Kappa free light chains is a valid tool in the diagnostics of MS: A large multicenter study.

OBJECTIVE: To validate kappa free light chain (KFLC) and lambda free light chain (LFLC) indices as a diagnostic biomarker in multiple sclerosis (MS). METHODS: We performed a multicenter study including 745 patients from 18 centers (219 controls and 526 clinically isolated syndrome (CIS)/MS patients) with a known oligoclonal IgG band (OCB) status. KFLC and LFLC were measured in paired cerebrospinal fluid (CSF) and serum samples. Gaussian mixture modeling was used to define a cut-off for KFLC and LFLC indexes. RESULTS: The cut-off for the KFLC index was 6.6 (95% confidence interval (CI) = 5.2-138.1). The cut-off for the LFLC index was 6.9 (95% CI = 4.5-22.2). For CIS/MS patients, sensitivity of the KFLC index (0.88; 95% CI = 0.85-0.90) was higher than OCB (0.82; 95%CI = 0.79-0.85; p < 0.001), but specificity (0.83; 95% CI = 0.78-0.88) was lower (OCB = 0.92; 95% CI = 0.89-0.96; p < 0.001). Both sensitivity and specificity for the LFLC index were lower than OCB. CONCLUSION: Compared with OCB, the KFLC index is more sensitive but less specific for diagnosing CIS/MS. Lacking an elevated KFLC index is more powerful for excluding MS compared with OCB but the latter is more important for ruling in a diagnosis of CIS/MS.

Neurofilament light chain levels in pregnant multiple sclerosis patients: a prospective cohort study.

BACKGROUND AND PURPOSE: Neurofilament light chain is a cytoskeletal protein of neurons. Its levels are increasingly recognized as measures of neuroaxonal damage. The aim of this study was to explore serum neurofilament light chain (sNfL) levels in multiple sclerosis (MS) patients and healthy controls during pregnancy and puerperium. METHODS: This was a prospective, longitudinal, single-center study. sNfL concentration was assessed using a highly sensitive single-molecule array during pregnancy and in puerperium, in a cohort of 39 pregnant patients with relapsing multiple sclerosis (P-MS). Twenty-one healthy pregnant women (HPW) served as a control group. Eight P-MS suffered relapses during pregnancy (P-MS-R) in the first or second trimesters. RESULTS: No differences in pregnancy and delivery data were observed between P-MS and HPW. P-MS showed higher sNfL values than HPW in the first trimester, independently of the presence (P = 0.002) or not (P = 0.02) of relapses during pregnancy. However, in the third trimester, only P-MS-R showed higher sNfL values than HPW (P = 0.001). These differences extended to the puerperium, where P-MS-R showed higher sNfL values than those with no relapses during gestation (P = 0.02). CONCLUSION: These data strongly suggest that sNfL levels reflect MS activity during pregnancy. Additionally, the absence of relapses during pregnancy may have a beneficial effect on neurodegeneration during puerperium.

Low cytomegalovirus seroprevalence in early multiple sclerosis: a case for the 'hygiene hypothesis'?

BACKGROUND AND PURPOSE: Cytomegalovirus (CMV) infection has recently been associated with a lower multiple sclerosis (MS) susceptibility, although it remains controversial whether it has a protective role or is merely an epiphenomenon related to westernization and early-life viral infections. We aimed to evaluate whether CMV serostatus may differ in patients with early MS as compared with patients with non-early MS, analyzing the putative association of this virus with MS clinical course and humoral immune responses against other herpesviruses. METHODS: Multicentric analysis was undertaken of 310 patients with MS (early MS, disease duration ≤5 years, n = 127) and controls (n = 155), evaluating specific humoral responses to CMV, Epstein-Barr virus and human herpesvirus-6, as well as T-cell and natural killer (NK)-cell immunophenotypes. RESULTS: Cytomegalovirus seroprevalence in early MS was lower than in non-early MS or controls (P < 0.01), being independently associated with disease duration (odds ratio, 1.04; 95% confidence interval, 1.01-1.08, P < 0.05). CMV+ patients with MS displayed increased proportions of differentiated T-cells (CD27-CD28-, CD57+, LILRB1+) and NKG2C+ NK-cells, which were associated with a lower disability in early MS (P < 0.05). CMV+ patients with early MS had an age-related decline in serum anti-EBNA-1 antibodies (P < 0.01), but no CMV-related differences in anti-human herpesvirus-6 humoral responses. CONCLUSIONS: Low CMV seroprevalence was observed in patients with early MS. Modification of MS risk attributed to CMV might be related to the induction of differentiated T-cell and NK-cell subsets and/or modulation of Epstein-Barr virus-specific immune responses at early stages of the disease.

