Clustering of lung diseases in the family of interstitial lung disease patients

Idiopathic pulmonary fibrosis in the UK: findings from the British Thoracic Society UK Idiopathic Pulmonary Fibrosis Registry

OBJECTIVES

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease (ILD) and the most common idiopathic interstitial pneumonia. The UK IPF Registry was established in 2013 to collect data pertaining to clinical features, therapeutic approaches and outcomes. From February 2023, the Registry expanded to include any ILD with evidence of fibrosis.

DESIGN

The UK IPF Registry is a national, multicentre observational registry, including both prospective and retrospective data of patients with IPF in secondary or tertiary care. Cases eligible for inclusion were those with a diagnosis of IPF, presenting at participating centres from January 2013.

RESULTS

Between January 2013 and February 2023, 5052 IPF cases were registered from 64 participating centres. There was a male preponderance (77.8%) with mean±SD age of 74±8.1 years, 66% were ex-smokers and 76% had at least one comorbidity. Over a third (36.7%) experienced symptoms for more than 24 months prior to their first clinic visit. The majority of cases were discussed at a multidisciplinary team (MDT) meeting and the most common radiological patterns at presentation were probable (54.6%) and definite (42.7%) usual interstitial pneumonia. There was a reduction in surgical lung biopsies from 14% in 2013 to 5.5% in 2022. Antifibrotic therapy prescription rose from 36.0% in 2013 to 55.9% in 2023. The use of nintedanib (approved by National Institute of Clinical Excellence in January 2016) rose from 6.7% in 2013 to 31.5% in 2022 and pirfenidone (approved in April 2013) was initially used in around a third of cases before dropping to between 16.8% and 24.9% after nintedanib was approved.

CONCLUSION

These data reflect clinical practice across the UK and it is intended the data will have a role in informing the future of IPF care and providing a model for benchmarking, ultimately increasing knowledge and improving clinical care for this devastating disease.

Family history of pulmonary fibrosis impacts prognosis in patients with sarcoidosis

Having a family member with pulmonary fibrosis (PF) impacts the prognosis of sarcoidosis patients, as the majority of patients reporting at least one relative with PF present fibrotic characteristics and one-third develop a progressive phenotype https://bit.ly/40KC7Cr.

Familial pulmonary fibrosis: Defining inherited fibrotic lung disease in the era of clinical genetic testing

See related article

Clinical course of suspected familial and sporadic idiopathic pulmonary fibrosis: Data from the PROOF-Next registry

BACKGROUND AND OBJECTIVE

Real-life data on suspected familial fibrosis, defined as the occurrence of the disease in a patient younger than 50 and/or having at least one relative affected by pulmonary fibrosis remain scarce.

METHODS

The Belgian and Luxembourg IPF registry (PROOF-Next) is a multicentric prospective longitudinal and observational study set in Belgium and Luxembourg. We compared characteristics and clinical course of patients with suspected familial pulmonary fibrosis (FPF) and sporadic IPF.

RESULTS

We included 618 patients in the analysis, of whom 76 (12%) fulfilled criteria for FPF. They were significantly younger than sIPF (median age (range) 65 (43-87), vs. 72 (51-98), p = 0.0001). Male gender proportion and smoking status did not differ between groups, but the number of pack-year among current and former smokers was lower in FPF (20 vs. 25, p = 0.02). Besides, 87% of FPF and 76% of sIPF were treated with antifibrotic (p = 0.047). Baseline pulmonary function tests were similar in both groups, as well as median time before progression and transplant-free survival. Finally, genetic testing, performed in a minority, led to the identification of 10 telomerase-related gene variants.

CONCLUSION

Although younger and exposed to less tobacco, patients with FPF show an equally aggressive progression as observed in sporadic IPF patients. These results warrant early referral of FPF patients to expert centres for optimal management.

A new variant in the ZCCHC8 gene: diverse clinical phenotypes and expression in the lung

Introduction

Pulmonary fibrosis is a severe disease which can be familial. A genetic cause can only be found in ∼40% of families. Searching for shared novel genetic variants may aid the discovery of new genetic causes of disease.

Methods

Whole-exome sequencing was performed in 152 unrelated patients with a suspected genetic cause of pulmonary fibrosis from the St Antonius interstitial lung disease biobank. Variants of interest were selected by filtering for novel, potentially deleterious variants that were present in at least three unrelated pulmonary fibrosis patients.

Results

The novel c.586G>A p.(E196K) variant in the ZCCHC8 gene was observed in three unrelated patients: two familial patients and one sporadic patient, who was later genealogically linked to one of the families. The variant was identified in nine additional relatives with pulmonary fibrosis and other telomere-related phenotypes, such as pulmonary arterial venous malformations, emphysema, myelodysplastic syndrome, acute myeloid leukaemia and dyskeratosis congenita. One family showed incomplete segregation, with absence of the variant in one pulmonary fibrosis patient who carried a PARN variant. The majority of ZCCHC8 variant carriers showed short telomeres in blood. ZCCHC8 protein was located in different lung cell types, including alveolar type 2 (AT2) pneumocytes, the culprit cells in pulmonary fibrosis. AT2 cells showed telomere shortening and increased DNA damage, which was comparable to patients with sporadic pulmonary fibrosis and those with pulmonary fibrosis carrying a telomere-related gene variant, respectively.

Discussion

The ZCCHC8 c.586G>A variant confirms the involvement of ZCCHC8 in pulmonary fibrosis and short-telomere syndromes and underlines the importance of including the ZCCHC8 gene in diagnostic gene panels for these diseases.

KIF15 missense variant is associated with the early onset of idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) has an unknown aetiology and limited treatment options. A recent meta-analysis identified three novel causal variants in the TERT, SPDL1, and KIF15 genes. This observational study aimed to investigate whether the aforementioned variants cause clinical phenotypes in a well-characterised IPF cohort.

METHODS

The study consisted of 138 patients with IPF who were diagnosed and treated at the Helsinki University Hospital and genotyped in the FinnGen FinnIPF study. Data on > 25 clinical parameters were collected by two pulmonologists who were blinded to the genetic data for patients with TERT loss of function and missense variants, SPDL1 and KIF15 missense variants, and a MUC5B variant commonly present in patients with IPF, or no variants were separately analysed.

RESULTS

The KIF15 missense variant is associated with the early onset of the disease, leading to progression to early-age transplantation or death. In patients with the KIF15 variant, the median age at diagnosis was 54.0 years (36.5-69.5 years) compared with 72.0 years (65.8-75.3 years) in the other patients (P = 0.023). The proportion of KIF15 variant carriers was 9- or 3.6-fold higher in patients aged < 55 or 65 years, respectively. The variants for TERT and MUC5B had similar effects on the patient's clinical course, as previously described. No distinct phenotypes were observed in patients with the SPDL1 variant.

CONCLUSIONS

Our study indicated the potential of KIF15 to be used in the genetic diagnostics of IPF. Further studies are needed to elucidate the biological mechanisms of KIF15 in IPF.