bubble_chart Overview

Actinomycosis is a chronic specific inflammation. The head and neck region is one of the common sites for actinomycosis, which can also involve the salivary glands, though this is relatively rare.

bubble_chart Etiology

Disease Cause

The most common pathogenic bacterium found in the human body is *Actinomyces israeli*, which is anaerobic, Gram-positive, and non-acid-fast. This bacterium is present in the oral cavity of many individuals. Inflammatory conditions can lead to tissue hypoxia and reduced resistance, creating a favorable environment for the growth and spread of *Actinomyces*, which may invade the salivary glands.

Pathological Changes

After invading tissues, *Actinomyces* can cause tissue necrosis and abscess formation, containing *actinomyces granules* or so-called "sulfur granules." These granules consist of bacterial cells and filaments, appearing pale yellow and measuring up to several hundred micrometers in diameter. Microscopically, irregular basophilic lobulated structures are observed, with a homogeneous central region and radiating branching filaments at the periphery. The tips of these filaments often have a colloidal sheath membrane, forming hyaline club-like structures. Surrounding these are numerous polymorphonuclear neutrophils, followed by epithelioid cells, giant cells, eosinophils, and plasma cells. The outermost layer consists of dense fibrous connective tissue.

bubble_chart Clinical Manifestations

The age of onset is mainly between 20 and 50 years, with males being twice as likely as females.

The early symptom is the appearance of a small, painless lump in the salivary gland, which gradually enlarges. Examination reveals glandular swelling, firm tissue with indentations, and no secretion flowing out when the gland duct is compressed. The lump is immobile, and abscess formation occurs rapidly, accompanied by pain or a sensation of heat. The overlying skin appears dark red or purple, board-like in hardness, with no clear boundary from the surrounding normal tissue. As the inflammation progresses, the surface skin softens, and the abscess gradually ruptures, discharging thick, yellowish pus. "Sulfur granules" can be observed either macroscopically or through staining of the pus. After expelling pus, the inflammatory infiltrate soon forms new nodules and abscesses around the original site. These abscesses interconnect, forming fistulas and transitioning into the chronic phase, with irregular granulation tissue at the fistula openings. If accompanied by suppurative infection later, acute episodes may occur, presenting symptoms of acute cellulitis, with body temperature rising to 38.5–39°C or higher. Unlike typical inflammation, even after incision and expelling pus, the inflammation may improve, but the board-like hardness of actinomycosis does not completely subside. After healing, purplish-red atrophic scars remain.

bubble_chart Diagnosis

The diagnosis primarily relies on clinical manifestations and bacteriological examination. If an early clinical diagnosis cannot be confirmed, a biopsy may be performed when necessary.

bubble_chart Treatment Measures

Mainly antibiotics. If an abscess forms, surgical incision for expelling pus can achieve the effect of controlling inflammation.

I. Drug Therapy Antibiotics and sulfonamides Yaodui are both significantly effective for actinomycosis.

1. Generally, large doses of penicillin G are used for treatment, with more than 2 million U per day, administered intramuscularly or combined with procaine for local lesion blockade. When conditions permit, antibiotics should be selected based on drug sensitivity tests. Combining with streptomycin, tetracycline, etc., may enhance efficacy.

2. Sulfonamides can be used alone or in combination with antibiotics.

3. Iodine preparations Oral iodine preparations can achieve certain effects for actinomycosis with a prolonged course. Commonly used is a 5–10% potassium iodide solution taken orally, three times daily.

4. Immunotherapy also has certain effects. Generally, actinomycin is used for intradermal injection, with an initial dose of 0.5 ml, followed by injections every 2–3 days, gradually increasing the dose to 0.7–0.9 ml, and then incrementally adding 0.1 ml each time. The full course consists of 14 injections or until reaching 2 ml per dose. Actinomycin immunotherapy can enhance the body's immune capacity.

II. Surgical Therapy If actinomycosis has formed an abscess or left a fistula after ulceration, often accompanied by necrotic granulation tissue proliferation, surgical incision for expelling pus or scraping of granulation tissue can be performed. Due to unclear lesion boundaries within the gland and adhesions to surrounding tissues, the gland is often removed entirely.

III. Hyperbaric Oxygen Therapy Since actinomyces are anaerobic bacteria, hyperbaric oxygen therapy has been applied in recent years for actinomycosis, playing a relatively good role in inhibiting actinomyces growth. It is currently one of the comprehensive treatment methods adopted.