Syphilis is a sexually transmitted disease caused by Treponema pallidum. The prevalence of this disease has recently increased worldwide. However, pulmonary involvement in secondary syphilis is extremely rare. A 51-year-old heterosexual male patient presented with multiple pulmonary nodules with reactive serology from the Venereal Disease Research Laboratory test and positive fluorescent treponemal antibody absorption testing. A hematogenous metastatic malignancy was suspected and an excisional lung biopsy was performed. Histopathological examination showed only central necrosis with abscess and plasma cell infiltration, but no malignant cells. The patient reported sexual contact with a prostitute 8 weeks previously and a penile lesion 6 weeks earlier. Physical examination revealed an erythematous papular rash on the trunk. Secondary syphilis with pulmonary nodules was suspected, and benzathine penicillin G, 2.4 million units, was administered. Subsequently, the clinical signs of syphilis improved and the pulmonary nodules resolved. The final diagnosis was secondary syphilis with pulmonary nodular involvement.
Anti-Bacterial Agents/therapeutic use ; Biopsy ; Diagnosis, Differential ; Humans ; Lung Neoplasms/diagnosis ; Male ; Middle Aged ; Multimodal Imaging ; Multiple Pulmonary Nodules/diagnosis/drug therapy/*microbiology ; Penicillin G Benzathine/therapeutic use ; Predictive Value of Tests ; Prostitution ; Respiratory Tract Infections/diagnosis/drug therapy/*microbiology/transmission ; Sex Workers ; Syphilis/*diagnosis/drug therapy/*microbiology/transmission ; Syphilis Serodiagnosis ; Tomography, X-Ray Computed ; Treatment Outcome ; Unsafe Sex