[Diagnosis of neurocysticercosis in patients with epilepsy living in the south-western Dominican Republic]

INTRODUCTION

Neurocysticercosis (NCC), a possible cause of epilepsy with limited epidemiological data in the Dominican Republic, is endemic in four provinces in the country's south-western region. This study aimed to determine the association between NCC and epilepsy among people living in these endemic regions, and to obtain preliminary data on the prevalence of NCC in these provinces.

PATIENTS AND METHODS

A case-control design was used, consisting of 111 patients with epilepsy with unknown causes, and 60 controls without epilepsy or NCC. The diagnosis of NCC was based on computed tomography and magnetic resonance imaging of the skull, as well as Western immunoblotting for serum antibodies using Taenia solium, following the criteria of Del Brutto et al. RESULTS. NCC was found in 27% of the epileptic patients (n = 30/111) and in 5% of the controls (n = 3/60); the probability of the epileptic patients having NCC was seven times higher than the controls (odds ratio = 7.04, 95% confidence interval: 2.04-24.18; p < 0.001). The participants' sociodemographic characteristics, including their age, sex, level of education, occupation, and province of residence presented no statistical significance in terms of their association with NCC.

CONCLUSIONS

This study suggests that NCC is strongly associated with epilepsy in the south-western region of the Dominican Republic, and highlights the need for public health measures to improve the prevention, diagnosis and treatment of both diseases.

Effects of the lockdown due to the COVID-19 pandemic on alcohol consumption in patients under treatment in an alcohol relapse prevention programme

During the COVID-19 pandemic, several exceptional measures were put in place in order to avoid virus propagation, such as lockdown and the discontinuation of usual health care assistance services. It was considered that these changes might be associated with an increase in alcohol consumption and a higher risk of relapse for patients under treatment. The aim of this study was to assess changes in alcohol consumption during the lockdown period (between March and May, 2020) in patients following treatment under the Alcohol Use Disorders Programme at the "Hospital 12 de Octubre" in Madrid. A total of 311 patients were assessed through interviews carried out by telephone in accordance with usual clinical practice during that period. 76% of the total number of patients did not experience changes in their alcohol consumption, 9.2% stopped drinking and some experienced severe withdrawal syndrome, while 7.5% relapsed. The risk factors found for worsening the prognosis of the patients were: being female, drinking alcohol alone or at home, binge drinking, concomitant substance misuse and failure to attend therapy groups or self-help groups online during the lockdown. 31.6% of the sample described psychopathological symptoms due to the lockdown, especially those who already had psychiatric comorbidities. For this reason, we can conclude that during the lockdown as a result of the pandemic, most of our alcohol dependent patients did not modify their drinking patterns, but specific factors enabled us to identify a more vulnerable subgroup.

Yersinia ruckeri infection activates local skin and gill B cell responses in rainbow trout

Teleost fish lack organized structures in mucosal tissues such as those of mammals, but instead contain dispersed B and T cells with the capacity to respond to external stimuli. Nonetheless, there is still a great lack of knowledge regarding how B cells differentiate to plasmablasts/plasma cells in these mucosal surfaces. To contribute to a further understanding of the mechanisms through which fish mucosal B cells are activated, in the current study, we have studied the B cell responses in the skin and gills of rainbow trout (Oncorhynchus mykiss) exposed to Yersinia ruckeri. We have first analyzed the transcription levels of genes related to B cell function in both mucosal surfaces, and in spleen and kidney for comparative purposes. In a second experiment, we have evaluated how the infection affects the presence and size of B cells in both skin and gills, as well as the presence of plasmablasts secreting total or specific IgMs. The results obtained in both experiments support the local differentiation of B cells to plasmablasts/plasma cells in the skin and gills of rainbow trout in response to Y. ruckeri. Interestingly, these plasmablasts/plasma cells were shown to secrete specific IgMs as soon as 5 days after the exposure. These findings contribute to a further understanding of how B cells in the periphery respond to immune stimulation in teleost fish.

Influence of Humoral Response Against GnRH, Generated by Immunization with a Therapeutic Vaccine Candidate on the Evolution of Patients with Castration-Sensitive Prostate Adenocarcinoma

BACKGROUND AND AIMS

A gonadotropin-releasing hormone (GnRH)-based therapeutic vaccine candidate against hormone-sensitive prostate cancer has demonstrated its safety and signs of efficacy in phase I/II trials. In this study, we characterized the isotype/subclass profiles of the anti-GnRH humoral response generated by the vaccination and analyzed its association with patients' clinical outcomes.

METHODS

The immunoglobulin isotypes and IgG subclasses of the antibody responses of 34 patients included in a randomized, open, prospective phase I/II clinical trial were characterized. Every patient included in the study had a diagnosis of locally advanced prostate adenocarcinoma at stages 3 and 4 and received immunization with the vaccine candidate. Additionally, serum testosterone and prostate specific antigen (PSA) concentrations, serving as indicators of tumor response, were determined. The type of anti-GnRH antibody response was correlated to the time elapsed until the first biochemical recurrence in patients and the outcome of the disease.

RESULTS

All patients developed strong and prolonged anti-GnRH antibody responses, resulting in a short- to mid-term decrease in serum testosterone and PSA levels. Following immunizations, anti-GnRH antibodies of the IgM/IgG and IgG1/IgG3 subclasses were observed. Following radiotherapy, the humoral response switched to IgG (IgG1/IgG4). Patients who experienced a short-term biochemical relapse were characterized by significantly higher levels of anti-GnRH IgG titers, particularly IgG1 and IgG4 subclasses. These characteristics, along with a high response of specific IgM antibodies at the end of immunizations and the development of anti-GnRH IgA antibody responses following radiotherapy, were observed in patients whose disease progressed, compared to those with controlled disease.

CONCLUSION

The nature of the humoral response against anti-GnRH, induced by vaccination may play a key role in activating additional immunological mechanisms. Collectively, these mechanisms could contribute significantly to the regulation of tumor growth.

OP0299-HPR ANALYSIS OF THE ACCEPTANCE AND USEFULNESS OF A NON-PRESENTIAL CONSULTATION, IN PATIENTS WITH CHRONIC INFLAMMATORY JOINT DISEASES USING A DIGITAL PLATFORM

Background

The Covid-19 pandemic has meant a modification of the patterns of the doctor-patient relationship, favoring online visits and reducing face-to-face visits. Likewise, the implementation of Patient-Reported Outcomes (PROs) that do not require the intervention of the doctor in our clinical practice and that given their close relationship with the clinical activity of chronic inflammatory joint diseases (CIJD) has favored an empowerment of patients and can allow the development of the online visit.

