Evidence of Reduced Virulence and Increased Colonization Among Pneumococcal Isolates of Serotype 3 Clade II Lineage in Mice.

Recent phylogenetic profiling of pneumococcal serotype 3 (Pn3) isolates revealed a dynamic interplay among major lineages with the emergence and global spread of a variant termed clade II. The cause of Pn3 clade II dissemination along with epidemiological and clinical ramifications are currently unknown. Here, we sought to explore biological characteristics of dominant Pn3 clades in a mouse model of pneumococcal invasive disease and carriage. Carriage and virulence potential were strain dependent with marked differences among clades. We found that clinical isolates from Pn3 clade II are less virulent and less invasive in mice compared to clade I isolates. We also observed that clade II isolates are carried for longer and at higher bacterial densities in mice compared to clade I isolates. Taken together, our data suggest that the epidemiological success of Pn3 clade II could be related to alterations in the pathogen's ability to cause invasive disease and to establish a robust carriage episode.

Field Study and Correlative Studies of Factor IX Variant FIX-R338L in Participants Treated with Fidanacogene Elaparvovec.

BACKGROUND: Fidanacogene elaparvovec, an adeno-associated virus-based gene therapy vector expressing the high-activity factor IX (FIX) variant FIX-R338L, is in development for hemophilia B. One-stage clotting (OS) assays and chromogenic substrate (CS) assays are commonly used to measure FIX-R338L variant activity. Data from ongoing trials suggest FIX activity varies between different OS and CS assays. MATERIAL AND METHODS: To better understand FIX-R338L activity in clinical samples, an international multisite field study was conducted across a central laboratory and 18 local laboratories, using standard protocols, reagents, and instrumentation, with individual participant samples from a phase 1/2a study of fidanacogene elaparvovec. RESULTS: Unlike the wild-type FIX control, FIX-R338L activity was higher with the OS silica-based assay versus OS ellagic acid-based and CS assays. Variation in FIX activity was greater at the lowest activity levels. Activated FIX (FIXa) in plasma could result in higher OS assay activity or increased thrombin generation, which could overestimate FIX activity. However, FIXa was not detected in the participant samples, indicating that it was not contributing to the OS assay differences. Since individuals on gene therapy may receive exogenous replacement FIX products, replacement products were spiked into patient plasma samples to target a therapeutic concentration. Exogenous FIX was additive to endogenous FIX-R338L, with no interference from FIX-R338L. CONCLUSION: These results demonstrate FIX-R338L activity can be measured with OS and CS assays in clinical laboratories and provide insight into assay variability when measuring FIX with endogenously produced FIX-R338L. The findings may help establish best practices for measuring FIX-R338L activity (Clinicaltrials.gov identifier: NCT02484092).

Development and validation of a 6-plex Luminex-based assay for measuring human serum antibodies to group B streptococcus capsular polysaccharides.

Six serotypes (Ia, Ib, II, III, IV, and V) cause nearly all group B streptococcal (GBS) disease globally. Capsular polysaccharide (CPS) conjugate vaccines aim to prevent GBS disease, however, licensure of a vaccine would depend on a standardized serological assay for measuring anti-CPS IgG responses. A multiplex direct Luminex-based immunoassay (dLIA) has been developed to simultaneously measure the concentration of serum IgG specific for the six prevalent GBS CPS serotypes. Assay validation was performed using serum samples obtained from human subjects vaccinated with an investigational 6-valent GBS CPS conjugate vaccine. Results for the assay are expressed as IgG concentrations (µg/mL) using a human serum reference standard composed of pooled sera from vaccinated subjects. The lower limits of quantitation (LLOQ) for all serotypes covered in the 6-plex GBS IgG dLIA fell within the range of 0.002-0.022 µg/mL IgG. Taken together, the 6-plex GBS IgG dLIA platform is specific for the six GBS serotypes included in Pfizer's investigational vaccine, has a wide dilution adjusted assay range, and is precise (<18.5% relative standard deviation) for all serotypes, and, therefore, is suitable for quantitatively measuring vaccine-induced or naturally acquired serotype-specific anti-CPS IgG responses against GBS.

Interlaboratory comparison of a multiplex immunoassay that measures human serum IgG antibodies against six-group B streptococcus polysaccharides.

