Osteitis in the vertebral body due to Treponema pallidum.

The patient was referred to us for suspected Bechet's disease and was finally diagnosed with osteitis and skin lesions caused by secondary syphilis. The syphilitic osteitis was confirmed by PCR using a biopsy of the spinal lesion.

A previously healthy 22-year-old Japanese woman was referred to us for suspected Bechet’s disease. She gradually felt back pain over approximately one month. Two weeks later, she suffered painful oral and genital ulcers, diagnosed as a herpes virus infection. She was prescribed Vidarabine ointment by a gynecologist; however, the genital ulcer did not improve.

On examination, she had circular desquamating skin lesions with pigmentation on her palms and soles, bilaterally (Fig. 1). She also had local thoracic vertebral pain. We re-evaluated her symptoms and performed a syphilis test; her serum rapid plasma reagin (RPR) and Treponema pallidum hemagglutination assay (TPHA) levels were 1:86.4 and >1:20480, respectively. Thoracolumbar spinal magnetic resonance imaging (MRI) revealed osteitis lesions at the second and sixth thoracic vertebrae (Fig. 2). A computed tomography-guided percutaneous biopsy of the spinal lesion was performed and the presence of Treponema pallidum was confirmed by polymerase chain reaction (PCR) (Fig. 3). She was diagnosed with osteitis and skin rash caused by secondary syphilis. She was treated with 3 million units of intravenous aqueous penicillin G every 4 h for 14 days, followed by 3000 mg/day of oral amoxicillin. A follow-up (one month) vertebral MRI demonstrated substantially reduced signal, and her skin and back pain had improved.

Fig. 1

Circular desquamating rush on the palm of a 22-year-old woman with osteitis and skin rash caused by secondary syphilis.

Fig. 2

High short-T1 inversion recovery MRI signal (and low T1-weighted signal) at thoracic vertebrae indicate osteitis lesions.

Fig. 3

Treponema pallidum-specific PCR results of the spinal lesion. Lane 1 contains 100 bp ladder, lane 2 contains the positive control (100x dilution), lane 3 contains the patient’s result, and lane 4 contains the negative control (distilled water).

Though bone involvement in secondary syphilis is a rare manifestation, clinicians should have the knowledge of it because it may mimic metastatic cancer or rheumatic disease. According to the past report, the most common sites of affected bones are long bones of the limbs and the skull, and the rib, clavicle, spine and sternum are likely to be affected as well [1]. Early treatment is one of the most important considerations, because delayed diagnosis and treatment can cause irreversible destructive bony lesions.

Author contributions

According to the definition given by the International Committee of Medical Journal Editors (ICMJE), the following individuals qualify for authorship based on their substantial contributions to the manuscript’s intellectual content: Yutaka Kawahito and Naohisa Fujita, conception and design; Yumiko Fujitomo and Yoko Tanino, acquisition of data; Makoto Wada, patient management and interpretation of data. Furthermore, Shunya Kaneshita and Yutaka Kawahito participated in the writing of the manuscript. All authors have read and approved the submission of this manuscript.

Declaration of interests

The authors have no potential conflicts of interest that relate to this manuscript, and there are no funding sources to disclose.