Positive EIA Research Articles

The dark art of syphilis serology - an analysis of testing algorithms at a UK reference laboratory.

Introduction. Due to the complex nature of treponemal serology interpretation, testing algorithms vary across the UK.Gap statement. There is currently no gold standard method for interpretation of discordant serology results.Aim. To analyse serological response in early infection and to determine the best approach for discordant total antibody EIA and TPPA samples.Methodology. National reference laboratory serology and PCR (genital ulcer swabs) results from 2010 to 2017 were extracted from an electronic laboratory database.Results. A total of 24149 sera underwent analysis. Of syphilis PCR positive cases with contemporaneous sera, 33% (17/52) were IgM positive/equivocal, whilst all were EIA and TPPA positive. No sera with isolated IgM positivity (0/90) demonstrated seroconversion consistent with early treponemal infection, in contrast to 17% (2/12) of sera with isolated TPPA positivity. Isolated EIA positivity was observed in 6.2% (1499/24149) samples with the same result on repeat testing in 73% (154/211). In 100 samples with discordant EIA/TPPA results, IgG Immunoblot was more commonly positive (12/41, 29%) or equivocal (24/41, 59%), in those with a higher EIA antibody index, compared to those with a low antibody index, of which none tested positive and 2/3 (67 %) were equivocal.Conclusion. Isolated IgM positivity was not helpful in identifying early infection; isolated total antibody EIA positivity is unlikely to be a significant finding. IgG immunoblot testing was unable to determine clear treponemal antibody status in nearly half of all EIA/TPPA discordant samples.

Circulating Genotypes of Rotavirus Prior to Rotarix?vaccine Introduction in Kathmandu, Nepal.

In Nepal, it is estimated that about 3 million children under 5 years of age are prone to diarrhea and previous studies have shown rotavirus as the major etiological agent. Given the high burden of rotavirus, Rotarix® vaccine was introduced in the national immunization schedule in July 2020. This study was carried out in a tertiary health center from January- September 2018 to determine the burden of rotavirus diarrhea as well as genotypic variations in the circulating virus prior to vaccine introduction in Kathmandu, Nepal. Hospital based cross sectional study was conducted among children less than 5 years of age attending Kanti Children's Hospital. Rotavirus antigen detection was performed by enzyme immunoassay using ProSpecT Rotavirus Microplate Assay. Rotavirus A positive samples were further confirmed by genotyping using Reverse-Transcription Polymerase Chain Reaction. A total of 530 children that included 184 males and 346 females were enrolled in this study. Rotavirus antigen was detected in 112 (21.1%) stool samples. Of the total 112 positive EIA stool samples that were genotyped, G12P[6] (30.3%) was found to be the most common type, followed by G3P[8] (26.8%), mixed type (14.3%), and G1P[6] (13.4%). Continued surveillance should be carried out nationwide in Nepal to understand the effectiveness of the vaccination program and to report any new trends in the circulating genotypes.

An evaluation of the effect of the clinical features of patients and their used drugs on the false positive EIA test for HIV

An evaluation of the effect of the clinical features of patients and their used drugs on the false positive EIA test for HIV

