Assessment of the neutralizing antibody response in Omicron breakthrough cases in healthcare workers who received the homologous booster of Moderna mRNA-1273

Vaccines against SARS-CoV-2 were developed during the pandemic including the BNT162b2 and the mRNA-1273. We evaluated the levels of binding antibodies against the receptor binding domain and the levels of NAbs in individuals who developed a breakthrough infection after having received three doses of mRNA-1273. A total of 51 participants were included. The breakthrough group was compared to a 1:1 matched-control group. Among the 51 individuals, 18 (35%) developed a breakthrough infection. The GMT of NAbs against the BA.1 in the BK population was 278.1 (95%CI: 168.1-324.1). This titer was significantly lower compared to the matched-control group when considering all data (GMT = 477.4; 95%CI: 316.2-541.0; p = 0.0057). Results were similar for the BA.5 (GMT = 152.0 (95%CI: 76.9-172.9) for breakthrough and 262.0 (95%CI: 171.3-301.8) for control (p = 0.0043)). Our study found that individuals receiving the mRNA-1273 booster and who developed a breakthrough infection presented lower levels of binding antibodies and NAbs before the infection as compared to a matched-control group.

Added value of a connected glucose meter for glycorrhachia assessment

Objectives

The aim of this study was to demonstrate the performance and added value of rapid glucose determination in cerebrospinal fluid using a connected glucometer.

Design and Methods

Intra-assay and inter-assay accuracies were calculated using residual clinical samples. Accuracies were measured by comparing the results obtained with the glucometer to those from the central laboratory on a large routine chemistry platform.

Results

The intra-assay coefficients of variation were between 6.1% and 6.2% for low values (18 mg/dL) and between 5.6% and 6.8% for high values (58 mg/dL). The inter-assay coefficients of variation were between 9.4% and 16.3% for the low values (18 mg/dL) and between 5.7% and 8.7% for the high values (pool; ±75 mg/dL). The regression equation by comparison to the central laboratory was y = 4.08 + 0.82 x, with a coefficient of determination (r2) of 0.95.

Conclusions

The measurement of glycorrhachia with a connected glucometer before the analysis in the central laboratory allows a rapid orientation in the deferential diagnosis of a meningitis of viral vs bacterial origin. The response time is fast (6 s) and requires only a small amount of fluid (1.2 μL), which is important in infants, especially since lumbar puncture is an integral part of the investigation of the origin of a fever in this population.

Clinical evaluation of a dermatophyte RT-PCR assay and its impact on the turn-around-time: A prospective study

Onychomycosis is an important public health problem whose prevalence continues to grow and impact public health at several levels. Nevertheless, today the main diagnostic methods used in routine practice have many drawbacks. The aim of this study was to evaluate, for the first time, the clinical performance of a new multiplex polymerase chain reaction (PCR) (Novaplex®) in the identification of the causative agent on nail samples, and its impact on the turnaround time, compared to our traditional laboratory methods. From June 2022 to December 2022, all nail samples sent to our laboratory for suspected onychomycosis were included in this prospective study. We collected for each sample the results obtained with the Novaplex® PCR method and with the traditional direct microscopy examination and culture. Each discordant result was checked using a third method, which is another PCR method (DermaGenius® kit) as a resolver. For culture-positive samples, a turnaround time was calculated and compared to the one obtained with the Novaplex® method. A total of 131 samples were included. Among them, 5 were positive (3.8%) on direct microscopy, 33 were positive (25.2%) after culture, and 98 were negative (74.8%). All positive (n = 33) and negative (n = 69) cultures were also positive/negative with the Novaplex® PCR. Twenty-nine samples were positive with the Novaplex® method but negative with culture (discordant results). The percentage agreement between the culture and the Novaplex® methods was 77.9% (102 out of 131). While tested with the resolver (DermaGenius® PCR), 28 out of 29 discordant results were similarly found positive. The percentage agreement between the two PCR methods (Novaplex® and DermaGenius®) was 96.6%. The Novaplex® PCR method evaluated proved to be very reliable and allowed the direct identification of 62 out of 131 positive samples (47.3%) with the following distribution: 79.0% of Trichophyton rubrum complex, 11.3% of Trichophyton mentagrophytes complex, 6.5% of both Trichophyton rubrum complex and Trichophyton mentagrophytes complex, and 3.2% of Candida albicans. The median time [± 95% CI] for positive culture (between incubation and validation of the final identification) was 15 [12-23] days, while the turnaround time for the Novaplex® method adapted to our clinical laboratory routine is ≤7 days. Laboratory confirmation of onychomycosis is crucial and should always be obtained before starting treatment. The evaluated PCR method offered a rapid, reliable, robust, and inexpensive method of identification of the causative agent compared to traditional methods.