Objectives

Know the use and acceptance of patients with CIJD: rheumatoid arthritis (RA), psoriatic arthritis (PsA) and spondyloarthropathies (SpA) of a non-face-to-face online visit, through a digital environment.

Methods

Patients were included in a platform called Rheumanet for access by username and passwords (https://www.laconsultacercadeti.com/). At the time of inclusion, demographic variables were collected: date of birth, sex, level of education (primary education, secondary education, vocational training, further education and higher education), distance from the hospital to the patient’s home, and clinical variables such as diagnosis: RA, PsA or SpA, as well as the duration of the disease. Prior to the appointment, patients were encouraged to complete a PRO survey to assess their clinical situation: Routine Assessment of Patient Index Data 3 (RAPID3) for RA, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for SpA and RAPID3 and / or BASDAI for the PsA. Both the RAPID3 and BASDAI were scored for the patient’s knowledge and assigned to a color scale based on disease activity in green (remission or low activity), orange (moderate activity) or red (severe activity). Likewise, they were ordered to express through a free text what they would tell us as if they were in a face-to-face consultation. Complementary tests (analytical, radiological studies and others) are obtained simultaneously from the medical records and a joint assessment of the visit is carried out.

Results

Between September 1, 2020 and January 31, 2022, a total of 248 patients (113 RA, 53 SpA and 82 PsA) were included in the platform. 172 (69.3%) patients used the digital platform and made at least one non-face-to-face visit during follow-up. The number of online visits made by each patient ranged from 1 to a maximum of 13 visits. 80 patients (70.7%) suffered from RA, 40 (75.4%) from SpA and 52 (63.4%) from PsA. The number of patients who made non-face-to-face visits was 38 (72.3%) for a disease duration of <5 years and 137 (64.5%) for >5 years. When the ages of the patients were analyzed, the number of patients who made visits was 75 (73.5%) between 18 and 30 years old, 50 (67.7%) between 30 and 50 and 47 (66.4 %) from 50 years. According to the degree of activity of the disease, 75 patients were in remission or low activity at some point during the visits, 63 patients with moderate activity and 34 with severe activity. The distribution according to level of education was: 11 (6.3%) primary education, 21 (12.2%) secondary education, 37 (21.5%) vocational training, 63 (36.6%) further education and 40 (23.2%)higher education. The number of online visits was higher in patients who lived at a distance of 50 km or more from the hospital, reaching 100% of the visits in this subgroup of patients.

Conclusion

The online visit through a digital platform through PROs is well accepted by our population with CIJD, especially in the young population, with a higher cultural level and whose home is far from the hospital. The online visit was made by patients regardless of the severity of their disease activity. Speed and ease of use using PROs already known to the patient and clinician is an important consideration for rheumatologists working in healthcare systems where patient contact time is limited. It would be interesting to obtain this information in non-pandemic situations such as COVID-19, which would make it possible to assess actual acceptance and its use in this type of patient in circumstances in which fear of contagion is not a variable to consider.

Disclosure of Interests

None declared

Origin makes a difference: Alternative responses of an AM-dependent plant to mycorrhizal inoculum from invaded and native soils under abiotic stress

The presence of invasive alien plants (IAPs) alters the composition of soil arbuscular mycorrhizal (AM) fungal communities. Although fundamental for plant development, plant responses to AM from invaded soils have not been widely explored, especially under environmental stress. We compared plant growth, P accumulation, root colonization and the photosynthetic responses of the native AM-dependent Plantago lanceolata growing in contact with AM fungi from communities invaded by Acacia dealbata Link (AMinv) or non-invaded communities (AMnat) exposed to water and light restriction (shade). Under optimal growing conditions, plants in contact with AMnat produced higher leaf biomass and accumulated more P. However, plant responses to different AM inocula varied as the level of stress increased. Inoculation with AMinv promoted plant growth and root length under light restriction. When plants grew in contact with AMnat under drought, leaf P increased under severe water restriction, and leaf and root P increased under intermediate water irrigation. Growing in contact with the AMnat inoculum promoted root P content in both full light and light restriction. Colonization rates of P. lanceolata roots were comparable between treatments, and plants maintained photosynthetic activity within similar ranges, regardless of the level of stress applied. Our results suggest that origin of the inoculum (native soils versus invaded soils) did not affect the ability of AM species therein to establish effective mutualistic associations with P. lanceolata roots but did influence plant responses depending on the type and level of the abiotic stress.

HLA genetic polymorphisms and prognosis of patients with COVID-19

Objective

Different genetic polymorphisms of human leukocyte antigen (HLA) have been associated with the risk and prognosis of autoimmune and infectious diseases. The objectives of this study were to determine whether there is an association between HLA genetic polymorphisms and the susceptibility to and mortality of coronavirus disease 2019 (COVID-19) patients.

Design

Observational and prospective study.

Setting

Eight Intensive Care Units (ICU) from 6 hospitals of Canary Islands (Spain).

Patients

COVID-19 patients admitted in ICU and healthy subjects.

Interventions

Determination of HLA genetic polymorphisms.

Main variable of interest

Mortality at 30 days.

Results

A total of 3886 healthy controls and 72 COVID-19 patients (10 non-survivors and 62 survivor patients at 30 days) were included. We found a trend to a higher rate of the alleles HLA-A*32 (p = 0.004) in healthy controls than in COVID-19 patients, and of the alleles HLA-B*39 (p = 0.02) and HLA-C*16 (p = 0.02) in COVID-19 patients than in healthy controls; however, all these p-values were not significant after correction for multiple comparisons. Logistic regression analysis showed that the presence of certain alleles was associated with higher mortality, such as the allele HLA-A*11 after controlling for SOFA (OR = 7.693; 95% CI = 1.063–55.650; p = 0.04) or APACHE-II (OR = 11.858; 95% CI = 1.524–92.273; p = 0.02), the allele HLA-C*01 after controlling for SOFA (OR = 11.182; 95% CI = 1.053–118.700; p = 0.04) or APACHE-II (OR = 17.604; 95% CI = 1.629–190.211; p = 0.02), and the allele HLA-DQB1*04 after controlling for SOFA (OR = 9.963; 95% CI = 1.235–80.358; p = 0.03).

Conclusions

The new finding from our preliminary study of small sample size was that HLA genetic polymorphisms could be associated with COVID-19 mortality; however, studies with a larger sample size before definitive conclusions can be drawn.

Association between red blood cell distribution width and mortality of COVID-19 patients

PURPOSE

We have previously reported an association between high red blood cell distribution width (RDW) and mortality in septic and brain infarction patients. However, no association between RDW and mortality in coronavirus disease 2019 (COVID-19) patients has been reported so far; thus, the objective of this study was to determine if that association exists.