781. C.difficile PCR+/ Toxin EIA- treat or not treat? A clinician survey

Background C.difficile Toxin Polymerase Chain Reaction (C.diff PCR) and C.difficile Toxin Enzyme Immunoassays (toxin EIA) are commonly used tests to diagnose Clostridoides difficile infection (CDI). C.diff PCR cannot differentiate between colonization and infection, leading to a higher false-positive diagnosis of CDI. Toxin EIA has low sensitivity leading to a missed diagnosis of CDI. In patients with C.diff PCR positive(+) and Toxin EIA negative(-), clinical judgment is often needed regarding the decision to treat or not to treat. C.diff cytotoxic assay (CCA), is a more sensitive method to detect the toxin but is time-consuming and not readily available.MethodsBetween 6/2019 and 12/2019, 83 patients who were admitted to the hospital, met our inclusion criteria (C.diff PCR+/EIA-). Clinicians who cared for these patients were contacted and surveyed with a predesigned questionnaire evaluating the rationale of treatment. Also, a simultaneous medical records review was done to ensure consistency. Along with this C.diff PCR+/EIA- stool samples were sent to ARUP laboratories for CCA. The CCA results were not available for clinicians and did not impact clinical care. Average cost for a CCA assay was $29ResultsDemographics of the clinicians were variable (Table 1). Several parameters were considered when making decisions regarding treatment and GI/ID were frequently involved (figure 1). Among the 83 patients, 41(49%) were CCA (+) and 42(51%) were CCA (-). 48 of 83 (58%) patients received treatment for CDI. 25 of 48 (52%) patients who were treated were CCA positive while 23 of 48 (48%) patients were CCA negative. Among the untreated patients, 16/35 (46%) were CCA+ while 19/35(54%) were CCA-. There was no statistically significant correlation between clinical judgment and CCA assay results (p: 0.56 on the Chi test).Demographics of the clinicians Clinician survey responses CDI Treatment and by CCA positivity ConclusionClinicians regardless of their background and training face challenges with the treatment of C.diff PCR+/EIA- patients. Patient outcomes based on the incorporation of CCA assay into an algorithm for C.diff PCR+/EIA- patients, need to be evaluated. But it has a potential role in stopping unnecessary CDI treatment as well as avoidance of missed treatment opportunities while possibly also being cost-effective.Disclosures Ank E. Nijhawan, MD, MPH, Gilead (Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support)

Impact of the introduction of nucleic acid amplification testing on Clostridioides difficile detection and ribotype distribution in Wales

ObjectivesTo determine the impact of the 2018 introduction of nucleic acid amplification tests (NAATs) for C. difficile detection on the laboratory diagnosis of C. difficile infection (CDI), and the distribution of C. difficile ribotypes. MethodsA retrospective analysis of five years (2015–2019) of C. difficile diagnostic laboratory and PCR ribotyping test results. ResultsA total of 255,104 diagnostic results, from 136,353 patients were analysed: 199,794 samples where glutamate dehydrogenase (GDH) was used as the primary screen; and 55,310 where NAATs were employed. An overall decrease in frontline positivity from 2015 to 2019 (10.3% [n = 5017] to 6% [n = 3190] - p < 0.0001) was observed, despite an increase in the number of samples tested (48,778 to 52,839). NAAT positivity was lower than GDH (p < 0.0001) for the two years where it was implemented. The variance was accounted for by increased overall C. difficile isolation and reduced toxin negative strain culture from NAAT positive samples (p < 0.0001). Ribotype distribution (6546 samples) remained stable with decreasing RT27 isolation in each year except 2017 (p < 0.0001). RT78 was associated with toxin A/B EIA positivity (p < 0.0001). ConclusionsUse of NAAT for the detection of C. difficile, as part of a 2-step algorithm, has not led to an increase in CDI laboratory diagnostic test positivity. In spite of ribotype distribution being comparable for screening in toxin A/B positive samples, there is a significantly greater correlation between NAAT positivity and culture of toxigenic strains compared to GDH.

4345 Two-step Algorithm for Clostridioides difficile is Inadequate for Differentiating Infection from Colonization in Children