Nursery outbreak caused by enteroaggregative Escherichia coli serogroup O111:H21

This study describes, for the first time, the occurrence of an epidemic of enteroaggregative Escherichia coli (EAEC) O111:H21 in a Belgian nursery and describes a practical approach concerning its management. Few data exist in the literature on this type of outbreak. Clinical and microbiological investigations were needed to find a link between the cases and identify the causative agent. The microbiological procedure followed was first based on conventional analyses: isolation using selective cultures, identification by MALDI-TOF MS, antibiogram, determination of the serogroup by agglutination, then whole genome sequencing. A total of 7/21 children were infected with this pathogen. Four cases could be confirmed by a molecular technique, wgMLST, as belonging to the same bacterial clone. The action plan put in place focused on symptomatic case eviction, strict general hygiene precaution as well as specific cleaning and disinfection measures. The epidemic did last only a few days. It appears important, in the context of an epidemic, that clinical laboratories standardize their practice by equipping themselves with molecular techniques such as a multiplex which does not focus only on the serotype O157:H7 and which make it possible to distinguish the different pathotypes of E. coli by targeting several virulence genes (stx, aggR…). However, cost/effectiveness studies are awaited to confirm the interest of a systematic search by molecular method for the pathogen involved in a suspected outbreak occurring in a nursery.

Organisation and quality monitoring for point-of-care testing (POCT) in Belgium: proposal for an expansion of the legal framework for POCT into primary health care

BACKGROUND

There is a trend towards decentralisation of laboratory tests by means of Point-of-Care testing (POCT). Within hospitals, Belgian law requires a POCT policy, coordinated by the clinical laboratory. There is however no legal framework for POCT performed outside the hospital: no reimbursement, no compulsory quality monitoring and no limits nor control on the prices charged to the patient. Uncontrolled use of POCT can have negative consequences for individual and public health.

PROPOSAL

We propose that POCT outside hospitals would only be reimbursed for tests carried out within a legal framework, requiring evidence-based testing and collaboration with a clinical laboratory, because clinical laboratories have procedures for test validation and quality monitoring, are equipped for electronic data transfer, are familiar with logistical processes, can provide support when technical issues arise and can organise and certify training. Under these conditions the government investment will be offset by health benefits, e.g. fall in antibiotic consumption with POCT for CRP in primary care, quick response to SARS-CoV2-positive cases in COVID-19 triage centres.

PRIORITIES

1° extension of the Belgian decree on certification of clinical laboratories to decentralised tests in primary care; 2° introduction of a separate reimbursement category for POCT; 3° introduction of reimbursement for a limited number of specified POCT; 4° setup of a Multidisciplinary POCT Advisory Council, the purpose of which is to draw up a model for reimbursement of POCT, to select tests eligible for reimbursement and to make proposals to the National Institute for Health and Disability Insurance (RIZIV/INAMI).

Six-month interim analysis of ongoing immunogenicity surveillance of the mRNA-1273 vaccine in healthcare workers: A third dose is expected

Objectives

Scarce data are currently available on the kinetics of antibodies after vaccination with mRNA vaccines as a whole and, with mRNA-1273, in particular. We report here an ad-interim analysis of data obtained after a 6-month follow-up in a cohort of healthcare workers (HCWs) who received the mRNA-1273 vaccine. These new data provide more insight into whether and in whom a 3rd dose could be necessary.

Methods

Our study compared the anti-S antibody kinetics at 2 weeks (T1), 3 months (T3) and 6 months (T4) after the first injection, and 2 weeks after the second injection (T2). The 201 participating HCWs were stratified according to their initial serological status. The vaccine effectiveness was also assessed through a medical questionnaire.

Results

We report here a marked and statistically significant antibody decrease (P < 0.05) between T3 and T4, especially in naïve vaccinees. The analysis of potential confounding factors or known risk factors for severe COVID-19 disease did not reveal any influence on the drop observed. Six-month after vaccination, only one, symptomatic, infection was reported in our cohort.

