Laryngeal Tuberculosis

Laryngeal tuberculosis (LTB) is a relatively uncommon but potentially fatal complication of tuberculosis (TB) that primarily affects the larynx and vocal cords. While the incidence of TB has declined globally in this timeline compared to the past, LTB remains a persistent public health issue in certain developing regions with limited access to healthcare and effective treatment.

Epidemiology

LTB accounts for only 1-2% of all TB cases worldwide, a lower proportion than in previous eras. However, it continues to pose a significant burden in parts of Africa, Southeast Asia, and the Indian subcontinent, where TB remains endemic and healthcare access is restricted. Socioeconomic factors like poverty, malnutrition, and HIV/AIDS co-infection contribute to the ongoing prevalence of LTB in these settings.

The disease is more common in adults, with a slight male predominance. It most often occurs as a complication of pulmonary or laryngeal TB, though primary LTB can also develop in rare cases.

Pathophysiology

The pathogenesis of LTB involves the hematogenous or lymphatic spread of Mycobacterium tuberculosis bacteria to the larynx, where they cause granulomatous inflammation and ulceration. This tends to primarily affect the vocal cords, epiglottis, and arytenoid cartilages.

In contrast to historical patterns, the disease progression in this timeline appears to be more rapid, with earlier involvement of the vocal cords and faster development of hoarseness and airway obstruction. This may be related to the emergence of more aggressive, antibiotic-resistant TB strains.

Clinical Presentation

The hallmark symptom of LTB is progressive hoarseness of voice, often the first sign of the disease. Other common symptoms include:

• Sore throat
• Odynophagia (painful swallowing)
• Stridor (high-pitched breathing sound)
• Chronic cough, sometimes with hemoptysis
• Dyspnea (shortness of breath)

Physical examination may reveal granulomatous lesions, ulceration, or edema of the laryngeal structures. In advanced cases, vocal cord paralysis and airway compromise can occur.

Diagnosis

Diagnosis of LTB requires a high index of suspicion, as symptoms can mimic other laryngeal conditions. Evaluation typically involves:

• Flexible laryngoscopy to visualize laryngeal pathology
• CT or MRI imaging to assess extent of disease
• Microbiological testing (e.g. sputum culture, biopsy) to confirm TB

Distinguishing LTB from laryngeal carcinoma can be challenging, and a tissue biopsy is often necessary.

Treatment

Treatment of LTB is complex, with a greater reliance on surgical interventions compared to historical approaches. This is due to the increasing prevalence of drug-resistant TB strains that are less responsive to antibiotic therapy alone.

First-line treatment may consist of a combination of anti-tubercular drugs, similar to pulmonary TB. However, in many cases, surgical procedures like laryngeal debridement, cordectomy, or tracheostomy are required to manage airway compromise and address localized disease. Adjunctive corticosteroids may also be used to reduce inflammation.

Despite treatment, the prognosis for advanced LTB remains quite poor, with high morbidity and mortality rates. Early detection and prompt, multidisciplinary management are critical to optimize outcomes. Addressing the underlying socioeconomic and public health factors driving LTB persistence also remains an ongoing challenge.