FIBROSCAN CAP IN ALPHA1 ANTITRYPSIN DEFICIENCY:
ANALYSIS IN AN UNSELECTED CONSECUTIVE POPULATION
Benini Federica1, Guerini Stefano Giovanni2, Lanzani Giovanna3, Corda Luciano4, Salmi Andrea5
- Gastroenterology Unit, ASST Spedali Civili, Brescia
- Health Protection Agency (ATS), Brescia
- Outpatient Clinic “STATIC”, Brescia
- Internal Medicine Unit 2, ASST Spedali Civili, Brescia
- Hepatogastroenterology Unit, San Camillo Hospital, Brescia
Introduction & Aims: in clinical practice the use of imaging and liver biopsy is changing [1]. Risk stratification and prognosis of liver disease is accepted for HCV, HBV etiology and proposed for non-alcoholic fatty liver disease (NAFLD) patients (pts) through non invasive fibrosis assessment as liver stiffness measurement (LSM) by transient elastography (TE), that can be performed together with controlled attenuation parameter (CAP) for the detection of fatty liver. Few data are available for patients with alpha1 antitrypsin deficiency (AATD) [2]. In a real life experience setting we aimed to: a) define prediction of clinically significative and advanced fibrosis in these pts using TE; b) compare CAP results with recently proposed cut off related to optimal stratification of steatosis in this population.
Patients & Methods: fourty-three unselected AATD patients were consecutively examined by a single operator (AS) using Fibroscan® CAP (Echosense, Paris) with M probe in a 12 months period (3 included pts’ biochemical data are missing). Fibroscan allows CAP values range from 100 to 400 db/m, and the final result is the median value of 10 valid measurements (note that CAP is calculated simultaneously with TE LSM in KPa range 0-75). All pts had 10 valid LSM measurements, and no “poorly reliable” results were found (TE-IQR/Med > 0.30 with TE/Median > 7.1 KPa), thus no patient was excluded from the analysis. TE KPa median value < 7.0 defined low risk of liver disease progression, between 7.0 and 13.9 intermediate risk, > 14 high risk of advanced fibrosis or cirrhosis. CAP value groups were defined accordingly to recently proposed cut off in dB/m [3]: S0 (<248), S1 (248), S2 (268), S3 (280).
Results: median age of enrolled pts was 50 years (range 22-80); 12 pts were female. TE KPa median value was 4.8 (range 2.0 – 26.3). TE KPa value distribution was 37 pts (86%) < 7.0; 6 pts (14%) > 7.0; 4 pts (9%) between 7.0 and 13.9; 2 pts (5%) > 14. Steatosis distribution was 57% for S0, 11% for S1, 2% for S2, 30% for S3. CAP median dB/m cut off > 280 (S3) was not associated with higher TE-median KPa value (p=0.76); it was present only in MZ (48% of total MZ) and SZ (36% of total SZ) pts, but in none pts with MS or rare mutations.
Conclusions: in an unselected, consecutive AATD pts population in real practice the prevalence of intermediate or high risk of fibrosis progression occurred in 9% and 5%, respectively. Steatosis grade according to CAP value cut off proposed [3] were S0 in 57% and > S2 in 30% pts. Fibroscan® CAP is an easy, reliable and repeatable tool and it can be used in AATD pts to identify those at higher risk to develop liver complications.
References: 1. Tapper EB et al. N Engl J Med 2017;377:756-68
2. Guillaud O et al. Clin Res Hepatol Gastroenterol 2019;77-81
3. Karlas T et al. J Hepatol 2017;66:1022-30