Alopecia Associated with Isoniazid in Isoniazid-Monoresistant Pulmonary Tuberculosis

Overview

A 22-year-old woman with pulmonary tuberculosis developed sudden alopecia 10 days after starting standard anti-tuberculosis treatment including isoniazid (INH). Discontinuation of INH led to hair regrowth within one month, and drug resistance testing confirmed INH monoresistance. This case highlights the rare but significant adverse drug reaction of INH-induced alopecia in TB treatment.

Background

Tuberculosis treatment involves multidrug regimens that often cause adverse drug reactions (ADRs), which can impact adherence and treatment success. Alopecia is a very rare ADR during anti-tuberculosis therapy and is more commonly reported in drug-resistant TB cases. Drug-induced alopecia can occur via anagen effluvium or telogen effluvium mechanisms, with anagen effluvium causing acute, reversible hair loss shortly after drug initiation. Recognizing and managing such ADRs is critical to maintaining effective TB treatment and preventing resistance development.

Data Highlights

The patient developed diffuse alopecia on day 10 of ATT including INH. Hair regrowth was observed one month after discontinuing INH. Drug resistance testing confirmed INH monoresistance, leading to regimen adjustment with moxifloxacin addition and INH discontinuation. Laboratory values included ESR 44 mm/h, CRP 25 mg/L, WBC 8.31 k/µL, with normal liver and renal function tests.

Key Findings

• Alopecia developed rapidly (within 10 days) after initiation of standard ATT including INH, consistent with anagen effluvium.
• INH was identified as the probable causative agent based on clinical timing and Naranjo ADR Probability Scale score of 3 (possible).
• Discontinuation of INH resulted in hair regrowth within one month, confirming reversibility of the ADR.
• Drug resistance testing revealed INH monoresistance, necessitating modification of the treatment regimen.
• Management included substitution of INH with moxifloxacin while continuing other first-line drugs per national guidelines.
• Alopecia as an ADR may impact patient adherence and psychological well-being, underscoring the importance of monitoring and reporting.

Clinical Implications

Clinicians should be aware that alopecia, although rare, can occur early during INH-containing TB treatment and may signal drug intolerance or resistance. Prompt recognition and discontinuation of the offending agent can lead to hair regrowth and prevent treatment interruption. Drug resistance testing is essential to guide appropriate regimen adjustments in cases of suspected INH-induced alopecia.

Conclusion

INH-induced alopecia is a rare but reversible adverse effect that may coincide with INH monoresistance in pulmonary tuberculosis. Early identification and management are crucial to ensure treatment adherence and successful outcomes.

References

1. Article Source 2024 -- Alopecia Associated with Isoniazid in Cases of Isoniazid-Monoresistant Pulmonary Tuberculosis