Vedolizumab-associated diffuse interstitial lung disease in patients with ulcerative colitis: A case report

BACKGROUND Vedolizumab, a newer class of integrin antagonist biological agents, has been applied to treat patients with moderate-to-severe Crohn's disease (CD) and ulcerative colitis (UC), especially for patients who are refractory to traditional therapies and tumor necrosis factor antagonists. However, some rare but life-threatening adverse effects warrant pharmacovigilance. We describe the first fatal case of vedolizumab-associated severe diffuse interstitial lung disease in China. CASE SUMMARY We present a case of new-onset diffuse parenchymal lung disease developing under treatment with vedolizumab in a patient with UC. After two doses of vedolizumab, he developed persistent fever and progressively worsening dyspnea. Extensive workups, including bronchoalveolar lavage, transbronchial lung biopsy and metagenomic next-generation sequencing, identified no infectious causes, and other potential causes (such as tumors and cardiogenic pulmonary edema) were also excluded. As a result, a diagnosis of vedolizumab-related interstitial lung disease was established. Unfortunately, although corticosteroids and empiric antibiotics were administered, the patient eventually died of respiratory failure. CONCLUSION Vedolizumab-related interstitial lung disease in patients with UC is rare but potentially lethal. Gastroenterologists and pulmonologists should be aware of vedolizumab-related adverse drug reactions.