Acute Inflammatory Polyarthritis: A Rare Presentation of Secondary Syphilis.

Dear Editor, Syphilis can present in a myriad of ways. Recognition of this “great imitator”, which can be easily treated, will greatly reduce morbidity. A 46-year-old Chinese male presented with intense inflammatory polyarthritis of his bilateral metacarpophalangeal, wrists, elbows, knees, ankles and metatarsophalangeal joints for 2 weeks. Joint tenderness was alleviated with movement and associated with early morning stiffness lasting more than 30 minutes. He also reported rashes over his chest, scalp, hands and feet over the previous 3 months. Two days prior to the onset of the above symptoms, he experienced vomiting, abdominal pain and non-bloody diarrhoea which resolved spontaneously. He was subsequently admitted for worsening arthritis which had resulted in inability to weight-bear. He denied any history of fever, loss of appetite and loss of weight. There was no axial or gluteal pain and no urethral symptoms. Family history for autoimmune diseases was unremarkable. The patient denied any prior sexual exposure. Treatment from his physicians consisted of topical clotrimazole for his rashes and prednisolone (3 mg bd) for his arthritis, which did not significantly improve his condition. On physical examination, erythematous papulosquamous plaques were noted over his sternum, palms and soles (Figs. 1 to 3). Of note, there was faint macular hyperpigmentation over his palms. Intense synovitis was present over the aforementioned joints with tense effusion over his left knee and dactylitis of multiple toes. Conjunctival injection, cervical lymphadenopathy and right thumb onycholysis were noted. There were no genital lesions or urethral discharge. Investigations revealed elevated erythrocyte sedimentation rate (ESR) of 127 mm/h and C-reactive protein (CRP) of 133.5 mg/L. He was also noted to have hypoalbuminaemia of 25 g/L. Aside from iron deficiency anaemia, his full blood count, renal panel, liver function test and autoimmune serologies were unremarkable. No organisms were recovered from the blood cultures and fungal scrape of his