What is the anti-tubercular treatment regimen for Pott's spine with isoniazid (Isoniazid)-induced neurotoxicity?

From the Guidelines

For Pott's spine with isoniazid-induced neurotoxicity, the recommended treatment regimen is a regimen of rifampicin, ethambutol, pyrazinamide, and a fluoroquinolone, such as levofloxacin or moxifloxacin, for an initial 2 months, followed by rifampicin, ethambutol, and the fluoroquinolone for an additional 10 months. This approach is based on the most recent guidelines and evidence, including a study published in 2024 1, which suggests that the addition of a fluoroquinolone to a regimen of rifampicin, ethambutol, and pyrazinamide increases the likelihood of treatment success in patients with isoniazid-resistant TB. The key points to consider in this regimen are:

• The use of a fluoroquinolone, such as levofloxacin or moxifloxacin, which provides good bone penetration and maintains the regimen's bactericidal activity 1
• The initial 2-month phase with pyrazinamide, which may be shortened in selected situations, such as noncavitary and lower burden disease or toxicity from pyrazinamide 1
• The importance of pyridoxine (vitamin B6) supplementation to prevent further neurological complications
• Regular monitoring of liver function tests, visual acuity, and neurological status to ensure the patient's safety and adjust the treatment regimen as needed. It is essential to note that the treatment of Pott's spine requires a longer duration than pulmonary TB due to the difficulty in achieving adequate drug concentrations in bone tissue and the serious consequences of treatment failure. The most recent study published in 2024 1 provides the strongest evidence for this approach, and it is recommended to follow this guideline to ensure the best possible outcome for the patient. In cases where the patient shows signs of hepatotoxicity, further medication adjustments may be needed, potentially including streptomycin or other second-line agents based on drug susceptibility testing. Overall, the goal of the treatment regimen is to provide effective anti-tubercular coverage while minimizing the risk of further neurological complications and ensuring the patient's safety and quality of life.

From the Research

Anti-Tubercular Treatment Regimen in Pott's Spine

• The treatment of Pott's spine typically involves a four-drug antitubercular treatment regimen, which includes isoniazid, rifampicin, pyrazinamide, and ethambutol 2.
• However, isoniazid can cause neurotoxicity, and in such cases, the treatment regimen may need to be modified 3.
• The management of Pott's spine also involves rest, immobilization, and ultrasonography or computerized tomography-guided aspiration or biopsy as indicated 2.
• Surgical treatment may be necessary in some cases, especially when there is a large abscess or neurological impairment 4.

Isoniazid-Induced Neurotoxicity

• Isoniazid-induced neurotoxicity is a rare but potential side effect of anti-tubercular treatment 3.
• The symptoms of isoniazid-induced neurotoxicity can include erythematosus rash, petechiae, and cutaneous leukocytoclastic vasculitis 3.
• In cases of isoniazid-induced neurotoxicity, the treatment regimen may need to be modified to avoid further toxicity 3.
• The use of isoniazid in combination with other anti-tubercular drugs, such as rifampicin, pyrazinamide, and ethambutol, can help to minimize the risk of neurotoxicity 5.

Treatment Outcomes

• The treatment outcomes for Pott's spine are generally good, with most patients showing significant improvement within six months of treatment 2.
• However, the predictors of poor outcome include weight loss, non-ambulatory state on admission, and paradoxical worsening 2.
• The use of a four-drug antitubercular treatment regimen, including isoniazid, rifampicin, pyrazinamide, and ethambutol, can produce successful outcomes in patients with isoniazid-resistant tuberculosis 5.