METHODS

Prospective and observational study carried out in 8 Intensive Care Units from 6 hospitals of Canary Islands (Spain) including COVID-19 patients. We recorded RDW at ICU admission and 30-day survival.

RESULTS

We found that patients who did not survive (n=25) compared to surviving patients (n=118) were older (p=0.004), showed higher RDW (p=0.001), urea (p<0.001), APACHE-II (p<0.001) and SOFA (p<0.001), and lower platelet count (p=0.007) and pH (p=0.008). Multiple binomial logistic regression analysis showed that RDW was associated with 30-day mortality after controlling for: SOFA and age (OR=1.659; 95% CI=1.130-2.434; p=0.01); APACHE-II and platelet count (OR=2.062; 95% CI=1.359-3.129; p=0.001); and pH and urea (OR=1.797; 95% CI=1.250-2.582; p=0.002). The area under the curve (AUC) of RDW for mortality prediction was of 71% (95% CI=63-78%; p<0.001). We did not find significant differences in the predictive capacity between RDW and SOFA (p=0.66) or between RDW and APACHE-II (p=0.12).

CONCLUSIONS

Our study provides new information regarding the ability to predict mortality in patients with COVID-19. There is an association between high RDW and mortality. RDW has a good performance to predict 30-day mortality, similar to other severity scores (such as APACHE II and SOFA) but easier and faster to obtain.

AB0643 DRUG SURVIVAL OF SECUKINUMAB IN A SPONDYLOARTHRITIS COHORT. A 24 MONTHS MULTICENTRIC STUDY

Background:

Secukinumab inhibits the interaction between Interleukin 17A (IL-17A) and its receptor. Clinical trials have demonstrated good data in efficacy and safety in patients with spondyloarthritis (SpA) as first biological choice or inadecuate response to other biological in SpA. However there is few evidence in real clinical practice.

Objectives:

Evaluate the drug survival in a real clínical practice, as an indirect way to show the efficacy and security of Secukinumab at 24 months

Methods:

A multicentric observational, longitudinal, retrospective study of 24 months conducted in five Madrid hospitals (Spain). Patients older than 18 years treated with Secukinumab which fullfilled ASAS criteria for SpA and/or modified New York criteria for ankylosing spondylitis (AS) and/or CASPAR criteria for psoriatic arthritis (PsA) were included. For evaluation of the drug survival, dates from starting until closing date or definite withdrawal of the treatment were determined. Kaplan-Meier function was used to estimate the drug survival and Wilcoxon test for the comparison of the survival rate between the different diagnoses, because of the survival curves did not reach the median

Results:

A total of 71 patients were included. The mean age was 50.26 ys (SD 11.01), 57.75% women. 35 patients fullfilled classification criteria for PsA ant 36 fullfilled classification criteria for axSpA. 22 patients were naïve for biologic therapies and 49 patients had an inadecuate response to TNFi. 13 patients discontinued Secukinumab before the closing date, the main reason for the interruption was secondary failure (n= 6), and primary failure (n=2). Secukinumab survival rate was 81.95% up to 24 months in this cohort. The median of survival was 2.36 years (IC: 1.79-2.84). There were no significant differences about the drug survival related to diagnosis (p=0.976). The safety data were similar to those described in clinical trials.

Conclusion:

Secukinumab is an effective and safe treatment for the management of espondiloarthritis regardless of the subtypes, with a high survival rate. In this study naive patients show similar data obtained in clinical trials. In this cohort of patients, those who initiated secukinumab after failure to TNFi, showed a greater secukinumab survival than the data provided in clinical trials

Disclosure of Interests:

None declared

THU0168 GESTATIONAL DESIRE AND CERTOLIZUMAB PEGOL IN PATIENTS WITH CHRONIC INFLAMMATORY RHEUMATIC DISEASE. PRELIMINARY RESULTS OF THE GESTAMAD COHORT

Background:

The use of biological therapies during pregnancy has been contraindicated since the beginning of the use of these drugs. In recent years several studies have demonstrated the minimal-to-no transfer of certolizumab pegol (CZP) to the placenta and breast milk, which has allowed its approval for use in pregnancy and breastfeeding if clinically necessary. However, there are no studies evaluating the use of CZP during this period in real life or the characteristics of this subgroup of patients.

Objectives:

To describe the profile of women of childbearing age diagnosed with chronic inflammatory rheumatic disease (CIRD): Rheumatoid Arthritis (RA), Psoriatic Arthritis (PsA) and axial Spondyloarthritis (axSpA), who initiate CZP by gestational desire using the GESTAMAD registry (multicenter study of women with chronic inflammatory rheumatic disease of childbearing age who are initiated on CPZ by gestational desire from the Madrid community).

Methods:

Prospective multicenter study that aims to know the characteristics of women of childbearing age diagnosed with CIRD and gestational desire to which CZP is initiated for this reason. The comorbidities of the patients such as hypertension, diabetes and cardiovascular disease were collected. Disease activity was measured by DAS28 using CRP in RA and PsA and BASDAI in axSpA. The present study presents preliminary data from the initial cohort and will be followed prospectively for 24 months to assess the efficacy and safety of the drug during pre-conception, pregnancy and lactation.

Results:

A total of 45 patients have been recruited in 6 Madrid hospitals from June to December 2019. Patients had a mean age of 35.9, (36.6 in RA, 35.2 in PA and 35.1 in SPA). Fifty-one percent had RA, 20.0 percent had PA and 28.8 percent had SPA. The mean disease duration for RA, PA and SPA was 9.5, 7.3 and 6.9 years, respectively. 48.9% of women were nulliparous. The abortion rate of patients diagnosed with spondyloarthropathy was upper of 25%. 33.3% of the patients had been treated with previous biologicals, with gestational desire/pregnancy being the reason for the change.

75.5% of the patients had been treated with synthetic disease modifying antirheumatic drugs (DMARD) previously. With regard to disease activity, the mean DAS 28 at the start of treatment was 4.5 in RA and 3.8 in PA and BASDAI 7.0 in axSPA.

In RA the highest values of CRP and ESR were found prior to initiation with CZP, but this difference was not statistically significant (p=0.644 and 0.605, respectively). 22.2% of patients had previous comorbidities.

Conclusion:

The mean age of patients with gestational desire in CIRD is high. Women diagnosed with PsA and axSpA have a high rate of previous abortions, upper than 25%. The duration of the disease is equally long at the time of manifesting gestational desire. The use of treatments such as CZP, compatible with pregnancy and lactation would allow a better control of inflammatory joint disease in this period of life, encouraging patients not to postpone their gestational desire.

