COVID-19 vaccines and adverse events of special interest: A multinational Global Vaccine Data Network (GVDN) cohort study of 99 million vaccinated individuals

BACKGROUND

The Global COVID Vaccine Safety (GCoVS) Project, established in 2021 under the multinational Global Vaccine Data Network™ (GVDN®), facilitates comprehensive assessment of vaccine safety. This study aimed to evaluate the risk of adverse events of special interest (AESI) following COVID-19 vaccination from 10 sites across eight countries.

METHODS

Using a common protocol, this observational cohort study compared observed with expected rates of 13 selected AESI across neurological, haematological, and cardiac outcomes. Expected rates were obtained by participating sites using pre-COVID-19 vaccination healthcare data stratified by age and sex. Observed rates were reported from the same healthcare datasets since COVID-19 vaccination program rollout. AESI occurring up to 42 days following vaccination with mRNA (BNT162b2 and mRNA-1273) and adenovirus-vector (ChAdOx1) vaccines were included in the primary analysis. Risks were assessed using observed versus expected (OE) ratios with 95 % confidence intervals. Prioritised potential safety signals were those with lower bound of the 95 % confidence interval (LBCI) greater than 1.5.

RESULTS

Participants included 99,068,901 vaccinated individuals. In total, 183,559,462 doses of BNT162b2, 36,178,442 doses of mRNA-1273, and 23,093,399 doses of ChAdOx1 were administered across participating sites in the study period. Risk periods following homologous vaccination schedules contributed 23,168,335 person-years of follow-up. OE ratios with LBCI > 1.5 were observed for Guillain-Barré syndrome (2.49, 95 % CI: 2.15, 2.87) and cerebral venous sinus thrombosis (3.23, 95 % CI: 2.51, 4.09) following the first dose of ChAdOx1 vaccine. Acute disseminated encephalomyelitis showed an OE ratio of 3.78 (95 % CI: 1.52, 7.78) following the first dose of mRNA-1273 vaccine. The OE ratios for myocarditis and pericarditis following BNT162b2, mRNA-1273, and ChAdOx1 were significantly increased with LBCIs > 1.5.

CONCLUSION

This multi-country analysis confirmed pre-established safety signals for myocarditis, pericarditis, Guillain-Barré syndrome, and cerebral venous sinus thrombosis. Other potential safety signals that require further investigation were identified.

Cytomegalovirus Retinitis Associated With Intravitreal Dexamethasone Implant Injection

Purpose: To describe an immunocompetent patient with cytomegalovirus (CMV) retinitis after dexamethasone implant injection and review previously documented cases. Methods: A review of case reports and literature was performed. Results: A 75-year-old man presented with acute decreased vision in the left eye. He had a vitrectomy and membrane peeling for an epiretinal membrane with recurrent cystoid macular edema and was receiving intravitreal dexamethasone implant injections at an outside hospital. The visual acuity in the left eye was hand motions, and an examination found patchy retinal whitening with hemorrhages. Aqueous polymerase chain reaction was positive for CMV. The laboratory evaluation was negative for immunodeficiencies. He was treated successfully with intravitreal and oral antivirals; however, his vision remained poor at most recent follow-up. A literature review found 8 previous cases of CMV retinitis after dexamethasone implant injection, although most had underlying immune dysregulation. Conclusions: CMV retinitis after intravitreal dexamethasone implant injection is rare. Awareness of this complication is essential because of the risk for devastating blindness.

The Impact of TP53 Mutations and Use of the TP53-Mutation-Reactivating Agent APR-246 on Metastatic Castrate-Sensitive Prostate Cancer

PURPOSE/OBJECTIVE(S)

TP53 mutations appear to be enriched over the spectrum of metastatic castration-sensitive prostate cancer (mCSPC) and are associated with worse survival outcomes. We chose to further explore the impact of dominant negative (DN) TP53 mutations on mCSPC progression and pro-metastatic behaviors in addition to studying the ability of APR-246, a small molecule targeting TP53 mutants, to blunt pro-metastatic behaviors.

MATERIALS/METHODS

We retrospectively analyzed 531 mCSPC patients who underwent next-generation sequencing. Patients were stratified by metastasis timing (synchronous if metastasis present at diagnosis or metachronous if arising after definitive treatment of localized disease) and the number of metastatic lesions (oligometastatic ≤5 or polymetastatic >5 lesions). Tumors were classified based on TP53 mutation status (missense, truncating, or wild-type [WT]) and dominant negativity, which was defined as the production of a mutant protein that reduces the residual WT protein's transcriptional activity according to the World Health Organization TP53 database. Clinical outcomes were radiographic progression-free survival (rPFS) and overall survival (OS), evaluated with Kaplan-Meier and multivariable Cox regression. To verify the impact of TP53 mutation on metastasis, we created isogenic 22Rv1 prostate cancer cell lines that carried either TP53 WT or TP53 R175H and tested this mutation for migration, invasion, and anchorage-independent growth. APR-246 (25-80 µM) was tested for anti-metastatic properties in vitro and anti-tumor growth in 22Rv1 xenografted nude mice.

RESULTS

In our cohort, 155 (29.2%) had a TP53 mutation, which mostly occurred in the DNA-binding domain (85.16%). DN TP53 mutations were associated with more aggressive disease states: DN TP53 mutations were enriched in patients with synchronous (vs. metachronous: 20.7% vs. 6.3%, p < 0.01) and polymetastatic disease (vs. oligometastatic: 14.4% vs. 7.9%, p < 0.01). On multivariable analysis, DN TP53 mutations were correlated with shorter rPFS (HR = 1.97, 95% CI: 1.31-2.98, p < 0.01) and OS (HR = 2.05, 95% CI: 1.14-3.68, p = 0.02) compared to those with TP53 WT. In vitro, 22Rv1 cells with DN TP53 R175H mutation had increased abilities to migrate, invade, and form colonies compared to TP53 WT. APR-246 treatment of TP53 R175H mutants blunted the pro-metastatic effects of the cell line in vitro (p < 0.01 for all assays by unpaired t-test). Interestingly, APR-246 also inhibited xenograft tumor growth of 22Rv1 TP53 R175H mutants (p < 0.0001 by two-way ANOVA).

CONCLUSION

DN TP53 mutations were associated with poorer survival outcomes for mCSPC patients. DN TP53 mutations also promoted prostate cancer pro-metastatic behaviors in vitro, which was effectively counteracted by APR-246, making it a promising treatment option that should be explored further in early-phase clinical studies.

Transcriptomic Heterogeneity of Metastatic Disease Timing within Metastatic Castration-Sensitive Prostate Cancer

PURPOSE/OBJECTIVE(S)

Metastatic castration-sensitive prostate cancer (mCSPC) is commonly partitioned into high- and low-volume subgroups which have demonstrated differential biology, prognosis, and response to therapy. Timing of metastasis has similarly demonstrated differences in clinical outcomes, however less is known about any potential underlying biologic differences between these disease states. Herein we aim to compare transcriptomic differences between synchronous and metachronous mCSPC and identify any differential responses to therapy.

