Pulmonary Nocardiosis

Nocardiosis is a suppurative granulomatous disease caused by Nocardia; the lung is the most common organ, accounting for ~85% of pulmonary/systemic nocardiosis. Half of pulmonary cases have extrapulmonary lesions; only 1/5 of extrapulmonary cases disseminate.

Common Symptoms

Weakness; chest pain; fatigue; hemoptysis; purulent sputum; anorexia; abscess; dyspnea

Causes and Pathogenesis

(1) Etiology: Nocardia is an aerobic actinomycete; 9 species are known, 3 are pathogenic: N. asteroides, N. brasiliensis, and N. otitidiscaviarum. It is a non-motile, branching, partially acid-fast Gram-positive rod ~1 µm wide, reproducing by binary fission but remaining attached in branching filaments up to 50 µm that fragment into rods/cocci. Epidemiology: worldwide; 500-1000 cases/year in the USA, mostly adults (M:F ~2:1); no seasonal/occupational predilection. Nocardia lives in soil, aerosolizes, and is inhaled; also enters via broken skin/GI tract. It is usually sporadic; 4 small outbreaks are documented (dialysis unit, contaminated injectate, tumor/transplant units). Lymphoma, transplant, and AIDS are high-risk; alveolar proteinosis, TB, chronic granulomatous disease, alcoholism, and diabetes are associated. (2) Pathogenesis: Neutrophils inhibit Nocardia (less effectively than ordinary bacteria) via lysozyme/cationic proteins; activated macrophages and T cells are important; chronic granulomatous disease patients are highly susceptible. Pathology: suppurative granulomas with neutrophils/plasma cells/histiocytes, necrotic foci coalescing into abscesses with delicate filaments in loose granules; acute/subacute/chronic suppurative bronchopneumonia, consolidation, necrotizing cavitary pneumonia, pleural effusion/empyema, chest-wall fistula, pericardial/mediastinal extension; hematogenous spread chiefly to brain (abscess), then kidney; heart/liver/spleen/nodes rarely involved.

Treatment

Drug therapy, supportive therapy

Preventive Measures

Early detection/diagnosis is key. TCM principles: clear heat, detoxify, soften hardness, and promote drainage. Use modified Xiaochuang Yin; for fistulas take 3-6 g/day ivory powder and apply Huiyang fuming medicine.

Department to Visit

It is recommended to visit the Respiratory department; an appointment can be booked on this platform before the visit.

Warm reminder: The above information is for health science reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek medical attention at a regular hospital promptly.