Should methotrexate be categorically avoided in RA patients with COPD or RA-ILD?

Thanks for raising a very important question. It is something that every practicing Rheumatologist comes across several times during their career.

The traditional teaching has always been to avoid using Methotrexate in patients with underlying pulmonary conditions due to the associated risk of Hypersensitivity Pneumonitis, even though the incidence of this condition is very rare and can also be seen rarely with other meds including Leflunomide and TNF inhibitors.

There have been few studies done in the past couple of decades including the ones by Gaffo and Alarcon; PMID 18809822 and Bongartz et al., PMID 20155830, which failed to show an increased pulmonary mortality or exacerbation of underlying ILD from using Methotrexate. But we should alw...