Cognitive impairment in early stages of multiple sclerosis is associated with high cerebrospinal fluid levels of chitinase 3-like 1 and neurofilament light chain.

BACKGROUND AND PURPOSE: Chitinase 3-like 1 (CHI3L1) and neurofilament light chain (NF-L) are promising biomarkers of disability in multiple sclerosis (MS). However, their role in cognitive dysfunction remains elusive. Here, we aimed to correlate cerebrospinal fluid (CSF) levels of CHI3L1 and NF-L with cognitive status in MS. METHODS: Fifty one recently diagnosed patients were cognitively evaluated and CSF was collected. Levels of CHI3L1 and NF-L were determined by ELISA. Spearman's partial correlation coefficient was performed. RESULTS: After adjusting cognitive scores by age, anxiety and EDSS, association was detected between CHI3L1 levels and Trail Making Test A (rs = 0.348; p = 0.016) and between NF-L levels and Word List Generation (rs = -0.324; p = 0.025). CONCLUSION: High levels of CSF CHI3L1 and NF-L are associated with cognitive impairment in the early phases of MS.

Clinical usefulness of prognostic biomarkers in optic neuritis.

BACKGROUND AND PURPOSE: Different biological and radiological biomarkers predict clinical conversion to multiple sclerosis (MS) after a clinically isolated syndrome (CIS). The aim was to explore their role in predicting the outcome of patients with optic neuritis (ON), a CIS considered to have a benign prognosis. METHODS: Sixty-eight consecutive ON patients were followed prospectively. Magnetic resonance imaging (MRI) and cerebrospinal fluid studies including oligoclonal immunoglobulin G (IgG) bands (OCGBs), lipid-specific oligoclonal IgM bands (LS-OCMBs) and neurofilament light chain quantification were performed at disease onset. Conversion to clinically definite MS (CDMS) was monitored. RESULTS: The mean time of follow-up of our series was 46.4 months. Twenty-five patients (36.7%) developed CDMS during follow-up. Neurofilament light chain levels did not predict clinical conversion. By contrast, an abnormal MRI increased the risk of CDMS [hazard ratio (HR) 12.5, P = 0.013]. The clearest association was found in patients with more than three T2 lesions. OCGBs also predicted the onset of CDMS (HR 21.3, P = 0.003) and LS-OCMBs were associated with a shorter time to CDMS (HR = 116.6, P < 0.001). CONCLUSIONS: Magnetic resonance imaging and OCGBs predicted conversion to CDMS after an ON episode. In addition, LS-OCMBs identified the ON patients more likely to develop MS early. These results, applicable to the everyday clinical setting, may be of interest for therapeutic decisions.

Comparison of oral fluid collection methods for the molecular detection of hepatitis B virus.

