Hoarseness Beyond Cancer: Laryngeal Presentation of Tuberculosis

Abstract

Introduction:

Tuberculosis (TB) remains a leading infectious disease worldwide, with Ethiopia among the highest-burden countries. Laryngeal tuberculosis is rare, accounting for less than 1%–2% of TB cases and typically affects the posterior glottis and true vocal cords. However, atypical involvement of the subglottic region is uncommon and can closely resemble laryngeal carcinoma both clinically and radiologically, posing a significant diagnostic challenge.

Case Presentation:

We report a 64-year-old man with a 1-year history of progressive hoarseness. Neck CT demonstrated asymmetric mucosal thickening and enhancement of the glottis with anterior subglottic extension, along with a rim-enhancing necrotic prelaryngeal node which are findings highly suggestive of malignancy. Chest CT revealed right upper lobe cavitation, nodularity and tree-in-bud opacities consistent with active pulmonary tuberculosis. GeneXpert MTB/RIF confirmed Mycobacterium tuberculosis, and laryngeal biopsy revealed caseating granulomatous inflammation with acid-fast bacilli. A diagnosis of concomitant pulmonary and laryngeal tuberculosis was established, and the patient was started on standard first-line anti-tubercular therapy.

Discussion:

Laryngeal tuberculosis typically involves the posterior glottis, but in this case, anterior subglottic disease with necrotic nodal involvement created strong radiologic overlap with carcinoma. Recognition of such atypical patterns is crucial, especially in endemic regions, as misdiagnosis may lead to unnecessary surgical interventions.

Conclusion:

Persistent hoarseness with mass-like laryngeal lesions should prompt consideration of tuberculosis in endemic settings. Radiologists play a key role in identifying suggestive features and integrating them with pulmonary imaging and microbiologic results to ensure accurate diagnosis and timely treatment.

Introduction

Tuberculosis (TB) refers to a chronic granulomatous infectious disorder caused by Mycobacterium tuberculosis, primarily due to the inhalation of Mycobacterium-impregnated airborne droplets. TB is a leading infectious cause of global mortality, second only to coronavirus disease 2019 (COVID-19). It resulted in approximately 10.6 million new patients and 1.6 million deaths in 2021 globally, up from 1.5 million in 2020 to 1.4 million in 2019. These statistics suggest that the COVID-19 pandemic disrupted decades of global progress in decreasing TB mortality, and the total number of TB-related deaths in 2020 has reverted to the same level observed in 2017. ¹

TB remains a leading infectious disease worldwide, and Ethiopia is among the highest-burden countries. ² Extrapulmonary TB (EPTB) accounts for a significant minority of cases, but laryngeal TB is exceedingly rare, representing <1%-2% of TB infections. ³ Historically, laryngeal TB was more common before effective therapy, but in the modern era it is rare despite the close anatomical proximity of the larynx to the lungs. ⁴

The rarity of laryngeal TB is compounded by its notorious ability to mimic malignancy on clinical and radiologic grounds. Patients typically present with insidious hoarseness, odynophagia, or dysphagia, while imaging often shows irregular mucosal thickening, ulceration, or mass-like lesions indistinguishable from laryngeal carcinoma. ⁵ Because of this overlap, radiologists and clinicians risk misdiagnosis and potentially unnecessary invasive interventions.

Here, we report a case of laryngeal TB with unusual anterior subglottic involvement and an associated necrotic prelaryngeal lymph node in an elderly Ethiopian male with chronic hoarseness. This distribution is atypical for Laryngeal TB, which more commonly affects the posterior glottis. ⁶ The presence of rim-enhancing necrotic lymphadenopathy on top of the subglottic extension heightened suspicion for malignancy.^5,6 Concurrent pulmonary TB findings, however, helped establish the correct diagnosis. This case highlights the importance of recognizing imaging patterns that mimic carcinoma, and emphasizes the diagnostic value of considering TB in endemic settings to prevent misdiagnosis and unnecessary surgical procedures. This case has been reported in accordance with the CARE guidelines for standardized case reporting.

