R G Kim1, P Nguyen2, R Bettencourt2,3, P S Dulai4, W Haufe5, J Hooker5, J Minocha6, M A Valasek7, H Aryafar6, D A Brenner4, C B Sirlin5, R Loomba2,3,4. 1. Division of Internal Medicine, Department of Medicine, University of California at San Diego, La Jolla, CA, USA. 2. Department of Medicine, NAFLD Translational Research Unit, University of California at San Diego, La Jolla, CA, USA. 3. Division of Epidemiology, Department of Family Medicine and Public Health, University of California at San Diego, La Jolla, CA, USA. 4. Division of Gastroenterology, Department of Medicine, University of California at San Diego, La Jolla, CA, USA. 5. Department of Radiology, Liver Imaging Group, University of California at San Diego, La Jolla, CA, USA. 6. Department of Radiology, University of California at San Diego, La Jolla, CA, USA. 7. Department of Pathology, University of California at San Diego, La Jolla, CA, USA.
Abstract
BACKGROUND: Limited data exist on the clinical presentation and non-invasive detection of liver fibrosis in adults with homozygous Z genotype alpha-1 antitrypsin (AAT) deficiency. AIMS: To compare demographic, biochemical, histological and imaging data of AAT deficient patients to normal-control and biopsy-proven non-alcoholic fatty liver disease (NAFLD) patients, and to assess the diagnostic accuracy of magnetic resonance elastography (MRE) in detecting fibrosis in AAT deficiency. METHODS: Study includes 33 participants, 11 per group, who underwent clinical research evaluation, liver biopsy (AAT and NAFLD groups), and MRE. Histological fibrosis was quantified using a modified Ishak 6-point scale and liver stiffness by MRE. Diagnostic performance of MRE in detecting fibrosis was assessed by receiver operating characteristic (ROC) analysis. RESULTS: Mean (±s.d.) of age and BMI of normal-control, AAT and NAFLD groups was 57 (±19), 57 (±18), and 57 (±13) years, and 22.7 (±2.5), 24.8 (±4.0) and 31.0 (±5.1) kg/m(2) respectively. Serum ALT [mean ± s.d.] was similar within normal-control [16.4 ± 4.0] and AAT groups [23.5 ± 10.8], but was significantly lower in AAT than NAFLD even after adjustment for stage of fibrosis (P < 0.05, P = 0.0172). For fibrosis detection, MRE-estimated stiffness had an area under the ROC curve of 0.90 (P < 0.0001); an MRE threshold of ≥3.0 kPa provided 88.9% accuracy, with 80% sensitivity and 100% specificity to detect presence of any fibrosis (stage ≥1). CONCLUSIONS: This pilot prospective study suggests magnetic resonance elastography may be accurate for identifying fibrosis in patients with alpha-1 antitrypsin deficiency. Larger validation studies are warranted.
BACKGROUND: Limited data exist on the clinical presentation and non-invasive detection of liver fibrosis in adults with homozygous Z genotype alpha-1 antitrypsin (AAT) deficiency. AIMS: To compare demographic, biochemical, histological and imaging data of AAT deficientpatients to normal-control and biopsy-proven non-alcoholic fatty liver disease (NAFLD) patients, and to assess the diagnostic accuracy of magnetic resonance elastography (MRE) in detecting fibrosis in AAT deficiency. METHODS: Study includes 33 participants, 11 per group, who underwent clinical research evaluation, liver biopsy (AAT and NAFLD groups), and MRE. Histological fibrosis was quantified using a modified Ishak 6-point scale and liver stiffness by MRE. Diagnostic performance of MRE in detecting fibrosis was assessed by receiver operating characteristic (ROC) analysis. RESULTS: Mean (±s.d.) of age and BMI of normal-control, AAT and NAFLD groups was 57 (±19), 57 (±18), and 57 (±13) years, and 22.7 (±2.5), 24.8 (±4.0) and 31.0 (±5.1) kg/m(2) respectively. Serum ALT [mean ± s.d.] was similar within normal-control [16.4 ± 4.0] and AAT groups [23.5 ± 10.8], but was significantly lower in AAT than NAFLD even after adjustment for stage of fibrosis (P < 0.05, P = 0.0172). For fibrosis detection, MRE-estimated stiffness had an area under the ROC curve of 0.90 (P < 0.0001); an MRE threshold of ≥3.0 kPa provided 88.9% accuracy, with 80% sensitivity and 100% specificity to detect presence of any fibrosis (stage ≥1). CONCLUSIONS: This pilot prospective study suggests magnetic resonance elastography may be accurate for identifying fibrosis in patients with alpha-1 antitrypsin deficiency. Larger validation studies are warranted.
Authors: Mattias Mandorfer; Theresa Bucsics; Veronika Hutya; Karin Schmid-Scherzer; Benedikt Schaefer; Heinz Zoller; Arnulf Ferlitsch; Markus Peck-Radosavljevic; Michael Trauner; Peter Ferenci; Meinhard Kneussl; Thomas Reiberger Journal: United European Gastroenterol J Date: 2018-02-28 Impact factor: 4.623