A 40-year-old man presents with ptosis, diplopia, and fatigable proximal limb weakness worse in the evening. Edrophonium (Tensilon) test is positive. Anti-AChR antibodies are positive. CT chest reveals a 3 cm anterior mediastinal mass. The NEXT most important step in management after starting pyridostigmine is:
- A High-dose oral prednisolone immediately
- B Thymectomy (surgical removal) ✓
- C IVIG infusion 2 g/kg over 5 days
- D Rituximab infusion
Explanation
An anterior mediastinal mass in a patient with seropositive generalised MG indicates thymoma, which is present in 15% of MG patients. Thymoma-associated MG requires thymectomy not only for potential oncological cure but because thymectomy improves long-term MG outcomes (MGTX trial 2016 confirmed benefit in non-thymomatous MG as well, supporting thymectomy in all generalised seropositive MG aged 18-65). Immediate high-dose steroids can precipitate myasthenic crisis and should be introduced cautiously. IVIG is used for acute exacerbations or pre-surgical optimisation. Rituximab is for MuSK-antibody MG refractory to standard therapy.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.