OBJECTIVES/GOALS: In 2017, new guidelines recommended multi-step algorithms for CDI diagnosis, and clinical centers rapidly implemented changes despite limited pediatric data. We assessed a multi-step algorithm using NAAT followed by EIA for ability to differentiate symptomatic CDI from colonization in children. METHODS/STUDY POPULATION: We prospectively enrolled pediatric patients with cancer, cystic fibrosis, or inflammatory bowel disease who were not being tested or treated for CDI and obtained a stool sample for NAAT. If positive by NAAT (colonized), EIA was performed. Children with symptomatic CDI who tested positive by NAAT via the clinical laboratory were also enrolled and EIA performed on residual stool. A functional cell cytotoxicity neutralization assay (CCNA) was performed in addition. RESULTS/ANTICIPATED RESULTS: Of the 138 asymptomatic children enrolled, 24 (17%) were colonized. An additional 37 children with symptomatic CDI were enrolled. Neither EIA positivity (41% versus 21%, P = 0.11) or CCNA positivity (49% versus 46%, P = 0.84) were significantly different between symptomatic versus colonized children. When both EIA and CCNA were positive, children were more commonly symptomatic than colonized (33% versus 13%, P = 0.04). DISCUSSION/SIGNIFICANCE OF IMPACT: A multi-step testing algorithm with NAAT and EIA failed to differentiate symptomatic CDI from colonization in our pediatric cohort. As multi-step algorithms are moved into clinical care, pediatric providers will need to be aware of the continued limitations in diagnostic testing.

275. Delayed Diagnosis of Histoplasmosis in Pediatric Patients due to Atypical Clinical Presentations

BackgroundHistoplasmosis is a systemic mycosis with a wide range of clinical manifestations which represents a diagnostic challenge. It affects immunocompromised patients but also, previously healthy individuals that are exposed to a large inoculum of Histoplasma. The aim of our study was to describe the clinical presentation, epidemiologic features, laboratory/imaging findings and outcome of pediatric patients with histoplasmosis.Methodsa retrospective study including patients diagnosed as Histoplasmosis according to ICD-10 at a tertiary care center in Mexico City during 2009 to 2019. Clinical, epidemiological and laboratory/imaging data were gathered from each patient’s clinical file.Results5 patients with diagnosis of histoplasmosis were included; 2 patients were classified as proven with histopathologic confirmation, 2 patients as probable and 1 patient as possible according to the EORTC/MSG. The mean age of presentation was 7 years, 3/5 patients were male and 3/5 reported exposure to bats. Diagnosis was delayed by an average time of 6 months due to the variability of clinical presentations (progressive disseminated histoplasmosis, spinal histoplasmosis, cerebral histoplasmosis, intestinal histoplasmosis and mild acute pulmonary histoplasmosis). For the diagnosis, 1/5 had positive ELISA, 1/5 positive immunodiffusion (M band), 1/5 positive EIA in cerebrospinal fluid and 2/5 with histopathology findings that matched histoplasmosis. Pulmonary imaging with interstitial infiltrates in 4/5 and evidence of cavitation in one patient. Hemophagocytic syndrome was a complication in 1/5 and medullary syndrome was developed in the patient with spinal histoplasmosis which resolved with treatment. Liposomal amphotericin B was the treatment in 4/5, followed by itraconazole as the maintenance therapy.ConclusionThis study shows variable clinical presentations of Histoplasmosis which resulted in an important delay in diagnosis. This study highlights the importance of diagnostic suspicion in both healthy children and immunocompromised patients, always taking into account epidemiological risks such as exposure to bats.Disclosures All authors: No reported disclosures.

2373. Impact of a Change in Testing Strategy for Clostridioides difficile Infection on a Publicly Reported Metric and Treatment Days of Therapy

BackgroundIn an effort to optimize diagnostic testing for Clostridioides difficile infection (CDI) our health system changed from stand-alone PCR testing to a “2-step” approach wherein all positive PCR results reflexed to an EIA. We report the effects of this change on publicly reported CDI metrics and treatment days of therapy (DOT).MethodsThe setting includes 10 Cleveland Clinic Health System hospitals in northeast Ohio and one in Florida. On June 12, 2018, 9 NE Ohio hospitals changed from PCR alone to PCR followed by EIA. Stand-alone PCR testing remained at one and GDH / EIA / PCR for discordant for another. Testing volumes were obtained from the microbiology laboratory. C. difficile LabID event SIRs were obtained from NHSN. Public reporting interpretative categories were identified based on SIR for second half of 2018. DOT for CDI agents were obtained from an antimicrobial stewardship database.ResultsAmong hospitals that changed strategy the volume of PCR testing and the percent PCR + was similar between time periods. EIA positivity ranged from 23% to 53%. 4/11 hospitals improved their public reporting category: 3/9 that changed testing strategy and 1/2 that did not (Table 1). Two of 3 that changed strategy and improved public reporting also had a decrease in DOT. DOT increased in the 2 hospitals that did not change strategy.ConclusionSix months after adopting a 2-step CDI testing strategy 7 of 9 hospitals had a lower SIR with 3 also demonstrating an improvement in public reporting category favorably impacting reputational and reimbursement risk for our healthcare system. CDI agent DOT was similar before and after the change. The impact of choice of test on publicly reported metrics demonstrates the difficulty of utilizing a proxy for hospital onset CDI, the CDI LabID event, as a measure of quality of care provided. Disclosures All authors: No reported disclosures.