MATERIALS/METHODS

We performed an international multi-institutional retrospective review of men with mCSPC who completed RNA expression profiling evaluation of their primary tumor. Patients were stratified according to disease timing (synchronous vs metachronous). The primary endpoint was to identify differences in transcriptomic profiles between disease time. Median genomic scores between groups were compared with Mann-Whitney U test. Secondary analyses included determining clinical and transcriptomic variables associated with overall survival (OS) from time of metastasis. Survival analysis was performed with the Kaplan-Meier Method and Multivariable Cox regression.

RESULTS

A total of 252 patients were included with a median follow-up of 39.6 months. Patients with synchronous disease experienced worse 5-yr OS (39% vs 79%, p<0.01) and demonstrated lower median Androgen Receptor Activity (AR-A) (11.78 vs 12.64, p<0.01) and Hallmark Androgen Response (HAR) (3.15 vs 3.32; p<0.01). Multivariable cox-regression identified only high-volume disease (HR = 4.97, 95% CI 2.71-9.10; p<0.01) and HAR score (HR = 0.51, 95% CI 0.28-0.88; p = 0.02 significantly associated with OS. Finally, patients with synchronous (HR = 0.47, 95% CI 0.30-0.72; <0.01) but not metachronous (HR = 1.37, 95% CI 0.50-3.92; p = 0.56) disease were found to have better OS with Androgen Receptor (AR) + non-AR combination therapy as compared to monotherapy (p value for interaction = 0.05).

CONCLUSION

We have demonstrated a potential biologic difference between metastatic timing of mCSPC. Specifically, for patients with low volume disease, those with metachronous low volume disease have a more hormone dependent transcriptional profile and exhibit a better prognosis than synchronous low volume disease.

Identification of a Predictive Genomic Biomarker for Prostate Directed Therapy in Synchronous Low-Volume Metastatic Castration Sensitive Prostate Cancer

PURPOSE/OBJECTIVE(S)

Standard of care management for metastatic castration sensitive prostate cancer (mCSPC) includes androgen deprivation therapy (ADT) with docetaxel or second-generation anti-androgen therapy. Recently, randomized data has demonstrated radiotherapy to the prostate is associated with an improvement in overall survival among patients with low-volume metastatic disease. Tumor genomics represents an additional dimension to understand the clinical trajectory of patients with mCSPC. Herein we aim to evaluate a high-risk genomic signature for its ability to predict response to prostate directed therapy (PDT).

MATERIALS/METHODS

We performed a single institution retrospective review of men with low-volume mCSPC who underwent next-generation sequencing of their tumor. Patients were classified according to the presence of high-risk (HiRi) mutation including pathogenic mutations in either TP53, ATM, BRCA1/2, or Rb1. Our primary endpoint was to determine the effect of PDT on overall survival (OS) in patients with and without a HiRi mutation. Survival analysis was performed with the Kaplan-Meier method compared with log-rank test and multivariable cox regression. Interaction between HiRi mutation and PDT was evaluated.

RESULTS

A total of 101 patients with synchronous low-volume CSPC were included in our analysis with a median follow-up of 44 months. Approximately half of patients were found to have a HiRi pathogenic mutation (48.5%) with TP53 mutations accounting for 75.5% of HiRi mutations. On multivariable cox regression PDT was associated with improvement in OS (HR = 0.37, 95% CI 0.16-0.88; p = 0.03). When stratified by presence of HiRi mutation, PDT was not associated with any clinical outcome. Patients with HiRi mutations demonstrated a median OS of 73 vs 66.8 months (p = 0.28) for no PDT and PDT, respectively. Conversely, patients without a HiRi mutation demonstrated a significant improvement in median OS of 60 vs 105.3 months (p<0.01) for no PDT and PDT, respectively. The p-value for interaction for OS between PDT and HiRi mutation was statistically significant (p<0.01).

CONCLUSION

Here we have identified a high-risk genomic biomarker that appears predictive for response to PDT in men with synchronous low-volume mCSPC. Further work validating these results with prospective randomized data is warranted.

Prognostic Significance of Pretreatment Immune Cell Infiltration in Muscle Invasive Bladder Cancer Treated with Definitive Chemoradiation: Analysis of NRG RTOG 0524 and 0712

PURPOSE/OBJECTIVE(S)

Chemoradiation therapy (CRT) is an organ conserving approach in the treatment of locally advanced bladder cancer. Chemoradiation is thought to potentially result in immunogenic stimulation, and bladder cancer is often a tumor with high immune cell infiltration. Thus, we aimed to profile the tumor immune microenvironment of bladder cancer and identify prognostic immune biomarkers for CRT response by profiling tumor samples from NRG/RTOG 0524 and 0712, two prospective trials of CRT in muscle invasive bladder cancer (MIBC).

MATERIALS/METHODS

Pretreatment tissue samples from both trials were profiled using Cofactor Genomics ImmunoPrism, an RNA sequencing assay that uses gene expression profiles to quantify immune cell populations in the tumor microenvironment (TME). Differential gene expression was estimated for different immune cell type proportions across samples. Kaplan-Meier survival analysis and log rank tests were performed to evaluate differences in overall survival (OS) stratified by genes influenced by immune cell proportions or genes associated with immune response signatures.

RESULTS

A total of 70 samples (43 from RTOG 0524 and 27 from RTOG 0712) underwent analysis using the ImmunoPrism assay. Immune cell proportions were as follows: CD8 T cells: median 1.2%, CD4 T cells: median 0.8%, Treg cells: median 9.2%, CD19 B cells: median 5.1%, M2 macrophages: median 0.8%, M1 macrophages: median 0%. Unbiased clustering based on gene expression profiles driven by immune cell proportions demonstrated two groups: cluster 1 with a low percentage of immune cells and shorter OS (median 31 months) and cluster 2 with a high percentage of immune cells and longer OS (median 101 months, p = 0.036). Higher expression of genes associated with T cell infiltration (CD8A and ICOS) was associated with improved OS (104 vs 35 months, p = 0.028, HR = 0.48 (0.25 - 0.94), p = 0.031) as was higher expression of IDO1, which is associated with the interferon gamma pathway (104 vs 35 months, p = 0.042, HR = 0.49 (0.24 - 0.99), p = 0.046).

CONCLUSION

Bladder tumors have a wide range of immune cell infiltration in the TME. Increased immune cell proportions are prognostic for OS following CRT, as well as a higher expression of genes associated with T cell infiltration interferon gamma signaling. These findings have implications for the integration of immunotherapy in the definitive management of MIBC; and can be explored further in the ongoing NRG/SWOG 1806 trial.

