Plasmapheresis in Severe Paediatric Neurological Diseases

Plasmapheresis is an extracorporal procedure used for two decades in which the circulating human plasma is exchanged to remove pathogenic antibodies.

We report a case series (n = 7) of pediatric patients (female n = 5) treated with plasmapheresis due to therapy refractory neurological diseases: 3 patients with proven anti-NMDA-AK encephalitis and 4 patients with neurological diseases and suspected autoimmunological genesis (autoimmune encephalitis without detection of antibodies, neuromyelitis optica, multiple sclerosis, seizures with multiple cerebral vasogenic edema).

The patients received a therapy with 7 cycles of plasmapheresis (mean). In the majority of patients the 1.5-fold plasma volume was exchanged with human albumin, sodium chloride (0.9%) and fresh frozen plasma every second day. Plasmapheresis was performed via shaldon catheters (6.5F-12F), which remained in situ for 18 days (mean; range 13d-23d). All patients were treated with methylprednisolone (10–20 mg/kg/d) as well as immunoglobulins (1–3 doses). In half of the patients rituximab (275 mg/m²–720 mg/m²) was administered to maintain the therapies success.

Two out of three patients with anti-NMDA-AK encephalitis showed complete healing (restitutio ad integrum). In 3 (out of 4) patients suffering from initially unclear neurological disease an improvement of the clinical condition could be achieved due to therapy with plasmapheresis. In one patient without therapeutic success, the diagnosis of mitochondriopathia was gentically secured. Side effects of plasmapheresis were observed in three patients with arterial hypotonia and in one case with catheter infection. In one patient we saw an increase of seizures for a short period, most likely due to the removal of anticonvulsant drugs (quantitatively difficult to assess) by plasmapheresis.

Our case series provides an overview of possible neurological treatment indications for plasmapheresis in infants. The best response to therapy was found in patients with anti-NMDA-AK encephalitis, but even without autoantibody detection a therapy trial with plasmapheresis may be justified and successful in presumably autoimmune mediated neurological diseases.