Potential false-positive urine Legionella enzyme immunoassay test results.

The objective of this study was to identify potential false-positive urine Legionella pneumophila (Legionella) enzyme immunoassay test results. A total of 107 consecutive patients with positive EIA tests were retrospectively analyzed over a 34-month period. Concurrent blood, urine, and sputum cultures, as well as chest radiographic findings, were reviewed in these patients. Twenty patients (19%) had no radiographic evidence of pulmonary disease despite a positive EIA test. In those 20 patients, 14 also had growth of non-Legionella bacteria. Of patients with an infiltrate or opacity on chest imaging, only 27 had Legionella sputum cultures obtained, with Legionella culture growth occurring in 7 (26%). Nine other patients had negative Legionella sputum cultures but the growth of another pathogenic organism in blood, sputum, and/or urine cultures. Pseudomonas aeruginosa was the most common organism isolated, found in 20% of patients in the entire cohort. Twenty-five patients (23%) were characterized as having probable false-positive Legionella urinary antigen EIA testing, and an additional 17 patients (16%) were characterized as having possible false-positive Legionella EIA tests. Our findings suggest that urine Legionella EIA tests may lead to a substantial number of cases being misdiagnosed as Legionaries' disease in patients with non-Legionella bacterial colonization or infection.

THUR 007 A garden variety neuropathy

A 47 year old with subacute onset of walking difficulties, asymmetric lower limb and facial weakness and areflexia was admitted as a suspected case of Guillain-Barre syndrome. Clinical examination revealed left lower motor neuron facial weakness, right upper limb and lower limb weakness and a suspended area of pain and allodynia at T7. Structural imaging of the brain and spine was normal. CSF protein was elevated with pleocytosis. Nerve conduction studies was suggestive of proximal demyelinating polyradicular neuropathy. The clinical suspicion of neuroborreliosis was confirmed in CSF with Borrelia VlsE antigen positivity and serum Borrelia Burgdorferi IgG EIA positivity. The patient had no recollection of tick exposure but did recall a presumed horsefly bite on the forearm two weeks earlier of uncertain significance. This is a case of Bannwarth syndrome - meningoradiculoneuritis due to neuroborreliosis endemic in Northern Europe. Our patient was treated with Ceftriaxone with rapid improvement of symptoms. This case highlights the importance of careful history taking including ascertainment of travel to Borrelia endemic areas and recognition of this eminently treatable meningoradiculoneuropathy.

Toxin positivity and tcdB gene load in broad-spectrum Clostridium difficile infection.

