It is a hyperreactive state of the body, an inflammatory response to subcutaneous nodule bacteria and their metabolites appearing on the pleural membrane, resulting from primary or secondary involvement of subcutaneous nodules affecting the pleura. Depending on the body's reactivity, two clinical conditions may occur: dry and exudative pleuritis.

bubble_chart Auxiliary Examination

1. Chest X-ray: In dry pleurisy, only the costophrenic angle becomes blunt on the affected side. In exudative pleurisy, a large area of uniform dense shadow can be seen with moderate or more effusion, with its upper edge presenting as an arc from the outer upper to the inner lower direction, disappearance of the costophrenic angle, and unclear diaphragmatic and cardiac shadows. With massive effusion, the mediastinum shifts to the healthy side, the intercostal spaces widen, and the diaphragm descends.
2. Ultrasound examination: Can determine the amount of pleural effusion, identify the site for thoracentesis, and differentiate between pleural effusion and pleural thickening.
3. Other tests: Blood white blood cell count and neutrophils may increase, and erythrocyte sedimentation rate (ESR) is often accelerated. Pleural fluid examination usually reveals straw-yellow exudate, with a few cases showing bloody effusion.

bubble_chart Diagnosis

1. Medical history and symptoms: The onset resembles a common cold, accompanied by fever, cough, and chest pain. When there is significant effusion, dyspnea and shortness of breath may occur. Some patients may experience night sweats, lack of strength, and loss of appetite.
2. Physical examination findings: In dry pleurisy, respiratory movement on the affected side is restricted, with localized tenderness and palpable pleural friction rub. Auscultation reveals pleural friction sounds. In exudative pleurisy with significant pleural effusion, the affected side of the chest appears full, with widened intercostal spaces, weakened respiratory movement and tactile fremitus. The trachea and heart are displaced toward the healthy side. Below the fluid level, percussion yields dullness, and breath sounds are weakened or absent. Above the fluid level, bronchovesicular breath sounds may be heard, occasionally with small crackles. In right-sided pleural effusion, hepatic dullness disappears. If pleural adhesions and thickening are present, localized chest depression may occur, with restricted respiratory movement, dullness on percussion, and weakened breath sounds.

bubble_chart Treatment Measures

1. The principle is to treat and prevent subsequent pulmonary subcutaneous nodules, alleviate symptoms to prevent pleural membrane adhesions. Anti-tuberculosis treatment can follow the initial subcutaneous nodule regimen, such as INH 0.3/d, RFP 0.45/d, EMB 0.25 three times a day, or PZA 0.5 three times a day.
2. For moderate or larger pleural effusions, perform thoracentesis 2–3 times per week, extracting 600–1000ml each time, but the drainage speed should not be too fast to prevent the occurrence of re-expansion pulmonary edema.
3. For patients with severe toxic symptoms or rapid pleural fluid accumulation, prednisone 20–30mg/d may be added. After pleural fluid decreases and symptoms improve, reduce the dosage by 2.5–5.0mg weekly.

bubble_chart Differentiation

Dry pleurisy should be differentiated from intercostal neuralgia and epidemic myalgia. Exudative pleurisy should be distinguished from wind-dampness diseases and malignant tumors causing pleural effusion.

Differential diagnosis of malignant pleural effusion and subcutaneous nodular pleural effusion