Case report: Seropositive myasthenia gravis complicated by limbic encephalitis positive for antibodies to AMPAR and Lgi1.

Objectives: Autoantibodies to the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and leucine-rich glioma-inactivated 1 (Lgi1) are associated with autoimmune encephalitis. We described an acetylcholine receptor (AChR)-positive patient with myasthenia gravis who developed limbic encephalitis with antibodies to AMPAR and Lgi1. Methods: A single-case report with detailed, prospective clinical and biomarker data including serial laboratory testing and histopathology. Results: A 49-year-old woman was diagnosed with anti-AChR antibody-positive generalized myasthenia gravis in 1983. After 9 months of the removal of thymoma in 1984, she developed influenza-like symptoms and then symptoms of limbic encephalitis. Retrospective analysis of serum showed high concentrations of anti-AMPAR and lower concentrations of anti-Lgi1 antibodies. Cerebral CT was normal, EEG showed bifrontal dysrhythmia, and CSF showed mild pleocytosis. Immuno-histochemical examination of the thymoma confirmed staining for Glur2, a subunit of AMPAR. The patient recovered with mild sequelae, but low levels of anti-AMPAR and anti-Lgi1 antibodies were detectable for over 25 years subsequently. Discussion: This case confirms earlier reports of AMPAR-associated autoimmune encephalitis co-occurring with thymoma and myasthenia gravis and is unique in its observational length. It shows, moreover, that antibodies to AMPAR and Lgi1 can persist despite clinical recovery.

[A man in his fifties with near-syncope episodes and persistent dizziness]. / En mann i 50-årene med nærbesvimelser og vedvarende svimmelhet.

BACKGROUND: A previously healthy male patient in his fifties presented with subacute onset of severe, diffuse dysautonomia with orthostatic hypotension as the main symptom. A lengthy interdisciplinary workup revealed a rare condition. CASE PRESENTATION: Over the course of a year, the patient was twice admitted to the local department of internal medicine because of severe hypotension. Testing showed severe orthostatic hypotension with normal cardiac function tests and no apparent underlying cause. On referral to neurological examination, symptoms of a broader autonomic dysfunction were discovered, with symptoms of xerostomia, irregular bowel habits, anhidrosis and erectile dysfunction. The neurological examination was normal, except for bilateral mydriatic pupils. The patient was tested for ganglionic acetylcholine receptor (gAChR) antibodies. A strong positive result confirmed the diagnosis of autoimmune autonomic ganglionopathy. There were no signs of underlying malignancy. The patient received induction treatment with intravenous immunoglobulin and later maintenance treatment with rituximab, resulting in significant clinical improvement. INTERPRETATION: Autoimmune autonomic ganglionopathy is a rare but likely underdiagnosed condition, which may cause limited or widespread autonomic failure. Approximately half of the patients have ganglionic acetylcholine receptor antibodies in serum. It is important to diagnose the condition as it can cause high morbidity and mortality, but responds to immunotherapy.

Syphilis with diplopia. / Syfilis med dobbeltsyn.

BACKGROUND: Syphilis is a sexually transmittable infectious disease caused by the spirochaete Treponema pallidum, which classically causes symptoms in three stages. CASE PRESENTATION: A previously healthy male in his thirties was admitted to our department after suffering from diplopia and unilateral ptosis for two days. Clinical examination revealed a left-sided oculomotor palsy with an ipsilateral ptosis. Supplementary cerebral computer tomography with angiography and magnetic resonance imaging was normal except for lymphadenopathy in the neck and mediastinum. As the patient was homosexual, we chose to test for HIV. The doctor on duty, being from Belarus where syphilis was recognised as endemic during her studies, also screened for syphilis. The HIV test was negative, while the syphilis test was positive. Lumbar puncture showed moderate pleocytosis and positive serology for syphilis, confirming the diagnosis of neurosyphilis. The patient recovered fully after a course of penicillin. INTERPRETATION: Even though syphilis remains uncommon in Norway, the incidence has been increasing in recent decades, especially in male homosexual communities. Patients may subsequently present with a diversity of symptoms.