From the Guidelines
Pulmonary tuberculosis (TB) in the Philippines is categorized into four main classifications: Category I, Category II, Category III, and Category IV, which guide treatment approaches based on the severity and drug resistance of the disease. The categorization of pulmonary TB in the Philippines is crucial for determining the appropriate treatment protocols and prioritizing resources for TB control.
- Category I includes new smear-positive pulmonary TB cases, new smear-negative pulmonary TB with extensive parenchymal involvement, and severe forms of extrapulmonary TB.
- Category II encompasses previously treated TB cases including treatment failures, relapses, and return after default.
- Category III covers new smear-negative pulmonary TB cases with minimal parenchymal involvement and less severe forms of extrapulmonary TB.
- Category IV includes drug-resistant TB cases, particularly multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB), which requires specialized drug regimens based on drug susceptibility testing, as recommended by the World Health Organization 1. The treatment regimens for these categories are based on the latest guidelines, with Category I and III patients typically receiving a 6-month regimen of isoniazid, rifampicin, pyrazinamide, and ethambutol for 2 months, followed by isoniazid and rifampicin for 4 months, as outlined in the European Association of Urology guidelines 1. However, for MDR-TB cases, the treatment regimen should include at least 5 effective TB medicines during the intensive phase, including pyrazinamide and 4 core second-line TB medicines, as recommended by the World Health Organization 1. It is essential to note that the treatment regimens may vary depending on the patient's condition and drug susceptibility testing results. Overall, the categorization of pulmonary TB in the Philippines plays a vital role in ensuring that patients receive the most effective treatment and that resources are allocated efficiently for TB control.
From the Research
Categories of Pulmonary Tuberculosis (TB) in the Philippines
The categories of pulmonary TB in the Philippines are based on the treatment regimens used. According to the study 2, the National Tuberculosis Programme in the Philippines uses two main categories:
- Category I: This regimen is used for new patients with pulmonary TB, including those with mono- or polyresistant TB.
- Category II: This regimen is used for patients who have previously been treated for TB, including those with mono- or polyresistant TB.
Treatment Outcomes
The study 2 found that the Category I regimen achieved a treatment success rate of more than 85% among new patients with the same drug resistance patterns, while the Category II regimen produced poor outcomes. The poor outcomes of the Category II regimen could be attributed to other factors such as patient behavior and comorbidities, rather than drug resistance.
Other Treatment Regimens
Other studies have investigated the use of different treatment regimens for pulmonary TB, including:
- A fixed-dose combination (FDC) formulation of ethambutol, isoniazid, rifampicin, and pyrazinamide 3
- Rifampicin plus levofloxacin or isoniazid 4
- A 6-month therapy with isoniazid and rifampicin compared with isoniazid, rifampicin, and pyrazinamide treatment for pleural tuberculosis 5
- A three-drug regimen for pulmonary tuberculosis based on rapid molecular detection of isoniazid resistance 6
Key Findings
The key findings of these studies include:
- The FDC formulation has a better sputum conversion rate at 2 months compared to the conventional separate-drug formulation 3
- Rifampicin plus levofloxacin has a better clinical effect in the treatment of pulmonary TB and can effectively regulate patients' immune functions and inhibit inflammatory reactions 4
- A 6-month therapy with isoniazid and rifampicin is as effective as a treatment regimen of isoniazid, rifampicin, and pyrazinamide for pleural tuberculosis, with fewer adverse effects 5
- A three-drug regimen for pulmonary tuberculosis based on rapid molecular detection of isoniazid resistance is noninferior to the recommended 4-drug regimen 6