Diagnostic utility of hepatitis E virus antigen-specific ELISA versus PCR testing in a cohort of post liver transplant patients in a large university hospital.

BACKGROUND: Hepatitis E virus (HEV) is an important infectious agent causing acute and chronic disease. Chronic hepatitis E affects immunocompromised people and serological testing is neither reliable nor sufficient to infer whether a patient has infection; therefore HEV RNA testing is the only reliable diagnostic test presently available. An HEV antigen-specific ELISA test is commercially available but is not yet in clinical use. OBJECTIVES: 1) determine the prevalence of HEV infection in the Royal Free Hospital (RFH) liver transplant cohort; 2) compare the diagnostic utility of HEV antigen-detection against the current gold standard; 3) consider screening strategies for HEV infection in immunocompromised groups. STUDY DESIGN: The serum samples of 490 post liver transplant patients visiting the outpatient clinic at the RFH over an eight-month period were tested for HEV with both an HEV antigen-specific ELISA and HEV RNA test. RESULTS: The prevalence of HEV infection was 0.20% (95% CI 0.0%-1.1%). The specificity of the ELISA was 98.2% with a positive predictive value of 10.0%. There was one true positive HEV case, which was picked up correctly by the antigen-specific ELISA. These results were improved by incorporating a neutralisation step into further ELISA tests. CONCLUSIONS: The antigen-specific ELISA test gave no false negative results, supporting its utility as a screening tool. There was one true antigen positive result. Further investigation including cost analysis is indicated to determine the efficacy of HEV antigen-specific ELISA testing in a screening context and in the clinical investigation of HEV infection in immunocompromised patients.

Cytomegalovirus pre-emptive therapy after hematopoietic stem cell transplantation in the era of real-time quantitative PCR: comparison with recipients of solid organ transplants.

BACKGROUND: Cytomegalovirus (CMV) continues to be an important complication of hematopoietic stem cell transplantation and solid organ transplantation. METHODS: In this study, 314 patients who underwent hematopoietic stem cell transplantation between January 2003 and October 2011 were tested serially for CMV DNA by real-time quantitative polymerase chain reaction (qPCR) for 90 days post transplantation. Patients with CMV viremia >3000 genomes/mL (equivalent to 2520 IU/mL) received pre-emptive therapy and were compared with previously published data from solid organ transplant (SOT) patients monitored and treated in exactly the same way. RESULTS: After stem cell transplant (SCT), 48% of patients developed at least 1 episode of viremia. The median duration of a viremic episode was 25 days and the peak viral load (VL) was 4784 genomes/mL whole blood (equivalent to 4019 IU/mL). The data demonstrated that recipients with positive CMV serostatus were at increased risk of developing viremia, with 0% of donor-negative/recipient-negative (D-R-), 3.7% of D+R-, 79.5% of D-R+, and 74.2% of D+R+ groups developing viremia over follow-up (adjusted hazard ratio for D+R- vs. D+R+ group 0.03; 95% confidence interval 0.004, 0.18; P = 0.0013). In contrast with SOT patients, where 58/74 (78%) D+R- patients had viremia, a low risk of CMV infection was seen after stem cell transplantation (1/27; 3.7%). CONCLUSION: As both groups of patients, the previously published SOT patients and the present hematopoietic SCT patients, were monitored using the same protocol and qPCR assay with pre-emptive therapy administered at the same VL cutoffs, the distinct differences seen cannot be explained by differences in testing or management and thus emphasize distinct aspects of the natural history of CMV infection post transplant in these 2 patient groups.

Comparison of five commercially available immunochromatographic tests for the detection of norovirus in faecal specimens.

Five CE-marked immunochromatography assay kits for the rapid detection of norovirus were compared with the reference method of real-time polymerase chain reaction (PCR) for the detection of acute norovirus infection. The sensitivity of the assays ranged between 23% and 59% with specificity being 75‒100% when compared with real-time PCR. The data suggest that a reactive immunochromatographic assay indicates norovirus infection. However, the sensitivity of the assay would need to be significantly improved to be suitable for routine diagnostic purposes or as an alternative to laboratory analysis for near-patient testing.

Educating K-12 Professionals and Parents: Finding Health Information for Special Needs Children.

