Tuberculous rheumatism (Poncet’s disease) is a rare, reactive, acute-onset, sterile, non-erosive, inflammatory polyarthritis associated with active extra-articular tuberculosis (TB) [7,8]. It presents as symmetrical involvement of multiple joints without evidence of active infection and resolves without residual joint damage or long-term complications [8,9]. Pulmonary TB was found to be the commonest site of TB infection (43.2%). The sites of extrapulmonary TB infection included lymphatic, renal, bone, skin, and other less common sites. Oligoarthritis was the most common rheumatological presentation (40%) followed by polyarthritis (27.6%) and monoarthritis (24.6%). The most frequently involved joints were the ankles (63%) and knees (59%). The wrists, elbows, interphalangeal joints, metacarpophalangeal joints, shoulders, and metatarsophalangeal joints were affected less frequently. Axial involvement has not yet been reported to date. Although Poncet’s disease is considered a reactive arthritis, the clinical presentation of Poncet’s disease differs from the classical pattern of reactive arthritis [10]. In contrast to reactive arthritis, the onset of symptoms in Poncet’s disease before the start of arthritis is much longer than just a few weeks, whereas resolution of arthritis upon starting of adequate anti-tuberculous therapy is mostly within a few weeks & chronic arthritis has never been reported in Poncet’s disease [11]. The pathogenesis of PD remains to be established; however, it appears to be multifactorial including the activation of CD4+ and CD8+ T cells and hypersensitivity against tuberculosis (TB) proteins [12]. Diagnosis of PD is generally difficult because it starts insidiously, progresses slowly, and has no extra-articular features. The most frequent clinical sign is the change in the range of motions with pain or painless [13].

Poncet's disease often affects young people and is slightly more common in women. Clinical findings include fever, malaise, and polyarthritis of large joints. Diagnosis of PD is generally difficult because it starts insidiously, progresses slowly, and has no extra-articular features. The most frequent clinical sign is the change in the range of motions with pain or painless. The fact that TB septic monoarthritis, in which Mycobacterium tuberculosis can be isolated from the joint, may complicate TB infection is widely known. On the other hand, active TB may also be complicated by a sterile reactive arthritis called PD, which is less recognized and therefore frequently missed.

In contrast to the usual tuberculous arthritis which is monoarticular, infectious and destructive, tuberculous rheumatism (Poncet's disease) is a non-destructive para- infective symmetric polyarthritis occurring in patients with active visceral or disseminated tuberculosis, in which there is neither evidence of bacteriological involvement of joint themselves nor any other known cause of polyarthritis detected.This finding was consistent with the clinical presentation in our case in which the patient reported to us symptoms of painful knee, upper/lower limbs, elbows and shoulder joints. The symptoms resolve completely with anti-tuberculosis therapy. In the present case as well after the initiation of anti-tubercular regimen, the patient reported marked reduction in bone pain, no morning stiffness of joints, increase in appetite, no evening rise in temperature started to reduce.

Considering the incidence of tuberculosis in our country the number of reported cases of Poncet's disease are few thereby confirming that the diagnosis needs strong clinical surmise. Poncet's initial concept of tubercular rheumatism was based on association of polyarthritis with:

1.       Active or inactive visceral tuberculosis or

2.       Family history of tuberculosis or

3.       Presence of a true tubercular joint in any patient before, coincident with or following a polyarthritis of any type

The above criterion was met with many controversies, as it was very broad based and led to diagnostic inaccuracies. The very existence of such an entity was questioned by some.

It largely remains unclear why sterile reactive polyarthritis complicates visceral TB. A vigorous immune response to mycobacteria within joints has been postulated, where mycobacterial antigen-induced activation of T cells then leads to their cross-reactivity with cartilage proteoglycans [7]. This hypersensitivity to mycobacterial antigens may be associated with HLA DR3 and/or HLA DR4 haplotypes [9]. It is interesting to note that anti-cyclic citrullinated peptide (anti-CCP) has high sensitivity and specificity for RA but now its role in active tuberculous arthritis has been reported as well [14]. Anti-CCP is no more specific to RA and frequently seen in patients with active TB [15]. TB arthritis can be confused easily with RA due to the same radiologic features including periarticular osteopenia and marginal erosions [16].

The prognosis in poncet's disease is, however, uniformly good, if the prime cause is treated promptly. In view of the high prevalence of tuberculosis in our country, it is possible that the condition is more common than is reported in the literature.