Measurement of IgG antibodies against group B streptococcus (GBS) capsular polysaccharide (CPS) by use of a standardized and internationally accepted multiplex immunoassay is important for the evaluation of candidate maternal GBS vaccines in order to compare results across studies. A standardized assay is also required if serocorrelates of protection against invasive GBS disease are to be established in infant sera for the six predominant GBS serotypes since it would permit the comparison of results across the six serotypes. We undertook an interlaboratory study across five laboratories that used standardized assay reagents and protocols with a panel of 44 human sera to measure IgG antibodies against GBS CPS serotypes Ia, Ib, II, III, IV, and V. The within-laboratory intermediate precision, which included factors like the lot of coated beads, laboratory analyst, and day, was generally below 20% relative standard deviation (RSD) for all six serotypes, across all five laboratories. The cross-laboratory reproducibility was < 25% RSD for all six serotypes, which demonstrated the consistency of results across the different laboratories. Additionally, anti-CPS IgG concentrations for the 44-member human serum panel were established. The results of this study showed assay robustness and that the resultant anti-CPS IgG concentrations were reproducible across laboratories for the six GBS CPS serotypes when the standardized assay was used.

Evidence of Reduced Virulence and Increased Colonization among Pneumococcal Isolates of Serotype 3 Clade II Lineage in Mice.

Recent phylogenetic profiling of pneumococcal serotype 3 (Pn3) isolates revealed a dynamic interplay among major lineages with the emergence and global spread of a variant termed Clade II. The cause of Pn3 clade II dissemination along with epidemiological and clinical ramifications are currently unknown. Here, we sought to explore biological characteristics of dominant Pn3 clades in a mouse model of pneumococcal invasive disease and carriage. Carriage and virulence potential were strain dependent with marked differences among clades. We found that clinical isolates from Pn3 clade II are less virulent and less invasive in mice compared to clade I isolates. We also observed that clade II isolates are carried for longer and at higher bacterial densities in mice compared to clade I isolates. Taken together, our data suggest that the epidemiological success of Pn3 clade II could be related to alterations in the pathogen's ability to cause invasive disease and to establish a robust carriage episode.

Calibration of a serum reference standard for Group B streptococcal polysaccharide conjugate vaccine development using surface plasmon resonance.

Group B streptococcus (GBS) is a leading cause of neonatal morbidity and mortality worldwide. Development of a maternal vaccine to protect newborns through placentally transferred antibody is considered feasible based on the well-established relationship between anti-GBS capsular polysaccharide (CPS) IgG levels at birth and reduced risk of neonatal invasive GBS. An accurately calibrated serum reference standard that can be used to measure anti-CPS concentrations is critical for estimation of protective antibody levels across serotypes and potential vaccine performance. For this, precise weight-based measurement of anti-CPS IgG in sera is required. Here, we report an improved approach for determining serum anti-CPS IgG levels using surface plasmon resonance with monoclonal antibody standards, coupled with a direct Luminex-based immunoassay. This technique was used to quantify serotype-specific anti-CPS IgG levels in a human serum reference pool derived from subjects immunized with an investigational six-valent GBS glycoconjugate vaccine.

Streptococcus pneumoniae serotype 15B polysaccharide conjugate elicits a cross-functional immune response against serotype 15C but not 15A.

Protection conferred by pneumococcal polysaccharide conjugate vaccines (PCVs) is associated with PCV-induced antibodies against vaccine-covered serotypes that exhibit functional opsonophagocytic activity (OPA). Structural similarity between capsular polysaccharides of closely related serotypes may result in induction of cross-reactive antibodies with or without a cross-functional activity against a serotype not covered by a PCV, with the former providing an additional protective clinical benefit. Serotypes 15B, 15A, and 15C, in the serogroup 15, are among the most prevalent Streptococcus pneumoniae serotypes associated with invasive pneumococcal disease following the implementation of a 13-valent PCV; in addition, 15B contributes significantly to acute otitis media. Serological discrimination between closely related serotypes such as 15B and 15C is complicated; here, we implemented an algorithm to quickly differentiate 15B from its closely related serotypes 15C and 15A directly from whole-genome sequencing data. In addition, molecular dynamics simulations of serotypes 15A, 15B, and 15C polysaccharides demonstrated that while 15B and 15C polysaccharides assume rigid branched conformation, 15A polysaccharide assumes a flexible linear conformation. A serotype 15B conjugate, included in a 20-valent PCV (PCV20), induced cross-functional OPA serum antibody responses against the structurally similar serotype 15C but not against serotype 15A, both not included in PCV20. In PCV20-vaccinated adults (18-49 years), robust OPA antibody titers were detected against both serotypes 15B (the geometric mean titer [GMT] of 19,334) and 15C (GMTs of 1692 and 2747 for strains PFE344340 and PFE1160, respectively), but were negligible against serotype 15A (GMTs of 10 and 30 for strains PFE593551 and PFE647449, respectively). Cross-functional 15B/C responses were also confirmed using sera from a larger group of older adults (60-64 years).

