Osteoraticular Tuberculosis-Brief Review of Clinical Morphological and Therapeutic Profiles

Abstract

Osteoarticular tuberculosis (OATB) is a rare form of tuberculosis (TB) whose incidence rose significantly nowadays especially in the underdeveloped countries. The main risk factors predisposing to this new challenge for the medical system are the Human Immunodeficiency Virus (HIV) epidemic, the migration from TB endemic areas and the development of drug and multidrug-resistant strains of Mycobacterium tuberculosis (Mt). The disease affects both genders and any age group although the distribution depending on gender is controversial and that depending on age has a bimodal pattern. In most cases the initial focus is elsewhere in the organism and the most frequent pathway of dissemination is lympho-haematogenous. The clinical picture includes local symptoms as pain, tenderness and limitation of motion, with some particularities depending on the segment of the osteoarticular system involved, sometimes accompanying systemic symptoms specific for TB and other specific clinical signs as cold abscesses and sinuses. The radiographic features are not specific, CT demonstrates abnormalities earlier than plain radiography and MRI is superior to plain radiographs in showing the extent of extraskeletal involvement. Both CT and MRI can be used in patient follow-up to evaluate responses to therapy. TBhas been reported in all bones of the body, the various sites including the spine (most often involved) and extraspinal sites (arthritis, osteomyelitis and tenosynovitis and bursitis). Two basic types of disease patterns could be present: the granular type (most often in adults) and the caseous exudative type (most often in children) one of which being predominant. The algorithm of diagnosis includes several steps of which detection of Mt is the gold standard. The actual treatment is primarily medical, consisting of antituberculosis chemotherapy (ATT), surgical interventions being warranted only for selected cases. It is essential that clinicians know and refresh their knowledge about manifestations of OATB.

Keywords: bones; extrapulmonary tuberculosis; joints; osteoarticular system.

Figure 1

Imaging investigations. (a) Arm radiography: Solitary multilocular lytic lesion with a sclerotic rim (yellow oval); (b) Profile Spine CT-STIR1: L2-L3 “mirror” caries with intervertebral disk evanescence (red circle); (c) MRI of the lumbar spine T1-w sagittal plane: Erosive changes involving the inferior aspect of L1 and superior part of L2 with collapse of the intervertebral space (red arrows) and paravertebral abscess involving the spinal canal (yellow arrow) and the prevertebral soft tissues (green arrow)

Figure 2

Spine Involvment

Figure 3

Extraspinal sites

Figure 4

Main histological patterns of OATB. UP: Granular type-Giant Langhans cell granulomas (blue arrows) placed (a) in the synovium (b) in the cancellous bone, H-E stain, x10; DOWN Caseous necrosis (red arrows) (a) in the synovium x4 (b) in the compact bone, x10, H-E stain