Tuberculosis of the chest wall refers to tuberculous lesions involving the ribs, sternum, and soft tissues of the chest wall, secondary to pulmonary or pleural tuberculosis. It commonly presents as cold abscesses or chronic chest wall sinuses.
Pathology
Tuberculosis of the chest wall generally occurs through lymphatic spread, hematogenous dissemination, or direct extension from intrathoracic tuberculous lesions to lymph nodes and various layers of the chest wall, including both the skeletal system and soft tissues. Tuberculous abscesses of the chest wall frequently originate from deep lymph nodes in the chest wall and spread through the intercostal muscles to the subcutaneous tissues. This often results in the formation of a dumbbell-shaped abscess with pus cavities present internally and externally to the intercostal muscle layer, connected by a tract. In some cases, after penetrating the intercostal muscles, the abscess migrates outward and downward due to gravity, eventually extending to the lateral chest wall or upper abdominal wall.
Clinical Manifestations and Diagnosis
General systemic symptoms of chest wall tuberculosis are usually mild or absent. If the primary tuberculous lesion remains active, symptoms such as fatigue, diaphoresis, low-grade fever, and general weakness may be observed. In most patients, a localized, non-red, non-warm, painless abscess is present without other symptoms, referred to as a cold abscess. When abscesses perforate the skin, turbid, odorless pus containing caseous material may be discharged, creating persistent ulcers or sinuses with undermined edges. If a cold abscess becomes secondarily infected with pyogenic bacteria, acute inflammatory symptoms may manifest. The presence of a painless, soft mass on the chest wall that exhibits fluctuation upon palpation often indicates the possibility of chest wall tuberculosis. Aspiration of the abscess may reveal pus, and positive results from acid-fast staining and bacterial culture can confirm the diagnosis. Aspiration is typically performed from the upper part of the abscess to prevent fistula formation due to leaking pus along the needle tract. Chest X-rays may occasionally show tuberculous involvement of the lungs, pleura, or ribs, but a negative X-ray finding does not exclude chest wall tuberculosis. For chronic sinuses or ulcers, biopsies of the affected area can help establish a definitive diagnosis. Differential diagnoses include pyogenic osteomyelitis of the ribs or sternum and actinomycosis of the chest wall.
Treatment
Given that chest wall tuberculosis is a localized manifestation of systemic tuberculosis, systemic anti-tuberculous medication forms the cornerstone of treatment. Surgery is contraindicated in patients with active tuberculosis. In addition to systemic therapy, aspiration of purulent material from the tuberculous abscess followed by instillation of anti-tuberculous drugs into the cavity may be performed.
The surgical approach to treating chest wall tuberculosis involves complete excision of the diseased tissue, including affected ribs, lymph nodes, intercostal muscles, and pleura with pathological changes. All sinus tracts need to be incised, and necrotic tissue and granulation tissue should be thoroughly debrided. After repeated irrigation, healthy pedicled muscle flaps can be used to fill the residual cavity to prevent recurrence. In some cases, the tuberculous lesion may extend into the pleural cavity or pulmonary tissue, necessitating preparation for thoracotomy. Postoperatively, compression bandaging of the chest wall is required to prevent fluid accumulation in residual cavities. Drainage tubes may be placed if necessary and are typically removed 24 hours later, followed by further compression dressing.
In cases where the tuberculous abscess is complicated by pyogenic infection, incision and drainage are recommended first. Once localized infection is controlled, further management is carried out following the principles outlined above.