This study aimed to evaluate the clinical significance of toxin positivity and toxin gene load, and the relation between them in the broad spectrum of Clostridium difficile infection (CDI) including colonization, significant diarrhea, and severe disease. We included 2671 fecal samples submitted for CDI diagnosis and 180 samples from healthy individuals. The clinical spectrum was categorized as category I (toxigenic C. difficile positive without clinical CDI criteria), category II (mild CDI), and category III (severe CDI). Clinical parameters were compared based on toxin EIA and tcdB C t values. C t values of tcdB PCR for predicting toxin EIA positivity were assessed using receiver-operating characteristic (ROC) curves. The median C t values of tcdB PCR and toxin positivity were not significantly correlated with clinical spectrum of CDI (27.5, 28.2, and 26.1 for tcdB C t and 55.0, 56.6, and 60.9% for toxin EIA positivity in category I, II, and III, respectively, P>0.05). There were significant differences in the tcdB C t values between toxin EIA-positive and -negative groups (P<0.001). Optimal cutoff for the tcdB C t value for estimating toxin EIA positivity was 26.3 with 79.3% sensitivity and 83.6% specificity with good area under the curves (AUC, 0.848). The C t values successfully predicted toxin EIA positivity and could be used as a surrogate for toxin EIA positivity in the diagnostic algorithm and routine analysis. Further studies are needed to validate the clinical significance of tcdB PCR C t value in toxigenic C. difficile colonization and infection.

Toxin Detection by Cell Culture Neutralization Assay [CYT] and Toxin based EIA [Tox EIA] among Recurrent Episodes of CDI Diagnosed by PCR

BackgroundThe Ad Hoc C. difficile surveillance working group defines recurrent C. difficile infection as a second episode occurring >8 weeks after the index case. Due to its high sensitivity, diagnosis of recurrent CDI by PCR is extremely challenging in patients who may have persistent, PCR detectable shedding of toxigenic C. difficile (TCD) for an extended period of time after treatment of the initial CDI episode. CYT, which detects C. difficile toxin antigen, is a cumbersome test to perform but is considered as the current clinical diagnostic gold standard for CDI diagnosis. Aim: To determine the CYT and Toxin A/B EIA positivity among patients with recurrent CDI episodes detected by PCR. We further characterized the performance of diagnostic tests based on whether the recurrent episode was a relapse or reinfection.MethodsDuring a three month study period, CYT and Tox A/B EIA was performed on consecutive stool samples submitted from PCR positive recurrent episodes of CDI. For the purpose of this study, recurrence was defined as a second episode of CDI that occurred within 120 days from the most recent episode. MLST analysis was performed as previously described to characterize relapse and reinfection among the recurrent episodes (2).ResultsThirty-five recurrent episodes occurred over the study period. 21/35 [60%] were positive by CYT and 12/35 [34%] by Tox A/B EIA. Among the recurrent CDI episodes, 16 (46%) were genotypical confirmed as relapse with the original infecting strain. Majority of these relapses were positive by CYT (81%) when compared with Tox EIA (43%). Among patients with geno typically confirmed reinfection (n = 8), CYT and EIA positivity was 63 % and 50 % respectively. For the remaining 11 episodes, TCD was not retrievable in culture, CYT and EIA positivity among this group was 27 % and 9 % respectively.ConclusionForty percent of recurrent CDI episodes detected by PCR could not be confirmed by CYT. EIA missed 66 % of CYT positive recurrent CDI. The performance of CYT and EIA varied among recurrences due to relapse and reinfection. These results have significant implication for reporting of CDI HAI rates.Disclosures All authors: No reported disclosures.

Follow-up Evaluation of Air Force Blood Donors Screening Positive for Chagas Disease