Development and clinical validation of an automated cell cytotoxicity neutralization assay for detecting Clostridioides difficile toxins in clinically relevant stools samples.

OBJECTIVES: To improve the diagnostic accuracy of Clostridioides difficile infection, current U.S. and E.U. guidelines recommend multistep testing that detects the presence of C. difficile and toxin in clinically relevant stool samples to confirm active disease. An accepted gold standard to detect C. difficile toxins is the cell cytotoxicity neutralization assay (CCNA). Although highly sensitive, the traditional CCNA has limitations. One such limitation is the subjective interpretation of an analyst to recognize cytopathic effects in cultured cells exposed to a fecal sample containing toxin. To overcome this limitation, an automated CCNA was developed that replaces most human pipetting steps with robotics and incorporates CellTiterGlo® for a semi-quantitative, non-subjective measure of cell viability instead of microscopy. METHODS: To determine sample positivity and control for non-specific cytopathic effects, two thresholds were defined and validated by evaluating the sample with/without antitoxin antisera (sample-antitoxin/sample + antitoxin): 1) a >70% cell viability threshold was validated with samples containing anti-toxin, and 2) a >1.2-fold difference cut-off where sample results above the cut-off are considered positive. RESULTS: Assay validation demonstrated excellent accuracy, precision, and sample linearity with an LOD of 126.9 pg/mL toxin-B in stool. The positivity cut-offs were clinically validated by comparing 322 diarrheal stool sample results with those run in a predicate, microscopic readout-based CCNA. The automated CCNA demonstrated 96% sensitivity and 100% specificity compared with the predicate CCNA. CONCLUSIONS: Overall, the automated CCNA provides a specific, sensitive, and reproducible tool to support determination of CDI epidemiology or the efficacy of interventions such as vaccines.

Symptomatic treatment (using NSAIDS) versus antibiotics in uncomplicated lower urinary tract infection: a meta-analysis and systematic review of randomized controlled trials.

BACKGROUND: Current guidelines recommend empiric antibiotics as first-line treatment for uncomplicated UTI. Despite proven benefits in treatment, antibiotic resistance rates remain on the rise. This meta-analysis aims to determine whether non-steroidal anti-inflammatory drugs can serve as an effective and safe option in the treatment of uncomplicated lower UTI among non-pregnant women compared to antibiotics. METHODS: A systematic literature search in PUBMED, CENTRAL, and ACP databases from inception to April 2021 was conducted to identify randomized controlled trials that compare the use of non-steroidal anti-inflammatory drugs versus antibiotics in non-pregnant women ≥18 years old with uncomplicated lower urinary tract infection. Primary outcomes were symptom resolution of UTI by Day 3 or 4 of intervention, and upper UTI complications. Secondary outcomes include persistence of positive urine culture despite treatment and need for another rescue antibiotic. Random and fixed-effects model for dichotomous data using Mantel-Haenszel and Peto odds method were reported at 95% CI followed by sensitivity analysis for substantial heterogeneity. RESULTS: Four RCTs involving 1165 patients were analyzed. The probability of having a symptom resolution by Day 3 or 4 with NSAID use is only less than three-fourths of that with antibiotic treatment (RR: 0.69, 95% CIs [0.55, 0.86], p = 0.0008, I2 = 73%, moderate certainty of evidence). The odds of developing upper UTI complications with use of NSAIDs are 6.49 to 1 for antibiotics (Peto OR: 6.49, 95% CIs [3.02, 13.92], p < 0.00001, I2 = 0%, moderate certainty of evidence). Secondary analysis showed that the NSAID group is 2.77x more likely to have persistence of a positive microbiologic urine culture than the antibiotic group (RR: 2.77, 95% CIs [1.95, 3.94], p < 0.00001, I2 = 36%, moderate certainty of evidence). Treatment with NSAIDs are three times more likely to use a secondary or rescue antibiotic due to persistent or worsening symptoms as compared to antibiotics (RR: 3.16, 95% CIs [2.24, 4.44], p < 0.00001, I2 = 47%, low certainty of evidence). CONCLUSION: Antibiotic treatment was more effective than use of non-steroidal anti-inflammatory drugs for acute uncomplicated lower urinary tract infection with an overall moderate certainty of evidence.