Case Presentation

A 64-year-old male presented to our hospital with a 1-year history of progressive hoarseness. Initially, he had attempted to manage his symptoms at home with traditional herbs, but over the past 3 months, his hoarseness worsened. He denied cough, weight loss or night sweats. There was no history of smoking, immunosuppression or any significant past medical or family history of tuberculosis or malignancy. On examination, vital signs were stable. The oropharynx appeared normal, with no visible lesions, and the gag reflex was intact. No cervical lymphadenopathy was palpable.

Baseline investigations were obtained. Complete blood count revealed hemoglobin of 11.6 g/dl, a white blood cell count of 7800/µl with mild lymphocytic predominance (56%), and a platelet count of 310 000/µl. The erythrocyte sedimentation rate (ESR) was markedly elevated at 107 mm/hour. Renal and liver function tests were within normal limits.

Pre and post contrast axial neck CT at the level of supraglottis (Figure 1A-D), glottis (Figure 1E and F) and subglottis (Figure 1G and H), show asymmetric mucosal thickening and enhancement of supraglottis (red arrows) and glottis which is more pronounced on the right. Figure 1E and F show subglottic mucosal thickening and enhancement more pronounced anteriorly (purple arrows). Figure 1G and H show a prelaryengeal rim-enhancing lesion likely representing a necrotic lymph node (green arrow and yellow arrows).

Figure 1.

(A-H) Neck CT.

Axial non-contrast chest CT at upper section shows right upper lobe diffuse airspace opacities with tree-in-bud distribution (Figure 2A-red arrow), nodule (Figure 2B-yellow arrow) and opacity with central cavity (Figure 2C-green arrow). These findings are consistent with active right upper lobe tuberculosis.

Figure 2.

(A-C) Chest CT at upper section.

Following imaging, 3 induced sputum samples were sent for nucleic acid testing and GeneXpert MTB/RIF was positive for Mycobacterium tuberculosis, sensitive to rifampin. Laryngeal biopsy confirmed the diagnosis, revealing granulomatous inflammation with central caseous necrosis, epithelioid histiocytes, Langhans-type multinucleated giant cells, and peripheral lymphoplasmacytic infiltrates. Ziehl–Neelsen staining demonstrated acid-fast bacilli, consistent with classic tuberculous histopathology.

Given the concordant chest and neck CT findings along with the positive microbiologic and histopathologic results, a diagnosis of active pulmonary and laryngeal tuberculosis was made. The patient expressed relief upon receiving a non-malignant diagnosis He has been initiated on the intensive phase of anti-tubercular therapy, consisting of isoniazid, rifampin, pyrazinamide, and ethambutol (HRZE) and is planned to be followed up at the out-patient department.

Discussion

Laryngeal tuberculosis is an uncommon manifestation of extrapulmonary TB, comprising only 1%-2% of all TB cases. ³ Although there is no isolated epidemiological data from Ethiopia, the country’s high TB burden suggests a proportional occurrence of rare forms such as Laryngeal TB. Established risk factors include older age, smoking, malnutrition, and immunosuppression. The mean age range at presentation has been consistently reported at 44.6-56.5 years. ⁷ Laryngeal TB has been historically more prevalent before effective chemotherapy but has now become rare especially in high-income countries but it persists as a “great masquerader” in endemic regions. Laryngeal tuberculosis is highly contagious, as lesions within the airway facilitate droplet transmission even during ordinary speech, making it an important public health concern despite its low incidence. ⁸

Laryngeal TB usually arises secondary to pulmonary disease, most often through bronchogenic spread when infected sputum bathes the laryngeal mucosa. ⁹ Less commonly, hematogenous occurs, and rare primary laryngeal TB has been described.^10,11 Once established, M. tuberculosis produces granulomatous inflammation with caseation, most often affecting the true vocal cords followed by false vocal cords, epiglottis, aryepiglottic fold, arytenoid cartilages, posterior commissure and/or subglottic region.^6,12 In our patient, the lesion involved the glottis with anterior subglottic extension.

