Unilateral thyroid swelling due to actinomycosis.

Area of Science:

• Endocrinology
• Infectious Diseases
• Pathology

Background:

• Actinomycosis is a rare bacterial infection typically affecting the cervicofacial region, but can manifest in other sites.
• Thyroid actinomycosis is an exceptionally uncommon presentation of this infection, often presenting as a mass or swelling.
• Accurate diagnosis is crucial for appropriate management and to differentiate from other thyroid pathologies like malignancy.

Observation:

• A 27-year-old farm worker presented with unilateral thyroid swelling.
• The swelling was initially suspected to be a neoplastic or inflammatory process.
• Clinical examination revealed a localized, firm enlargement of one thyroid lobe.

Findings:

• Ultrasound-guided fine needle aspiration biopsy was performed for cytopathological analysis.
• Microscopic examination of the biopsy sample revealed characteristic sulfur granules and filamentous bacteria consistent with Actinomyces species.
• Histopathological correlation confirmed the diagnosis of thyroid actinomycosis.

Implications:

• This case underscores the importance of considering actinomycosis in the differential diagnosis of unilateral thyroid swelling, especially in individuals with relevant occupational or environmental exposures.
• Ultrasound-guided fine needle biopsy is an effective and minimally invasive method for diagnosing thyroid actinomycosis.
• Prompt diagnosis and treatment of thyroid actinomycosis can prevent complications and unnecessary surgical interventions.