Background Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is endemic to Texas and has significant morbidity associated with its cardiac pathology. The Joint Base San Antonio-Lackland (JBSA) represents a healthcare system with universal coverage to its beneficiaries and its blood bank screens all first-time blood donors for T. cruzi infection. Although there is a published, standardized approach for diagnosis and evaluation of Chagas disease in the United States, adherence to this approach has not been studied.Methods A retrospective chart review was performed on all persons who screened positive for T. cruzi on blood donation at JBSA from 2014 to 2016. Charts were reviewed to determine frequency and results of confirmatory testing, history and physical, EKG, and 30 second rhythm strip; outcomes of these evaluations were ascertained. Chagas disease was considered confirmed on the basis of positive EIA and TESA testing from the CDC and/or two different positive serologic tests.ResultsOf the 43,402 blood donors at JBSA, 23 screened positive for Chagas disease. Follow-up information was available on 22 (95.7%). Seventeen (77%) were military trainees and 18 (82%) were male. Patients had a mean of 2.5 (range 1–5) additional serologic tests, with 13 different combinations of confirmatory tests ordered, including 17 (77%) who had the initial screening test repeated. Two patients (9%), both from Texas, met criteria for Chagas disease. One of these was diagnosed with cardiomyopathy and underwent administrative separation from the Air Force. Eleven (50%) had Chagas disease excluded on the basis of two negative follow-up tests, and 9 (41%) had one negative follow-up test. All underwent history and physical, 15 (68%) had an EKG, and 5 (22%) had a 30 second rhythm strip. Fourteen (64%) were referred to infectious diseases.Conclusion Among a small cohort of active duty service members who screened positive for T. cruzi infection on blood donation, diagnostic workup, and evaluation varied considerably, despite universal access to no-cost medical care within a single system. Opportunities exist within the military health system to decrease heterogeneity and to improve evaluation of persons who screen positive in the future.Disclosures H. Yun, American Board of Internal Medicine, Infectious Disease Board: Board Member, travel reimbursement, honorarium

Loss to Follow-Up from HIV Screening to ART Initiation in Rural China.

BackgroundPatients who are newly screened HIV positive by EIA are lost to follow-up due to complicated HIV testing procedures. Because this is the first step in care, it affects the entire continuum of care. This is a particular concern in rural China.Objective(s)To assess the routine HIV testing completeness and treatment initiation rates at 18 county-level general hospitals in rural Guangxi.MethodsWe reviewed original hospital HIV screening records. Investigators also engaged with hospital leaders and key personnel involved in HIV prevention activities to characterize in detail the routine care practices in place at each county.Results699 newly screened HIV-positive patients between January 1 and June 30, 2013 across the 18 hospitals were included in the study. The proportion of confirmatory testing across the 18 hospitals ranged from 14% to 87% (mean of 43%), and the proportion of newly diagnosed individuals successfully initiated antiretroviral treatment across the hospitals ranged from 3% to 67% (mean of 23%). The average interval within hospitals for individuals to receive the Western Blot (WB) and CD4 test results from HIV positive screening (i.e. achieving testing completion) ranged from 14–116 days (mean of 41.7 days) across the hospitals. The shortest interval from receiving a positive EIA screening test result to receiving WB and CD4 testing and counseling was 0 day and the longest was 260 days.ConclusionThe proportion of patients newly screened HIV positive that completed the necessary testing procedures for HIV confirmation and received ART was very low. Interventions are urgently needed to remove barriers so that HIV patients can have timely access to HIV/AIDS treatment and care in rural China.

Evaluation of flow cytometric HIT assays in relation to an IgG-Specific immunoassay and clinical outcome.

Heparin-induced thrombocytopenia (HIT) is a severe side effect of heparin treatment caused by platelet activating IgG antibodies generated against the platelet factor 4 (PF4)-heparin complex. Thrombocytopenia and thrombosis are the leading clinical symptoms of HIT. The clinical pretest probability of HIT was evaluated by the 4T score system. Laboratory testing of HIT was performed by immunological detection of antibodies against PF4-heparin complex (EIA) and two functional assays. Heparin-dependent activation of donor platelets by patient plasma was detected by flow cytometry. Increased binding of Annexin-V to platelets and elevated number of platelet-derived microparticles (PMP) were the indicators of platelet activation. EIA for IgG isotype HIT antibodies was performed in 405 suspected HIT patients. Based on negative EIA results, HIT was excluded in 365 (90%) of cases. In 40 patients with positive EIA test result functional tests were performed. Platelet activating antibodies were detected in 17 cases by Annexin V binding. PMP count analysis provided nearly identical results. The probability of a positive flow cytometric assay result was higher in patients with elevated antibody titer. 71% of patients with positive EIA and functional assay had thrombosis. EIA is an important first line laboratory test in the diagnosis of HIT; however, HIT must be confirmed by a functional test. Annexin V binding and PMP assays using flow cytometry are functional HIT tests convenient in a clinical diagnostic laboratory. The positive results of functional assays may predict the onset of thrombosis. © 2016 International Clinical Cytometry Society.