On imaging, laryngeal tuberculosis often appears as mucosal thickening or mass-like lesions, ¹³ with CT and MRI typically showing diffuse or multifocal enhancement of the laryngeal mucosa. ⁵ Radiologically, Laryngeal TB progresses through 3 stages. In the acute infiltrative stage, imaging usually reveals bilateral supraglottic and glottic thickening without cartilage involvement. In the second stage which is the ulcerative stage, shallow mucosal ulcerations develop, typically superficial and rarely extending to the paraglottic spaces. Perichondritis may occasionally be seen, while calcifications are uncommon and paralaryngeal fat is usually preserved. In the chronic/sclerotic stage, lesions often evolve into localized granulomas or fibrosis, which can mimic neoplastic masses and may lead to vocal cord fixation or laryngeal stenosis.^13,14

The appearance of laryngeal TB on imaging can be difficult to differentiate from other chronic laryngeal lesions, and in elderly patients the differential is broad. Laryngeal carcinoma is the primary concern, especially in patients with smoking or alcohol history. It often presents as a unilateral mass with cartilage invasion or nodal metastases. Chronic laryngitis or inflammatory pseudotumors usually show diffuse or bilateral mucosal thickening without necrotic nodes. Fungal granulomas and rare infections (eg, actinomycosis) are uncommon and often occur in immunocompromised patients. Granulomatous diseases such as sarcoidosis or granulomatosis with polyangiitis can produce ulcerative or mass-like lesions, often with systemic manifestations. ⁵

In our patient, CT demonstrated asymmetric mucosal thickening and enhancement of the glottis extending into the anterior subglottic, along with a rim-enhancing necrotic lesion likely representing necrotic node, which mimicked laryngeal carcinoma with nodal metastasis. But certain imaging clues like bilateral and multifocal mucosal involvement, preservation of cartilage, and absence of bone erosion favored an infectious or inflammatory process. ¹³

Importantly, chest CT revealed hallmark features of post-primary pulmonary TB, including right upper lobe cavitary lesions and centrilobular nodules with a tree-in-bud pattern, reflecting possible endobronchial spread. ¹⁵ These imaging findings and a positive GeneXpert supported TB and prompted laryngeal biopsy, which confirmed the diagnosis with caseating granulomas and acid-fast bacilli.

A key limitation of this report is the short duration of follow-up, as the patient is still in the intensive phase of anti-tubercular therapy. Consequently, long-term clinical outcomes including radiologic resolution, recurrence risk, and particularly functional voice recovery cannot yet be determined. Additionally, objective post-treatment laryngeal functional assessment has not yet been performed, which limits our ability to comment on the extent of vocal cord recovery and overall functional restoration.

Key takeaway here is that the CT appearances of laryngeal TB are not specific; the possibility of TB should be raised when bilateral diffuse laryngeal lesions are seen without destruction of laryngeal architecture, especially if pulmonary TB is present.^13,16 This suspicion shall then be confirmed through histopathology from laryngeal biopsy. Early recognition of atypical imaging patterns and timely microbiologic and histopathologic confirmation, can prevent misdiagnosis, unnecessary surgery and transmission. Clinicians and radiologists should maintain a high index of suspicion to ensure prompt treatment and improved patient outcomes.

Conclusion

This case illustrates that persistent hoarseness in an elderly patient which is often presumed malignant can in fact be due to tuberculosis. Laryngeal TB is uncommon but should be considered in endemic regions and in immuno-compromised patients. Although its radiologic features overlap with carcinoma, certain clues such as diffuse mucosal thickening, caseating lymphadenopathy, and concurrent pulmonary findings like tree-in-bud nodules and cavitations may point toward the correct diagnosis. A multimodality approach, combining CT imaging with sputum PCR and biopsy, is essential. Early recognition of laryngeal TB not only enables timely treatment but also prevents transmission. For radiologists, any unusual laryngeal mass in an endemic area warrants tuberculosis in the differential diagnosis.

Key Learning Points

• Uncommon Localization: Laryngeal TB can present in the anterior subglottis, atypical from the usual posterior glottis.

• Mimics Malignancy: Imaging may resemble laryngeal carcinoma with asymmetric mucosal thickening and necrotic lymph nodes.

• Pulmonary Correlation is Crucial: Concurrent pulmonary TB helps differentiate from malignancy.

• Radiologic Clues Favor TB: Bilateral/multifocal lesions, cartilage preservation, and absence of bone erosion suggest infection.