Safety and efficacy of tenecteplase in patients with wake-up stroke assessed by non-contrast CT (TWIST): a multicentre, open-label, randomised controlled trial

BACKGROUND

Current evidence supports the use of intravenous thrombolysis with alteplase in patients with wake-up stroke selected with MRI or perfusion imaging and is recommended in clinical guidelines. However, access to advanced imaging techniques is often scarce. We aimed to determine whether thrombolytic treatment with intravenous tenecteplase given within 4·5 h of awakening improves functional outcome in patients with ischaemic wake-up stroke selected using non-contrast CT.

METHODS

TWIST was an investigator-initiated, multicentre, open-label, randomised controlled trial with blinded endpoint assessment, conducted at 77 hospitals in ten countries. We included patients aged 18 years or older with acute ischaemic stroke symptoms upon awakening, limb weakness, a National Institutes of Health Stroke Scale (NIHSS) score of 3 or higher or aphasia, a non-contrast CT examination of the head, and the ability to receive tenecteplase within 4·5 h of awakening. Patients were randomly assigned (1:1) to either a single intravenous bolus of tenecteplase 0·25 mg per kg of bodyweight (maximum 25 mg) or control (no thrombolysis) using a central, web-based, computer-generated randomisation schedule. Trained research personnel, who conducted telephone interviews at 90 days (follow-up), were masked to treatment allocation. Clinical assessments were performed on day 1 (at baseline) and day 7 of hospital admission (or at discharge, whichever occurred first). The primary outcome was functional outcome assessed by the modified Rankin Scale (mRS) at 90 days and analysed using ordinal logistic regression in the intention-to-treat population. This trial is registered with EudraCT (2014-000096-80), ClinicalTrials.gov (NCT03181360), and ISRCTN (10601890).

FINDINGS

From June 12, 2017, to Sept 30, 2021, 578 of the required 600 patients were enrolled (288 randomly assigned to the tenecteplase group and 290 to the control group [intention-to-treat population]). The median age of participants was 73·7 years (IQR 65·9-81·1). 332 (57%) of 578 participants were male and 246 (43%) were female. Treatment with tenecteplase was not associated with better functional outcome, according to mRS score at 90 days (adjusted OR 1·18, 95% CI 0·88-1·58; p=0·27). Mortality at 90 days did not significantly differ between treatment groups (28 [10%] patients in the tenecteplase group and 23 [8%] in the control group; adjusted HR 1·29, 95% CI 0·74-2·26; p=0·37). Symptomatic intracranial haemorrhage occurred in six (2%) patients in the tenecteplase group versus three (1%) in the control group (adjusted OR 2·17, 95% CI 0·53-8·87; p=0·28), whereas any intracranial haemorrhage occurred in 33 (11%) versus 30 (10%) patients (adjusted OR 1·14, 0·67-1·94; p=0·64).

INTERPRETATION

In patients with wake-up stroke selected with non-contrast CT, treatment with tenecteplase was not associated with better functional outcome at 90 days. The number of symptomatic haemorrhages and any intracranial haemorrhages in both treatment groups was similar to findings from previous trials of wake-up stroke patients selected using advanced imaging. Current evidence does not support treatment with tenecteplase in patients selected with non-contrast CT.

FUNDING

Norwegian Clinical Research Therapy in the Specialist Health Services Programme, the Swiss Heart Foundation, the British Heart Foundation, and the Norwegian National Association for Public Health.

Association between ambulatory skills and diffusion tensor imaging of corpus callosal white matter in infants with spina bifida

OBJECTIVES

To assess brain white matter using diffusion tensor imaging (DTI) at 1 year of age in infants diagnosed with open neural tube defect (ONTD) and explore the association of DTI parameters with ambulatory skills at 30 months of age.

METHODS

Magnetic resonance imaging (MRI) was performed at an average of 12 months of age and included an echo planar axial DTI sequence with diffusion gradients along 20 non-collinear directions. TORTOISE software was used to correct DTI raw data for motion artifacts, and DtiStudio, DiffeoMap and RoiEditor were used for further postprocessing. DTI data were analyzed in terms of fractional anisotropy (FA), trace, radial diffusivity and axial diffusivity. These parameters reflect the integrity and maturation of white-matter motor pathways. At 30 months of age, ambulation status was evaluated by a developmental pediatrician, and infants were classified as ambulatory if they were able to walk independently with or without orthoses or as non-ambulatory if they could not. Linear mixed-effects method was used to examine the association between study outcomes and study group. Possible confounders were sought, and analyses were adjusted for age at MRI scan and ventricular size by including them in the regression model as covariates.

RESULTS

Twenty patients with ONTD were included in this study, including three cases that underwent postnatal repair and 17 cases that underwent prenatal repair. There were five ambulatory and 15 non-ambulatory infants evaluated at a mean age of 31.5 ± 5.7 months. MRI was performed at 50.3 (2-132.4) weeks postpartum. When DTI analysis results were compared between ambulatory and non-ambulatory infants, significant differences were observed in the corpus callosum (CC). Compared with non-ambulatory infants, ambulatory infants had increased FA in the splenium (0.62 (0.48-0.75) vs 0.41 (0.34-0.49); P = 0.01, adjusted P = 0.02), genu (0.64 (0.47-0.80) vs 0.47 (0.35-0.61); P = 0.03, adjusted P = 0.004) and body (0.55 (0.45-0.65) vs 0.40 (0.35-0.46), P = 0.01, adjusted P = 0.01). Reduced trace was observed in the CC of ambulatory children at the level of the splenium (0.0027 (0.0018-0.0037) vs 0.0039 (0.0034-0.0044) mm² /s; P = 0.04, adjusted P = 0.03) and genu (0.0029 (0.0020-0.0038) vs 0.0039 (0.0033-0.0045) mm² /s; P = 0.04, adjusted P = 0.01). In addition, radial diffusivity was reduced in the CC of the ambulatory children at the level of the splenium (0.00057 (0.00025-0.00089) vs 0.0010 (0.00084-0.00120) mm² /s; P = 0.02, adjusted P = 0.02) and the genu (0.00058 (0.00028-0.00088) vs 0.0010 (0.00085-0.00118) mm² /s; P = 0.02, adjusted P = 0.02). There were no differences in axial diffusivity between ambulatory and non-ambulatory children.

