[A case report of prolonged pneumonia].

Takayasu's arteritis-pulmonary artery involvement (TA-PAI) is a chronic, progressive, inflammatory disease affecting the pulmonary artery and its branches. Patients typically present with non-specific respiratory symptoms, such as fever, dyspnea, and chest pain, leading to a high rate of misdiagnosis. The diagnosis of TA-PAI is currently based on the diagnostic criteria of aortitis and imaging evidence of pulmonary artery involvement. However, pulmonary artery involvement is not typically included in the diagnostic criteria for aortitis, which may lead to a significant underestimation of the diagnostic rate of TA-PAI, particularly in cases where pulmonary artery involvement is the only manifestation. This article reports the case of a 26-year-old female patient who presented with recurrent chest pain and fever. She was initially diagnosed with pneumonia in a foreign hospital but did not show significant improvement after four months of treatment. Eventually, she was diagnosed with pulmonary artery involvement in aortitis and was stabilized with hormones, immunosuppressive drugs, and pulmonary vascular intervention. By analyzing the clinical features and diagnostic and therapeutic approaches of this case, and reviewing the relevant literature, clinicians can improve their understanding of TA-PAI.