Discrepancy between clinical and radiological responses in non-infectious pneumonia during immunotherapy: a case report.

Background: Immunotherapy is a widely used and effective therapy for lung malignancy. However, its acting on the immune system can cause several adverse effects.

Case report: This is a case of a 74-year-old male who was admitted to the department of pulmonology due to bilateral pneumonia. The patient was treated with maintenance immunotherapy, pembrolizumab for a stage IV lung adenocarcinoma. Concomitant clinical manifestations were pleural effusion and respiratory failure, and the main comorbidities were hypertension and atrial fibrillation. The inflammatory indices, such as C-reactive protein and procalcitonin, were slightly altered, in contrast to a severely compromised clinical-radiological picture. Blood gas analysis test reported values indicative of altered gas exchange. T lymphocytopenia was found without an evident isolate of a bacterial agent. High-dose steroid treatment was initiated, and antibiotics such as cephalosporins have been administered.

Conclusions: The patient reported a good clinical response due to a poorly modified radiological picture.