BACKGROUND: This study aims to compare the efficiency of four oral fluid collection methods (Salivette, FTA Card, spitting and DNA-Sal) to detect HBV DNA by qualitative PCR. MATERIALS AND METHODS: Seventy-four individuals (32 HBV reactive and 42 with no HBV markers) donated serum and oral fluid. In-house qualitative PCR to detect HBV was used for both samples and commercial quantitative PCR for serum. RESULTS: HBV DNA was detected in all serum samples from HBV-infected individuals, and it was not detected in control group. HBV DNA from HBV group was detected in 17 samples collected with Salivette device, 16 samples collected by FTA Card device, 16 samples collected from spitting and 13 samples collected by DNA-Sal device. Samples that corresponded to a higher viral load in their paired serum sample could be detected using all oral fluid collection methods, but Salivette collection device yielded the largest numbers of positive samples and had a wide range of viral load that was detected. CONCLUSION: It was possible to detect HBV DNA using all devices tested, but higher number of positive samples was observed when samples were collected using Salivette device, which shows high concordance to viral load observed in the paired serum samples.

Knowledge, attitude and behaviour regarding hepatitis C virus infection amongst Brazilian dental students.

AIM: Dental health professionals, including dental students, are at high risk of exposure to infection with the hepatitis C virus (HCV) through occupational percutaneous injuries and eye exposure. Further, fear of HCV infection is associated with discriminatory attitudes. The current study aimed to evaluate the knowledge about HCV infection amongst dental students and their attitudes towards patients infected with HCV. METHODS: A cross-sectional survey was conducted amongst 340 Brazilian dental students from two public universities using an instrument containing information regarding demographic characteristics, knowledge of HCV and attitudes towards patients with HCV infection. Descriptive statistics, Fisher's exact test, Student's t-tests, Mann-Whitney U-test and multiple logistic regression (MLR) were carried out (P < 0.05 was considered significant). RESULTS: Response rate was 90% (n = 306), and more than half (54%, n = 165) of participants had high knowledge level (above the mean); 97.7% (n = 299) demonstrated positive attitudes. MLR showed that high knowledge of dental students regarding HCV was substantially influenced by advancement in year of study (last year; P < 0.001) and type of university (federal; P = 0.049). Positive attitude towards HCV-infected patients was mainly influenced by age (P = 0.004) and male gender (P = 0.022). CONCLUSIONS: These results demonstrated a satisfactory knowledge about HCV infection amongst dental students, but some gaps were observed, suggesting the importance of continuous education about HCV in this population to prevent HCV infection as well as discrimination and prejudice towards patients with hepatitis C.

Anti-SPAG16 antibodies in primary progressive multiple sclerosis are associated with an elevated progression index.

BACKGROUND AND PURPOSE: Sperm-associated antigen 16 (SPAG16), a sperm protein which is upregulated in reactive astrocytes in multiple sclerosis (MS) lesions, has recently been identified as a novel autoantibody target in MS. The aim of this study was to investigate whether anti-SPAG16 antibody levels differ between MS subtypes (relapsing-remitting, RR; primary or secondary progressive, PP, SP) and whether antibody positivity is associated with clinical characteristics. METHODS: Plasma anti-SPAG16 antibody levels were determined by recombinant protein enzyme-linked immunosorbent assay (ELISA) in 374 MS patients (274 RRMS, 39 SPMS and 61 PPMS) and 106 healthy controls. RESULTS: Significantly elevated anti-SPAG16 antibodies were found in 22% of MS patients with 93% specificity. Anti-SPAG16 seropositivity was associated with an increased Expanded Disability Status Scale (EDSS) in overall MS. A higher proportion of PPMS patients showed anti-SPAG16 antibody reactivity (34%) compared to RRMS (19%) and SPMS (26%), and presented with higher anti-SPAG16 antibody levels. Seropositive PPMS patients had a significantly increased progression index compared to seronegative patients. CONCLUSIONS: Anti-SPAG16 antibodies are associated with an increased EDSS in overall MS, indicating that they are linked to a worse MS disease outcome. Moreover, the presence of anti-SPAG16 antibodies may be a biomarker for a more severe disease in PPMS patients, as indicated by an increased progression index.

Natural killer cell subsets in cerebrospinal fluid of patients with multiple sclerosis.