Disclosure of Interests:

None declared

AB0639 TREATMENT EFFICACY WITH SECUKINUMAB IN A COHORT OF SPONDYLOARTHRITIS PATIENTS

Background:

Spondyloarthropathies are a heterogeneous group of similar diseases, with interrelated clinical manifestations, such as Psoriasis Arthritis (APs) and Ankylosing Spondylitis (EA). There are different treatments for this group of pathologies.

Objectives:

It is very important to differentiate between those that present predominantly axial (spine and/or sacroiliac) or peripheral involvement, since the response to treatment is very different.

In some clinical trials, secukinumab significantly improved versus placebo, the symptoms and signs, physical function and quality of life, however, at present, we do not have enough data from secukinumab in real clinical practice.

This is the real reason of this study: the use of secukinumab in clinical practice.

Methods:

Multicentric longitudinal observational study of 5 Hospitals in Madrid.

Patients are over 18 years old and meet the following inclusion criteria: New York criteria for AS, ASAS for EA, CASPAR for APs, and all of them are with secukinumab or have received it.

We will evaluate the effectiveness rate as well as its confidence interval at 95%. In addition, the effectiveness of secukinumab will be compared in the different pathologies by using χ2.

Results:

72 patients were collected, 41 of them were women (57,75%).

12 patients (16,90%) had not received FAME before secukinumab and 22 patients (33,99%) were naive to biological treatment.

In 4 patients, the reason for starting secukinumab was the patient’s comorbidities, in 2 the adverse effects of previous treatment and in the rest, was the lack of efficacy of the previous treatment.

The patients were divided into 4 categories according to the level of DAS-28 or BASDAI, at the beginning of the treatment and the last recorded value, in: Absence of activity, mild, moderate and severe activity. Of the patients with data, they managed to improve the DAS-28 score (change category) by 30,95%, while only 4,76% worsened their score. With respect to BASDAI, of the total number of patients, only 3,03% worsened, while his score improved 27,27%.

According to baseline diagnosis, a greater improvement of the disease activity in peripheral APs(66,67%) and mixed APs(61,54%) is achieved.

Conclusion:

In real clinical practice, treatment with secukinumab was effective in patients with spondyloarthritis, achieving improvement in previous activity rates. In this study, the most significant improvement was obtained in peripheral and mixed APs.

Disclosure of Interests:

None declared

Safety and Therapeutic Profile of a GnRH-Based Vaccine Candidate Directed to Prostate Cancer. A 10-Year Follow-Up of Patients Vaccinated With Heberprovac

Heberprovac is a GnRH based vaccine candidate containing 2.4 mg of the GnRHm1-TT peptide as the main active principle; 245 μg of the very small size proteoliposomes adjuvant (VSSP); and 350 μL of Montanide ISA 51 VG oil adjuvant. The aim of this study was to assess the safety and tolerance of the Heberprovac in advanced prostate cancer patients as well as its capacity to induce anti-GnRH antibodies, the subsequent effects on serum levels of testosterone and PSA and the patient overall survival. The study included eight patients with histologically-proven advanced prostate cancer with indication for hormonal therapy, who received seven intramuscular immunizations with Heberprovac within 18 weeks. Anti-GnRH antibody titers, testosterone and PSA levels, as well as clinical parameters were recorded and evaluated. The vaccine was well tolerated. Significant reductions in serum levels of testosterone and PSA were seen after four immunizations. Castrate levels of testosterone were observed in all patients at the end of the immunization schedule, which remained at the lowest level for at least 20 months. In a 10-year follow-up three out of six patients who completed the entire trial survived. In contrast only one out eight patients survived in the same period in a matched randomly selected group receiving standard anti-hormonal treatment. Heberprovac vaccination showed a good security profile, as well as immunological, biochemical and, most importantly, clinical benefit. The vaccinated group displayed survival advantage compared with the reference group that received standard treatment. These results warrant further clinical trials with Heberprovac involving a larger cohort.

Cost-Effectiveness of rFVIIa versus pd-aPCC in the Management of Mild to Moderate Bleeds in Pediatric Patients with Hemophilia A with Inhibitors in Mexico

OBJECTIVE

To compare the costs and clinical consequences of treating mild-to-moderate joint bleeds with recombinant activated factor VII (rFVIIa) versus plasma-derived activated prothrombin complex concentrate (pd-aPCC) in pediatric patients with hemophilia A with inhibitors in Mexico.

METHODS

A cost-effectiveness model was developed using TreeAge Pro v14.2.2 software (licensed in the USA) and adapted from a previously published model, with adjustments to reflect local clinical practice. Expert opinion was sought regarding patients' clinical management and resource utilization in Mexico to ensure that the current model was appropriate and relevant. The model compared rFVIIa and pd-aPCC for the treatment of mild-to-moderate joint bleeds in children <14 years old (assumed average weight: 30 kg). The analysis outcome was incremental cost per resolved mild-to-moderate joint bleed. One-way sensitivity analysis and probabilistic sensitivity analysis were used to assess specific assumptions and to address any uncertainty in the model.

RESULTS

The cost of treating mild-to-moderate joint bleeds was lower for rFVIIa versus pd-aPCC after 7 days (MX$105,581 vs. MX$132,024), assuming complete bleed resolution. After 48 hours, rFVIIa was associated with an 8% improvement in bleed resolution versus pd-aPCC, resulting in cost savings of MX$16,754. Probabilistic sensitivity analysis indicated that rFVIIa treatment was more cost-effective than pd-aPCC in 67% (at 7 days) and 72% (at 48 hours) of Monte Carlo simulations.

CONCLUSION

Accounting for model uncertainty, rFVIIa provided cost savings over pd-aPCC for the Mexican public health care payer in the management of mild-to-moderate joint bleeds in pediatric hemophilia A with inhibitors.

Concordance of the ions and GAP anion obtained by gasometry vs standard laboratory in critical care

OBJECTIVE

To evaluate the differences observed in ion and GAP anion determinations obtained by point-of-care (POC) blood gas versus laboratory biochemical testing, and to analyze the possible errors according to the limits of normality.

MATERIAL AND METHODS

A descriptive, cross-sectional retrospective study was made to assess concordance between two diagnostic tests in patients admitted to the Critical Care Unit of Ourense University Hospital Complex (Spain), between July and November 2015, involving at least one coinciding biochemical test and POC determination. Patients under 18years of age were excluded.

RESULTS

A total of 1,073 samples were analyzed. Lin's concordance correlation coefficients for sodium, potassium and chlorine were 0.87, 0.84 and 0.72, respectively. Kappa concordance of the normality limits for sodium, potassium and chlorine was 0.63, 0.74 and 0.32. The results indicated poor correlation of the anion GAP and null concordance between POC and biochemical testing, including the value corrected for albumin.