Conclusions

In a supply-limited environment, our results plead for reserving the 3rd dose scheme, in the upcoming months, to seronegative individuals prior to vaccination, especially when the serological status is easily accessible.

The challenge of screening SARS-CoV-2 variants of concern with RT-qPCR: One variant can hide another

INTRODUCTION

Following the emergence of SARS-CoV-2 variants of concern (VOCs) worldwide, it is important to monitor local epidemiology to better understand the occurrence of clusters, reinfections, or infection after vaccination. Detecting mutations by specific RT-qPCR is a rapid and affordable alternative to sequencing. However, care must be taken to ensure that the techniques used are up-to-date and adapted to the variants circulating in the studied population.

MATERIAL AND METHODS

All samples tested positive for SARS-CoV-2 were screened for detection of mutations of the spike protein using the Novaplex™ SARS-CoV-2 Variants I Assay from week 11 of 2021. Target sought were deletion H69/V70 and mutations N501Y and E484 K. From week 18 we used in addition the new Novaplex™ SARS-CoV-2 Variants II Assay for samples with no targets found with the Variants I assay or with the mutation E484 K alone, in order to screen the mutations L452R, K417 N/T and W152C.

RESULTS

Between weeks 11 and 25, 2239 positive samples out of 54,317 were tested with the Variants I Assay. Between weeks 18 and 25, 94 samples met the criteria for being tested with the Variants II Assay. Of these, 47 had the L452R mutation without the W152C mutation, typical in the B.1.617 variant. At week 25, this profile was found in 45.5 % of the samples and was the most frequent.

CONCLUSION

According to our observations, variant B.1.617 has become predominant in our institution and most probably in our region. In the absence of the use of the Variants II Assay, they would have been considered wild.

Efficacy comparison of three rapid antigen tests for SARS-CoV-2 and how viral load impact their performance

More and more rapid antigen tests for the diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) appear in the market with varying performance. The sensitivity of these tests heavily depends on the viral load, extrapolated by the threshold cycle (Ct). It is therefore essential to verify their performance before their inclusion in routine. The Coronavirus Ag Rapid Test Cassette Bio-Rad, the GSD NovaGen SARS-CoV-2 (COVID-19) Antigen Rapid Test, and the Aegle Coronavirus Ag Rapid Test Cassette were evaluated on 199 samples: 150 fresh samples from the routine and positive in quantitative reverse-transcription polymerase chain reaction (RT-qPCR), nine fresh samples negative in RT-qPCR, and 40 frozen samples, taken before the discovery of SARS-CoV-2 but positive for other respiratory viruses. Positive RT-qPCR samples were categorized according to their Ct: Ct < 20 (18.7%), ≥ 20-< 25 (27.3%), ≥ 25-< 30 (18.7%), ≥ 30-35 (17.3%), and > 35 (18.0%). Sensitivities (95% confidence interval) for Ct below 25 were 95.7% (92.4-98.9), 97.1% (94.4-99.8), and 97.1% (94.4-99.8) for GSD NovaGen, Bio-Rad, and Aegle, respectively but drastically dropped when Ct exceeded 27. Among samples with previously diagnosed viruses, seven false-positive results were found with GSD NovaGen only (specificity 85.7%). Equivalent, high sensitivities were observed with the highest viral load samples. The GSD NovaGen assay showed less specificity. Although the three kits tested in this study are inadequate for routine testing in a high throughput laboratory, they can help to quickly identify the most infectious patients and screen their close contacts in an environment where molecular tests are not readily available.

Diagnosis of respiratory syncytial virus and influenza A and B with cobas® Liat® from nasopharyngeal aspirations in pediatrics

The cobas® Liat® Influenza A/B and respiratory syncytial virus assay was tested on nasopharyngeal aspirates. The resolution of invalid samples was performed using a preanalytical step. cobas® Liat® can be used on nasopharyngeal aspirates with a preanalytical processing step, with a slightly diminished performances in detecting respiratory syncytial virus but not for influenza.