Qualification and Clinical Validation of an Immunodiagnostic Assay for Detecting 11 Additional Streptococcus pneumoniae Serotype-specific Polysaccharides in Human Urine.

BACKGROUND: Identifying Streptococcus pneumoniae serotypes by urinary antigen detection (UAD) assay is the most sensitive way to evaluate the epidemiology of nonbacteremic community-acquired pneumonia (CAP). We first described a UAD assay to detect the S. pneumoniae serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F, covered by the licensed 13-valent S. pneumoniae conjugate vaccine. To assess the substantial remaining pneumococcal disease burden after introduction of several pneumococcal vaccines, a UAD-2 assay was developed to detect 11 additional serotypes (2, 8, 9N, 10A, 11A, 12F, 15B, 17F, 20, 22F, and 33F) in individuals with radiographically confirmed CAP. METHODS: The specificity of the UAD-2 assay was achieved by capturing pneumococcal polysaccharides with serotype-specific monoclonal antibodies, using Luminex technology. Assay qualification was used to assess accuracy, precision, and sample linearity. Serotype positivity was based on cutoffs determined by nonparametric statistical evaluation of urine samples from individuals without pneumococcal disease. The sensitivity and specificity of the positivity cutoffs were assessed in a clinical validation, using urine samples obtained from a large study that measured the proportion of radiographically confirmed CAP caused by S. pneumoniae serotypes in hospitalized US adults. RESULTS: The UAD-2 assay was shown to be specific and reproducible. Clinical validation demonstrated assay sensitivity and specificity of 92.2% and 95.9% against a reference standard of bacteremic pneumonia. In addition, the UAD-2 assay identified a S. pneumoniae serotype in 3.72% of nonbacteremic CAP cases obtained from hospitalized US adults. When combined with bacteremic CAP cases, the proportion of pneumonias with a UAD-2 serotype was 4.33%. CONCLUSIONS: The qualified/clinically validated UAD-2 method has applicability in understanding the epidemiology of nonbacteremic S. pneumoniae CAP and for assessing the efficacy of future pneumococcal conjugate vaccines that are under development.

Criteria to Reevaluate Anti-drug Antibody Assay Cut Point Suitability in the Target Population.

After tier 1 and 2 cut points for anti-drug antibody (ADA) assays are derived during pre-study assay validation in a population, there is a need to verify the continued appropriateness of the previously derived cut points during sample analysis in the same or different populations, per FDA guidance (US HHS, FDA, CDER, CBER, 2019). Proper sample size-dependent criteria with statistical underpinning were derived and presented in this technical note to aid in assessing the appropriateness of tier 1 and tier 2 cut points, respectively.

Evaluation of a Validated Luminex-Based Multiplex Immunoassay for Measuring Immunoglobulin G Antibodies in Serum to Pneumococcal Capsular Polysaccharides.