CONCLUSIONS

Poor concordance was observed between the ion values as determined by biochemistry and blood gases; the two methods are therefore not interchangeable. Kappa agreement with normality limits was good for sodium and potassium, and weak for chlorine. Possible validity was noted in orienting the classification within the ion limits, with the exception of chlorine. No agreement was recorded in relation to the anion GAP, even that corrected for albumin.

Environmental Exposure of Children to Toxic Trace Elements (Hg, Cr, As) in an Urban Area of Yucatan, Mexico: Water, Blood, and Urine Levels

Merida is the largest urban center in the Mexican State of Yucatan. Here domestic sewage is deposited in poorly built septic tanks and is not adequately treated. Because of contamination from such waste, water from the top 20 m of the aquifer is unsuitable for human consumption. Given this situation and because children are highly vulnerable to environmental pollution, including exposure to toxic trace elements, this study focused on evaluating the exposure of children to arsenic (As), chromium (Cr), and mercury (Hg) in water. It also evaluated the relationship between the levels of these elements in water and their concentrations in urine and blood. Among the 33 children monitored in the study, arsenic surpassed WHO limits for blood in 37% of the cases, which could result from the ingestion of poultry contaminated with organoarsenic compounds. In the case of WHO limits for Mercury, 65% of the water samples analyzed, 28% of urine samples, and 12% of blood samples exceeded them. Mercury exposure was correlated with biological sex, some lifestyle factors, and the zone in Merida in which children live. These data suggest that the levels of some toxic metals in children may be affected by water source, socioeconomic factors, and individual behavior.

Seroprevalence of HPV 6, 11, 16 and 18 and correlates of exposure in unvaccinated women aged 16-64 years in Puerto Rico

Background

To understand risk factors for HPV exposure in Puerto Rican women, we evaluated HPV 6, 11, 16, and 18 serology in women aged living in the San Juan metropolitan area.

Methods

As part of a cross-sectional study, a population-based sample of 524 HPV unvaccinated Hispanic women ages 16–64 years completed face-to-face and computer assisted interviews and provided blood and self-collected anal and cervical specimens. Serology used multiplex virus-like particle based-IgG ELISA and HPV DNA was detected with L1-consensus PCR.

Results

32% and 47% were seropositive to HPV types included in the bivalent (16/18) and quadrivalent (6/11/16/18) vaccines, respectively. Type-specific seroprevalence was HPV6 − 29%, HPV11 − 18%, HPV16 − 23%, and HPV18 − 17%; seroprevalence was high in the youngest age-group (16–19: 26–37%). HPV seropositivity was associated with having ≥ 3 lifetime sexual partners (OR=2.5, 95% CI=1.7–3.9) and detection of anogenital HPV DNA (OR=1.8, 95% CI=1.2–2.6).

Conclusions

The high cumulative exposure of HPV vaccine types 6/11/16/18 in this Hispanic population was influenced by factors related to HPV exposure through sexual behavior. High seroprevalence in the youngest age-group indicates early age of exposure to HPV in Puerto Rico, highlighting the need for HPV vaccination starting prior to age 16.

Study of the intensification of solar photo-Fenton degradation of carbamazepine with ferrioxalate complexes and ultrasound

The intensification of the solar photo-Fenton system with ferrioxalate photoactive complexes and ultrasound applied to the mineralization of 15mg/L carbamazepine aqueous solution (CBZ) was evaluated. The experiments were carried out in a solar compound parabolic collector (CPC) pilot plant reactor coupled to an ultrasonic processor. The dynamic behavior of hydroxyl radicals generated under the different studied reaction systems was discussed. The initial concentrations of hydrogen peroxide and ferrous/oxalic acid and pH were found to be the most significant variables (32.79%, 25.98% and 26.04%, respectively). Under the selected optimal conditions ([H₂O₂]₀=150mg/L; [Fe²⁺]₀=2.5mg/L/[(COOH)₂]₀=12.1mg/L; pH=5) CBZ was fully degraded after 5min and 80% of TOC was removed using a solar photo-Fenton system intensified with ferrioxalate (SPFF). However, no improvement in the mineralization using SPFF process combined with ultrasound was observed. More mild pH conditions could be used in the SPFF system if compared to the traditional photo-Fenton (pH 3) acidic systems. Finally, a possible reaction pathway for the mineralization of CBZ by the SPFF system was proposed and therein discussed.

Water Consumption as Source of Arsenic, Chromium, and Mercury in Children Living in Rural Yucatan, Mexico: Blood and Urine Levels

Studies investigating the correlation between metal content in water and metal levels in children are scarce worldwide, but especially in developing nations. Therefore, this study investigates the correlation between arsenic, chromium, and mercury concentrations in drinking and cooking water and in blood and urine samples collected from healthy and supposedly non-exposed children from a rural area in Yucatan, Mexico. Mercury in water shows concentrations above the recommended World Health Organization (WHO) value for drinking and cooking water. Also, 25% of the children show mercury in urine above the WHO recommended value. Multivariate analyses show a significant role for drinking and cooking water as a vector of exposure in children. Also, the factor analysis shows chronic exposure in the case of arsenic, as well as an ongoing detoxification process through urine in the case of mercury. Further studies should be done in order to determine other potential metal exposure pathways among children.

What are sweet dreams made of? Analysis of psychoactive substances into “gummies”: A retrospective descriptive study

Introduction

Although psychoactive substances has a long history in recreational settings, research on its composition has focused only on tablets, crystal and powder, even though new formulation for new psychoactive substances are readily available for users.

Objectives

To describe the presence of psychoactive substances and its characteristics in new formulations which had not previously been found in samples delivered to Energy Control from 2014 to 2015 in Spain.

Methods

A total of 8324 samples were analysed from June 2014 to December 2015. Only those samples in gummy formulation were studied (n = 9). Samples were analyzed by energy control, a Spanish harm-reduction NGO that offers analysis of substances to users. Analysis was done by gas chromatography-mass spectrometry.

Results

From 9 samples of psychoactive substances in gummy formulation, the analysis detected that 55.5% contained multiple psychoactive substances: 6 samples contained 25N-NBOMe (66.7%), 1 2C-E (11.1%), 1 2C-D (11.1%). Two allylescaline (20%), 1 cocaine (11.1%), 1 THC (11.1%), 1 canabinol (11.1%), 1 ketamine (11.1%), 1 caffeine (11.1%), 1 MDMA (11.1%), 1 N-acetyl-MDMA (11.1%), 1 metoxetamine (11.1%), 1 N-acetyl-MDMA), 1 2C-N (11.1%). The only substance found in active dosage was 25N-NBOMe. Six samples (66.67%) did not contain the substance expected by the consumer.

