Tuberculous Cervical Lymphadenitis: The Silent Swelling in the Neck

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 Tuberculous Cervical Lymphadenitis: The Silent Swelling in the Neck

Author: Dr. Elias Lee
Category: Infectious Disease | Radiology | Tuberculosis
Estimated reading time: 5 minutes

Introduction

Tuberculous cervical lymphadenitis, also known as scrofula, remains the most common form of extrapulmonary tuberculosis (TB), particularly in developing countries and immunocompromised individuals. In this column, we explore a textbook case of a 22-year-old female presenting with bilateral neck masses, whose CT findings reveal the classic radiologic signs of this disease.

Clinical Case Summary

A 22-year-old previously healthy woman presented with progressive, painless swelling on both sides of the neck and difficulty swallowing. She denied systemic symptoms such as fever, sore throat, and shortness of breath.

Neck CT with contrast showed:

  • Massively enlarged necrotic lymph nodes at levels II and III bilaterally
  • Thick rim enhancement suggestive of central necrosis
  • No mass in the salivary glands or aerodigestive tract
  • Prominent lymphoid tissue in the nasopharynx and palatine tonsils

Chest X-ray was unremarkable, showing no signs of active pulmonary TB.



Final Diagnosis: Tuberculous cervical lymphadenitis

Pathophysiology & Epidemiology

Extrapulmonary TB accounts for ~20% of all TB cases in the United States, with lymphadenitis being the most common form. Cervical involvement is frequently due to hematogenous reactivation of latent TB bacilli. Risk groups include:

  • HIV/AIDS patients
  • Immunosuppressed individuals
  • Immigrants from TB-endemic regions

Imaging Pearls

Contrast-enhanced CT features include:

  • Rim-enhancing necrotic nodes
  • Potential calcifications
  • Soft tissue inflammatory changes
  • Normal thyroid and salivary glands

Chest imaging is essential to rule out concomitant pulmonary TB.

Treatment

Standard RIPE therapy includes:

  1. Rifampin
  2. Isoniazid
  3. Pyrazinamide
  4. Ethambutol
    Duration: Minimum 6 months depending on drug susceptibility.

Quiz

1. What is the most likely abnormality seen on the contrast-enhanced neck CT?

A) Hypoattenuating lesions in the bilateral tonsils
B) Posterior nasopharyngeal mass
C) Bilateral masses centered in the carotid bodies with flow voids
D) Bilateral cystic/necrotic cervical lymphadenopathy
E) Lymphoepithelial cysts in the bilateral parotid glands

Explanation: This is a classic finding in tuberculous lymphadenitis. The CT images demonstrate enlarged level II and III lymph nodes with central low attenuation and rim enhancement, indicating necrosis. These features are hallmarks of TB lymphadenitis.

2. What is the most appropriate next step in clinical management?

A) Place the patient in airborne isolation
B) Direct tissue sampling
C) Sputum sampling
D) HIV testing
E) Further imaging

Explanation: The next critical step is to confirm the diagnosis via fine-needle aspiration (FNA) or excisional biopsy. Microbiologic testing (e.g., acid-fast bacilli smear, PCR, culture) is essential for TB confirmation and drug susceptibility testing. Airborne isolation or HIV testing may be warranted but are not the immediate next steps.

3. A workup for mycobacterial infection should be obtained.

A) TRUE
B) FALSE

Explanation: Given the imaging and clinical context of bilateral necrotic lymphadenopathy, mycobacterial infection (especially TB) must be high on the differential list. Appropriate workup includes TB PCR, culture, and histopathology.

4. Which imaging study should be performed next?

A) CT head
B) CT angiogram of the neck
C) Chest x-ray
D) Full-body PET/CT

Explanation: Even in cases where cervical TB is suspected, it is critical to rule out pulmonary involvement, which determines infection control precautions and guides treatment. Chest radiography is fast, accessible, and highly informative.

5. The patient has a normal chest x-ray.

A) TRUE
B) FALSE

Explanation: The chest X-ray revealed no active disease, pleural effusion, or lung involvement. However, it is important to note that normal chest X-ray findings do not exclude TB lymphadenitis, as up to 50% of these cases occur without pulmonary disease.

6. Which of the following is NOT part of the first-line treatment for TB lymphadenitis?

A) Rifampin
B) Isoniazid
C) Pyrazinamide
D) Clarithromycin
E) Ethambutol

Explanation: The first-line RIPE regimen for TB includes Rifampin, Isoniazid, Pyrazinamide, and Ethambutol. Clarithromycin is used for nontuberculous mycobacterial infections, not Mycobacterium tuberculosis.

References

  1. Alvarez S, McCabe WR. Extrapulmonary tuberculosis revisited: a review of experience at Boston City and other hospitals. Medicine (Baltimore). 1984;63(1):25–55.
  2. Moon WK, Han MH, Chang KH, et al. CT and MR imaging of head and neck tuberculosis. Radiographics. 1997;17(2):391–402.
  3. Peto HM, et al. Epidemiology of extrapulmonary tuberculosis in the United States, 1993–2006. Clin Infect Dis. 2009;49(9):1350–1357.
  4. Rieder HL, Snider DE Jr, Cauthen GM. Extrapulmonary tuberculosis in the United States. Am Rev Respir Dis. 1990;141(2):347–351.
  5. Fontanilla JM, Barnes A, von Reyn CF. Current diagnosis and management of peripheral tuberculous lymphadenitis. Clin Infect Dis. 2011;53(6):555–562.
  6. Lee Y, et al. Ultrasonography and CT findings of tuberculous lymphadenitis. Korean J Radiol. 2001;2(4):210–215.
  7. World Health Organization. Global tuberculosis report 2023. Geneva: WHO; 2023.




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