Changes in blood natural killer (NK) cells, important players of the immune innate system, have been described in multiple sclerosis (MS). We studied percentages and total cell counts of different effector and regulatory NK cells in cerebrospinal fluid (CSF) of MS patients and other neurological diseases to gain clearer knowledge of the role of these cells in neuroinflammation. NK cell subsets were assessed by flow cytometry in CSF of 85 consecutive MS patients (33 with active disease and 52 with stable MS), 16 with other inflammatory diseases of the central nervous system (IND) and 17 with non-inflammatory neurological diseases (NIND). MS patients showed a decrease in percentages of different CSF NK subpopulations compared to the NIND group. However, absolute cell counts showed a significant increase of all NK subsets in MS and IND patients, revealing that the decrease in percentages does not reflect a real reduction of these immune cells. Remarkably, MS patients showed a significant increase of regulatory/effector (CD56(bright) /CD56(dim) ) NK ratio compared to IND and NIND groups. In addition, MS activity associated with an expansion of NK T cells. These data show that NK cell subsets do not increase uniformly in all inflammatory neurological disease and suggest strongly that regulatory CD56(bright) and NK T cells may arise in CSF of MS patients as an attempt to counteract the CNS immune activation characteristic of the disease.

Cerebrospinal fluid immunological biomarkers associated with axonal damage in multiple sclerosis.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) neurofilament light protein (NFL) is a promising biomarker of axonal injury and neurodegeneration. Here CSF lymphocyte subpopulations and antibodies, potential players of neurodegeneration, are examined in relation to CSF NFL shedding in MS. METHODS: Cerebrospinal fluid NFL from 127 consecutive untreated MS patients was analysed. Samples from 37 age-matched patients with other central nervous system non-inflammatory neurological diseases (NIND) were also assessed. CD4+, CD8+, CD56+ and CD19+ cell subsets were studied by flow cytometry. Oligoclonal IgG and IgM bands (OCMB) against lipids were studied by isoelectric focusing and immunoblotting. These data were analysed in relation to clinical and magnetic resonance imaging features. RESULTS: A CSF NFL cut-off value of 900 ng/l (mean + 3 SD of NIND values) was calculated. MS patients with increased NFL values showed significantly higher Multiple Sclerosis Severity Score and magnetic resonance imaging lesion number. The presence of OCMB (P < 0.0001) and elevated T and B lymphocyte counts was associated with increased levels of CSF NFL. CONCLUSIONS: High CSF NFL levels are associated with elevated CSF lymphocyte cell counts and intrathecal synthesis of IgM against lipids. These findings support a role for OCMB in the axonal damage of MS offering a rationale for the association of these antibodies with disability and brain atrophy progression in MS.

Anti-myelin antibodies play an important role in the susceptibility to develop proteolipid protein-induced experimental autoimmune encephalomyelitis.

Multiple sclerosis (MS) is the most common demyelinating disease of the central nervous system. It is an autoimmune disorder in which activated T cells cross the blood-brain barrier (BBB) to initiate an inflammatory response that leads to demyelination and axonal damage. The key mechanisms responsible for disease initiation are still unknown. We addressed this issue in experimental autoimmune encephalomyelitis (EAE), the animal model of MS. It is widely known that EAE manifests only in certain strains when immunized with myelin proteins or peptides. We studied the differential immune responses induced in two mouse strains that are susceptible or resistant to EAE induction when they are immunized with the 139-151 peptide of proteolipid protein, an encephalitogenic peptide capable of inducing EAE in the susceptible strain. The adequate combination of major histocompatibility complex alleles and myelin peptides triggered in susceptible mice a T helper type 17 (Th17) response capable of inducing the production of high-affinity anti-myelin immunoglobulin (Ig)G antibodies. These were not detected in resistant mice, despite immunization with the encephalitogenic peptide in junction with complete Freund's adjuvant and pertussis toxin, which mediate BBB disruption. These data show the pivotal role of Th17 responses and of high-affinity anti-myelin antibodies in EAE induction and that mechanisms that prevent their appearance can contribute to resistance to EAE.

