Tuberculous pleurisy is an exudative inflammation caused by the direct spread of tubercle bacilli from the primary lesion near the pleura to the pleura, or through hematogenous or lymphatic pathways. It is more common in older children and is associated with systemic hypersensitivity. The primary lesion is often undetectable and is usually located on the same side as the pulmonary lesion.

bubble_chart Clinical Manifestations

1. Symptoms
   1. The onset is usually acute, with fever, cough, and early chest pain, also known as dry pleurisy. When pleural effusion increases, chest pain disappears, and dyspnea occurs, it is called exudative pleurisy.
   2. Subcutaneous nodule toxic symptoms: include weakness, emaciation, loss of appetite, night sweats, etc.
   3. There may also be concurrent allergic phenomena such as erythema nodosum, herpetic conjunctivitis, and other serositis.
2. Signs
   1. Early stage: Some children may have pleural friction rubs or no signs.
   2. Those with a small amount of effusion only have dullness on percussion at the lung base and decreased breath sounds.
   3. Those with a large amount of effusion prefer lying on the affected side, exhibiting rapid breathing, nasal flaring, weakened respiratory movement on the affected side, bulging of the chest, fullness of the intercostal spaces, tracheal shift to the healthy side, dullness on percussion, decreased or absent tactile fremitus, and tubular breath sounds may be heard in the interscapular region.
   4. OT or PPD test shows a positive or strongly positive reaction.

bubble_chart Auxiliary Examination

1. Pleural effusion
   1. Routine examination: It is an exudate with a straw-yellow appearance. The specific gravity is greater than 1.018, and the cell count is mostly below 1×10⁹/L (1000/mm3), predominantly lymphocytes, with a protein content greater than 30g/L. It is difficult to find subcutaneous node bacteria in smears or cultures.
   2. TB-PCR positive, TB-Ab positive.
2. Increased erythrocyte sedimentation rate.
3. Ultrasound examination: Helps locate the site for thoracentesis and determine the presence of encapsulated effusion.
4. X-ray examination
   1. Small effusion shows blunting or disappearance of the costophrenic angle on the affected side.
   2. Moderate effusion extends from the axilla upward and inward, with the upper margin showing a concave arc-shaped shadow.
   3. Large effusion presents as a diffuse dense shadow on the affected side, with the trachea, mediastinum, and heart displaced to the opposite side.

bubble_chart Diagnosis

Subcutaneous nodule contact history.

bubble_chart Treatment Measures

1. General treatment: Bed rest for 4 weeks, enhanced nutrition, and administration of various vitamins.
2. Anti-subcutaneous node combination therapy:
   1. INH + SM: INH: 10–20 mg/(kg·d), total course 1–1.5 years; SM: 20–30 mg/(kg·d), same as primary syndrome; maximum dose 0.6 g/d.
   2. After discontinuing SM, add: EMB: 10–15 mg/(kg·d), or the course adjusted based on condition. PAS: 200–300 mg/(kg·d).
3. Adrenal corticosteroid therapy: Early use alongside sufficient anti-subcutaneous node drugs can alleviate toxic and allergic symptoms, promote fluid absorption, and prevent pleural adhesion.
   1. Prednisone 1 mg/(kg·d), course 4–6 weeks.
   2. Hydrocortisone intrapleural injection: After the first thoracentesis for fluid drainage, inject 5–10 mg of hydrocortisone into the pleural cavity once.
4. Thoracentesis: After the first diagnostic puncture and drainage, if no compressive symptoms are present, no further puncture is needed. Currently, intrapleural injection of anti-subcutaneous node drugs is generally not recommended. However, in cases of subcutaneous node empyema, repeated puncture and injection of 10–25% PAS 1 ml, INH 25 mg, or SM 25 mg may be considered.
5. After fluid absorption, take a chest X-ray to locate the primary lesion.

bubble_chart Differentiation

1. Purulent pleurisy: Mostly a complication of bacterial pneumonia, the pleural effusion is turbid, with neutrophils or pus cells predominating in the exudate, and pyogenic bacteria are found in both smears and cultures.
2. Reactive pleurisy: Inflammation in the right upper abdomen, such as liver abscess or subphrenic abscess, often causes ipsilateral pleural reaction, with polymorphonuclear neutrophils predominating in the exudate, and chest fluoroscopy shows limited diaphragmatic movement.
3. Wind-dampness pleurisy: Relatively rare. The effusion is minimal and absorbs quickly, and the child exhibits other manifestations of wind-dampness heat.
4. Pleural effusion due to fistula disease: Mostly caused by conditions such as nephropathy, heart failure, and liver diseases, the pleural effusion appears clear or slightly turbid, with a specific gravity below 1.017, protein content less than 30g/L, and cell count less than 0.1×10⁹/L (100/mm³).
5. Malignant tumors: Relatively rare, the pleural effusion is a bloody exudate, the effusion accumulates rapidly, and tumor cells may be found in the pleural fluid. The condition deteriorates rapidly, and enlarged lymph nodes may be palpable in the neck and supraclavicular fossa. Measurements of pleural fluid lysozyme, angiotensin-converting enzyme, and adenosine deaminase (subcutaneous node >1, cancerous <1），有助於結核性與癌性胸水的鑒別。