This article describes the results of a study designed to bridge the World Health Organization (WHO) pneumococcal enzyme-linked immunosorbent assay (ELISA) platform to the validated Luminex-based 13-plex direct immunoassay (dLIA) platform developed by Pfizer, Inc. Both assay platforms quantify serotype-specific serum IgG antibodies (in micrograms per milliliter) against an international reference standard serum. The primary goal of this study was to determine if the dLIA is a suitable replacement for the ELISA to support clinical vaccine studies that include the evaluation of immune responses to serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F. Serum samples were selected from four pivotal 13-valent pneumococcal conjugate vaccine (13vPnC; Prevnar 13) clinical trials on the basis of their serotype-specific IgG concentrations by ELISA. In these studies, subjects were immunized either with 13vPnC or with 7-valent pneumococcal conjugate vaccine (7vPnC; Prevnar). There were 1,528 of 1,574 selected samples with sufficient remaining volume for reanalysis in the dLIA. A comparison of assay results from the dLIA and ELISA platforms showed clear and robust linear quantitative relationships across all 13 serotypes. In addition, lower IgG antibody concentrations in preimmunization samples were measured in the dLIA, thus allowing better differentiation between preimmunization and low-titer postimmunization samples. Overall, the results showed that the established population-level protective threshold IgG concentration, 0.35 µg/ml of serotype-specific serum IgG antibodies, is appropriate for use for data generated using the dLIA platform developed by Pfizer, Inc., for 10 serotypes: serotypes 1, 3, 4, 6A, 7F, 9V, 14, 18C, 19F, and 23F. On the basis of the extensive bridging analyses, however, the use of dLIA cutoff values of 0.23, 0.10, and 0.12 µg/ml is recommended for serotypes 5, 6B, and 19A, respectively. This adjustment will ensure that the consistency of the established population-level protective threshold IgG concentration is maintained when switching from the ELISA to the dLIA platform. The results of this bridging study demonstrate that the 13-plex dLIA platform is a suitable replacement for the WHO reference ELISA platform.IMPORTANCE The pneumococcal enzyme-linked immunosorbent assay (ELISA) measures IgG antibodies in human serum, and it is an important assay that supports licensure of pneumococcal vaccines. The immune correlate of protection, 0.35 µg/ml of IgG antibodies, was determined by the ELISA method. Pfizer has developed a new Luminex-based assay platform to replace the ELISA. These papers describe the important work of (i) validating the Luminex-based assay and (ii) bridging the immune correlate of protection (0.35 µg/ml IgG) to equivalent values reported by the Luminex platform.

Pan-genomic perspective on the evolution of the Staphylococcus aureus USA300 epidemic.

Staphylococcus aureus USA300 represents the dominant community-associated methicillin-resistant S. aureus lineage in the USA, where it is a major cause of skin and soft tissue infections. Previous comparative genomic studies have described the population structure and evolution of USA300 based on geographically restricted isolate collections. Here, we investigated the USA300 population by sequencing genomes of a geographically distributed panel of 191 clinical S. aureus isolates belonging to clonal complex 8 (CC8), derived from the Tigecycline Evaluation and Surveillance Trial program. Isolates were collected at 12 healthcare centres across nine USA states in 2004, 2009 or 2010. Reconstruction of evolutionary relationships revealed that CC8 was dominated by USA300 isolates (154/191, 81 %), which were heterogeneous and demonstrated limited phylogeographic clustering. Analysis of the USA300 core genomes revealed an increase in median pairwise SNP distance from 62 to 98 between 2004 and 2010, with a stable pattern of above average dN/dS ratios. The phylogeny of the USA300 population indicated that early diversification events led to the formation of nested clades, which arose through cumulative acquisition of predominantly non-synonymous SNPs in various coding sequences. The accessory genome of USA300 was largely homogenous and consisted of elements previously associated with this lineage. We observed an emergence of SCCmec negative and ACME negative USA300 isolates amongst more recent samples, and an increase in the prevalence of ϕSa5 prophage. Together, the analysed S. aureus USA300 collection revealed an evolving pan-genome through increased core genome heterogeneity and temporal variation in the frequency of certain accessory elements.

Laparoscopic ventral hernia repair: defining the learning curve.

Between 2004 and June 2011, 181 patients underwent laparoscopic ventral hernia repair. Three main surgeons, all experienced in laparoscopic procedures, performed all the cases. After analyzing the operative time (OT) for 3 main surgeons, within the first 20 cases the overall performance plateaued. Data from 60 patients (50F, 10M), with a mean age of 42.3 years (range, 26 to 88 y) and a mean hernia defect size of 6.5 cm (range, 4 to 18 y), were evaluated. No significant differences were recorded among the 3 surgeons in OT and intraoperative or postoperative complications. But 3 (5%, P<0.03) patients had complications, and the recurrence rate was 6.6% with a mean follow-up of 54 months (range, 42 to 70 mo). One had prolonged postoperative ileus, the second had bowel serosal tear, and the last had port-site incarcerated hernia. Our results showed that the OT of 98.9 minutes (range, 48 to 205 min) stabilized in 12 cases.

A multi-country evaluation of Neisseria meningitidis serogroup B factor H-binding proteins and implications for vaccine coverage in different age groups.