Development and implementation of a RT-qPCR extraction-free protocol for the detection of SARS-CoV-2 and impact on the turn-around-time

The occurrence of the COVID-19 second-wave outbreak in Europe has pushed laboratories performing molecular SARS-CoV-2 tests to increase their throughput and decrease the result rendering time. In this evaluation, we tested for the first time a new, extraction-free, protocol with the Allplex SARS-CoV-2 Assay RT-qPCR kit on a Nimbus platform. Ninety-one samples, of which 71 previously tested positive with RT-qPCR with extraction were immediately analyzed without extraction, using only a dilution and thermal shock protocol. The positive and negative percentage agreements were respectively 97.2% (95% confidence interval [CI]: 0.90-0.99) and 95.0% (95% CI: 0.76-0.99). The two false negatives observed were very weakly positive with the comparison method. Moderate variations in Ct of the targeted genes were observed (median ± 95% CI): E gene, +2.49 ± 0.44; N gene, +0.98 ± 0.54; RdRP/S genes, +2.64 ± 0.48. On the other hand, the number of tests performed within 24 h raised from 86.4% to 97.8%, the turn-around time decreased from 19:18 to 09:03 (p < .0001), and the number of tests that can be performed per day doubled since this technique was introduced routinely in our laboratory.

Analytical and clinical validation of an ELISA for specific SARS-CoV-2 IgG, IgA, and IgM antibodies

The development of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) serological tests is massive. The external validation of their performance is needed before use in clinical routine practice. Our study aims at assessing the analytical and clinical performance of two enzyme‐linked immunosorbent assay tests detecting antibodies directed against the virus nucleocapsid protein: The NovaLisa SARS‐CoV‐2 immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) test (NovaTec) allowing a separate detection of each antibody and the Platelia SARS‐CoV‐2 Total Ab test (Bio‐Rad) detecting total antibodies (IgM, IgA, and IgG). Two‐hundred and eight coronavirus disease 2019 samples from 48 quantitative reverse transcription‐polymerase chain reaction (RT‐qPCR) confirmed patients were used to perform the sensitivity analysis. Non‐SARS‐CoV‐2 sera (n = 79) with a potential cross‐reaction to SARS‐CoV‐2 immunoassays were included in the specificity analysis. In addition, using receiver operator characteristic curves, adapted cut‐off for improvement of the performances were proposed. The kinetics of these antibodies was also assessed over 8 weeks. Two weeks after the RT‐qPCR positive detection, the NovaLisa test shows a sensitivity and specificity of 94.9% (95% confidence interval [CI]: 83.1%‐98.6%) and 96.2% (95% CI: 89.4%‐98.7%) for IgG, of 89.7% (95% CI: 76.4%‐95.9%) and 98.7% (95% CI: 93.2%‐98.8%) for IgA, and of 48.7% (95% CI: 33.9%‐63.8%) and 98.7% (95% CI: 93.2%‐99.8%) for IgM. With the Platelia system, the specificity and sensitivity were 97.4% (95% CI: 92.1%‐99.7%) and 94.9% (95% CI: 87.7%‐98.0%) for total antibodies using the adapted cut‐offs. The NovaLisa and the Platelia tests have satisfactory analytical performances. The clinical performances are excellent for IgG, IgA, and total antibodies especially if the cut‐off is optimized.

The sensitivity and the specificity of the NovaLisa (for immunoglobulin G [IgG] and immunoglobulin A [IgA]) and the Platelia were excellent.

Cut‐off optimizations improve the clinical performances of both assays.

Over a period of 8 weeks, IgM and IgA gradually disappeared while IgG remain persistent.

Implementation of rapid SARS-CoV-2 antigenic testing in a laboratory without access to molecular methods: Experiences of a general hospital

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The COVID-19 Ag Respi-Strip assay is a new immunochromatographic diagnostic tool for antigenic diagnosis of SARS-CoV-2.

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This test did not reduce significantly the number of samples outsourced for COVID-19 confirmation.

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The sensitivity of this rapid test is poor and improvements are needed to enhance its performances.

Background

The COVID-19 Ag (Antigen) Respi-Strip assay is a new immunochromatographic diagnostic tool recently available for antigenic diagnosis of SARS-CoV-2. The proposed sensitivity is not higher than 60 %, but its high specificity allows both quick decisions for the management of patients and confirmation by molecular diagnosis for only negative tests. However, from the first tests performed, we suspected that the sensitivity observed with routine use was much lower than that announced by the manufacturer.

