Joint tuberculosis in children: causes, symptoms, diagnosis, treatment

Tuberculous lesions of the skeleton in children and adolescents are characterized by extensive destruction of bones and joints, in the absence of adequate treatment leading to an early and steadily progressing disability. In most children under 7 years of age, anamnestic data indicate the appearance of the first signs of the disease in the first 3 years of life, but the diagnosis was established at this age in only half the cases.

Pathogenesis of osteoarticular lesions, as a rule, is associated with lymphohematogenous distribution of mycobacteria to various organs during primary infection. The pathogenesis of bone complications of BCG vaccination is similar, when as a result of natural dissemination of mycobacteria of the BCG strain, either isolated tubercular foci in the bones (BCG-osteomyelitis) form from the place of their parenteral administration, or multiple specific lesions occur in different organs and systems (BCG-sepsis).

Symptoms and Diagnosis of Joint Tuberculosis in Children

Diagnosis of osteoarticular tuberculosis in children is carried out in parallel in two directions:

• determination of the activity and prevalence of tuberculosis infection;
• Determination of the prevalence of local lesions and its complications.

Assessment of the activity and prevalence of tuberculosis infection in a child with osteoarticular tuberculosis is carried out in specialized anti-tuberculosis institutions: they establish the fact of infection with the MBT, the clinical form of intrathoracic tuberculosis, the degree of sensitivity to tuberculin, and reveal other organ damage.

Diagnosis of local lesions of bones and joints is carried out on the basis of clinical and radiation methods of examination.

• Clinically assess the appearance of the affected skeleton, the presence of abscesses, fistulas, the magnitude of deformities, contractures, the degree of restriction of the functions of the organs, pathological neurological symptoms.
• The basic method of radial assessment is the standard radiography of the affected skeleton in two projections. To clarify the diagnosis using special techniques - X-ray tomography, CT, MRI. Each of these methods is used according to the indications, depending on the localization of the process and the diagnostic tasks.

In the presence of abscesses, fistulas, material of previous operations or biopsies, a bacteriological, cytological and / or histological examination is performed.

In the clinical picture of tuberculous osteitis, the leading ones are complaints about moderately expressed transient pains in the limb or joint, moderate edema, lameness (with lesions of the bones of the lower limbs), later the limitation of mobility of the affected limb, reactive arthritis. The general condition of children usually does not suffer, the symptoms of intoxication are revealed either with multiple bone foci, or with an active intrathoracic tuberculosis process. X-ray examination reveals extensive destructive cavities, usually localized in epimetaphyzes of long tubular bones, communicating with each other through the defect of the germ cell cartilage and often accompanied by periosteal reaction. Osteitis of small tubular bones is usually affected by their diaphysis, which radiologically is manifested by its swelling and massive destruction (spina ventosa tuberculosa). Radiologic changes revealed in tuberculosis osteitis often cause erroneous diagnosis of chronic osteomyelitis or a tumor and the cause for inadequate surgical interventions leading to fistula formation. The correct diagnosis is made either by a combination of clinical, radiological, laboratory data and tuberculin samples, or by histological examination of the surgical material.

Differential diagnosis of joint tuberculosis in children

Differential diagnosis for various lesions of bones and joints has its own characteristics.

Differential diagnosis of tuberculosis osteitis is carried out with focal forms of chronic hematogenous osteomyelitis, bone tumors (osteoid-osteomas, chondroblasts, giant cell tumors), mono-osseous form of fibrous dysplasia, fibrous cortical defect.

• Focal chronic hematogenous osteomyelitis is found, as a rule, in children of school age, the onset of the disease is accompanied by a temperature reaction, laboratory changes (leukocytosis, increased ESR). In young children, chronicization of osteomyelitis is extremely rare.
• The similarity of the clinical picture of some bone tumors with tuberculous osteitis is due to pain syndrome and reactive synovitis. Tumors are more common in children of school age, they differ persistent pain. Chondroblasts are characterized by epiphyseal localization of the tumor, the focus of destruction has fuzzy contours and dense inclusions. The osteoid osteoma on radiographs and computer tomograms looks like a local dilution site with a diameter of up to 1-2 cm on the background of osteosclerosis and hyperostosis. For giant cell tumors, adolescent age, metaphyseal localization of the focus, its polycyclic structure, bloating are typical.
• Dysplastic processes in the bone (mono-osseous form of fibrous dysplasia, fibro-cortical defect) are usually accompanied by minimal subjective complaints, they are often detected accidentally during an X-ray examination.
• Differential diagnosis of rheumatoid arthritis and villous synovitis with primary tuberculosis synovitis is carried out on the basis of bacteriological, biochemical and cytological investigation of synovial fluid, as well as histological examination of the biopsy synovial membrane. When hip joint is affected, differential diagnosis is also performed with Perthes' disease.

Differential diagnostics of spinal tuberculosis in children is carried out with nonspecific inflammatory lesions, congenital malformations of the vertebrae, degenerative and tumor processes. They are characterized by a low level of specific allergy according to tuberculin samples, serological and immunological diagnostics.

• For chronic hematogenous osteomyelitis of the spine, the adolescent age of patients is typical, in the anamnesis - the acute onset of the disease with severe pain syndrome and temperature reaction. In laboratory studies, moderate leukocytosis, increased ESR, and disproteinemia are detected. Radiography shows a deeper, than in tuberculosis, contact destruction of the II-III vertebral bodies with osteosclerosis of affected bodies.
• With nonspecific inflammatory processes in the spine, MRI examines the predominant change in the intervertebral disc (deformation and disappearance of the pulpous nucleus, edema or degeneration of the disc) with an increase in the signal from the bodies of the contact vertebrae.
• Among the developmental anomalies, tubular spondylitis is usually differentiated from congenital kyphoses of type I, caused by disturbances in the formation of vertebral bodies. Anomalies are characterized by the absence of anamnestic, clinical and laboratory signs of inflammation, radiation examination reveals a violation of the shape of the vertebrae while maintaining their clear contours, structure and the absence of soft tissue response.
• Among degenerative diseases of the spine in children, most often tubercular spondylitis is differentiated with juvenile osteochondrosis, usually detected in adolescence. The degenerative processes are characterized by the absence of anamnestic, clinical and laboratory signs of inflammation. On radiographs, as a rule, on the significant spine, the looseness of the end plates of the vertebral bodies, the change in their configuration, the cartilaginous nodes and the Schmorl hernia are revealed.
• Among tumorous and tumor-like diseases, most often tubercular spondylitis is differentiated with spine lesions with histiocytosis from Langerhans cells, hemangioma, osteoid osteoma, giant cell tumors. Suspicion of the tumor process always requires cytological or histological confirmation.