Discussion

Incipient presence of gummies as new psychoactive formulation was found. The most prevalent drug was 25N-NBOMe; 66.7% did not contain the substance expected. This may pose a risk for potential harmful effects. All the gummies were known to be drug-carriers when bought. This could represent the presence of new formulations from June 2014 in the Spanish recreational market.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Mood disorders in HIV infection

Introduction

Psychiatric disorders, particularly mood disorders, have a profound effect on the use of and adherence to highly active antiretroviral therapy (HAART) among patients with human immunodeficiency virus (HIV) infection.

HIV infection and mood disorders have features in common, and each is a significant risk factor for the other.

Objective

The objective is to highlight the clinicians on the importance of screening and treating affective disorders among patients with HIV infection.

Methods

Two cases of HIV infected patients with comorbid mood disorder and torpid evolutions by poor adherence to treatment are reported.

A brief literature review on this subject is done.

Results

Major depression has been shown to alter the function of killer lymphocytes in HIV-infected patients and may be associated with the progression of HIV disease.

HIV-positive patients with mental disorders are less likely to receive and adherence to antiretroviral therapy.

First case-report: a man 52 years old, HIV-positive since 1985 with a comorbid bipolar disorder, with recurrent depressions and poor adherence to both treatment with a rapidly exitus laetalis.

Second case-report: man 45 years old, HIV-positive since 1992 with a comorbid depressive disorder, non-adhered to both therapy and HIV-associated dementia.

Conclusions

Depressive disorders are common in HIV infection. Antiretroviral regimens for HIV-infected patients require strict adherence. Untreated depression has been associated with medication nonadherence. Understanding the contribution of depression and its subsequent treatment on antiretroviral therapy adherence might direct clinicians toward earlier identification and more aggressive treatment among this population.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Demographic Characteristics of Personality Disorders in an Emergency Department

Objective

The aim of our study is to outline the demographic characteristics of the patients with a diagnosis of personality disorder that come to the ED. A second objective is to find specific risk factor for this type of patients.

Methods

We selected patients that came to the ED with the diagnosis of personality disorder, between October 2015 and February 2016. Data analysis was conducted using SPSS software. Chi2 test and t-Test were used as appropriate. A P-value < 0.05 was considered statistically significant.

Results

Sixty-eight of the 402 patients that were attended in the ED met the criteria of personality disorder; 44.92% of these patients presented with suicidal ideation or attempt. We found in the use of drugs, statistically significant differences between men and women, using drugs all the men with a personality disorder that came to the ED except one. The most frequent reason for consult were anxiety, conduct alterations, suicidal ideation, and suicidal attempt, being these consultations the 77%.

Conclusion

Anxiety and suicide risk are the most common reasons for a personality disorder patient to go to an ED. We have to be even more careful due to the high rate of suicide conducts in these patients. Also, it is important to think of drug use and dual pathology when assessing these patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Altered trafficking of abnormal prion protein in atypical scrapie: prion protein accumulation in oligodendroglial inner mesaxons

AIMS

Prion diseases exist in classical and atypical disease forms. Both forms are characterized by disease-associated accumulation of a host membrane sialoglycoprotein known as prion protein (PrPd ). In classical forms of prion diseases, PrPd can accumulate in the extracellular space as fibrillar amyloid, intracellularly within lysosomes, but mainly on membranes in association with unique and characteristic membrane pathology. These membrane changes are found in all species and strains of classical prion diseases and consist of spiral, branched and clathrin-coated membrane invaginations on dendrites. Atypical prion diseases have been described in ruminants and man and have distinct biological, biochemical and pathological properties when compared to classical disease. The purpose of this study was to determine whether the subcellular pattern of PrPd accumulation and membrane changes in atypical scrapie were the same as those found in classical prion diseases.

METHODS

Immunogold electron microscopy was used to examine brains of atypical scrapie-affected sheep and Tg338 mice.

RESULTS

Classical prion disease-associated membrane lesions were not found in atypical scrapie-affected sheep, however, white matter PrPd accumulation was localized mainly to the inner mesaxon and paranodal cytoplasm of oligodendroglia. Similar lesions were found in myelinated axons of atypical scrapie Tg338-infected mice. However, Tg338 mice also showed the unique grey matter membrane changes seen in classical forms of disease.

CONCLUSIONS

These data show that atypical scrapie infection directs a change in trafficking of abnormal PrP to axons and oligodendroglia and that the resulting pathology is an interaction between the agent strain and host genotype.

A test of basic psychological needs theory in young soccer players: time-lagged design at the individual and team levels

Within the framework of basic psychological needs theory (Deci & Ryan, 2000), multilevel structural equation modeling (MSEM) with a time-lagged design was used to test a mediation model examining the relationship between perceptions of coaches' interpersonal styles (autonomy supportive and controlling), athletes' basic psychological needs (satisfaction and thwarting), and indicators of well-being (subjective vitality) and ill-being (burnout), estimating separately between and within effects. The participants were 597 Spanish male soccer players aged between 11 and 14 years (M = 12.57, SD = 0.54) from 40 teams who completed a questionnaire package at two time points in a competitive season. Results revealed that at the individual level, athletes' perceptions of autonomy support positively predicted athletes' need satisfaction (autonomy, competence, and relatedness), whereas athletes' perceptions of controlling style positively predicted athletes' need thwarting (autonomy, competence, and relatedness). In turn, all three athletes' need satisfaction dimensions predicted athletes' subjective vitality and burnout (positively and negatively, respectively), whereas competence thwarting negatively predicted subjective vitality and competence and relatedness positively predicted burnout. At the team level, team perceptions of autonomy supportive style positively predicted team autonomy and relatedness satisfaction. Mediation effects only appeared at the individual level.

Growth Response of Eurotium chevalieri, Aspergillus fumigatus and Penicillium brevicompactum in Argentine Milk Jam

Milk jam ( dulce de leche) is a typical Argentine sweet spread prepared from milk concentrated by evaporation to about 70% w/w total solids at atmospheric pressure with added sucrose, glucose and vanillin. Growth of xerotolerant moulds represents a severe problem in this type of product with high sugar concentration. This work aimed at analysing the influence of water activity (aw range 0.74–0.85), pH (5.5 and 6.0) and the addition of 1,000 ppm potassium sorbate on Eurotium chevalieri, Aspergillus fumigatusand Penicillium brevicompactumgrowth response in milk jam stored at 25 °C or 35 °C during 90 days. Growth curves were successfully modelled by applying the modified version of Gompertz equation. There were proposed polynomials equations relating time to detection, λ, with two independent variables: potassium sorbate and water activity at pH 6.0. Some useful combinations of these factors were found to assure inhibition of mould growth during a critical storage period. Results might contribute to optimise manufacture conditions and/or milk jam composition to obtain a safer product when failure occurs during the hot filling process or when the product is stored for a long period of time.

