THU0605 AN ATYPICAL CASE OF PONCET DISEASE

Abstract

Background:Poncet disease (PD) is defined as an inflammatory rheumatism associated with visceral tuberculosis without direct bacteriological involvement of the joints [1]. It is classified as a parainfectious rather than a reactive arthritis [2].Objectives:Here by a first case of PD who presented with sterile arthritis and tuberculous spondylodiscitis.Methods:We report a case of a 40-year-old women who presented with polyarthritis in 2014. On physical examination, she had synovitis in both wrists, the metacarpophalangeal joints and the fifth proximal interphalangeal joint of the right hand. Her serum was negative for Rheumatoid Factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibody. Her C-reactive protein (CRP) was 24,5mg/l. Ultrasound revealed tenosynovitis of the superficial and deep flexor tendons on both hands with Doppler signal. The Magnetic resonance imaging (MRI) of the hands showed active synovitis in the wrists mainly in the distal radioulnar joint, erosions in the ulnar styloid as well as edematous infiltration of the soft tissue of the hands. Since she fulfilled the new ACR/EULAR 2010 criteria for RA, a diagnosis of rheumatoid arthritis (RA) was made and the patient was put on Methotrexate (MTX) 15 mg/week/po in January 2015. Eight months later, the patient developed high temperature 38°c and lumbar stiffness. A chest CT performed as part of the etiologic investigation didn’t show pulmonary manifestations but revealed a lytic vertebrae lesion. Lumbar spine MRI showed prevertebral edema and soft tissue enhancement with abnormal marrow signal in L2 and L3 which was concerning for infectious etiology. MTX was stopped. A CT-guided core needle biopsy concluded to a tuberculous spondylodiscitis. The patient was initiated on an antituberculous-therapy (ATT) for 15 months. The course was marked by the reoccurrence of low back pain. MRI of the spine was then performed and revealed persistence of spondylodiscitis and multiple abscesses at the levels of L2-L3. The ATT was resumed.Results:The patient received four drugs for 4 months, followed by isoniazid and rifampicin for 1 year. At follow up, the patient responded well to treatment with complete resolution of symptoms without sequelae. She did not present neither polyarthritis nor synovitis. Moreover, she sustained a negative CRP (2mg/dl). Ultrasound control of the wrists did not show synovitis or tenosynovitis Doppler signal. Similarly, a disappearance of effusion as well as synovitis was noted on the MRI at follow up.Conclusion:We report a unique case of Poncet disease with tubercular spondylodiscitis. It is important to recognize PD in a patient presenting with polyarthritis in order to avoid unnecessary long-term disease-modifying antirheumatic treatment. Future research is indicated to understand the etiopathogenesis of Poncet’s disease and to educate clinicians as to the importance of maintaining a high index of suspicion about this rare, yet potentially easily treatable disease.