CONCLUSION

This study demonstrates a significant association between white matter integrity of connecting fibers of the corpus callosum, as assessed by DTI, and ambulatory skills at 30 months of age in infants with ONTD. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Measuring the Metabolic Evolution of Glioblastoma throughout Tumor Development, Regression, and Recurrence with Hyperpolarized Magnetic Resonance

Rapid diagnosis and therapeutic monitoring of aggressive diseases such as glioblastoma can improve patient survival by providing physicians the time to optimally deliver treatment. This research tested whether metabolic imaging with hyperpolarized MRI could detect changes in tumor progression faster than conventional anatomic MRI in patient-derived glioblastoma murine models. To capture the dynamic nature of cancer metabolism, hyperpolarized MRI, NMR spectroscopy, and immunohistochemistry were performed at several time-points during tumor development, regression, and recurrence. Hyperpolarized MRI detected significant changes of metabolism throughout tumor progression whereas conventional MRI was less sensitive. This was accompanied by aberrations in amino acid and phospholipid lipid metabolism and MCT1 expression. Hyperpolarized MRI can help address clinical challenges such as identifying malignant disease prior to aggressive growth, differentiating pseudoprogression from true progression, and predicting relapse. The individual evolution of these metabolic assays as well as their correlations with one another provides context for further academic research.

Clinical utility of skin cancer and melanoma risk scores for population screening: TRoPICS study

BACKGROUND

Screening for skin cancer can be cost-effective if focused on high-risk groups. Risk prediction tools have been developed for keratinocyte cancers and melanoma to optimize advice and management. However, few have been validated in a clinical setting over the past few years.

OBJECTIVES

To assess the clinical utility of risk assessment tools to identify individuals with prevalent skin cancers in a volunteer-based screening clinic.

METHODS

Participants were adults presenting for a skin check at a volunteer-based skin cancer screening facility. We used previously published tools, based on questionnaire responses, to predict melanoma and keratinocyte cancers [KCs; basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)] and classified each participant into one of five risk categories. Participants subsequently underwent a full skin examination by a dermatologist. All suspicious lesions were biopsied, and all cancers were histopathologically confirmed.

RESULTS

Of 789 people who presented to the clinic, 507 (64%) consented to the study. Twenty-two BCCs, 19 SCCs and eight melanomas were diagnosed. The proportion of keratinocyte cancers diagnosed increased according to risk category from <1% in the lowest to 24% in the highest risk category (P < 0.001). Subtype analysis revealed similar proportionate increases in BCC or SCC prevalence according to risk category. However, a similar proportion of melanoma cases were detected in the low-risk and high-risk groups.

CONCLUSION

The risk prediction model for keratinocyte cancers can reliably identify individuals with a significant skin cancer burden prior to a skin examination in the community setting. The prediction tool for melanoma needs to be tested in a larger sample exposed to a wider range of environmental risk factors.

A comparative study evaluating the role of adductor canal block catheter versus intraarticular analgesic infusion on knee pain and range of motion in the immediate postoperative period: a prospective multicenter trial

Postoperative pain after total knee arthroplasty (TKA) is an important determinant of hospital stay and rehabilitation and thereby functional outcome. Adductor canal block (ACB) and intraarticular analgesic infiltration through catheters (IAC) are techniques of multimodal analgesia which have shown to control postoperative pain satisfactorily. The aim of this study is to evaluate the efficacy of ACB versus IAC in reducing immediate postoperative pain and thereby allow early rehabilitation. A multicenter quasi-experimental study was conducted on 511 patients undergoing unilateral primary TKA from March 2016 to April 2017 who either received ACB with catheter (Group I, n = 350 patients) or IAC (Group II, n = 172 patients) for postoperative pain control. All the patients were assessed for severity of pain by Visual Analogue Scale at 8, 24, 48, 72 h postoperatively and knee range of motion (ROM) on the day of discharge. There was no significant difference in pain scores on postoperative day (POD) 0 (1.09 ± 0.30 vs. 0.98 ± 0.46, p = 0.45) and POD 1 (1.21 ± 0.45 vs. 1.00 ± 0.00, p = 0.11) and in mean ROM on the day of discharge between ACB and IAC (88.40° ± 7.96° vs. 88.34° ± 5.74°; p = 0.93) groups. This study shows that both ACB and IAC provide satisfactory postoperative analgesia with sparing of quadriceps function and good knee ROM leading to early rehabilitation and reduced hospital with no advantage of one technique over another.

Better one or two? A systematic review of portable automated refractors

INTRODUCTION

More than 400 million people suffer from visual impairment globally, with more than half due to uncorrected refractive error. Autorefraction (AR) is the most common examination performed prior to prescribing glasses. As technology advances, so has the accuracy and number of portable autorefractors available. Portable technology has become acutely important with the coronavirus disease 2019 pandemic and the conversion of in-person clinical evaluations to remote telemedicine encounters. Patients and providers want to do as much as possible remotely. The aim of this study was to conduct a systematic literature review of the accuracy and effectiveness of available portable automated refractors compared to the current standard of care, subjective refraction (SR).

METHODS

A literature search of PubMED, Embase and ClinicalTrials.gov 97 unique publications in English on portable autorefractors. Twelve studies comparing a portable AR device to at least one form of SR were systematically included in this review.

RESULTS

There were four portable autorefractors (Netra, Quicksee, Retinomax and SVOne) studied against SR. There was high patient acceptance of glasses prescriptions by the Quicksee alone, with 87% subjects seeing the same or better than SR. Quicksee was more accurate than Netra and Retinomax. SVOne was preferred over Netra and outperformed Retinomax in multiple measures, despite Retinomax being the fastest test.

DISCUSSION

There are numerous portable autorefractors available, but few were compared against SR. Quicksee and SVOne are the most accurate and patient-preferred devices. Quicksee was the most accurate, and it performed clinically the same as SR in some reports.

Homeostasis and Defense at the Surface of the Eye. The Conjunctival Microbiota

The literature on ocular microbiome has grown tremendously over the past decade, and our knowledge of the different aspects and roles in homeostasis and protection is continuously growing. The development of 16 S rRNA sequencing has allowed the field to characterize communities of bacteria in health and ocular disease. Efforts should continue to further elucidate the interplay between microbiome and key players, such as age, comorbidities, and contact lens usage in order to have better control of the sight-threatening complications.

Comparison of brain microstructure after prenatal spina bifida repair by either laparotomy-assisted fetoscopic or open approach

OBJECTIVE

To compare prenatal and postnatal brain microstructure between infants that underwent fetoscopic myelomeningocele (MMC) repair and those that had open-hysterotomy repair.

METHODS

This was a longitudinal retrospective cohort study of 57 fetuses that met the Management of Myelomeningocele Study (MOMS) trial criteria and underwent prenatal MMC repair, by a fetoscopic (n = 27) or open-hysterotomy (n = 30) approach, at 21.4-25.9 weeks' gestation. Fetoscopic repair was performed under CO₂ insufflation, according to our protocol. Diffusion-weighted magnetic resonance imaging (MRI) was performed before surgery in 30 cases (14 fetoscopic and 16 open), at 6 weeks postsurgery in 48 cases (24 fetoscopic and 24 open) and within the first year after birth in 23 infants (five fetoscopic and 18 open). Apparent diffusion coefficient (ADC) values from the basal ganglia, frontal, occipital and parietal lobes, mesencephalon and genu as well as splenium of the corpus callosum were calculated. ADC values at each of the three timepoints (presurgery, 6 weeks postsurgery and postnatally) and the percentage change in the ADC values between the timepoints were compared between the fetoscopic-repair and open-repair groups. ADC values at 6 weeks after surgery in the two prenatally repaired groups were compared with those in a control group of eight healthy fetuses that underwent MRI at a similar gestational age (GA). Comparison of ADC values was performed using the Student's t-test for independent samples (or Mann-Whitney U-test if non-normally distributed) and multivariate general linear model analysis, adjusting for GA or age at MRI and mean ventricular width.

