Assessment of the reproducibility of oligoclonal IgM band detection for its application in daily clinical practice

BACKGROUND

The presence of oligoclonal IgM bands (OCMB) in cerebrospinal fluid (CSF) is an unfavourable prognostic marker in multiple sclerosis. There is no commercial test to investigate OCMB status. However, a sensitive and specific isoelectrofocusing (IEF) and western blot method was described. We aimed to study the inter-centre reproducibility of this technique, a necessary condition for a reliable test to be incorporated into clinical practice.

METHODS

The presence of OCMB was analysed by IEF and western blot with prior reduction of pentameric IgM. We assayed the reproducibility of this test in a blinded multicentre study performed in 13 university hospitals. Paired-CSF and serum samples from 52 neurological patients were assayed at every centre.

RESULTS

Global analysis rendered a concordance of 89.8% with a kappa value of 0.71.

CONCLUSION

These data indicate that OCMB detection by means of IEF and western blot with IgM reduction shows a good interlaboratory reproducibility and thus can be used in daily clinical setting.

Spanish consensus on the use of natalizumab (Tysabri®)-2013

INTRODUCTION

Natalizumab treatment has been shown to be very efficacious in clinical trials and very effective in clinical practice in patients with relapsing-remitting multiple sclerosis, by reducing relapses, slowing disease progression, and improving magnetic resonance imaging patterns. However, the drug has also been associated with a risk of progressive multifocal leukoencephalopathy (PML). The first consensus statement on natalizumab use, published in 2011, has been updated to include new data on diagnostic procedures, monitoring for patients undergoing treatment, PML management, and other topics of interest including the management of patients discontinuing natalizumab.

MATERIAL AND METHODS

This updated version followed the method used in the first consensus. A group of Spanish experts in multiple sclerosis (the authors of the present document) reviewed all currently available literature on natalizumab and identified the relevant topics would need updating based on their clinical experience. The initial draft passed through review cycles until the final version was completed.

RESULTS AND CONCLUSIONS

Studies in clinical practice have demonstrated that changing to natalizumab is more effective than switching between immunomodulators. They favour early treatment with natalizumab rather than using natalizumab in a later stage as a rescue therapy. Although the drug is very effective, its potential adverse effects need to be considered, with particular attention to the patient's likelihood of developing PML. The neurologist should carefully explain the risks and benefits of the treatment, comparing them to the risks of multiple sclerosis in terms the patient can understand. Before treatment is started, laboratory tests and magnetic resonance images should be available to permit proper follow-up. The risk of PML should be stratified as high, medium, or low according to presence or absence of anti-JC virus antibodies, history of immunosuppressive therapy, and treatment duration. Although the presence of anti-JC virus antibodies is a significant finding, it should not be considered an absolute contraindication for natalizumab. This update provides general recommendations, but neurologists must use their clinical expertise to provide personalised follow-up for each patient.

[Bone marrow stem cell transplantation in amyotrophic lateral sclerosis: technical aspects and preliminary results from a clinical trial]

Patients with amyotrophic lateral sclerosis (ALS) experience progressive and irreversible paralysis as a result of the continued loss of motor neurons, which leads to death in less than five years. To date, there is no treatment that can change the progression of this disease. Bone marrow stem cells have shown neural regenerative and neural repairing properties. Specifically, our group showed in a murine model of the disease that these cells, when injected in the spinal cord, can rescue motor neurons through the secretion of GDNF. Based on these results, we designed a phase I/II clinical trial for the purpose of demonstrating the viability of the intraspinal injection of autologous bone marrow mononuclear cells in patients with bulbar onset ALS, with an evolution between 6 and 36 months, with a forced vital capacity (FVC) 50% and T90 29%. This article describes the technique for extracting 60 mL of bone marrow used for the intervention, processing it by density gradient, and the neurosurgical technique used for implanting it. After 6 months of follow-up, the few adverse events reported in the first seven patients included seem to show that the procedure is safe and viable. Most of these patients, including two with a rapid deterioration, have stabilized the progression of their FVC and the neurologic scales measured. The data obtained so for seem to justify the design of new trials more oriented toward the efficacy of the procedure.

[Delayed diagnosis of phenylketonuria as the cause of mental retardation in an adolescent]

INTRODUCTION

The hyperphenylalaninemias (HFA) form a diverse group of recessive autosomic disorders. They are caused by defects in the hepatic system for hydroxylation of the amino acid phenylalamine to tyrosine. The estimated incidence is approximately 10 cases per 100,000 live births. Children with this metabolic disorder may present with varied neurological symptoms. Control of plasma levels, so that they are more normal as soon as possible after birth, significantly prevents mental retardation and other neuropsychological dysfunction. For this reason HFA has been included in neonatal screening. However, some patients are not detected on screening. When they are adults, these patients pose problems of diagnosis for neurologists who attend adults.

CLINICAL CASE

We describe an adolescent with mental and linguistic retardation, in whom neonatal screening to rule out metabolic defects was normal. At the age of 15, the phenylalanine in blood and urine were found to be raised. On cerebral magnetic resonance changes typical of pheynylketonuria (PKU) were seen.

CONCLUSIONS

The HFA should be considered as causes of cerebral dysfunction in adults, since in spite of neonatal screening, false negatives may occur. We describe a clinical case and consider different forms of hyperphenylaleninemias. Their diagnosis and treatment.