Plasma exchange for anti GAD associated non paraneoplastic limbic encephalitis.

Limbic encephalitis (LE) is a neurological syndrome usually presenting in a paraneoplastic form. Recently many cases were reported with no concurring neoplasia, presenting with specific antibodies for voltage-gated potassium channel or for neuronal membrane antigens. Anti-glutamic acid decarboxylase (GAD) antibodies act against GABAergic receptors of the central nervous system. These antibodies were found in coeliac disease serum and in neurologic patients. We are reporting a case of a 21-year-old coeliac woman manifesting complex multiple-daily partial drug-resistant seizures for 7 years. The diagnosis was of a non paraneoplastic limbic encephalitis, unresponsive to high dose cortisone and IGIV infusion. The use of therapeutic plasma exchange (TPE) has resulted in an improvement in symptoms with quite a long disease-free period of time. When the frequency of the procedures was decreased, seizures appeared again and, after suspension of TPE, the clinical status worsened. The role of TPE in the treatment of LE still has to be defined.

Non-paraneoplastic limbic encephalitis associated with anti-glutamic acid decarboxylase antibodies.

Limbic encephalitis (LE) is a neurological syndrome that may present in association with cancer, infection, or as an isolate clinical condition often accompanying autoimmune disorders. Here we have characterized the clinical and laboratory features of two patients presenting with subacute onset, and chronic evolution, of anterograde amnesia and drug-resistant epilepsy associated with thyroid autoimmunity and in absence of tumoral pathology despite long follow-up. Antibodies against onconeural antigens, voltage gated potassium channel and glutamate receptors, which may accompany paraneoplastic as well as non-paraneoplastic LE, were negative. However, biochemical studies showed high titers, and sustained intrathecal synthesis, of antibodies directed against neuronal glutamic acid decarboxylase (GAD). In one patient, plasma exchange determined a dramatic improvement of the neurological deficits along with the decrease of autoantibodies.

Plasmapheresis therapy in pemphigus vulgaris and bullous pemphigoid.

Blistering dermatitises are characterized by the presence of blisters that begin owing to acantholysis (intraepidermic blister) such as pemphigus vulgaris (PV) or owing to dermoepidermic detachment (subepidermic blister) such as bullous pemphigoid (BP). Both diseases are autoimmune pathologies characterized by the presence of autoantibodies against specific adhesion molecules of the skin and mucous membranes. PV, in which oral lesions are always present, has a progressive course that, if the disease is not treated, nearly always brings to death from sepsis within a few years. In BP, oral lesions are rare and the disease, that is most frequent in older individuals, has a chronic course with spontaneous remissions. Systemic corticosteroids and immunosuppressants are the mainstay of treatment of these two diseases. Although this therapy had reduced the mortality of the two pathologies it is associated with serious side effects. To reduce the corticosteroids dose and to improve the symptomatology in resistant therapy cases, we treated five patients with several procedures of plasma exchange. Four patients were affected by BP and one by PV. Their disease severity at onset of plasmapheresis ranged from mild to severe. One of 5 patients suffered a plasmapheresis side effect. All patients responded with complete remission of symptomatology and had a prednisone dosage reduction until 70%. Plasmapheresis is an effective treatment for PV and BP patients who have been unresponsive to conventional therapy, for those for whom conventional drugs are contraindicated, for those who show severe clinical manifestations and for those who need high doses of corticosteroids and immunosuppressants to keep the disease under control.