Materials and methods

Over a period of one month, we compared the negative results obtained with the COVID-19 Ag Respi-Strip kit with those obtained from qRT-PCR performed in a laboratory qualified for the molecular diagnosis of SARS-CoV-2. All samples tested were naso-pharyngeal smears from UTM-RT medium.

Results

Of 774 patients tested, 714 negative samples were sent for confirmation, and 159 were found to be positive by qRT-PCR. The median positive percentage agreement was 23.9 % (95 % CI: 14.2 %–38.2 %). The Cohen’s kappa score was 0.35.

Conclusion

Using this immunochromatographic assay as a triage test did not significantly reduce the number of samples outsourced for COVID-19 confirmation by qRT-PCR. In addition, even if the turn-around time is short, the assay is completely manual, which is not suitable for large volumes of routine samples. The sensitivity of this rapid test is poor, and improvements are needed to enhance its performance.

Validation of a chemiluminescent assay for specific SARS-CoV-2 antibody

Objectives

Faced with the COVID-19 pandemic and its impact on the availability and quality of both therapeutic and diagnostic methods, the Belgian authorities have decided to launch a procedure for additional evaluation of the performance of serological tests offered for sale on the national territory. This has been proposed with a double aim: (1) an in-depth verification of the analytical and clinical performances presented by the manufacturer and (2) an economy of scale in terms of centralized validation for all the laboratories using the tests subject to evaluation.

Methods

A retrospective validation study was conducted including the serum of 125 patients in order to determine the analytical and clinical performances of the LIAISON®SARS-CoV-2 from DiaSorin® detecting anti-SARS-CoV-2 IgG and to compare its clinical performance with the enzyme-linked immunosorbent assay (ELISA) test from Euroimmun®, one of the first commercially available tests allowing the detection of anti-SARS-CoV-2 IgA and IgG.

Results

The performances of the LIAISON®SARS-CoV-2 satisfied all the acceptance criteria and provided “real world” analytical and clinical performances very close to the ones reported by the manufacturer in its insert kit. Comparison between the LIAISON®SARS-CoV-2 and the ELISA method did not reveal any difference between the two techniques in terms of sensitivities and specificities regarding the determination of the IgG.

Conclusions

This study reports the validation of the LIAISON®SARS-CoV-2 allowing to detect IgG antibodies specifically directed against SARS-CoV-2. The analytical and clinical performances are excellent, and the automation of the test offers important rates, ideal for absorbing an extension of testing.

Improving NSAIDs Prescription in Emergency Services Unit by a Point-of-Care-Based Renal Function Evaluation

BACKGROUND

Patients evaluated in our emergency department (ED) often receive nonsteroidal anti-inflammatory drugs (NSAIDs) without any determination of their renal function, despite the known nephrotoxicity of NSAIDs. Guidelines recommend NSAID avoidance in patients with estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m², and long-lasting therapy is not recommended in people with chronic kidney disease.

OBJECTIVE

We aimed to highlight the influence of a rapid measurement of the eGFR on NSAID prescriptions in patients at risk of impaired renal function using a point-of-care (POC) device. Our goal was to prevent the potential nephrotoxicity of NSAIDs by allowing the physicians to modify their treatments after eGFR determination, while avoiding a standard blood test for patients that would extend the duration of stay in the ED.

METHODS

We included 192 patients evaluated in the ED for minor trauma or injury, with an indication of treatment with NSAIDs and no known contraindication to NSAIDs. Emergency physicians were asked to register their intention to actually prescribe NSAIDs based on their clinical gestalt with specific regard to kidney function. Immediately after, the creatinine level was measured in capillary blood and eGFR was calculated using the POC device (StatSensor Creatinine; Nova Biomedical, Waltham, MA). Our physicians avoided NSAID prescriptions when eGFR was < 30 mL/min/1.73 m², and prescribed a shorter NSAID regimen therapy in patient with eGFR < 45 mL/min/1.73 m², with a reminder to assure hydration. The decision based on eGFR was compared with original clinician intention.

RESULTS

The clinicians intended to treat 164 patients with NSAIDs (group 1) and defer NSAIDs in 28 patients (group 2). In the first group, eGFR results supported no change in intended NSAID use in 144 patients, highlighted the need for a short regimen in 17 patients, and indicated contraindication to NSAIDs in 3 patients. In group 2, eGFR determination allowed prescription of NSAIDs in 21 patients, allowed utilization of NSAIDs with a short course in 5 patients, and supported the clinician decision to avoid NSAIDs in 2 patients.

