In a 5-year-old child on the fourth month of anti‑tuberculosis therapy who develops dizziness while traveling, what is the appropriate evaluation and management?

Evaluation and Management of Dizziness in a 5-Year-Old on Anti-Tuberculosis Therapy

The most likely cause of dizziness in this child on the fourth month of anti-tuberculosis treatment is ototoxicity from an injectable aminoglycoside (streptomycin, amikacin, or kanamycin), and immediate audiological assessment with strong consideration for stopping the injectable agent is required. 1

Immediate Evaluation Required

Assess for Ototoxicity

• Perform pure tone audiometry (PTA) or otoacoustic emissions (OAE) testing immediately, classified using ASHA guidelines, as dizziness may represent vestibular toxicity from aminoglycosides before hearing loss becomes apparent 1
• If any hearing loss or vestibular dysfunction is detected, strong consideration should be given to stopping or switching the injectable drug 1
• Injectable agents (amikacin, kanamycin, capreomycin) are the primary culprits for both auditory impairments and vestibular symptoms in children on anti-TB therapy 1, 2

Rule Out Other Drug-Related Causes

• Evaluate for fluoroquinolone toxicity if the child is on levofloxacin, moxifloxacin, or gatifloxacin, as neurologic effects including dizziness occur in 0.5% of patients 1
• Assess for neuropsychiatric effects from cycloserine/terizidone or isoniazid, which can cause dizziness, though these typically present with other CNS symptoms 1
• Verify correct dosing of all medications, as overdosing is associated with increased adverse events 1

Clinical Context Considerations

Motion Sickness vs. Drug Toxicity

• The fact that dizziness is "usually noted while traveling" raises the possibility of simple motion sickness, which is common in 5-year-olds
• However, new-onset motion sickness during TB treatment should not be assumed benign and requires formal audiological evaluation to exclude drug-induced vestibular toxicity 1
• The timing (4th month of treatment) is consistent with cumulative aminoglycoside toxicity, which typically manifests after weeks to months of exposure 1

Drug Regimen Assessment

• Determine if the child is on standard first-line therapy (isoniazid, rifampin, pyrazinamide, ethambutol) or drug-resistant TB regimen with injectables 1
• Injectable aminoglycosides are not part of standard drug-susceptible TB treatment in children, so their use suggests either drug-resistant TB or initial empiric therapy when resistance was suspected 1

Management Algorithm

If Ototoxicity Confirmed

1. Immediately discontinue the injectable agent 1
2. Substitute with an alternative drug based on drug susceptibility testing results 1
3. Continue other anti-TB medications if tolerated 1
4. Arrange serial audiological monitoring even after stopping the offending agent, as damage may progress 1

If Audiological Testing is Normal

1. Consider other causes: peripheral neuropathy from isoniazid or linezolid (though this typically presents with paresthesias rather than dizziness) 1
2. Evaluate for CNS involvement or paradoxical reaction requiring imaging 3
3. If truly motion sickness unrelated to medications, reassure and continue TB treatment with close monitoring 1

Critical Monitoring Going Forward

• All children on injectable aminoglycosides require baseline and monthly audiological monitoring throughout treatment 1
• The incidence of serious adverse reactions from anti-TB drugs in hospitalized children is 3.5%, with auditory impairments specifically linked to streptomycin and amikacin 2
• Hospital stays are significantly longer (median 24 vs 11 days) for children who develop serious adverse reactions 2

Common Pitfall to Avoid

Do not dismiss new neurological symptoms as unrelated to TB medications simply because they occur during travel or specific activities. Drug-induced vestibular toxicity can be triggered or exacerbated by motion, and early detection with prompt drug discontinuation is essential to prevent permanent damage 1. The fourth month of treatment represents a critical window when cumulative aminoglycoside toxicity commonly manifests 1.