RESULTS

There were no differences in GA at surgery or GA/postnatal age at MRI between the groups. No significant differences were observed in ADC values in any of the brain areas assessed between the open-repair and fetoscopic-repair groups at 6 weeks after surgery and in the first year after birth. No differences were detected in the ADC values of the studied areas between the control and prenatally repaired groups, except for significantly increased ADC values in the genu of the corpus callosum in the open-hysterotomy and fetoscopic-repair groups. Additionally, there were no differences between the two prenatally repaired groups in the percentage change in ADC values at any of the time intervals analyzed.

CONCLUSIONS

Fetoscopic MMC repair has no detectable effect on brain microstructure when compared to babies repaired using an open-hysterotomy technique. CO₂ insufflation of the uterine cavity during fetoscopy does not seem to have any isolated deleterious effects on fetal brain microstructure. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

A systematic review of rescue analgesic strategies in acute exacerbations of primary trigeminal neuralgia

BACKGROUND

Trigeminal neuralgia (TN) can have a significant impact on wellbeing and quality of life. Limited data exist for treatments that improve TN pain acutely, within 24 h of administration. This systematic review aims to identify effective treatments that acutely relieve TN exacerbations.

METHODS

We searched Medline and Cochrane Central Register of Controlled Trials (CENTRAL) for relevant English language publications. The reference list for all articles was searched for other relevant publications. All studies that satisfied the following PICO criteria were included: (i) Population-adults with acute exacerbation of primary TN symptoms; (ii) Intervention-any medication or intervention with the primary goal of pain relief within 24 h; (iii) Comparator-usual medical care, placebo, sham or active treatment; (iv) Outcome-more than 50% reduction in pain intensity within 24 h of administration.

RESULTS

Of 431 studies, 17 studies were identified that reported immediate results of acute treatment in TN. The evidence suggests that the following interventions may be beneficial: local anaesthetic, mainly lidocaine (ophthalmic, nasal or oral mucosa, trigger point injection, i.v. infusion, nerve block); anticonvulsant, phenytoin or fosphenytoin (i.v. infusion); serotonin agonist, sumatriptan (s.c. injection, nasal). Other referenced interventions with very limited evidence include N-methyl-d-aspartate receptor antagonist (magnesium sulphate infusion) and botulinum toxin (trigger point injection).

CONCLUSIONS

Several treatment options exist that may provide fast and safe relief of TN. Future studies should report on outcomes within 24 h to improve knowledge of the acute analgesic TN treatments.

Prenatal brain imaging for predicting need for postnatal hydrocephalus treatment in fetuses that had neural tube defect repair in utero

OBJECTIVE

To determine if brain imaging in fetuses that underwent prenatal repair of neural tube defect (NTD) can predict the need for postnatal hydrocephalus treatment (HT) in the first year postpartum.

METHODS

This was a retrospective study of fetuses diagnosed with open NTD that had in-utero myelomeningocele repair between April 2014 and April 2016. Independent variables were collected from four chronological sets of fetal images: presurgery ultrasound, presurgery magnetic resonance imaging (MRI), 6-week postsurgery MRI and predelivery ultrasound. The following independent variables were collected from all image sets unless otherwise noted: gestational age, head circumference, mean ventricular width, ventricular volume (MRI only), hindbrain herniation (HBH) score (MRI only), and level of lesion (LOL), defined as the upper bony spinal defect (presurgery ultrasound only). Based on these measurements, additional variables were defined and calculated including change in degree of HBH, ventricular width growth (mm/week) and ventricular volume growth (mL/week). The need for HT (by either ventriculoperitoneal shunt or endoscopic third ventriculostomy with choroid plexus cauterization) was determined by a pediatric neurosurgeon using clinical and radiographic criteria; a secondary analysis was performed using the MOMS trial criteria for hydrocephalus. The predictive value of each parameter was assessed by receiver-operating characteristics curve and logistic regression analyses.

RESULTS

Fifty affected fetuses were included in the study, of which 32 underwent open hysterotomy and 18 fetoscopic repair. Two neonates from the open hysterotomy group died and were excluded from the analysis. The mean gestational ages for the presurgery ultrasound, presurgery MRI, postsurgery MRI and predelivery ultrasound were 21.8 ± 2.1, 22.0 ± 1.8, 30.4 ± 1.6 and 31.0 ± 4.9 weeks, respectively. A total of 16 subjects required HT. The area under the curve (AUC) of predictive accuracy for HT showed that HBH grading on postsurgery MRI had the strongest predictive value (0.86; P < 0.01), outperforming other predictors such as postsurgery MRI ventricular volume (0.73; P = 0.03), MRI ventricular volume growth (0.79; P = 0.01), change in HBH (0.82; P = 0.01), and mean ventricular width on predelivery ultrasound (0.73; P = 0.01). Other variables, such as LOL, mean ventricular width on presurgery ultrasound, mean ventricular width on presurgery and postsurgery MRI, and ventricular growth assessment by MRI or ultrasound, had AUCs < 0.7. Optimal cut-offs of the variables with the highest AUC were evaluated to improve prediction. A combination of ventricular volume growth ≥ 2.02 mL/week and/or HBH of 3 on postsurgery MRI were the optimal cut-offs for the best prediction (odds ratio (OR), 42 (95% CI, 4-431); accuracy, 84%). Logistic regression analyses showed that persistence of severe HBH 6 weeks after surgery by MRI is one of the best predictors for HT (OR, 39 (95% CI, 4-369); accuracy, 84%). There was no significant change in the results when the MOMS trial criteria for hydrocephalus were used as the dependent variable.

CONCLUSIONS

Persistence of HBH on MRI 6 weeks after prenatal NTD repair independently predicted the need for postnatal HT better than any ultrasound- or other MRI-derived measurements of ventricular characteristics. These results should aid in prenatal counseling and add support to the hypothesis that HBH is a significant driver of hydrocephalus in myelomeningocele patients. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Mismatch of long Gamma intramedullary nail with bow of the femur: Does radius of curvature of the nail increase risk of distal femoral complications?

