Chronic inflammatory demyelinating polyneuropathy (CIDP), Myasthenia gravis and Hashimoto thyroiditis – a very rare coincidence in a 17-year-old patient

Guillain Barré syndrome (GBS), Myasthenia gravis (MG), and Hashimoto thyroiditis (HT) are each in itself very well-known autoimmune diseases. The occurrence of MG and GBS in the same patient is very rare reported and difficult to diagnose, because both diseases might present with the same symptoms and leading to a very severe muscle weakness.

We report the case of a 15-year-old patient, who was presented with the typical clinical symptoms of a GBS triggered by a viral infection 4 months before. At first examination in our hospital 6 months later associated laboratory findings in CSF (elevated protein 73 mg%), as well as neurophysiological abnormalities (axonal and demyelinating neuropathy) were shown. After 12 months of treatment with intravenous immunoglobulins once a month and very slow improvement of his muscle strength, he developed an unilateral partial oculomotorius paresis. A steroid pulse was given with slightly improvement of the ocular symptoms. During the next months, the patient showed a distinct deterioration of his muscle strength with limited ability to walk. Also, he developed a very severe bilateral ophthalmoplegia and ptosis, which were more marked toward the second half of the day.

Laboratory investigations showed a presence of autoantibodies against the thyroid gland and ultrasound abnormalities that confirmed the diagnosis of an HT. Furthermore, we found autoantibodies against acetylcholine receptors so that we were able to verify the expected diagnosis of a myasthenia gravis. So, we started a treatment with pyridostigmine, associated with an immunosuppressive therapy consisting of azathioprine and prednisolone.

The coincidence of a chronic inflammatory demyelinating polyneuropathy (CIDP), Hashimoto thyroiditis and Myasthenia gravis is very rarely documented in the literature. In case of a worsening of symptoms of a CIDP, despite the supplementation of parenteral immunoglobulins therapy, one should be aware of the occurrence of an MG.