Transient elastography in adult patients with cryptic dyskeratosis congenita reveals subclinical liver fibrosis: a retrospective analysis of the Aachen telomere biology disease registry.

Background: Telomere biology disorders (TBD) such as dyskeratosis congenita (DKC) lead to progressive multi-organ failure as impaired telomere maintenance disturbs cellular proliferative capacity. A wide range of hepatic manifestations from asymptomatic liver enzyme elevation to overt liver fibrosis/cirrhosis can be observed in TBD patients. However, the incidence of hepatic involvement remains unknown. Non-invasive transient elastography (TE) predicts early fibrosis by measuring liver stiffness and may uncover subclinical liver damage in TBD patients.

Methods: Liver screening procedures of nine TBD patients from the Aachen TBD Registry are being presented retrospectively. Following clinical suspicion, TBD was diagnosed using flow-FISH with telomere length (TL) below the 1% percentile and confirmed by next-generation sequencing (NGS) detecting pathogenic mutations in telomere maintenance genes TERC or TERT.

Results: In all patients, TBD was first diagnosed in adulthood. Patients showed normal to slightly elevated liver function test parameters. Hepatic ultrasound revealed inhomogeneous parenchyma in seven (77.7%) and increased liver echogenicity in four patients (44.4%). Median liver stiffness was 10.7 kilopascal (kPa) (interquartile range 8.4, 15.7 kPa). Using 7.1 kPa as cut-off, 88.8% of patients were classified as moderate fibrosis to cirrhosis.

Conclusion: Subclinical chronic liver involvement is frequent in patients with adult-onset TBD. TE could have a valuable role in the routine work-up of patients with telomere disorders including DKC for early detection of patients at risk for liver function impairment.