Study of the effect of anti-rhGAA antibodies at low and intermediate titers in late onset Pompe patients treated with ERT.

Late onset Pompe disease (LOPD) is a genetic disorder characterized by slowly progressive skeletal and respiratory muscle weakness. Symptomatic patients are treated with enzyme replacement therapy (ERT) with alglucosidase alpha (rhGAA). Although most of ERT treated patients develop antibodies against rhGAA, their influence on clinical progression is not completely known. We studied the impact of anti-rhGAA antibodies on clinical progression of 25 ERT treated patients. We evaluated patients at visit 0 and, after 1 year, at visit 1. We performed several muscle function tests, conventional spirometry and quantitative muscle MRI (qMRI) using 3-point Dixon analysis of thigh muscles at both visits. We also obtained serum samples at both visits and anti-rhGAA antibodies were quantified using ELISA. Antibody titers higher than 1:200 were identified in 18 patients (72%) of our cohort. Seven patients (28%) did not develop antibodies (0 to <1:200), 17 patients (68%) developed low to intermediate titers (1:200 to <1:31,200) and 1 patient (4%) developed high titers (>1:31,200). We analyzed the effect of low and intermediate antibody titers in clinical and radiological progression. There were no differences between the results of muscle function tests, spirometry or fat fraction analyzed using qMRI between patients with and without antibodies groups at baseline. Moreover, antibody titers did not influence muscle function test, spirometry results or qMRI results at year 1 visit. Most of the LOPD patients developed antibodies against ERT that persisted over time at low or intermediate levels. However, antibodies at these low and intermediate titers might not influence clinical response to the drug.

Seronegative and seropositive autoimmune autonomic ganglionopathy (AAG): Same clinical picture, same response to immunotherapy.

Two patients with a syndrome of pandisautonomia with clinical criteria of AAG are provided. Both patients present a similar clinical picture and response to immunosuppressive treatment. One of them has positive antibodies against the ganglionic nicotinic acetylcholine (gAChr) and the other does not. This brief article serves to reflect the spectrum of AAG, at a clinical level, in laboratory tests and in the response to immunotherapy, independently of the presence of positive gAChr antibodies.

Rituximab in treatment-resistant CIDP with antibodies against paranodal proteins.

OBJECTIVE: To describe the response to rituximab in patients with treatment-resistant chronic inflammatory demyelinating polyneuropathy (CIDP) with antibodies against paranodal proteins and correlate the response with autoantibody titers. METHODS: Patients with CIDP and IgG4 anti-contactin-1 (CNTN1) or anti-neurofascin-155 (NF155) antibodies who were resistant to IV immunoglobulin and corticosteroids were treated with rituximab and followed prospectively. Immunocytochemistry was used to detect anti-CNTN1 and anti-NF155 antibodies and ELISA with human recombinant CNTN1 and NF155 proteins was used to determine antibody titers. RESULTS: Two patients had a marked improvement; another patient improved slightly after 10 years of stable, severe disease; and the fourth patient had an ischemic stroke unrelated to treatment and was lost to follow-up. Autoantibodies decreased in all patients after rituximab treatment. CONCLUSIONS: Rituximab treatment is an option for patients with CIDP with IgG4 anti-CNTN1/NF155 antibodies who are resistant to conventional therapies. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that rituximab is effective for patients with treatment-resistant CIDP with IgG4 anti-CNTN1 or anti-NF155 antibodies.

Clinical, electrophysiological and magnetic resonance findings in a family with hereditary neuropathy with liability to pressure palsies caused by a novel PMP22 mutation.

Hereditary neuropathy with liability to pressure palsies (HNPP) is a disorder mainly caused by a 1.5-Mb deletion at 17p11.2-12 (and in some rare cases by point mutations) and clinically associated with recurrent painless palsies. Here, we performed electrophysiological (motor, sensory and terminal latency index), MRI and genetic studies in a family referred for ulnar neuropathy with pain. Surprisingly, we found typical neurophysiological features of HNPP (prolongation of distal motor latencies and diffuse SNCV slowing with significant slowing of motor nerve conduction velocities). Besides, the proband presented conduction block in left ulnar, left median and both peroneal nerves. MRI findings were consistent with an underlying neuropathy. Molecular studies identified a novel frameshift mutation in PMP22 confirming the diagnosis of HNPP. Our data suggest that neurophysiological studies are essential to characterize underdiagnosed HNPP patients referred for peripheral neuropathy. Our experience shows that MRI could be a complementary tool for the diagnosis of these patients.