Prevalence, genotyping, and correlates of anogenital HPV infection in a population-based sample of women in Puerto Rico

Background

Oncogenic HPV infection is associated to anogenital cancer. We estimate the prevalence and correlates of anogenital HPV infection among a population-based sample of women aged 16–64 years living in the metropolitan area of Puerto Rico.

Methods

564 women completed face-to-face and computer assisted interviews and self-collected anal and cervical specimens. HPV DNA testing used MY09/MY11 consensus HPV L1 primers and beta-globin as an internal control for sample amplification. Positive specimens were typed by dot-blot hybridization.

Results

Weighted prevalence of cervical, anal, and cervical/anal co-infection was 29.4%, 38.6%, and 17.1%, respectively. The commonest oncogenic HPV types detected in the cervix and anus were: 68 (8% vs. 7%) and 16 (5.5% vs. 5.1%), correspondingly. Having ≥3 lifetime sexual partners (OR: 2.3; 95% CI: 1.5–3.5) and last year anal intercourse (OR: 1.6; 95% CI: 1.1–2.5) increased the odds of anogenital HPV infection. Cervical infection was independently associated to anal infection (OR: 3.0; 95% CI: 2.0–4.6).

Conclusions

Similar to others, our results confirm the burden of anogenital HPV infection in women and its relationship with sexual behavior. As vaccination increases, future studies should monitor changing trends in HPV infection in this population, and the relationship between anal and cervical HPV-related disease.

Evolution of bipolar disorder over 12 years in a psychiatric hospital

Introduction

Bipolar disorder is a leading cause of hospitalization in psychiatric hospitals. It is known that early detection of bipolar disorder is associated with a better prognosis.

Objectives

The aim of this study is to conduct a demographic analysis of patients hospitalized for bipolar disorder in a single center between 2003 to 2014.

Methods

Retrospective cohort study of 1230 patients admitted with bipolar disorder diagnosis from 2003 to 2014 at Centre Assistencial Emili Mira i López of Parc Salut Mar of Barcelona. We divided the study in two periods: 2003–2008 and 2009–2014. We analyzed the following variables: frequency of admissions, age, sex and days of hospital stay, comparing both periods. Chi-square test for categorical variables and Student t test for quantitative variables were applied.

Results

The mean ages at the first and second period are 52 and 47, respectively (P < 0.001). There are no significant differences in sex and days of hospitalization. The frequency of admissions on the first and third trimesters is higher than in the second and fourth, although the differences are not statistically significant.

Conclusions

Despite the large number of patients in the study, there are limitations, such as being a retrospective study and not being adjusted for confounding factors. The average age of patients in the second period is lower than in the first. This could suggest an improvement in early detection of bipolar disorder in the last years. Further research is needed to confirm this hypothesis.

Disclosure of interest

LG is funded by the Instituto de Salud Carlos III(CM14/00111).

Manic episode associated with interferon alpha therapy: A case report

Interferon alpha is a cytokine with antiviral and antineoplastic action, which is commonly used for treatment of Hepatitis C and B, malignant melanoma, Kaposi's sarcoma, kidney cancer and certain hematologic diseases. It is well-known some of its neuropsychiatric symptoms such as depressive symptoms, cognitive impairment, chronic fatigue, dysphoria and anxiety, but there are also other less common like mania, psychotic symptoms and suicide risk that have been reported. These symptoms interfere in the quality of life very significantly, which at the end can affect treatment adherence.

We report a case of a 33-year-old man who was taken to the emergency department by his family referring nervousness, irritability, verbose, and insomnia during the last 5 days. The patient had not psychiatric history. He was diagnosed with a malignant melanoma stage III A a year ago which required to start interferon alpha treatment.

Patient and family tell that symptoms began after forgetting last interferon dose. In the psychopathology exploration, we could observe mood lability, delusion ideas of prosecution, which includes his entire family and autorreferentiality. In the emergency room the blood test, urine drug test and CT were normal.

During the admission, and in collaboration with the Oncology service, it was agreed the reintroduction and maintenance of interferon combined with olanzapine up to 30 mg/day and clonazepam up to 6 mg/day, which resulted in the resolution of symptoms in two weeks.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Analysis of risk factors for hydrocephalus development in newborn infants with germinal matrix hemorrhage

AIM

The aim of this study was to analyze risk factors for the development of hydrocephalus in newborn infants with germinal matrix (GM) hemorrhage.

METHODS

The study comprised 271 patients admitted to Carlos Haya University Hospital in Malaga with GM hemorrhage. The following data were recorded: gestational age, gender, twin birth, head circumference at birth, weight at birth, and Papile grade. Severe obstetrical (abruption, chorioamnionitis, pregnancy-induced hypertension, tocolytic treatment) and neonatal disorders (respiratory distress syndrome, neonatal infection, coagulation disorder, patent ductus arteriosus, necrotizing enterocolitis) were also recorded. Symptomatic hydrocephalus was diagnosed in the event of a progressive increase in head circumference and ventricular indices requiring shunting.

RESULTS

Of the 271 patients, 139 (51%) developed posthemorrhagic ventriculomegaly; 47 patients (17%) developed symptomatic hydrocephalus and needed shunt implantation. We found a significant relationship between the development of symptomatic hydrocephalus and Papile grade, lower gestational age, lower birth weight, twin birth, and neonatal infection.

CONCLUSION

Awareness of risk factors for the development of hydrocephalus in newborn infants with GM hemorrhage should be emphasized in order to enable an early diagnosis of ventriculomegaly and symptomatic hydrocephalus and thus make a correct therapeutic decision.

Diagnostic pathology in microbial diseases of sheep or goats

Post-mortem examination is a key step in the diagnostic process of infectious diseases in sheep and goats. Diagnostic pathology deals with identification and study of lesions, at the same time providing also significant clues regarding pathogenesis of the diseases. This article reviews the salient pathological findings associated with the most significant infectious diseases of sheep and goats present in countries where small ruminants are a relevant agricultural industry. Lesions are reviewed according to the different organ systems where they occur. Emphasis has been given in the description of the salient lesional patterns than can be identified in each organ and which can be of help in the differential diagnosis of the lesions caused by bacteria, viruses, fungi or prions. Finally, a review of the usefulness of ancillary tests that may be used on various tissue samples for performing an aetiological diagnosis, is included; the application of various techniques, from immunohistochemistry to molecular biology-based tests, is described.