INTRODUCTION

Anterior cortical penetration of the distal nail tip is a recognized complication of intra-medullary nailing of the femur particularly in the geriatric population. This has been attributed to a mismatch between the femoral bow and the radius of curvature (ROC) of the femoral nail. We wanted to see if there was a reduction of this risk comparing cephalomedullary nails with ROC of 200 cm and 150 cm.

METHODS

52 patients were split into 2 groups similar with respect to age, sex and comorbidities. Group A with 25 patients used a nail with a ROC of 200 cm and Group B with 27 patients used a 150 cm ROC nail. Lateral radiographs of the distal femur were evaluated to note the position of the nail tip in relation to the femoral canal. The diameter of the femur at the tip of the nail was divided into 3 equal zones. The anterior one-third was designated as Zone1, the middle one-third as Zone 2 and the posterior one-third as Zone 3.

RESULTS

80% of the cases with a 200 cm ROC nail had the tip of the nail in the anterior one-third of the canal (zone 1). Fracture of the anterior femoral cortex distally by the nail tip was seen in 2 patients.Only 18.5% of cases with a 150 cm ROC nail had the tip of the nail in anterior one-third of the canal (zone 1). There were no incidences of complications such as fractures and anterior cortical perforation.

CONCLUSIONS

A cephalomedullary nail with a ROC of 150 cm had its distal tip more towards the center of the femoral canal when compared to a nail with ROC of 200 cm. No case of anterior femoral penetration was seen when using a nail with an ROC of 150 cm.

Rare case of atypical femoral fracture with blocked medullary canal associated with bisphosphonate therapy

Bisphosphonates are widely used for treatment of osteoporosis and its use is increasing in geriatric population. Atypical femoral fractures are associated with bisphosphonate therapy. We report an unusual case of femoral shaft fracture following bisphosphonate therapy where the femoral canal of the proximal and distal fracture fragments was blocked and its management.

Evaluation of Mycotube, a modified version of Lowenstein-Jensen (LJ) medium, for efficient recovery of Mycobacterium tuberculosis (MTB)

Timely diagnosis of tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), is only achieved for ~58% cases. An improved, accurate, time- and cost-effective method for bacteriological confirmation of MTB is necessary. We evaluated Mycotube, a new variant of Lowenstein-Jensen (LJ) culture medium, by comparing it with Mycobacterium Growth Indicator Tube (MGIT) 960 (gold standard), local LJ, and bioMérieux LJ-T in terms of isolation rate and time-to-growth. Pulmonary and extra-pulmonary samples from treatment-naïve suspects (n = 207) were decontaminated by the N-acetyl-L-cysteine-sodium hydroxide method and used to inoculate the four media. Subjective and objective parameters were used for evaluation. Mycotube yielded 140 positive results, compared to 162, 69, and 141 from MGIT, local LJ, and LJ-T, respectively. Of these, 139 (67%) were true-positive results and 1 (0.5%) was false-positive. The mean time-to-growth detection was 17.4 days for Mycotube, compared to 14.5, 28.1, and 16.5 days for MGIT, local LJ, and LJ-T, respectively. The mean time-to-growth for local LJ significantly differed from that for MGIT, but not those for LJ-T and Mycotube. No contamination was observed. Mycotube had a sensitivity of 85.8% and a specificity of 97.8% as compared to MGIT. Mycotube offers good results, comparable with those observed for conventional LJ. It requires only basic laboratory infrastructure. The overall cost of the test should be nearly three times lower than that of MGIT. Mycotube helps with TB diagnosis and generates pure isolates for drug susceptibility testing.

Redefining MTBDRplus test results: what do indeterminate results actually mean?

BACKGROUND

Although line-probe assays (LPAs) are promising, little research has been conducted to elucidate the true nature of indeterminate LPA results or assess the ability of these assays to perform on a wide range of clinical samples.

OBJECTIVE

To evaluate the performance of the commercially available GenoType(®) MTBDRplus LPA against conventional BACTEC™ MGIT™ 960 culture and drug susceptibility testing (DST) among 308 pulmonary tuberculosis (PTB) and 32 extra-pulmonary TB samples.

RESULTS

Invalid LPA results (defined as those with a missing Mycobacterium tuberculosis identification band) were obtained for 18 PTB samples, which were excluded from further analysis. The sensitivity and specificity of the MTBDRplus assay for multidrug-resistant TB, based upon the results obtained for the remaining 322 samples, was respectively 95.2% and 95.1%. Of 290 PTB samples, 40 (13.7%) were indeterminate on LPA (defined as the absence of both wild-type and corresponding mutation bands) for isoniazid (INH) and/or rifampicin (RMP), and were further evaluated by pyrosequencing (PSQ). Contrary to standard LPA interpretation, INH and RMP susceptibility were confirmed by both DST and PSQ in respectively 7.5% (3/40) and 27.5% (11/40) of indeterminate samples.

CONCLUSION

PSQ was found to be a valuable and rapid technique to resolve discrepancies in LPA test results that were not interpretable.

APOL1-Associated End-Stage Renal Disease in a Living Kidney Transplant Donor

Homozygosity for apolipoprotein-L1 (APOL1) risk variants has emerged as an important predictor of renal disease in individuals of African descent over the past several years. Additionally, these risk variants may be important predictors of renal allograft failure when present in a living or deceased donor. Currently, there is no universal recommendation for screening of potential donors. We present a case of end-stage renal disease with focal segmental glomerulosclerosis in a living donor 7 years following donor nephrectomy. Genetic assessment revealed homozygosity for the G1 high-risk APOL1 variant.

The Anatomy of the Dorsal Cutaneous Branch of the Ulnar Nerve – a Safe Zone for Positioning of the 6r Portal in Wrist Arthroscopy

The dorsal branch of the ulnar nerve passes close to the 6 Radial portal used in wrist arthroscopy. We examined 20 cadaveric limbs to establish the course of this nerve. We found it consistently crossed a line between the ulnar styloid and the fourth web space at an average of 2.4 cm from the ulnar styloid (range 1.8–2.8 cm). This represented 23% (+/−2.5 STD range 19–27%) of the distance from the styloid process to the fourth web space. Recommendations are made to help avoid iatrogenic injury to the nerve during arthroscopy. The literature on the anatomy of this nerve and its variations and the clinical relevance of this knowledge are discussed.

Diagnostic accuracy of ultrasonography and magnetic resonance imaging for the detection of fetal anomalies: a blinded case-control study

OBJECTIVES

To compare the accuracy of two-dimensional ultrasound (2D-US), three-dimensional ultrasound (3D-US) and magnetic resonance imaging (MRI) for the diagnosis of congenital anomalies without prior knowledge of indications and previous imaging findings.

METHODS

This was a prospective, blinded case-control study comprising women with a singleton pregnancy with fetal congenital abnormalities identified on clinical ultrasound and those with an uncomplicated pregnancy. All women volunteered to undergo 2D-US, 3D-US and MRI, which were performed at one institution. Different examiners at a collaborating institution performed image interpretation. Sensitivity and specificity of the three imaging methods were calculated for individual anomalies, based on postnatal imaging and/or autopsy as the definitive diagnosis. Diagnostic confidence was graded on a four-point Likert scale.