Neuroleptic malignant syndrome and serotonin syndrome in a female patient: a clinicopathologic case.

We report the case of a 24-year-old female patient who initially developed a neuroleptic malignant syndrome after haloperidol exposure and experienced 6 years later a serotonin syndrome after repeated fluoxetine exposure. The patient did not respond to symptomatic treatment and died in this latter episode. At necropsy, no gross or microscopic changes were seen with conventional histological stains, and immunohistochemical stains were negative. This is the first clinicopathologic case of a patient who experienced both neuroleptic malignant and serotonin syndromes. We speculate that this case argue in favor that both syndromes share some fundamental pathogenetic mechanisms.

Orthostatic hypotension associated with an epidermoid tumor of the IV ventricle.

We report the case of a 32-year-old man with an epidermoid tumor of the fourth ventricle. About 14 years later, he showed a tumor recurrence which was removed. After this procedure the patient complained of presyncopal and syncopal crisis while attempting to stand or walk. On examination, severe orthostatic hypotension was confirmed and autonomic tests were abnormal. The brain MRI showed a tetraventricular hydrocephalus predominating in the fourth ventricle. A ventriculo-peritoneal shunt was performed, and after surgery the orthostatic intolerance improved. We believe that hydrocephalus has probably been a contributory factor to orthostatic hypotension, and suggest expanding testing for dysautonomia in patients with hydrocephalus.

Restless legs syndrome in Parkinson's disease.

The present study explores the frequency of RLS in PD and focuses on the clinical differences between patients with and without restless legs syndrome (RLS). A cross-sectional study was designed, comprising 114 patients diagnosed with PD. Those patients positive for RLS were assessed for intensity of the syndrome (IRLS). We compared the clinical characteristics of the patients with and without RLS, using specific scales: Unified Parkinson's Disease Rating Scale (UPDRS I-IV), quality of life (Parkinson's Disease Questionnaire, PDQ 39), sleep symptoms (Parkinson's Disease Sleep Scale, PDSS), and diurnal hypersomnia (Epworth Sleepiness Scale). Twenty-five patients (21.9%) out of a total of 114 subjects diagnosed with PD met the RLS diagnostic criteria. RLS was more frequent in women (68%). The patients with RLS showed poorer scores on the PDSS (PD-RLS+: 102.4 +/- 15.1 vs PD-RLS-: 113.2 +/- 16.4) (P = 0.005) and in the bodily discomfort dimension of the PDQ-39 (PD-RLS+ 6.1 +/- 3.4 vs PD-RLS- 3.8 +/- 2.6) (P = 0.002). Analysis of the subscales of the PDSS showed significant differences (P < 0.001) between both groups of patients in items 4 and 10, and to a lesser degree in items 5 (P = 0.01) and 11 (P = 0.02) There was no increased incidence of diurnal hypersomnia in the group of patients with RLS. There were no differences in the rest of the variables. RLS is frequent in patients with PD, though this condition doesn't apparently affect quality of life or lead to an increased presence of diurnal hypersomnia. It would be advisable to validate the diagnostic criteria of RLS in this specific group of patients.

Use of ziprasidone in parkinsonian patients with psychosis.

Twelve patients with Parkinson disease and psychosis were included in an open-label 12-week trial of ziprasidone. Two patients withdrew from the treatment because of adverse effects. The remaining 10 patients reported a significant improvement in psychiatric symptoms. Altogether, there was no deterioration of motor symptoms (UPDRS III score: basal 40.4 +/- 11.1, first month 41.1 +/- 10.8; final visit, 37.7 +/- 13.3). Two patients (20%) suffered a slight deterioration in motor symptoms and another patient suffered deterioration of gait. No analytic alterations or serious adverse effects that could limit the use of ziprasidone were observed. Although controlled trials are needed, the findings suggest that ziprasidone may be effective in parkinsonian patients with psychosis.