Increased renal damage in hypocomplementemic patients with ANCA-associated vasculitis: retrospective cohort study.

INTRODUCTION: The complement system has an important role in the pathogenesis of vasculitis associated with antineutrophilic cytoplasmic antibody (AAV) mainly at the level of the kidneys because patients with complement deposits on the glomerular basal membrane present more aggressive disease compared with those with pauci-immune vasculitis. AIM: To analyze the association of hypocomplementemia with the clinical manifestations, laboratory data, renal histology, progress to renal insufficiency, and mortality of patients with AAV. METHODS: Retrospective cohort study (2000-2007) included 93 patients with AAV. Hypocomplementemia is defined as having C3 values lower than 80 mg/dL or C4 values below 15 mg/dL. Demographic, statistical, clinical, hematological, serological, and histopathological characteristics of all the patients with and without diagnosis of hypocomplementemia were compared. In order to evaluate variable independence, a logistic regression analysis was used. RESULTS: Ninety-three patients were studied of whom 63 (67.7%) had complement dosage at the moment of AAV diagnosis. Seven patients (11.1%) presented hypocomplementemia and a greater kidney involvement compared with normocomplementemic patients. Thirty renal biopsies were analyzed and 4 (13.3%) showed immunocomplex (IC) or complement deposits by an immunofluorescence test (IFT). Patients with "non-pauci-immune" AAV also presented terminal chronic renal disease (TCRD). CONCLUSION: There is an association between low complement and the degree of renal damage in patients with AAV. Patients with renal biopsies confirming IC and/or complement deposits showed more aggressive renal disease. Key Points • The complement system has an important role in the pathogenesis of vasculitis associated to antineutrophilic cytoplasmic antibody. • The studies in murine models confirming the complement activation by alternative pathway and particularly the receptor C5a (C5aR) is necessary for the development of glomerulonefritis. • Complement deposit observed in the renal biopsies of patients diagnosed with AAV was correlated to greater kidney damage, greater proteinuria and major disease activity compared to patients diagnosed with typical pauci-immune vasculitis. • The presence of hypocomplementemia at the onset of the disease was also associated with a greater organ involvement, poor prognosis and greater mortality.

Características de los tratamientos biológicos en enfermedades reumáticas en Argentina: quinto informe del registro BIOBADASAR / Features of rheumatic diseases biological treatments in Argentina: BIOBADASAR fifth report

Introducción: El proyecto BIOBADASAR (Registro argentino deeventos adversos con tratamientos biológicos en reumatología)comenzó en agosto de 2010, para recabar información a largo plazosobre los eventos adversos en tratamientos biológicos en pacientescon enfermedades reumáticas en la práctica clínica cotidiana enArgentina.Pacientes y método: Se registraron datos de cada paciente,tratamientos y acontecimientos adversos relevantes o importantes.Los pacientes debían tener enfermedad diagnosticada y tratadacon un agente biológico. Cada caso se comparó con un control:un paciente con tratamiento no biológico con característicasdemográficas similares. Se analizaron los datos con análisis de lavarianza, con test de t de Student, Mann Whitney, test chi2, o testexacto de Fisher. El análisis de supervivencia de los tratamientoshasta su discontinuación o interrupción se realizó con el método deKaplan-Meier y test log-rank...

Background: BIOBADASAR (Argentine Registry of Adverse Eventsin Biological Treatments in Rheumatology) was started in August2010 to obtain long-term information of patients with rheumatic diseases,treatments and adverse events in everyday clinical practice.Patients and methods: Data on patients’ demographics,treatments and adverse events were collected. Patients had a diagnosisof a rheumatic disease and were treated with biological agent.To compare information, a control group was included, consisting ofpatients treated with similar demographic characteristics but treatedwith a non-biological agent. Data were analysed with Anova,Student´s t, Mann Whitney, chi2, Fisher´s exact tests, as appropriate.Survival analysis of treatments was performed with Kaplan-Meiercurves and log-rank test...

Tercer reporte de eventos adversos con tratamientos biológicos en Argentina. Informe de registro biobadasar / Thrid report of adverse events with biologics in Argentina. Report from biobadasar registry

Introducción: BIOBADASAR (Registro Argentino de Eventos Adversos con Tratamientos Biológicos en Reumatología) comenzó en agosto de 2010. La importancia de este registro es mostrar datos locales que, probablemente, puedan diferir de otros registros. El objetivo es comunicar los resultados del tercer reporte de BIOBADASAR. Métodos: Todos los pacientes con enfermedades reumáticas que requirieron tratamiento con agentes biológicos y pacientes controles sin estos tratamientos fueron incluidos en la base de datos provenientes de 32 centros participando a lo largo de la Argentina. Tres áreas de datos son analizados: características de los pacientes, tratamientos y eventos adversos...

Introduction: BIOBADASAR (Argentine Registry of Adverse Events with Biological Treatments in Rheumatology) began in August 2010. The importance of this registry is to show local data that may probably differ from other registries. The objective is to communicate the results of the third BIOBADASAR report. Methods: All patients with rheumatic diseases who required treatment with biological agents and control patients without these treatments were included in the database from 32 participating centers throughout Argentina. Three areas of data are analyzed: patient characteristics, treatments and adverse events...

