Cold abscess as a primary manifestation of thyroid tuberculosis.

Tuberculosis remains the highest cause of infection-related mortality in low- and middle-income countries. Extra-pulmonary tuberculosis is often misdiagnosed because of the nonspecific clinical presentations and gaps in the laboratory assessment. Delayed and misdiagnosis can cause increased risks of morbidity and potential community transmission. Primary thyroid tuberculosis is very rare presentation even in the endemic area. We presented a Case Illustrated of a patient with cold abscess as a primary presentation of thyroid tuberculosis. Difficulty in the diagnosis and treatment were described. Although very rare, atypical presentation of extra-pulmonary tuberculosis in the thyroid gland requires thorough anamnesis and in-depth examination. Clinicians should put high-index suspicion on high-risk patients from endemic areas with medical comorbidity including immunocompromised disease and poor nutritional status. Our report underlines the importance of thorough medical assessment for unusual presentation of thyroid tuberculosis.

Tuberculosis remains the highest cause of infection-related mortality in low- and middle-income countries [1]⁠. Extra-pulmonary tuberculosis is often misdiagnosed because of the nonspecific clinical presentations and gaps in the laboratory assessment [2]⁠. Delayed and misdiagnosis can cause increased risks of morbidity and potential community transmission [1], [2]⁠⁠⁠.

A thin 16-year-old female was referred to the clinic due to mass swelling in her neck that progressed to include skin ulcerations and dysphagia. Physical examination revealed skin ulcerations with reddish bases and a tendency to bleed and enlargement of the left thyroid lobe with irregular borders, tender, and a size of 3x3x2 cm. No signs and symptoms of hyperthyroidism were observed. Ultrasonography showed multiple hypo-echoic lesions with poorly defined borders. Needle biopsy demonstrated predominant inflammatory cells without malignant cells. Computed tomography-scan revealed amorphic hypo-dense lesions with gas bubbles and extension to the subcutaneous tissues. Debridement and left thyroid lobectomy were performed. Histopathology revealed granulomas with multi-nucleated giant cells of the Langhans type. Acid Fast Bacteria (AFB) staining and rapid culture tests were performed and confirmed the diagnosis of mycobacterium tuberculosis infection. The patient responded to antituberculous drugs showing skin wound healing after six months of treatment.

Thyroid tuberculosis is uncommon probably due to the anti-bactericidal properties of colloids within the thyroid follicles and high vascularization of the gland [3]⁠. Diagnosis of thyroid tuberculosis is often missed or delayed due to unspecific signs and symptoms and presents in various clinical manifestations including single or multifocal nodules, chronic sinuses, goiter with caseation, chronic fibrosing nodules, and cold or acute abscess [3], [4]⁠. In some circumstances, it can mimic thyroid cancer with some mechanical obstruction signs including hoarseness or dysphagia as shown in our case. Ultrasonography-guided fine-needle aspiration biopsy is appraised as an important procedure to assist the diagnosis for detailed examination of cytology and AFB culture [3], [4], [5]⁠. Although antituberculous therapy remains the mainstay treatment, surgery is still often performed to facilitate abscess drainage and to prevent total destruction of the thyroid tissue [3], [4], [5]⁠. Failure to respond to antituberculous drugs and recurrence occur in around 1% of cases due to multi-drug resistance [3]⁠. Although very rare, atypical presentation of extra-pulmonary tuberculosis in the thyroid gland requires thorough anamnesis and in-depth examination. Clinicians should put high-index suspicion on high-risk patients from endemic areas with medical comorbidity including immunocompromised disease and poor nutritional status. Our report underlines the importance of thorough medical assessment for unusual presentation of thyroid tuberculosis (Fig. 1, Fig. 2).

Fig. 1

Clinical presentation and the imaging. A patient presented with cold abscess, skin ulceration with reddish bases and tendency to bleed (A). Ultrasonography revealed multiple hypo-echoic lesions with poorly defined borders in the left thyroid lobe with extension to the surrounding tissues including skins (B). Computerized tomography scan showed multiple amorphic hypo-dense lesions, irregular borders, some pneumatic bubbles, enhanced rims in the left thyroid lobe with extension to the surrounding subcutaneous tissues and deviate trachea to the right.

Fig. 2

Some necrotic foci (*) are shown in the midst of thyroid follicles (**) lined with a layer of cuboid cells with lumen filled with colloid. Granulomas are formed in the necrotic area and are surrounded with lymphocytes, histiocytes, and multinucleated giant cells of Langhans (***, yellow arrow).

⁠Declarations

Sources of funding

None.

Ethical approval

Not applicable.

Consent

Written informed consent was obtained from the patient and her parents for reporting the medical imagery and displaying the relevant de-identified images.

Provenance and peer review

Not commissioned, externally peer reviewed.

Authors’ statement

SLA, AW conceptualized the report, produce the imaging, and finalized the manuscript. EKD and WSA provided and gave expertise in the imaging and histopathology. All authors read, provided feedback, and approved the final manuscript.

Conflict of interest

All authors disclose that there is no potential conflict of interest.