BACKGROUND: Recombinant vaccines containing factor H-binding protein (fHBP) have been developed for the purpose of protection from invasive meningococcal serogroup B disease. Neisseria meningitidis fHBP sequences can be divided into 2 genetically and immunologically distinct subfamilies (A and B); thus, cross protection is conferred within but not between subfamilies. A comprehensive understanding of fHBP epidemiology is required to accurately assess the potential vaccine impact when considering different vaccination implementation strategies. METHODS: Systematically collected invasive meningococcal serogroup B isolates from England, Wales, Northern Ireland, the United States, Norway, France and the Czech Republic were previously characterized for fHBP sequence. This study expanded the evaluation with additional meningococcal serogroup B disease isolates from Spain (n = 346) and Germany (n = 205). This expanded set (n = 1841), collected over a 6-year period (2001 to 2006), was evaluated for fHBP sequence and fHBP subfamily relative to patient age. RESULTS: All 1841 isolates contained fhbp. fHBP sequences from Spain and Germany fell within the previously described subfamilies, with 69% of isolates belonging to subfamily B and 31% to subfamily A; prevalent sequence variants were also similar. Stratification of data by age indicated that disease in infants <1 year of age was caused by a significantly higher proportion of isolates with fHBP subfamily A variants than that seen in adolescents and young adults 11-25 years (47.7% versus 19.5%, P < 0.0001, respectively). CONCLUSIONS: These observations highlight a difference in epidemiology of fHBP subfamilies in different age groups, with fHBP subfamily A strains causing more disease in vulnerable populations, such as infants, than in adolescents.

Single-port access adrenalectomy: our initial experience.

BACKGROUND: After being introduced in 1992, laparoscopic adrenalectomy has been accepted as the gold standard today for benign diseases. The need is now being realized for newer innovations to further reduce the trauma of surgical access. We report our experience and outcome of the first case series of single-port access adrenalectomy by using SILS™ port. METHODS: Between June 2009 and November 2010, 6 patients with adrenal tumors underwent single-port access adrenalectomy via SILS port. The device was placed through a single 3 cm incision. The patients' demographics, adrenal mass characteristics, operative time, conversion rate, intraoperative and postoperative complications, and postoperative pain score were measured. Five patients underwent adrenalectomy by using the retroperitoneal approach and 1 by using the laparoscopic transperitoneal approach. RESULTS: Three men and 3 women with mean age 51 years (range, 37-67) underwent single-incision adrenalectomy. The mean tumor size was 3.3 cm (range, 1.5-6). Three of these cases were Conn's syndrome, and the remaining 3 were incidentaloma. No significant complications or conversions to the conventional procedure were recorded. The mean operative time was 121 minutes (range, 70-165). The mean hospital stay was 2.7 days (range, 2-4). No local recurrences or hormonal relapse have been recorded to the present with a median follow-up of 12 months (range, 3-20). CONCLUSIONS: In our short experience, single-port access adrenalectomy seems to be safe and feasible in improving the advantages of laparoscopic approach, especially in terms of cosmesis, but further randomized controlled trials are needed to evaluate the benefits of this novel approach.

A fully human monoclonal antibody to Staphylococcus aureus iron regulated surface determinant B (IsdB) with functional activity in vitro and in vivo.

A fully human monoclonal antibody (CS-D7, IgG1) specific for the iron regulated surface determinant B (IsdB) of Staphylococcus aureus was isolated from the Cambridge Antibody Technology (CAT) scFv antibody library. As compared to previously described IsdB specific murine monoclonals, CS-D7 has a unique, non-overlapping binding site on IsdB, and exhibits increased in vivo activity. The antibody recognizes a conformational epitope spanning amino acids 50 to 285 and has a binding affinity of 340 (± 75) pM for IsdB. CS-D7 bound to a wide variety of S. aureus strains, but not to an isdB deletion mutant. The antibody mediated opsonophagocytic (OP) killing in vitro and mediated significant protection in vivo. In a murine lethal sepsis model, the antibody conferred protection from death when dosed prior to challenge, but not when dosed after challenge. Importantly, in a central venous catheter (CVC) model in rats, the antibody reduced bacteremia and prevented colonization of indwelling catheters. Protection was observed when rats were dosed with CS-D7 prior to challenge as well as post challenge. IsdB is currently being investigated for clinical efficacy against S. aureus infection, and the activity of this human IsdB specific antibody supplements the growing body of evidence to support targeting this antigen for vaccine development.

Intramuscular injection of parathyroid autografts is a viable option after total parathyroidectomy.