CONCLUSIONS

POC measurement of creatinine with eGFR estimation changed the prescription of NSAIDs in almost 25% of patients with previously unknown renal function.

Vitek 2 ANC card versus BBL Crystal Anaerobe and RapID ANA II for identification of clinical anaerobic bacteria

The Vitek 2 Anaerobe and Corynebacterium Identification Card (ANC) was recently evaluated in a multicentre study. In the present work, this system was compared with the BBL Crystal Anaerobe and RapID ANA II panels. These kits were tested using 196 strains of anaerobes that had been previously identified by gas-liquid chromatography. Identification to the species or to the genus level was 75.0%, 81.1% and 70.9% for Crystal, RapID and Vitek, respectively. Vitek ANC failed to provide any identification in 20.4% of the strains, but it had fewer misidentifications than RapID. The confidence factors provided on the results report of each kit were not always correlated with a lower risk of major errors, with the exception of Vitek 2 in which a confidence factor higher than 0.86 excluded the risk of misidentification in more than 87% of isolates. The lower rate of identification by the Vitek and Crystal panels is mostly due the lower ability of these systems to identify the Clostridia. Overall, the three panels are comparable but need improvement to a better accuracy.

A 62-month retrospective epidemiological survey of anaerobic bacteraemia in a university hospital

The incidence of anaerobic bacteraemia was studied retrospectively over 62 months at Mont-Godinne University Hospital, Yvoir, Belgium. The distribution of organisms, clinical presentations, choice of antimicrobial therapy and clinical outcome were analysed. The proportion of positive blood cultures yielding obligate anaerobes was 3.3%. The overall incidence of clinically significant anaerobic bacteraemia was 0.51 cases/1,000 patient admissions (0.61 cases/10,000 hospital-days), but was significantly higher in patients with active haematological malignancies than in other groups (5.97/10,000 vs. 0.33/10,000 hospital-days; p < 0.05). The Bacteroides fragilis group accounted for 61% of isolates, followed by Clostridium spp. (12.2%), Peptostreptococcus spp. and Leptotrichia spp. (7.3% each) and Fusobacterium spp. (4.8%). The most common risk-factors were gastrointestinal surgery (49%) and active haematological malignancies with chemotherapy and/or bone marrow graft (47%). One or more co-morbidities were present in 30 (77%) of 39 patients. The lower gastrointestinal tract (41%) and the oropharynx (23%) were the two most frequent presumed or proven sources for bacteraemia, with the origin remaining unknown in eight (20.5%) cases. The overall mortality rate (evaluated 7 days after the occurrence of bacteraemia) was 13%. Fatal outcome correlated with the severity of underlying diseases and the immunosuppressed status of the patients rather than with the causative pathogen or the effectiveness of antimicrobial therapy. Likewise, there was no difference in the mortality rate between patients with monomicrobial and polymicrobial bacteraemia. Overall, the data re-emphasise the importance of anaerobic bacteraemia, especially in patients with haematological malignancies.

Lipopolysaccharide-binding protein serum levels in patients with severe sepsis due to gram-positive and fungal infections

Lipopolysaccharide-binding protein (LBP) is increased in patients with severe gram-negative infections, but LBP serum levels have not been reported for in patients with gram-positive and fungal infections. LBP serum levels were determined in patients with severe sepsis secondary to gram-positive or fungal infections and were compared with LBP serum levels obtained from patients with gram-negative mixed infections and from healthy volunteers. Thirty-seven episodes of severe sepsis were analyzed among 24 patients. LBP serum levels were significantly increased in patients with severe sepsis (46.4+/-28.3 microg/mL), compared with that of healthy volunteers (5.7+/-1.9 microg/mL; P<.0001). On the other hand, LBP serum levels obtained from patients with gram-negative infections (40.80+/-34.79 microg/mL) did not differ from those obtained from patients with gram-positive (35.55+/-23.95 microg/mL) or fungal (39.90+/-22.19 microg/mL) infections. These data suggest that LBP is an aspecific marker of sepsis, and the response was not clearly correlated with severity. Furthermore, in patients with multiple episodes of sepsis, LBP response seems to be of lesser magnitude after each subsequent episode of severe sepsis.