An association of myasthenia gravis with Hashimoto’s thyroiditis in in a patient with a multinodular goitre
- Author:
Mohamed NSF
;
Mohd Zin F
;
Mohd Yusoff SS
- Publication Type:Case Report
- Keywords:
Myasthenia gravis;
autoimmune thyroid disease;
Hashimoto’s thyroiditis;
hashitoxicosis
- From:Malaysian Family Physician
2017;12(2):29-31
- CountryMalaysia
- Language:English
-
Abstract:
Introduction: The association of myasthenia gravis (MG) with other autoimmune diseases
including autoimmune thyroid disease (ATD) is well recognised, although rare. The occurrence
of both diseases can occur in two ways: either disease preceding the other, or concurrently. The
presentation of MG in association with ATD can range from ocular to generalised disease.
Case Summary: A 26-year-old Malay female with persistent hyperthyroidism secondary to
Hashimoto’s thyroiditis in multinodular goitre was diagnosed with generalised MG after 2 years.
She presented with right eye ptosis (ocular) and difficulty in swallowing and chewing (bulbar). The
diagnosis of MG was confirmed by fatigability testing, electromyography and the presence of AChR
antibodies. Her symptoms showed improvement with pyridostigmine (Mestinon) 60 mg 6-hourly.
Her antithyroid drug was tapered down according to her thyroid function test. Throughout a year of
follow-ups, her hyperthyroidism and fatigability symptoms improved with treatment. She was later
counselled for total thyroidectomy and thymectomy.
Conclusion: Myasthenia gravis and hyperthyroidism may present with similar symptoms such as
dysphagia due to neuromuscular weakness or fatigue. When the diseases occur together, one of the
diagnoses may be missed. Therefore, the occurrence of new symptoms in a patient with underlying
ATD should should trigger the early identification of other autoimmune diseases by primary care
doctors.
