Paper II — 2022 October (Supplementary) (2010 Scheme) — Q2

Paper II

2022 October (Supplementary) (2010 Scheme)

Question

Mr. Madhavan aged 40 yrs developed pulmonary tuberculosis and he was given treatment with first line anti-tubercular agents. After one month of regular treatment, he reported back with complaints of visual disturbances and difficulty in following traffic signals.  Which drug is responsible for his complaints  What is the mechanism of its action in tuberculosis  What is MDR-TB  How will you manage MDR-TB (1+2+1+2)

Q26 marksEssays★✓

Answer

Drug responsible: Ethambutol — its dose-related optic/retrobulbar neuritis presents with reduced visual acuity and characteristically red-green color blindness, exactly matching the difficulty following traffic signals described here.

Mechanism of action in tuberculosis Ethambutol → inhibits arabinosyl transferase → blocks arabinogalactan synthesis (a mycobacterial cell wall component) → bacteriostatic action. Included in the intensive phase primarily to protect the other three drugs from resistance emergence, rather than for potent independent bactericidal activity.

What is MDR-TB Multidrug-resistant tuberculosis — M. tuberculosis resistant to at least isoniazid and rifampicin, the two most potent first-line agents, requiring a longer, more toxic, second-line regimen with substantially poorer treatment outcomes.

Management of MDR-TB

• Confirm resistance pattern by drug susceptibility testing before regimen selection
• Combination of at least 4-5 effective second-line drugs, guided by susceptibility results — typically including a later-generation fluoroquinolone (levofloxacin, moxifloxacin), an injectable agent (amikacin, kanamycin) or newer oral agent (bedaquiline, linezolid), plus other second-line agents
• Prolonged treatment duration (18-24 months historically, shorter regimens now available in select cases)
• Directly observed therapy to ensure adherence and prevent further resistance amplification
• Close monitoring for the greater toxicity burden of second-line agents

Related Concepts

1. 1Antitubercular Drugs

Other Years Asked

1. 1A 45-year-old male factory worker weighing 60 kg reports to the hospital with cough and expectoration, mild chest pain, weakness and fatigue for the last one month. In addition, he has developed low grade fever for the last one week. He gives history of having suffered from tuberculosis of the lung one year back for which he took treatment from the hospital and became all right in 2 months. He stopped taking the medicines after another 1 month, though he was told by the doctor to continue treatment. The sputum was found to be positive for AFB and X-ray chest showed a 5 cm cavitary lesion in the right middle lobe and fibrotic changes in the upper lobe. He was diagnosed to be a previously treated and defaulted patient of pulmonary tuberculosis.2024 December (Supplementary) (2019 Scheme)Essay · 10 marks
2. 2(2022 July (Supplementary) (2019 Scheme)Short Essay · 8 marks
3. 3A 45-year-old nurse complaining of evening rise of temperature since a month with loss of appetite and weight is presenting with sputum positive for AFB and diagnosis for primary pulmonary tuberculosis. (2023 March (Supplementary) (2010 Scheme)Essay · 6 marks
4. 4Describe the mechanism of action, adverse effects and uses of Rifampicin.2025 March (Supplementary (SAY)) (2019 Scheme)Short Essay · 6 marks
5. 5What is the pharmacological basis for the use of pyridoxine along with isoniazid.2025 March (Supplementary (SAY)) (2019 Scheme)Short Answer · 4 marks
6. 6Treatment of Pulmonary tuberculosis2024 June (Supplementary) (2019 Scheme)Short Answer · 4 marks
7. 7Rifampicin2016 October (Supplementary) (2010 Scheme)Short Note · 3 marks
8. 8Isoniazid (INH)2024 August (Supplementary) (2010 Scheme)Short Note · 3 marks
9. 9Rifampicin.2014 September (Supplementary) (2010 Scheme)Short Note · 3 marks
10. 10Therapeutic uses and adverse effects of rifampicin.2013 September (Supplementary) (2010 Scheme)Short Note · 3 marks
11. 11Rifampicin.2024 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
12. 12Pyridoxine should be given with Isoniazid.2024 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
13. 13Treatment of multi drug resistant tuberculosis2016 February (2010 Scheme)Short Answer · 1 mark
14. 14INH and pyridoxine2021 February (Supplementary) (2010 Scheme)Short Answer · 1 mark
15. 15Isoniazid hydrazide2019 July (Supplementary) (2010 Scheme)Short Answer · 1 mark
16. 16Chemoprophylaxis in tuberculosis2016 October (Supplementary) (2010 Scheme)Short Answer · 1 mark
17. 17Rifampicin2021 December (Supplementary) (2010 Scheme)Short Answer · 1 mark
18. 18Brucellosis.2015 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
19. 19Rifampicin2022 May (Supplementary) (2010 Scheme)Short Answer · 1 mark
20. 20Treatment of MDR-TB2017 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
21. 21Mechanism of action of INH2017 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
22. 22Multidrug therapy for tuberculosis2020 February (Supplementary) (2010 Scheme)Short Answer · 1 mark
23. 23First line anti tubercular drugs2014 March (2010 Scheme)Short Answer · 1 mark
24. 24Streptomycin2021 December (Supplementary) (2010 Scheme)Short Answer · 1 mark
25. 25Pyridoxine with isoniazid2021 May (Supplementary) (2010 Scheme)Short Answer · 1 mark
26. 26Mention four adverse effects of rifampicin2013 April (2010 Scheme)Short Answer · 1 mark
27. 27Pyridoxine (Vitamin B6) with Isoniazid (INH) in Antitubercular therapy.2023 July (Supplementary) (2010 Scheme)Short Answer · 1 mark