A 24-year-old man arrived at a respiratory clinic in Tianjin, China, with two weeks of cough, thick yellow sputum and low-grade fever, plus a month of back and flank pain that a prescription painkiller hadn't relieved. His blood showed a surge of eosinophils, immune cells tied to allergies and certain autoimmune diseases, and his lung scan showed patchy shadows and small nodules.
The picture pointed toward a rare autoimmune disorder that is treated with steroids and other drugs that suppress the immune system. Instead, routine blood screening and genetic testing of fluid washed from his lungs pointed to syphilis, with no rash, no sores and no swollen glands to give it away. Doctors described the case Sept. 3 in Frontiers in Medicine.
