Treatment of progressive encephalomyelitis with rigidity and myoclonic jerks with rituximab: a case report

Progressive encephalomyelitis with rigidity: A Taiwanese case and review of literature

INTRODUCTION

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a rare disorder. However, the outcome is still variable with different serological and tumor associations, and the elements to good response with less relapse is yet to be elucidated.

METHOD

We present a case and obtain a literature review of patients with PERM and make comparisons based on different serological groups. We also analyze patients with idiopathic PERM that had detailed medical records.

RESULTS

81 patients were collected and analyzed. The largest group were glycine receptor-antibody (GlyR-Ab)-positive (70%), and the seropositive-GlyR-Ab-negative group had better response to immunotherapy. Malignancy can occur up to 2 years from the presentation of PERM. Among the 18 cases with detailed records, the patients who had good outcome initiate immunotherapy within 2 months from presentation. 9 of the 12 patients who experienced no relapse had non-steroid immunotherapy. The maximal interval time of relapse was 24 months.

CONCLUSION

We recommend tumor surveillance up to 2 years in patients with PERM and early administration of immunotherapies and maintain with non-steroid immunotherapy with or without oral corticosteroid for a minimum of 2 years to reduce the risk of relapse in GlyR-Ab-positive patients.

Progressive Encephalomyelitis With Rigidity and Myoclonus With Thymoma: A Case Report and Literature Review

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is part of the variant type of the Stiff Person Syndrome (SPS) and is a rare neurological disease. We report here a patient with PERM who had thymoma and was positive for anti-glutamic acid decarboxylase (anti-GAD) antibodies. Her symptoms improved after treatment with hormones and gamma globulin. We also summarized the literature review of patients with PERM accompanied by tumors reported.

A case report of rigidity and recurrent lower limb myoclonus: progressive encephalomyelitis rigidity and myoclonus syndrome, a chameleon

BACKGROUND

Progressive encephalomyelitis with rigidity and myoclonus (PERM) syndrome is a rare neurological condition. Its clinical characteristics include axial and limb muscle rigidity, myoclonus, painful spasms and hyperekplexia. Diagnosis of this disease can be very challenging and optimal long-term treatment is unclear.

CASE PRESENTATION

We report a case of a 62 year old patient admitted for repetitive myoclonus and rigidity in the lower limbs progressing since 10 years, associated with a fluctuating encephalopathy requiring stays in Intensive Care Unit. Multiple diagnostics and treatment were proposed, unsuccessfully, before the diagnosis of PERM syndrome was established. In association with the clinical presentation, a strong positive result for GAD (glutamic acid decarboxylase) antibodies lead to the diagnosis of PERM syndrome.

CONCLUSIONS

PERM syndrome is a rare disease and its diagnosis is not easy. Once the diagnosis is established, the correct treatment should follow and could be lifesaving, regardless of a delayed diagnosis. Maintenance of long-term oral corticotherapy is suggested to prevent relapses.

[A case of progressive encephalomyelitis with rigidity and myoclonus associated with anti-GAD, anti-glycine receptor and anti-GM1 antibodies]

A 62-year-old woman with one-year history of type 1 diabetes mellitus was admitted to our hospital with progressive weakness in the lower extremities and urinary dysfunction following high fever. On admission, she had rigidity and myoclonus in the upper extremities with sensory ataxia. Cerebrospinal fluid examination revealed mild pleocytosis and oligoclonal band. Glutamic acid decarboxylase (GAD) antibodies were detected at high titer in serum, but antibodies to glycine receptor (GlyR), thyroid peroxidase, mitochondrial M2, and GM1 were also detected. She was diagnosed with progressive encephalomyelitis with rigidity and myoclonus (PERM), which probably developed on the basis of polyglandular autoimmune syndromes. The clinical symptoms began to improve after initiation of intravenous high-dose methylprednisolone. Muscle weakness might be related to GM1 antibodies. This is the first report of PERM, in which GM1 antibodies were detected with GAD and GlyR antibodies.

Stiff person syndrome: advances in pathogenesis and therapeutic interventions

Stiff person syndrome (SPS) varies from mild to severe, but if untreated it can be progressive and disabling. Although progress has been made in understanding and treating SPS, the disease remains underdiagnosed, delaying treatment. Antibodies against glutamic acid decarboxylase provide an excellent diagnostic marker, but their role in disease pathogenesis is uncertain. Research focused on identifying new autoantigens has provided evidence that gamma-aminobutyric acid (GABA)(A) receptor-associated protein (GABARAP), a 14-kD protein localized at the postsynaptic regions of GABAergic synapses, is an antigenic target. Circulating anti-GABARAP antibodies that inhibit GABA(A) receptor expression on GABAergic neurons have been found in up to 65% of SPS patients. The impairment of GABAergic pathways and reduction of brain GABA results in clinical manifestations of stiffness, spasms, and phobias. Increased awareness of SPS among practicing physicians is necessary to recognize the disease early and prevent permanent disability. Most patients with SPS respond to GABA-enhancing drugs, but the high doses required cause unacceptable adverse effects. The disease clearly responds to intravenous immunoglobulin, but repeated infusions are needed to maintain response. New immunomodulating agents are being explored to treat difficult cases and to induce long-lasting remissions.