Actinomycosis

Actinomycosis is a chronic suppurative inflammation mainly caused by Actinomyces israelii. Modern classification places actinomycetes among anaerobic bacteria (not fungi), but because lesions resemble mycosis, they are traditionally discussed with fungal diseases. Actinomyces are ubiquitous in air, soil, and water; a few are pathogenic to humans, chiefly A. israelii. It is a normal oral saprophyte that invades via wounds from tooth extraction/trauma, or by swallowing/aspiration, mainly causing cervicofacial and thoracoabdominal disease.

Common Symptoms

Station doctor; night sweats; fatigue; fever with cough; hemoptysis...; nausea

Causes and Pathogenesis

(1) Etiology: Common pathogens are A. israelii, A. bovis, A. naeslundii, Propionibacterium propionicus, and Bifidobacterium eriksonii. Actinomycetes are prokaryotes with well-developed non-septate hyphae, no fixed nucleus (nucleoplasm only), no mitochondria/chloroplasts; cell wall is peptidoglycan-like (bacterial, not fungal); sensitive to lysozyme/penicillin but resistant to antifungals. They are anaerobic/microaerophilic normal flora, especially oral; infection follows trauma/surgery and is often polymicrobial, spreading via sinus tracts to skin, soft tissue, muscle, fascia, bone, and viscera; rare hematogenous spread. (2) Pathogenesis: Actinomyces adhere to dental plaque (salivary/glycoprotein film on enamel) via protein-protein and lectin-carbohydrate interactions, mediating coaggregation with Streptococcus milleri/sanguis—explaining polymicrobial infection and "companion" oral flora that maintain low-oxygen tension. Bacteria enter via mucosal breaks from dental infection/procedures, lower-GI perforation, or ascending genital infection. Pathology combines suppuration with intense fibrotic granulomatous inflammation; plasma cells/multinucleated giant cells are seen; foam-cell macrophages surround suppurative centers; draining sinus tracts form. Sulfur granules (1-2 mm basophilic centers with eosinophilic clubs) are typical but not universal; calcium phosphate is a host-bacterial phosphatase product.

Treatment

Traditional Chinese medicine, supportive therapy

Preventive Measures

1. Most actinomycosis is endogenous; avoid heavy immunosuppressant use. 2. Enhance general resistance and immunity.

Department to Visit

It is recommended to visit the Infectious Diseases 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.