A successful partnership model between an academic health sciences library and a K-12 school district to provide librarians, nurses, and special education staff with access to health information to support special needs children and their parents is presented. Train-the-trainer staff sessions and a parent session were collaboratively developed. Funding support was used to purchase iPads for librarians and nurses to deliver mobile support. The results indicate the resources taught are being used to find health information and the school librarians and nurses are being sought after to assist in finding health information. Positive feedback from the school district indicates this model could be replicated in similar settings.

The utility of genotypic tropism testing in clinical practice.

A review of a large number of HIV-1 tropism test requests (n = 1148) performed at a London tertiary referral centre was carried out. The aim was to establish whether these were being performed in line with recommendations from published guidelines and whether this represented the most cost-effective use of these tests in informing prescribing decisions of the CCR5 antagonist drug, maraviroc. The cost of these assays within the UK was covered by commercial funding until April 2013 which has subsequently been withdrawn. Furthermore, all healthcare settings are under increasing cost constraints and hence establishing the real utility and appropriate use of these tests is of vital importance.

Isolated to integrated: an evolving medical informatics curriculum.

A library-led introductory informatics theme has been part of the Albany Medical College undergraduate medical school curriculum as a concurrent theme since 1993. Initially, classes were limited to large group sessions focusing on general searching skills. Over the past several years, course content has been expanded and increasingly integrated into other themes and clerkships. Web-based self-paced tutorials have replaced many classroom sessions, and Web 2.0 technologies have been introduced. Collaborations with clinical and basic science faculty in other themes supplement and strengthen the theme.

Factors influencing PCR detection of viruses in cerebrospinal fluid of patients with suspected CNS infections.

BACKGROUND: Polymerase chain reaction (PCR) is used to detect viruses in the cerebrospinal fluid (CSF) of patients with neurological disease. However, data to assist its use or interpretation are limited. OBJECTIVE: We investigated factors possibly influencing viral detection in CSF by PCR, which will also help clinicians interpret positive and negative results. METHODS: CSF from patients with was tested for human herpesviruses types 1-6, JC virus, enteroviruses, and Toxoplasma gondii. The likelihood of central nervous system (CNS) infection was classified as likely, possible, or unlikely. PCR findings in these categories were compared using single variable and logistic regression analysis. RESULTS: Of 787 samples tested, 97 (12%) were PCR positive for one or more viruses. Of episodes likely to be CNS viral infections, 30% were PCR positive compared to 5% categorised as unlikely. The most frequent positive findings were Epstein Barr virus (EBV), enteroviruses, and herpes simplex virus (HSV). Enteroviruses and HSV were found predominantly in the likely CNS viral infection group, whereas EBV was found mainly in the unlikely group. Positive PCR results were more likely when there were 3-14 days between symptom onset and lumbar puncture, and when CSF white cell count was abnormal, although a normal CSF did not exclude a viral infection. CONCLUSIONS: The diagnostic yield of PCR can be maximised by using sensitive assays to detect a range of pathogens in appropriately timed CSF samples. PCR results, in particular EBV, should be interpreted cautiously when symptoms cannot readily be attributed to the virus detected.

An in situ study of the effect of nitrate on the reduction of trichloroethylene by granular iron.

The effect of nitrate on the reduction of TCE by commercial granular iron was investigated in column experiments designed to allow for the in situ monitoring of the iron surface film with Raman spectroscopy. Three column experiments were conducted; one with an influent solution of 100 mg/l nitrate+1.5 mg/l TCE, and two control columns, one saturated directly with 100 mg/l nitrate solution, the other pre-treated with Millipore water prior to the introduction of a 100 mg/l nitrate solution. In the presence of nitrate, TCE adsorbed onto the iron, but there was little TCE reduction to end-products ethene and ethane. The iron used (Connelly, GPM, Chicago) is a product typical of those used in permeable granular iron walls. The material is covered by an air-formed high-temperature oxidation film, consisting of an inner layer of Fe(3)O(4), and an outer, passive layer of Fe(2)O(3). In the control column pre-treated with Millipore water, the passive Fe(2)O(3) layer was removed upon contact with the water in a manner consistent with an autoreduction reaction. In the TCE+nitrate column and the direct nitrate saturation column, nitrate interfered with the removal of the passive layer and maintained conditions such that high valency protective corrosion species, including Fe(2)O(3) and FeOOH, were stable at the iron surface. The lack of TCE reduction is explained by the presence of these species, as they inhibit both mechanisms proposed for TCE reduction by iron, including catalytic hydrogenation, and direct electron transfer.

