Acute Monoarthritis of the Wrist Joint: Tuberculosis or Not?

Abstract

Background Extrapulmonary tuberculosis (EPTB) is known to have many and varied presentations. However, isolated involvement of bone with tubercular infection is uncommon. The clinical features of such infections are known to mimic chronic pyogenic osteomyelitis, Brodie abscess, or tumors, but not acute monoarthritis. Case Description We describe here an unusual case of tuberculous osteomyelitis that mimicked features of acute monoarthritis of the wrist joint. Literature Review Extraspinal tuberculous osteomyelitis is rare and comprises only about 2 to 3% of all cases of osteoarticular tuberculosis, with the hip and knee joints being the most commonly involved. An extensive literature review did not show any published report of tuberculous osteomyelitis presenting as acute monoarthritis of the wrist joint. Clinical Relevance This case underlines the importance of making EPTB an important differential diagnosis even in cases with clinical features that are completely inconsistent with tubercular infections.

Keywords: monoarthritis; tuberculosis; wrist.

Fig. 1

Plain X-ray of forearm and wrist, anteroposterior (AP) view, showing osteolytic lesion on the lateral side of the distal end of radius with ill-defined sclerosis at the medial aspect of the distal end of radius as represented by arrows.

Fig. 2

Plot of CBNAAT results for the present case. y-axis indicates fluorescence emission of the product. x-axis indicates the number of PCR cycles. The Xpert MTB/RIF assay utilizes molecular beacon technology to detect DNA sequences amplified in a nested, real-time polymerase chain reaction (PCR) assay. Five different nucleic acid hybridization probes are used in the same multiplex reaction. Together, these overlapping probes span the entire 81-bp core region of the rpoB gene. The presence of all five fluorescence signals indicates that rifampicin-susceptible M. tuberculosis (MTB) DNA has been detected. At least two but fewer than five fluorescence signals indicate the presence of rifampicin-resistant MTB. No fluorescence signal from one or fewer of the rpoB probes indicates absence of MTB-DNA (the positive signal for the internal process control indicates that the assay worked). In the test assay shown here, fluorescence signals from all five probes were detectable, indicating that rifampicin-susceptible MTB-DNA was detected.