INTRODUCTION: Surgical transplantation of parathyroid gland into muscle is an established technique after total parathyroidectomy for renal hyperparathyroidism. However, no study has examined the role of injecting parathyroid tissue in these patients. We compared the outcome of surgical transplantation of parathyroid glands by implantation ("implant") versus that of intramuscular injection ("inject"). METHODS: Patients who had total parathyroidectomy for tertiary hyperparathyroidism due to chronic renal failure from 2001-2008 are included in this study. For the implant group, a parathyroid gland is divided into 10-12 pieces (each of 2-mm in diameter) before embedding into the deltoid or brachioradialis muscle. Patients in the inject group, each had a finely minced gland injected into the deltoid. Postoperatively, the graft is deemed to be functioning if 1) serum PTH is normal, or 2) serum calcium is normal in the absence of calcium supplements or reduced dosage requirements; these assays are performed at least 1 month after initial surgery. Recurrence is defined by the presence of hyperparathyroidism requiring autograft excision. RESULTS: A total of 66 patients (23 men, 43 women) were included in the study. The implant group comprised 31 patients (mean age 49.9 +/- 14.0), and the inject group had 35 patients (mean age 49.2 +/- 10.4; P = 0.80). The mean follow-up period for implant was longer at 40.1 months compared with 16.2 months for inject (P = 0.001). Operative time for implant was slightly longer at 111 min versus 106 min for inject (P = 0.51). Graft function was achieved in 27 (87.1%) implant patients and 20 (69%) inject patients (P = 0.08). Recurrence was seen in four (12.9%) implant patients compared with one (2.9%) inject patient, after a mean period of 28.8 months. This difference was not statistically significant (P = 0.18). CONCLUSIONS: Intramuscular injection of parathyroid tissue is a feasible alternative to surgical transplantation by implantation after total parathyroidectomy in tertiary hyperparathyroidism. The injection method was slightly faster to perform. However, injection achieved a slightly lower graft function rate but the risk of autograft hyperplasia also was lower.

Reoperative adrenal surgery: lessons learnt.

With the widespread use of abdominal imaging, the detection and therefore incidence of adrenal tumours is increasing. The laparoscopic approach to primary surgical resection of adrenal tumours has now become the standard of care. There is scarce published literature regarding the management and outcomes of recurrent adrenal tumours. The aim of the present study was therefore to review the authors' experience with reoperative adrenal surgery. A retrospective review of reoperative adrenalectomy cases identified from the prospectively maintained University of Sydney Endocrine Surgical Unit Database from January 1988 to July 2007 was carried out. There were nine (3.5%) reoperative adrenalectomies in six patients. Two were cases of adrenocortical carcinoma, two involved cases of familial phaeochromocytomas and two cases were due to sporadic phaeochromocytomas. Reoperative adrenal surgery is an uncommon event. During the index surgery for adrenal tumours, all adrenal tissue should be removed and knowledge of the vagaries of adrenal anatomy is essential. Reoperative adrenal surgery is a safe procedure and may confer survival benefit or symptom relief. Lifelong follow up is essential for all patients who have had surgery for functional and malignant adrenal tumours.

Management of hyperfunctioning single thyroid nodules in the era of minimally invasive thyroid surgery.

Both surgical excision and radioiodine ablation are effective modalities in the management of hyperfunctioning thyroid nodules. Minimally invasive thyroid surgery (MITS) using the lateral mini-incision approach has previously been demonstrated to be a safe and effective technique for thyroid lobectomy. As such MITS may offer advantages as a surgical approach to hyperfunctioning thyroid nodules without the need for a long cervical incision or extensive dissection associated with formal open hemithyroidectomy. The aim of the present study was to assess the safety and efficacy of MITS for the treatment of hyperfunctioning thyroid nodules. This is a retrospective case study. Data were obtained from the University of Sydney Endocrine Surgical Unit Database from 2002 to 2007. There were 86 cases of hyperfunctioning thyroid nodules surgically removed during the study period, of which 10 (12%) were managed using the MITS approach. The ipsilateral recurrent laryngeal nerve was identified and preserved in all cases with no incidence of temporary or permanent nerve palsy. The external branch of the superior laryngeal nerve was visualized and preserved in eight cases (80%). There were no cases of postoperative bleeding. There was one clinically significant follicular thyroid carcinoma in the series (10%). In nine of 10 cases (90%) normalization of thyroid function followed surgery. MITS is a safe and effective procedure, achieving the benefits of a minimally invasive procedure with minimal morbidity. As such it now presents an attractive alternative to radioiodine ablation for the management of small hyperfunctioning thyroid nodules.