Sampling and Raman confocal microspectroscopic analysis of airborne particulate matter using poly(dimethylsiloxane) solid-phase microextraction fibers.

Commercial poly(dimethylsiloxane) (PDMS) 7-microm solid-phase microextraction (SPME) fibers were used for sampling and Raman spectroscopic analysis of a tailpipe diesel exhaust, candle smoke, cigarette smoke, and asbestos dust. Samples were collected via direct exposure of the SPME fiber to contaminated air. The mass loading for SPME fibers was varied by changing the sampling time. Results indicate that PDMS-coated fibers provide a simple, fast, reusable, and cost-effective air sampling tool for airborne particulates. The PDMS coating was stable; Raman bands of the PDMS coating were observed exactly at the same wavenumber positions before and after air sampling. Raman spectroscopic analysis resulted in identification of several characteristic bands allowing chemical speciation of particulates. The advantage of the SPME fiber is the open bed geometry allowing for application of various spectroscopic methods of particulate analysis. This paper describes the first-ever combined application of SPME technology with Raman confocal microspectroscopy for sampling and analysis of airborne particulates. Advantages of the combination of solid-phase microextraction and Raman microspectroscopy for airborne particulate analysis are discussed. Challenges associated with combined SPME sampling and Raman analysis of single particles are also described.

Identification of hepatitis C virus seroconversion resulting from nosocomial transmission on a haemodialysis unit: implications for infection control and laboratory screening.

Hepatitis C virus (HCV) seroconversion was detected by routine screening in a haemodialysis patient, Patient 1. Serological investigations were undertaken over the following 3 months to determine if further transmission to other patients on the unit had occurred. No additional cases were identified. Twenty-two haemodialysis patients known to have HCV infection were investigated using molecular epidemiological methods to determine if transmission between patients had occurred. HCV viraemia was demonstrated by polymerase chain reaction in 19 of 22 patients (86%). Genotyping showed that eight patients were infected with genotype 1, three with genotype 3 and eight, including Patient 1, with genotype 2. Phylogenetic analysis of viral sequences from the eight patients with genotype 2 revealed three, including Patient 1,with a novel subtype of HCV type 2, and revealed close similarity between viral sequences from patient 1 and those from one other patient, suggesting transmission. This was consistent with haemodialysis histories. Among other patients with genotype 2, there were two with subtype 2a and three others with three separate novel subtypes, as yet undesignated. With the exception of patient 1, all patients infected with novel subtypes were of Afro-Caribbean origin. The HCV prevalence among patients on the haemodialysis unit was high (14%), which may reflect the ethnicity of our haemodialysis population. This case emphasises the risk of nosocomial transmission and the importance of infection control procedures on haemodialysis units, and highlights the usefulness of molecular epidemiological techniques for the investigation of outbreaks of HCV infection.

Control of an outbreak of an epidemic methicillin-resistant Staphylococcus aureus also resistant to mupirocin.

An epidemic methicillin-resistant Staphlococcus aureus (EMRSA-3) appeared in a District hospital in June 1989 as part of a regional outbreak. The dynamics of the outbreak were complex and involved patient transfer between hospitals and wards. Control measures followed UK guidelines and included the use of nasal mupirocin. During these efforts a mupirocin-resistant MRSA [MuMRSA: mupirocin minimum inhibitor concentration (MIC) > 256 mg/L] emerged, probably in a patient who had been given eight mupirocin courses over nine months. The MuMRSA had a narrower phage-typing pattern than EMRSA-3, but was indistinguishable by pulsed-field gel electrophoresis of SmaI chromosomal restriction enzyme digests and its susceptibility pattern to other antibiotics. The results of in vitro curing and gene probing indicated that mupirocin resistance was encoded on a 48 Md plasmid. MuMRSA spread occurred in 12 patients and 11 staff. The affected patients were nursed on the same ward. The strain was eradicated from patients with oral ciprofloxacin and rifampicin, triclosan skin treatment and nasal fusidic acid and bacitracin cream. The control of the outbreak had significant medical, social and financial implications. Fortunately, there were alternative topical agents to mupirocin, an agent which has played such a key role in MRSA eradication in recent years.

