رجل عمره ٤٧ سنة على علاج السل منذ شهر، ويأخذ ريفامبيسين وإيزونيازيد وبيرازيناميد وإيثامبوتول. جاء للمتابعة وعنده عدة شكاوى بسيطة. وظائف الكلى طبيعية. أي عرض يجب أن يبلغ عنه فوراً؟

A 47-year-old man has been on TB treatment for a month with rifampicin, isoniazid, pyrazinamide and ethambutol. At follow-up he has several minor complaints. Renal function is normal. Which symptom must be reported immediately?

1. Blurred vision or poor colour discrimination
2. Mild stomach upset after the dose
3. Increased appetite and weight gain
4. Orange discolouration of urine and tears

Answer: A) Blurred vision or poor colour discrimination. Ethambutol can cause optic neuritis with reduced acuity or colour-vision loss. Vision is checked before and during treatment and the drug stopped if symptoms appear.