RET proto-oncogene mutations are restricted to codon 618 in Cypriot families with multiple endocrine neoplasia 2.

BACKGROUND: RET germline mutations predispose to the development of inherited cancer syndrome multiple endocrine neoplasia type 2 (MEN2). Several variants of the RET proto-oncogene including G691S and S904S have been suggested to act as genetic modifiers at the age of onset ofMEN2. AIM: The aim of this study is to characterize clinically and molecularly 7 Cypriot patients with familial medullary thyroid carcinoma (FMTC) and 1 with MEN2A and also to determine the allelic frequencies of the RET variants G691S and S904S. SUBJECTS AND METHODS: Seven probands from FMTC families and 1 from MEN2A were screened for the presence of RET mutations and the G691S and S904S variants. Additionally, 226 healthy Cypriots, who served as controls were analysed in an attempt to compare the frequencies of G691S and S904S RET variants to those observed in the 8 patients. RESULTS: The clinical diagnosis of the probands was based on clinical presentation and supported with biochemical findings. The germline C618R mutation of exon 10 was identified in all 8 probands and in 15 relatives from 7 different families. No significant difference in the G691S/S904S variants allele frequencies between patients (4/16 or 25%) and controls (124/452 or 27.4%) was found. CONCLUSIONS: Mutational screening of the RET gene identified a common mutation (C618R) in all 8 (7 FMTC and 1 MEN2A) unrelated Cypriot patients which may be explained by a founder effect. Additionally, no association of the G691S/S904S variants was linked with the disease.

Low rate of occult hepatitis B virus infection among anti-HBc positive blood donors living in a low prevalence region in Brazil.

OBJECTIVE: The aim of this study was to determine the rate of occult hepatitis B virus (HBV) infection among blood donors living in a geographic region of low (5.6%) anti-HBc prevalence. SUBJECTS AND METHODS: Sera from 150 candidate blood donors whose blood was rejected due to total anti-HBc reactivity (despite absence of HBsAg) were tested for anti-HBs and IgM anti-HBc antibodies, as well as for HBeAg/anti-HBe. Serum HBV DNA was sought by using a PCR assay able to amplify part of the surface gene. Viral load was measured in the PCR positive samples. RESULTS: The pattern 'anti-HBc alone' (without HBsAg and anti-HBs antibodies) was found in 64 (42.7%) subjects. IgM anti-HBc and anti-HBe antibodies were detected in 2 (1.3%) and 80 (53.3%) samples, respectively. No sample was HBeAg-reactive. HBV DNA was repeatedly found in five (3.3%) samples, three of which were anti-HBs positive and two anti-HBs negative. All five HBV DNA positive samples showed a low viral load (<1000copies/ml). CONCLUSIONS: The data indicated a low rate of occult infection among anti-HBc positive, HBsAg negative blood donors living in a region of low prevalence of infection. Viral load was very low in all HBV infected subjects.

Novel PKD1 deletions and missense variants in a cohort of Hellenic polycystic kidney disease families.

The autosomal dominant form of polycystic kidney disease is a very frequent genetically heterogeneous inherited condition affecting approximately 1 : 1000 individuals of the Caucasian population. The main symptom is the formation of fluid-filled cysts in the kidneys, which grow progressively in size and number with age, and leading to end-stage renal failure in approximately 50% of patients by age 60. About 85% of cases are caused by mutations in the PKD1 gene on chromosome 16p13.3, which encodes for polycystin-1, a membranous glycoprotein with 4302 amino acids and multiple domains. Mutation detection is still a challenge owing to various sequence characteristics that prevent easy PCR amplification and sequencing. Here we attempted a systematic screening of part of the duplicated region of the gene in a large cohort of 53 Hellenic families with the use of single-strand conformation polymorphism analysis of exons 16-34. Our analysis revealed eight most probably disease causing mutations, five deletions and three single amino acid substitutions, in the REJ domain of the protein. In one family, a 3-bp and an 8-bp deletion in exons 20 and 21 respectively, were co-inherited on the same PKD1 chromosome, causing disease in the mother and three sons. Interestingly we did not find any termination codon defects, so common in the unique part of the PKD1 gene. In the same cohort we identified 11 polymorphic sequence variants, four of which resulted in amino acid variations. This supports the notion that the PKD1 gene may be prone to mutagenesis, justifying the relatively high prevalence of polycystic kidney disease.

Behavioral estimates of absolute visual threshold in mice.

Behavioral measurements on the water maze show night blindness in albino mice but cortical recordings show no difference between pigmented and congenic albino mice. Consequently we have measured the absolute threshold in albino and pigmented mice using an operant method. The estimated threshold value is -5.3 log cd/m2 for albino mice and -5.5 log cd/m2 for the pigmented mice. We conclude that threshold values depend on the behavioral paradigm used. Operant behavioral thresholds show that albino and pigmented mice detect levels of light similar to their VEP thresholds. Cognitive differences might influence the estimation of absolute behavioral threshold in albino animals.