Identification of the major HHV-6 antigen recognized by cerebrospinal fluid IgG in multiple sclerosis.

BACKGROUND AND PURPOSE: Different data show an association between human herpesvirus 6 (HHV-6) and multiple sclerosis (MS). Intrathecal anti-HHV-6 immunoglobulin G (IgG) was detected in MS patients, but the antigen recognized by cerebrospinal fluid (CSF) IgG has not been characterized yet. Our objective was to identify the HHV-6 antigens recognized by IgG present in the CSF of patients with MS. METHODS: Cerebrospinal fluid IgG of 15 MS patients and eight patients with other neurological diseases was purified on protein G Sepharose columns. Purified IgG from every patient was linked to a CNBr-activated Sepharose 4B column. Fifty micrograms of viral extract was applied to each column. Bound proteins were eluted and analysed by SDS-PAGE and silver staining. The viral protein was characterized by mass spectrometry. RESULTS: A protein of 150 kD was eluted from CSF IgG columns of three of eight patients with primary progressive MS and one of seven with relapsing-remitting MS. After digestion and mass spectrometry analysis 10 peptides were found with 100% homology with the major capsid protein of the HHV-6A. DISCUSSION: These findings confirm the presence of anti-HHV-6 IgG in CSF of MS patients, particularly in progressive forms, and identify major capsid protein as the major antigen recognized by CSF IgG from MS patients.

Dried blood spot samples: optimization of commercial EIAs for hepatitis C antibody detection and stability under different storage conditions.

This study was undertaken to optimize and compare the efficiency of two commercial EIAs for anti-HCV detection (HCV Ab Radim, Pomezzia, Italy and ETI-AB-HCVK-4 DiaSorin, Vercelli, Italy), in dried blood spot (DBS) samples. The long-term stability of anti-HCV on DBS samples stored at three environmental conditions was also evaluated at: 2-8 °C, 20-25 °C, and -20 °C. Paired DBS and serum samples were obtained from individuals with or without anti-HCV. The type of elution buffer, sample and conjugate volume, sample incubation time and cut-off values were evaluated. For both EIAs, a larger sample volume was used, and the cut-off value determined by the manufacturer was employed for Radim EIA; however, ROC curve analysis was used for the DiaSorin EIA. The sensitivity and specificity of Radim EIA on DBS were 97.5% and 99.5%, respectively, and of DiaSorin EIA were 88.9% and 98.9%, respectively. Accurate results were obtained for a period of 117 days using DBS samples stored at all storage conditions, but storage at -20 °C resulted in the lowest variation among the absorbance values. Both EIAs demonstrated the same limit of detection (until dilution of 1:10(4) with estimated viral load of 3.1 × 10(-1) UI/ml), but the Radim EIA was associated with the best performance because a low coefficient of variation was observed in the repetition and reproducibility studies. In conclusion, commercial EIAs can be optimized for anti-HCV detection in DBS samples that are extremely stable at different conditions for more than 100 days.

An evaluation of different saliva collection methods for detection of antibodies against hepatitis C virus (anti-HCV).

