Rationale:Lymphomatoid granulomatosis is a very rare Epstein-Barr virus-driven lymphoproliferative disease. This disease has high mortality owing to its low incidence in conjunction with nonspecific presentations, which contribute to delays in diagnosis.Patient:An 87-year-old male had a week-long history of intermittent fever and general weakness. A chest radiograph showed multifocal patchy consolidations with nodular lesions.Diagnoses:Open lung biopsy using video-assisted thoracic surgery resulted in a diagnosis of grade III lymphomatoid granulomatosis. Three days after surgery, Mycobacterium tuberculosis complex was identified from the culture of sputum samples collected at admission.Intervention and outcomes:Antituberculous treatment was commenced first. However, after 34 days of antituberculosis medication, the patient died owing to aggravated lymphomatoid granulomatosis.Lessons:This case highlights the fact that rare diseases should also be considered in differential diagnosis, particularly with a common presentation such as multiple lung nodules. Furthermore, a diagnosis of pulmonary lymphomatoid granulomatosis was made after open lung biopsy. To our knowledge, this is the first case of lymphomatoid granulomatosis coexisting with active tuberculosis in the Republic of Korea, where tuberculosis is endemic.