RESULTS

A total of 157 singleton pregnancies were enrolled, however nine cases were excluded owing to incomplete outcome, resulting in 148 fetuses (58 cases and 90 controls) included in the final analysis. Among cases, 13 (22.4%) had central nervous system (CNS) anomalies, 40 (69.0%) had non-CNS anomalies and five (8.6%) had both CNS and non-CNS anomalies. The main findings were: (1) MRI was more sensitive than 3D-US for diagnosing CNS anomalies (MRI, 88.9% (16/18) vs 3D-US, 66.7% (12/18) vs 2D-US, 72.2% (13/18); McNemar's test for MRI vs 3D-US: P = 0.046); (2) MRI provided additional information affecting prognosis and/or counseling in 22.2% (4/18) of fetuses with CNS anomalies; (3) 2D-US, 3D-US and MRI had similar sensitivity for diagnosing non-CNS anomalies; (4) specificity for all anomalies was highest for 3D-US (MRI, 85.6% (77/90) vs 3D-US, 94.4% (85/90) vs 2D-US, 92.2% (83/90); McNemar's test for MRI vs 3D-US: P = 0.03); and (5) the confidence of MRI for ruling out certain CNS abnormalities (usually questionable for cortical dysplasias or hemorrhage) that were not confirmed after delivery was lower than it was for 2D-US and 3D-US.

CONCLUSIONS

MRI was more sensitive than ultrasonography and provided additional information that changed prognosis, counseling or management in 22.2% of fetuses with CNS anomalies. False-positive diagnoses for subtle CNS findings were higher with MRI than with ultrasonography. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Digital Imaging Capability for Caries Detection

The objective of this study was to identify the diagnostic capability of photostimulable phosphor plates (PSPs) and direct digital sensors (DDSs) in the detection of interproximal caries. Studies were identified that evaluated the diagnostic capability of PSPs and DDSs in detecting interproximal caries in human teeth, in both dentin and enamel. Histologic sections were the gold standard. This systematic review searched several electronic databases. In addition, Google Scholar and reference lists of the finally included studies were screened. QUADAS-2 was applied to evaluate the risk of bias among included studies. Six studies were finally included; 4 of which were considered homogeneous enough to conduct a meta-analysis. The meta-analysis evaluated 668 interproximal human tooth surfaces. All studies used extracted human teeth ranging from no caries present to caries into dentin. Each tooth was radiographed by both PSP and DDS technologies and then submitted for histologic analysis as the gold standard. Meta-analysis showed that intraoral digital imaging is of high specificity but low sensitivity in the detection of interproximal caries. The sensitivity and specificity for different studies with PSPs varied substantially from 15% to 54% and from 84% to 100%, respectively. Direct sensor analysis sensitivity and specificity ranged from 16% to 56% and from 90% to 100%, respectively. Newer PSP and DDS technologies had statistically significant higher sensitivities, yet the differences in diagnostic capabilities between the older and newer technologies were clinically insignificant. Both digital systems were excellent in identifying surfaces without caries (specificity) but were not sensitive enough to reliably identify interproximal surfaces with caries. Clinicians must therefore remain vigilant in performing a careful clinical examination and other diagnostic tests rather than relying solely on radiographic imaging to diagnose interproximal caries.

Knowledge Transfer Statement: This study will help clinicians make an evidence-based decision when deciding which digital radiography system to use when evaluating interproximal caries. Time, patient radiation safety, cost, and image quality are factors to be considered. The performance of the different available digital imaging systems was compared with the current gold standard—a histologic analysis—via meta-analysis.

Spontaneous pregnancy fifteen years after diagnosis of premature ovarian failure

We report an unusual case of spontaneous conception, occurring over fifteen years after the initial diagnosis of premature ovarian failure (POF). Her karyotype was 46XX. Following the diagnosis of POF, our patient was treated with hormone replacement therapy (HRT). Starting at the age of 31, she had several invitro fertilisation (IVF) cycles using donor eggs. She had two live births and one ectopic pregnancy for which she underwent laparoscopic salpingectomy. Between IVF treatment cycles she continued HRT. At the age of forty years she conceived spontaneously. The HRT was stopped at 10 weeks of amenorrhoea. She delivered a healthy baby boy at term. Following the delivery the patient had spontaneous periods every 2-3 months and did not suffer from menopausal symptoms. Her post delivery FSH and LH levels were high. We believe this is the longest interval reported between diagnosis of POF and a spontaneous conception.

Do delays in radiology lead to breaches in the 4-hour rule?

AIM

To assess trends in medical imaging requests before and after the 4-hour rule commenced and to assess the imaging time component of emergency department (ED) length of stay (LOS).

MATERIALS AND METHODS

Retrospective analysis of ED patients and imaging requests 1 year prior to and 3 years after implementation of the 4-hour rule (April to December for 2011-2014) was performed at a single adult tertiary referral Level 1 trauma hospital with Level 6 ED. Logistic regression was used to evaluate trends in the number of ED patient presentations, patient triage categories, and imaging requests for these patients. The imaging component of the total ED LOS was compared for patients who met the 4-hour target and patients who did not.

RESULTS

Compared to 2011 (before the 4-hour rule), ED presentations increased 4.74% in 2012, 12.7% in 2013, 21.28% in 2014 (p<0.01). Total imaging requests increased 23.05% in 2012, 48.04% in 2013, 60.77% in 2014 (p<0.01). For patients breaching the 4-hour rule, the mean time before radiology request was 2.4-2.8 hours; mean time from imaging request to completion was 1.2-1.3 hours; mean time from imaging completion to discharge from ED was the longest component of ED LOS (4.9-5.9 hours).

CONCLUSIONS

There has been a significant increase in imaging requests, with a trend towards more CT and less radiography requests. Imaging requests for patients who breached the 4-hour target were made on average 2.4-2.8 hours after triage and average time after imaging in itself, exceeded 4 hours. Imaging is not likely a causative factor for patients breaching the 4-hour target.

Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adults

Introduction:

Ashwagandha (Withania somnifera [L.] Dunal) has been traditionally used for various actions ranging from vitalizer, improve endurance and stamina, promote longevity, improve immunity, and male and female fertility. However, clinical studies are needed to prove the clinical efficacy of this herb, especially in cardiovascular endurance and physical performance.

Aims:

This prospective, double-blind, randomized, and placebo-controlled study evaluated the efficacy of Ashwagandha roots extract in enhancing cardiorespiratory endurance and improving the quality of life (QOL) in 50 healthy male/female athletic adults.