BACKGROUND: Saliva samples can be used as an alternative fluid for against hepatitis C virus (anti-HCV) detection owing to the ease of collection and excellent acceptability. This study was conducted to optimize a commercial enzyme immunoassay (EIA) to detect anti-HCV in saliva samples. METHODS: Ninety-six individuals donated paired serum and saliva samples that were obtained, using a commercial device (Salivette) and spitting into a sterile container. Initially, elution buffer for the Salivette samples, sample volume, incubation time and temperature, and two different anti-HCV EIAs were evaluated. Using the optimized assay, three methods for cut-off calculation were also evaluated. RESULTS: A 20-fold increase in the sample volume for both collection methods was needed. Moreover, the Radim assay was the most appropriate assay for anti-HCV detection in saliva samples, and the quality parameters were increased when a ROC curve was used to determine the cut-off value. Using this optimized assay, the sensitivities, specificities, accuracies, positive and negative predictive values were above 90% for saliva obtained using both the Salivette and spitting methods. Using this assay, discordant false-negative results were obtained for only two Salivette samples and five spitting samples. The concordance kappa was 93% for the Salivette method and 86.1% for the spitting method, demonstrating excellent performance. CONCLUSIONS: Saliva samples obtained for both methods can be employed for anti-HCV detection among HCV-infected or HCV-suspected cases, but several modifications must be performed on commercial EIAs to obtain good results. Moreover, samples obtained with commercial devices are more appropriate for anti-HCV detection in saliva samples.

[Vaccination against SARS-CoV-2 in patients with multiple sclerosis]. / Vacunación frente al SARS-CoV-2 en pacientes con esclerosis múltiple.

INTRODUCTION: The recent availability of SARS-CoV-2 vaccines has raised concerns in certain patient groups, such as those with multiple sclerosis. However, there are currently few publications that provide information on this issue. We pooled the information available on the safety and efficacy of vaccination against SARS-CoV-2 in patients with multiple sclerosis, with and without disease-modifying therapy. DEVELOPMENT: The study consisted in a literature search focused on the types of SARS-CoV-2 vaccines, the current status of their approval, and the data available on the safety and efficacy of vaccines in patients with multiple sclerosis, including the new COVID-19 vaccines. Based on this search, the document has been designed taking into account current evidence and expert recommendations. There are no data on the safety and efficacy of SARS-CoV-2 vaccines in patients with multiple sclerosis. However, evidence does exist to suggest that messenger RNA (mRNA) vaccines against SARS-CoV-2 are as safe in these patients as in other individuals. Some therapies with immunosuppressants might reduce the effectiveness of these vaccines and require the scheduling of their administration, preferably before the start of treatment if possible. CONCLUSION: The data available make it possible to recommend mRNA vaccines against SARS-CoV-2 in patients with multiple sclerosis. In patients on fingolimod, cladribine, alemtuzumab, ocrelizumab and rituximab, vaccination prior to the initiation of medication administration would be recommendable whenever possible.

TITLE: Vacunación frente al SARS-CoV-2 en pacientes con esclerosis múltiple.Introducción. La reciente disponibilidad de vacunas contra el SARS-CoV-2 ha suscitado dudas en determinados colectivos de pacientes, como los que padecen esclerosis múltiple. Sin embargo, en la actualidad hay pocas publicaciones que ofrezcan información en este sentido. Se recopila la información disponible sobre la seguridad y la eficacia de la vacunación contra el SARS-CoV-2 en pacientes con esclerosis múltiple, con y sin tratamiento modificador de la enfermedad. Desarrollo. Búsqueda bibliográfica enfocada en los tipos de vacunas contra el SARS-CoV-2, la situación actual de su aprobación, y los datos disponibles sobre la eficacia y la seguridad de las vacunas en pacientes con esclerosis múltiple, incluidas las nuevas vacunas frente a la COVID-19. A partir de esta búsqueda, se ha diseñado el documento recogiendo la evidencia actual y las recomendaciones de expertos. No existen datos sobre la seguridad y la eficacia de las vacunas contra el SARS-CoV-2 en pacientes con esclerosis múltiple. Sin embargo, los datos disponibles permiten prever que las vacunas de tipo ARN mensajero (ARNm) frente al SARS-CoV-2 son tan seguras en ellos como en el resto de los individuos. Algunos de los tratamientos inmunosupresores podrían reducir la efectividad de las vacunas y requerir la planificación del momento de su administración, preferentemente antes del inicio del tratamiento en caso de ser posible. Conclusión. Los datos disponibles permiten recomendar las vacunas de tipo ARNm frente al SARS-CoV-2 en los pacientes con esclerosis múltiple. En los pacientes con fingolimod, cladribina, alemtuzumab, ocrelizumab y rituximab, sería recomendable la vacunación previa al inicio de la medicación cuando sea posible.