Characteristics of Clostridium difficile infection in patients with discordant diagnostic test results.

Clinical features of Clostridium difficile infection (CDI) cases diagnosed by detection of polymerase chain reaction (PCR), with negative toxin enzyme immunoassay results (EIA) have not been fully elucidated. The purpose of this study was to determine the magnitude of CDI patients who had negative EIA toxin determinations but positive PCR tests, and their differences in clinical presentation. We performed a retrospective study comparing the clinical features of CDI cases detected by EIA (toxins A + B) with cases detected by PCR (toxin negative, PCR positive) over a 16-month period. Only patients with an initial Clostridium difficile infection episode that fulfilled a standardized definition were included. During the study period, 107 episodes of CDI were detected. Seventy-four patients (69%) had positive glutamate dehydrogenase (GDH) antigen and EIA determinations (EIA positive patients). Thirty-three patients (31%) had GDH positive, negative toxin EIA and positive PCR determination (PCR positive patients). PCR positive patients were younger, 57 (27) years (mean [SD]), than EIA positive patients, 71 (16) years, (p < 0.001). Fewer PCR positive patients were receiving proton pump inhibitors (21 patients, 64%) than EIA positive patients (61 patients, 82%, p = 0.034). The clinical presentation was similar in both groups. In the multivariate analysis, lower age was identified as the only independent variable associated with PCR positive patients. One third of Clostridium difficile infection patients present negative toxin EIA and PCR positive tests. Performing PCR determination after the negative EIA test is more relevant in younger patients.

PTU-260 Pcr and toxin eia in diagnosing and predicting outcome of clostridium difficile infection in an island population: Abstract PTU-260 Table 1

Introduction Clostridium difficile infection (CDI) can be life-threatening, with an estimated mortality of up to 15%. The clinical significance of a positive PCR test in CDI remains unclear. We compared clinical characteristics, inflammatory markers and mortality in CD toxin positive patients with toxin negative, PCR positive individuals. We also aimed to identify risk factors associated with the development of toxin positive CDI. Method A retrospective case-control study was conducted at the Jersey General Hospital of patients who developed CDI between 2008 and 2012. For each toxin positive case, 2 age/sex/ward/period-matched controls without diarrhoea were selected randomly. 131 toxin negative, GDH positive samples had PCR using Cepheid Xpert. Patient demographics, clinical characteristics and 30 day case-fatality rate were collated. Results During the study, 207 patients were toxin positive, 92 PCR positive and toxin negative and 39 had a stool sample negative by both toxin and PCR testing. A positive toxin EIA stool sample was associated with both significantly higher WCC (14.5 × 10 9 /L versus 11.3 × 10 9 /L, p = 0.003) and CRP (114.7 mg/dL versus 82.9 mg/dL, p = 0.001) but PCR positivity was not (p > 0.05). A positive toxin EIA test was a significant independent predictor of death (OR: 1.89 [95% CI: 1.0–3.4], p = 0.046) but a positive NAAT in the absence of EIA-detectable toxin was not (OR: 1.0 [95% CI: 0.3–3.1], p = 1.0). Multivariate analysis demonstrated that alcoholic/liver disease (p = 0.042), urinary tract infection (p = Conclusion In toxin negative CDI, PCR neither predicts disease severity nor mortality. However, it may have a role in disease surveillance and infection control. Judicious use of antibiotics and PPIs can play an important role in the prevention of CDI. Disclosure of interest None Declared.

