Isoniazid induced motor-dominant neuropathy

Area of Science:

• Neurology
• Pharmacology
• Infectious Diseases

Background:

• Tuberculosis (TB) treatment commonly uses isoniazid, a potent drug.
• Isoniazid can induce peripheral neuropathy, a serious side effect.
• Pyridoxine (vitamin B6) supplementation is known to mitigate isoniazid-induced neuropathy.

Observation:

• A 45-year-old female with psoas abscess due to Mycobacterium tuberculosis received standard four-drug anti-TB therapy, including isoniazid.
• After three months, she developed severe motor weakness and reflex loss in her lower limbs.
• Despite continued isoniazid, high-dose vitamin B6 injections were administered.

Findings:

• The patient's motor weakness significantly improved within months.
• Mild sensory deficits persisted for over two years post-treatment.
• This case highlights the potential for severe neurological effects even in seemingly low-risk patients.

Implications:

• Vigilance for isoniazid-induced neuropathy is essential, especially in individuals with slow acetylator status.
• Early recognition and high-dose vitamin B6 intervention can prevent long-term neurological morbidity.
• This reversible condition underscores the importance of monitoring drug toxicity during TB treatment.