A relapse of paratyphoid fever after treatment with ciprofloxacin in a child with congenital biliary atresia.

This report describes a relapse of Salmonella paratyphi B infection in a child with biliary atresia, following 2 weeks of treatment with ciprofloxacin. The recrudescence was complicated by the development of osteomyelitis and was treated with chloramphenicol, trimethoprim, ceftriaxone and ampicillin in succession.

Differential effect of clozapine on weight: a controlled study.

OBJECTIVE: This study examined whether clozapine induces more weight gain than haloperidol and whether weight gain is related to clinical improvement. METHOD: The weight and symptoms of 39 outpatients with schizophrenia who were randomly assigned to double-blind treatment with either clozapine or haloperidol were assessed. The weight and symptoms of 33 of the patients who chose to take clozapine during a 1-year follow-up after the study ended were also assessed. RESULTS: The patients treated with clozapine gained significantly more weight over baseline (7%) than the haloperidol-treated patients (1%). Weight gain was not significantly correlated with improvements in either positive or negative symptoms. Fifty-eight percent of the patients followed for 1 year gained at least 10% over their baseline weight. CONCLUSIONS: Weight gain is an important side effect of clozapine and is unrelated to the drug's differential antipsychotic efficacy.

Effects of clozapine on positive and negative symptoms in outpatients with schizophrenia.

OBJECTIVE: Clozapine is an atypical neuroleptic with superior efficacy in severely ill, treatment-resistant inpatients with schizophrenia. To determine if clozapine's differential efficacy generalizes to less ill, outpatients populations, the authors examined the effects of clozapine on positive and negative symptoms in outpatients with schizophrenia. METHOD: Outpatients with schizophrenia who had histories of partial response to conventional neuroleptics and who had not responded to a prospective 6-week trial of fluphenazine participated in a 10-week, double-blind, parallel-groups comparison of clozapine and haloperidol. Thirteen men and six women were given clozapine, and 15 men and five women were given haloperidol. Clinical response rates were determined and effects on primary versus secondary negative symptoms were addressed. Doses of clozapine and haloperidol at the end of the 10-week trial were 410.5 mg/day (SD = 45.8) and 24.8 mg/day (SD = 5.5), respectively. RESULTS: Clozapine was superior to haloperidol for treating positive symptoms. In addition, eight of the patients given clozapine and only one of the patients given haloperidol fulfilled clinical responder criteria. Clozapine was also superior to haloperidol for treating negative symptoms, although these effects were relatively minor. Negative symptoms were significantly affected in the subgroup of patients with nondeficit schizophrenia but not in the subgroup with deficit schizophrenia. Overall, clozapine was well tolerated. CONCLUSIONS: Clozapine has superior efficacy for treating positive symptoms in partially responsive outpatients with chronic schizophrenia, suggesting that it has utility for a broad spectrum of patients with schizophrenia beyond the most severely ill.

Clozapine treatment of outpatients with schizophrenia: outcome and long-term response patterns.

OBJECTIVE: The purpose of the study was to examine the effects of clozapine in treating moderately ill schizophrenic outpatients and to determine the length of medication trial needed to identify responders and nonresponders. METHODS: Rates of clinical responses, relapses and hospitalizations, and levels of symptomatology and functioning were assessed for 30 chronic schizophrenic outpatients who received clozapine for one year. For some patients, data on relapse and hospitalization during treatment were compared with data from the year before treatment. RESULTS: Eighteen of the 30 patients met criteria for sustained response; 17 of the responders were identified within the first four months of treatment. Patients experienced significantly fewer relapses and hospitalizations during treatment than in the previous year. Improvement in positive symptoms, general symptomatology, and levels of functioning reached a plateau during the first six months of treatment and remained at that level during the second six months. Negative symptoms and quality of life showed nonsignificant improvements at 12 months. CONCLUSIONS: Results support the use of clozapine in treating chronic, residually symptomatic schizophrenic outpatients. A four-month clozapine trial may be adequate to detect clinical responders in this population.