Do not lose sight of syphilis

Ocular manifestations of syphilis are uncommon and typically occur during the secondary stage of the disease, causing significant sequelae if left untreated. This is an unusual presentation of syphilis in a 36-year-old man. He was referred by his optometrist to an ophthalmologist with a five day history of central and para-central bilateral visual field loss preceded by two days of photopsia. There were no other accompanying symptoms, including headache, nausea, ocular pain, nor other focal neurological deficits. However, he had experienced a Jarisch-Herxheimer reaction after receiving cefazolin prophylaxis prior. On examination, he had greatly reduced vision in both eyes, markedly on the left eye with acuity of 6/60 and bilateral optic discs swelling. He had negative HIV, hepatitis B and C serology, but syphilis serology had positive RPR, EIA and TPHA. MRI examination of the brain and orbits was unremarkable except for inflammatory changes in the mastoids. A diagnosis of bilateral treponemal optic neuritis was made, and he was commenced on oral prednisone for 3 days and intravenous penicillin G for 2 weeks and his visual acuity improved markedly.

First clinical and microbiological characterization of Clostridium difficile infection in a Croatian University Hospital

Clinical background and molecular epidemiology of Clostridium difficile infection (CDI) in the University Hospital Centre Split were investigated from January 2010 to December 2011. In total, 54 patients with first episode of CDI were consecutively included in the study based on the positive EIA test specific for A and B toxins. Demographic and clinical data were prospectively analyzed from medical records. CDI incidence rate was 0.6 per 10,000 patient-days. Thirty six cases (70.6%) were healthcare-associated, twelve cases (23.5%) were community-associated and three (5.9%) were indeterminate. Six patients (11.7%) had suffered one or more recurrences and 37 patients (72.5%) showed severe CDI. Prior therapy with third generation cephalosporin was significantly associated with severe CDI (P < 0.021). Fifty four toxigenic C. difficile strains were isolated and 50 of them were available for PCR-ribotyping. Sixteen different PCR-ribotypes were identified. The most prevalent were PCR-ribotype 001 (27.8%) and 014/020 (24.1%). Twenty three strains were resistant to at least one of the antibiotics tested. Among resistant strains, three (13.0%) – all PCR-ribotype 001 – were multi-resistant. Resistance to fluoroquinolones was significantly higher in strains that caused infection after previous use of fluoroquinolones (P = 0.04).

Clostridium difficile 027 infection in Central Italy

BackgroundClostridium difficile (CD) has increasingly become recognised as a significant international health burden, often associated with the healthcare environment. The upsurge in incidence of CD coincided with the emergence of a hypervirulent strain of CD characterized as 027.In 2010, 8 cases of CD 027 infections were identified in Italy. Since then, no further reports have been published. We describe 10 new cases of CD 027 infection occurring in Italy.MethodsSince December 2010, stool samples of patients with severe diarrhea and clinical suspicion of the presence of a hypervirulent strain, were tested for CD 027 by the Xpert C. difficile PCR assay (Cepheid, Sunnyvale, CA). Clinical, epidemiological and laboratory data were collected.ResultsFrom December 2010 to April 2012, 24 faecal samples from 19 patients who fit the above criteria were submitted to our laboratory. Samples were collected from 7 different hospitals.Of these, 17 had a positive PCR for CD and 10 were the epidemic 027 strain (59%). All PCR positive samples had a positive EIA toxin A/B test. Nine of 10 patients were recently exposed to antimicrobials and were healthcare-associated, including 4 with a history of long term care facility (LTCF) admission; the remaining case was community-associated, namely the wife of a patient with hospital-acquired CD 027 infection. Five patients experienced at least one recurrence of CD associated diarrhea (CDAD) with a total of 12 relapsing episodes. Of these, two patients had 5 and 6 relapses respectively.We compared the 10 patients with 027 CDAD versus the 7 patients with non-027 CDAD. None of the 7 patients with non-027 CDAD had a recent history of LTCF admission and no subsequent relapses were observed (p = 0.04).ConclusionsOur study shows that CD 027 is emerging in healthcare facilities in Italy. Whilst nosocomial acquisition accounted for the majority of such cases, 4 patients had history of a recent stay in a LTCF. We highlight the substantial risks of this highly transmissible organism in such environments. Moreover, 50% of our patients with CDAD from the 027 strain had high relapse rates which may serve to further establish this strain within the Italian health and social care systems.