Materials and Methods:

Cardiorespiratory endurance was assessed by measuring the oxygen consumption at peak physical exertion (VO₂ max) levels during a 20 m shuttle run test. The World Health Organization self-reported QOL questionnaire (physical health, psychological health, social relationships, and environmental factors) was used to assess the QOL. Student's t-test was used to compare the differences in a mean and change from baseline VO₂ max levels, whereas Wilcoxon signed-rank test was used to assess changes in QOL scores from baseline in the two groups.

Results:

There was a greater increase from baseline (P < 0.0001) in the mean VO₂ max with KSM-66 Ashwagandha (n = 24) compared to placebo (n = 25) at 8 weeks (4.91 and 1.42, respectively) and at 12 weeks (5.67 and 1.86 respectively). The QOL scores for all subdomains significantly improved to a greater extent in the Ashwagandha group at 12 weeks compared to placebo (P < 0.05).

Conclusion:

The findings suggest that Ashwagandha root extract enhances the cardiorespiratory endurance and improves QOL in healthy athletic adults.

Expanding the Clinical Spectrum Associated With GLIS3 Mutations

CONTEXT

GLIS3 (GLI-similar 3) is a member of the GLI-similar zinc finger protein family encoding for a nuclear protein with 5 C2H2-type zinc finger domains. The protein is expressed early in embryogenesis and plays a critical role as both a repressor and activator of transcription. Human GLIS3 mutations are extremely rare.

OBJECTIVE

The purpose of this article was determine the phenotypic presentation of 12 patients with a variety of GLIS3 mutations.

METHODS

GLIS3 gene mutations were sought by PCR amplification and sequence analysis of exons 1 to 11. Clinical information was provided by the referring clinicians and subsequently using a questionnaire circulated to gain further information.

RESULTS

We report the first case of a patient with a compound heterozygous mutation in GLIS3 who did not present with congenital hypothyroidism. All patients presented with neonatal diabetes with a range of insulin sensitivities. Thyroid disease varied among patients. Hepatic and renal disease was common with liver dysfunction ranging from hepatitis to cirrhosis; cystic dysplasia was the most common renal manifestation. We describe new presenting features in patients with GLIS3 mutations, including craniosynostosis, hiatus hernia, atrial septal defect, splenic cyst, and choanal atresia and confirm further cases with sensorineural deafness and exocrine pancreatic insufficiency.

CONCLUSION

We report new findings within the GLIS3 phenotype, further extending the spectrum of abnormalities associated with GLIS3 mutations and providing novel insights into the role of GLIS3 in human physiological development. All but 2 of the patients within our cohort are still alive, and we describe the first patient to live to adulthood with a GLIS3 mutation, suggesting that even patients with a severe GLIS3 phenotype may have a longer life expectancy than originally described.

Dual-tubed multiplex-PCR for molecular characterization of carbapenemases isolated among Acinetobacter spp. and Pseudomonas spp

AIM

To molecularly characterize clinical isolates of Acinetobacter spp. and Pseudomonas spp. from various clinical samples so as to identify the carbapenemases mechanisms harboured by them.

MATERIALS AND RESULTS

A total of 95 carbapenem-resistant, nonduplicate, multi-drug resistant Gram-negative clinical isolates (53 Acinetobacter spp. and 42 Pseudomonas spp.), were collected between July and December 2012. Modified Hodge test (MHT) for the detection of carbapenemases was performed. Inhibitor-based test, EDTA for the detection of metallo-β-lactamases (MBL) and phenyl boronic acid (PBA) for the detection of Klebsiella pneumoniae carbapenemase (KPC), were performed to distinguish between different classes of β-lactamases. Two-tubed multiplex-PCR was performed for genotypic characterization of different classes of carbapenemases ((blaNDM-1 , blaOXA-48 like , blaKPC , blaVIM , blaIMP ), (blaOXA-23 like , blaOXA-24 like , blaOXA-51 like , blaOXA-58 like )). Eighty-five per cent (81/95) isolates were carbapenemase producers. Among these, 56.7% (44) were multiple carbapenemase producers. Furthermore, 48.14% (39) were MBLs, 35.8% (29) were carbapenem hydrolyzing class D β-lactamases (CHDLs), 16% (13) had MBLs as well as CHDLs and 14.7% (14/95) had none of the targeted resistance mechanisms. The overall rate of concordance between phenotypic and genotypic test was 97% and 98% for the detection of carbapenemases and MBL, respectively.

CONCLUSION

This is the first study from Western India which highlights the presence of multiple carbapenemases in nonfermenters Gram-negative bacilli (NFGNB). Co-existence of multiple carbapenemases along with other resistance mechanisms might result in treatment failure. Molecular characterization of the resistance mechanisms of suspected pathogens would help provide appropriate antimicrobial treatment for good clinical outcome.

SIGNIFICANCE AND IMPACT OF THE STUDY

Dual-tubed multiplex PCR decreases the time of amplification and thus the turnaround time which is crucial in clinical microbiology; this would be helpful in rapid characterization of CHDLs and MBLs.

Molecular characterization of carbapenem-resistant Enterobacteriaceae at a tertiary care laboratory in Mumbai

Carbapenem-hydrolyzing β-lactamases are increasingly reported worldwide, leading to therapeutic failure. In an era where the drug development pipeline is stagnant, it is crucial to preserve current classes of antibiotics to help fight against infection caused by multidrug-resistant organisms (MDROs), by practicing a rational approach for the use of antibiotics. Identifying the mechanisms of resistance gives us much needed insights in this field. A total of 113 consecutive, non-duplicate carbapenem-resistant clinical isolates were collected from July to December 2012. These isolates were subjected to the modified Hodge test (MHT) for phenotypic detection of carbapenemases, an inhibitor-based test employing EDTA for the detection of metallo-β-lactamase (MBL), and phenylboronic acid for the detection of Klebsiella pneumoniae carbapenemase (KPC). A multiplex polymerase chain reaction (PCR) assay that characterized the five most predominant carbapenemases (bla NDM, bla OXA, bla VIM, bla IMP, bla KPC) was designed. The 113 isolates consisted of Klebsiella spp. (46), Enterobacter spp. (32), Escherichia coli (31), Citrobacter spp. (2), Proteus spp. (1), and Morganella spp. (1). bla NDM-1 was the most prevalent carbapenemase and accounted for 75.22 % (85/113) of the isolates. This was followed by bla OXA [4.42 % (n = 5)]. 18.5 % (21/113) of the isolates possessed dual carbapenemase genes. 98.9 % concordance was observed between the phenotypic tests and the molecular tests for the detection of MBL. In conclusion, patients infected with resistant bacteria require early appropriate antimicrobial treatment for good clinical outcome. Thus, identifying the resistant mechanisms of suspected pathogens becomes crucial. Also, the high incidence of plasmid-mediated bla NDM-1 calls for the implementation of strict infection control and contact isolation precautions in order to prevent the spread of these organisms.