Response to interferon in multiple sclerosis is related to lipid-specific oligoclonal IgM bands.

The objective of this study was to investigate whether the presence of lipid-specific oligoclonal IgM bands (LS-OCMB) in cerebrospinal fluid (CSF) influences the response to treatment with beta-interferon in relapsing-remitting multiple sclerosis (RRMS) patients. We performed a collaborative prospective study including RRMS patients with brain MRI and LS-OCMB studies performed before starting interferon treatment. The primary endpoint was the risk of having a relapse after treatment initiation. Secondary endpoints included relapse rate, relapse-rate reduction, proportion of relapse-free patients and proportion of patients with sustained disability increase during follow-up. One-hundred and two patients were included. After a mean follow-up of 37.4 months, the risk of suffering a relapse was two-fold higher in patients with LS-OCMB (hazard ratio 2.0, 95% confidence interval 1.1-3.8). LS-OCMB+ patients showed lower reduction in relapse rate (51.8% versus 80.8%; p < 0.0001), higher relapse rate in the first year (0.8 versus 0.2; p = 0.001), lower proportion of relapse-free patients (25% versus 61.3%; p = 0.003), and higher proportion of patients with sustained 1.0 increase in the Expanded Disability Status Score (45% versus 12.9%; p = 0.0003). In conclusion, LS-OCMB can have an influence on the response to interferon treatment in RRMS patients. They could be used as a biological marker to predict high inflammatory activity after treatment.

Multiple sclerosis patients with anti-lipid oligoclonal IgM show early favourable response to immunomodulatory treatment.

BACKGROUND AND PURPOSE: Interferon beta and Glatiramer acetate are safe immunomodulatory treatments (IT) for multiple sclerosis (MS), but not always effective. New drugs are available, although they show more side-effects and unknown long-term safety profile. Anti-lipid oligoclonal IgM bands (OCMB) distinguish MS patients with early aggressive course. We prospectively studied if IT are effective in these patients or if they are candidates for more aggressive drugs as first therapeutic option. METHODS: Seventy-five clinically isolated syndrome patients were studied. OCMB and conversion to MS were assessed. Patients suffering at least two demyelinating events within 3 years were considered eligible to start IT. RESULTS: Eighteen patients showed OCMB (M+) and 57 lacked them (M-). All M+ patients and only 25 M- patients were treated. The other 32 M- patients suffered less MS attacks than those required to initiate treatment. IT similarly reduced relapse rate in both treated groups (P < 0.0001) and reduced Expanded Disability Status Scale (EDSS) progression in M+ patients, whose EDSS score had significantly increased before treatment. EDSS did not change in M- patients during follow-up, regardless if they were treated or not. CONCLUSIONS: Oligoclonal IgM bands identify MS patients who are candidates for early immunomodulatory treatment as IT improves their initial aggressive disease course.

Hepatitis A virus in environmental water samples from the Amazon Basin.

Hepatitis A virus (HAV) is a significant waterborne human pathogen. Of the global supply of potable water, Brazil retains 13%, of which 75% resides in the Amazon Basin. Although hepatitis A morbidity has declined progressively in Brazil as a whole, it remains high in the Amazon region. We used nested and real-time reverse-transcription polymerase chain reaction (RT-PCR) to detect and quantify the viral load in water samples from the Amazon Basin. Most samples tested positive (92%), with viral loads varying from 60 to 5500 copies /L, depending on sanitary conditions and the degree of flooding. Nested RT-PCR of the VP1-2A region detected HAV RNA in 23% of the samples. In low viral load samples, HAV was detected only with real-time RT-PCR, suggesting that this technique is useful for monitoring HAV contamination. The presence of HAV in water samples constitutes a serious public health problem.