-1.

Authors

Sophia Marie-Therese Schmitz¹, Andreas Kroh², Tom Florian Ulmer^{2

3}, Julia Andruszkow⁴, Tom Luedde^{5

6}, Jonathan Frederik Brozat⁵, Ulf Peter Neumann^{2

3}, Patrick Hamid Alizai²

Affiliations

¹ Department of General, Visceral and Transplantation Surgery, RWTH Aachen University Hospital, Pauwelsstr.30, 52074, Aachen, Germany. sopschmitz@ukaachen.de.
² Department of General, Visceral and Transplantation Surgery, RWTH Aachen University Hospital, Pauwelsstr.30, 52074, Aachen, Germany.
³ Department of Surgery, Maastricht University Medical Center, P. Debyelaan 25, 6229, Maastricht, HX, Netherlands.
⁴ Institute of Pathology, RWTH Aachen University Hospital, Pauwelsstr, 30, 52074, Aachen, Germany.
⁵ Department of Gastroenterology, Digestive Diseases and Intensive Care Medicine, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074, Aachen, Germany.
⁶ Department of Gastroenterology, Hepatology and Infectious Diseases, University Hospital Duesseldorf, Medical Faculty of the Heinrich-Heine-University, Moorenstr. 5, 40225, Duesseldorf, Germany.

Abstract

Background: Non-alcoholic fatty liver disease (NAFLD) is a frequent condition in obese patients and regularly progresses to non-alcoholic steatohepatitis (NASH) and subsequent cirrhosis. Histologic evaluation is the gold standard for grading and staging, but invasive biopsies are associated with obvious risks. The aim of this study was to evaluate different non-invasive tools for screening of NAFLD and fibrosis in obese patients.

Methods: In a prospective cohort study liver specimens of 141 patients were taken during bariatric surgery. Serological parameters and clinical data were collected and the following scores calculated: NASH clinical scoring system (NCS), aspartate aminotransferase to platelet ratio index (APRI), FIB-4 as well as NAFLD fibrosis score (NFS). Liver function capacity was measured preoperatively by LiMAx test (enzymatic capacity of cytochrome P450 1A2). Intraoperative liver biopsies were classified using NAFLD activity score (NAS) and steatosis, activity and fibrosis (SAF) score.

Results: APRI was able to differentiate between not NASH and definite NASH with a sensitivity of 74% and specificity of 67% (AUROC 0.76). LiMAx and NCS also showed significant differences between not NASH and definite NASH. No significant differences were found for NFS and Fib-4. APRI had a high sensitivity (83%) and specificity (76%) in distinguishing fibrosis from no fibrosis (AUROC = 0.81). NCS and Fib-4 also revealed high AUROCs (0.85 and 0.67), whereas LiMAx and NFS did not show statistically significant differences between fibrosis stages. Out of the patients with borderline NASH in the histologic NAS score, 48% were classified as NASH by SAF score.

Conclusions: APRI allows screening of NAFLD as well as fibrosis in obese patients. This score is easy to calculate and affordable, while conveniently only using routine clinical parameters. Using the NAS histologic scoring system bears the risk of underdiagnosing NASH in comparison to SAF score.

Keywords: APRI; Fibrosis; Liver biopsy; NAFLD; Non-invasive tests; Scoring system; Steatosis.

MeSH terms

Biopsy
Humans
Liver / pathology
Liver Cirrhosis / diagnosis
Liver Cirrhosis / pathology
Non-alcoholic Fatty Liver Disease* / complications
Non-alcoholic Fatty Liver Disease* / pathology
Obesity / complications
Obesity / pathology
Prospective Studies