Optimizing CIGB-300 intralesional delivery in locally advanced cervical cancer

BACKGROUND

We conducted a phase 1 trial in patients with locally advanced cervical cancer by injecting 0.5 ml of the CK2-antagonist CIGB-300 in two different sites on tumours to assess tumour uptake, safety, pharmacodynamic activity and identify the recommended dose.

METHODS

Fourteen patients were treated with intralesional injections containing 35 or 70 mg of CIGB-300 in three alternate cycles of three consecutive days each before standard chemoradiotherapy. Tumour uptake was determined using (99)Tc-radiolabelled peptide. In situ B23/nucleophosmin was determined by immunohistochemistry.

RESULTS

Maximum tumour uptake for CIGB-300 70-mg dose was significantly higher than the one observed for 35 mg: 16.1 ± 8.9 vs 31.3 ± 12.9 mg (P = 0.01). Both, AUC24h and biological half-life were also significantly higher using 70 mg of CIGB-300 (P < 0.001). Unincorporated CIGB-300 diffused rapidly to blood and was mainly distributed towards kidneys, and marginally in liver, lungs, heart and spleen. There was no DLT and moderate allergic-like reactions were the most common systemic side effect with strong correlation between unincorporated CIGB-300 and histamine levels in blood. CIGB-300, 70 mg, downregulated B23/nucleophosmin (P = 0.03) in tumour specimens.

CONCLUSION

Intralesional injections of 70 mg CIGB-300 in two sites (0.5 ml per injection) and this treatment plan are recommended to be evaluated in phase 2 studies.

[Compliance with the PECARN and AEP guidelines in diagnostic approach of mild head trauma in patients younger than 24 months old]

INTRODUCTION

Mild head trauma is a frequent complaint in Pediatric Emergency Departments. Several guidelines have been published in the last few years. However, significant variability can be appreciated in terms of the demand for image tests. The aim of this study is to determine the level of compliance with PECARN and AEP guidelines in the management of patients younger than 24 months old in four different hospitals.

PATIENTS AND METHODS

A multicenter retrospective study was conducted on patients presenting with mild head trauma between October 1st, 2011 and March 31st, 2013 in the Emergency Departments of four hospitals.

RESULTS

In the analysis of the results obtained, only one of the four hospitals complied with the AEP guidelines in more than 50% of the patients. The other three hospitals had a level of compliance lower than 50%. Management was more suitable according to PECARN guidelines, with 3 of the 4 hospitals having a level of compliance greater than 50%. However, the best compliance achieved by a hospital was only of 70%.

CONCLUSIONS

The study shows that the level of compliance with guidelines for management of mild head trauma in patients younger than 24 months old is low.

Influence of breed and genotype on the onset and distribution of infectivity and disease-associated prion protein in sheep following oral infection with the bovine spongiform encephalopathy agent

The onset and distribution of infectivity and disease-specific prion protein (PrP(d)) accumulation was studied in Romney and Suffolk sheep of the ARQ/ARQ, ARQ/ARR and ARR/ARR prion protein gene (Prnp) genotypes (where A stands for alanine, R for arginine and Q for glutamine at codons 136, 154 and 171 of PrP), following experimental oral infection with cattle-derived bovine spongiform encephalopathy (BSE) agent. Groups of sheep were killed at regular intervals and a wide range of tissues taken for mouse bioassay or immunohistochemistry (IHC), or both. Bioassay results for infectivity were mostly coincident with those of PrP(d) detection by IHC both in terms of tissues and time post infection. Neither PrP(d) nor infectivity was detected in any tissues of BSE-dosed ARQ/ARR or ARR/ARR sheep or of undosed controls. Moreover, four ARQ/ARQ Suffolk sheep, which were methionine (M)/threonine heterozygous at codon 112 of the Prnp gene, did not show any biological or immunohistochemical evidence of infection, while those homozygous for methionine (MARQ/MARQ) did. In MARQ/MARQ sheep of both breeds, initial PrP(d) accumulation was identified in lymphoreticular system (LRS) tissues followed by the central nervous system (CNS) and enteric nervous system (ENS) and finally by the autonomic nervous system and peripheral nervous system and other organs. Detection of infectivity closely mimicked this sequence. No PrP(d) was observed in the ENS prior to its accumulation in the CNS, suggesting that ENS involvement occurred simultaneously to that of, or followed centrifugal spread from, the CNS. The distribution of PrP(d) within the ENS further suggested a progressive spread from the ileal plexus to other ENS segments via neuronal connections of the gut wall. Differences between the two breeds were noted in terms of involvement of LRS and ENS tissues, with Romney sheep showing a more delayed and less consistent PrP(d) accumulation than Suffolk sheep in such tissues. Whether this accounted for the slight delay (∼5 months) in the appearance of clinical signs in Romney sheep is debatable since by the last scheduled kill before animals reached clinical end point, both breeds showed widespread accumulation and similar magnitudes of PrP(d) accumulation in the brain.

Pathology of SSLOW, a transmissible and fatal synthetic prion protein disorder, and comparison with naturally occurring classical transmissible spongiform encephalopathies

AIMS

Naturally occurring transmissible spongiform encephalopathies (TSEs) accumulate disease-specific forms of prion protein on cell membranes in association with pathognomonic lesions. We wished to determine whether synthetic prion protein disorders recapitulated these and other subcellular TSE-specific changes.

METHODS

SSLOW is a TSE initiated with refolded synthetic prion protein. Five terminally sick hamsters previously intracerebrally inoculated with third passage SSLOW were examined using light and immunogold electron microscopy.

RESULTS

SSLOW-affected hamsters showed widespread abnormal prion protein (PrP(SSLOW) ) and amyloid plaques. PrP(SSLOW) accumulated on plasma lemmas of neurites and glia without pathological changes. PrP(SSLOW) also colocalized with increased coated vesicles and pits, coated spiral membrane invaginations and membrane microfolding. PrP(SSLOW) was additionally observed in lysosomes of microglial cells but not of neurones or astrocytes.

CONCLUSIONS

PrP(SSLOW) is propagated by cell membrane conversion of normal PrP and lethal disease may be linked to the progressive growth of amyloid plaques. Cell membrane changes present in SSLOW are indistinguishable from those of naturally occurring TSEs. However, some lesions found in SSLOW are absent in natural animal TSEs and vice versa. SSLOW may not entirely recapitulate neuropathological features previously described for natural disease. End-stage neuropathology in SSLOW, particularly the nature and distribution of amyloid plaques may be significantly influenced by the early redistribution of seeds within the inoculum and its recirculation following interstitial, perivascular and other drainage pathways. The way in which seeds are distributed and aggregate into plaques in SSLOW has significant overlap with murine APP overexpressing mice challenged with Aβ.