169. The Resurgence of Candida auris in California during the Novel Coronavirus (COVID-19) Pandemic, May 2020–May 2021

Background

In February 2019, California (CA) experienced its first C. auris outbreak in Orange County (OC). The CA Department of Public Health (CDPH) and OC with the Centers for Disease Control and Prevention (CDC), mounted a successful containment response; by November 2019, cases were limited to low-level spread in OC long-term acute care hospitals (LTACH).

In May 2020, C. auris cases began to surge in OC, followed by extensive spread in six other southern CA local health jurisdictions (LHJ). CDPH with LHJ and CDC, initiated an aggressive, interjurisdictional containment response.

Methods

We carried out response and preventive point prevalence surveys (PPS), onsite infection prevention and control (IPC) assessments, and in-service trainings at outbreak and interconnected hospitals and skilled nursing facilities in six LHJ. Other regional activities included: epidemiologic investigation, contact and discharge tracking and screening; increasing laboratory testing capacity; screening patients admitted to and from LTACH; statewide healthcare facility (HCF) education and outreach; sending regional outbreak HCF lists to all HCF; and biweekly state-LHJ coordination calls. The Antibiotic Resistance (AR) Lab Network supported testing.

Results

From May 2020—May 2021, we conducted screening at 226 HCF, and identified 1192 cases at 93 HCF, mostly through screening (n=1109, 93%) and at LTACH (n=906, 76%); we identified 113 (10%) cases at ACH, including 35 (31%) in COVID-19-burdened units. Cases peaked in August 2020 (n=93) and February 2021 (n=191) and have since declined, with C. auris resurgence mirroring COVID-19 incidence.

We conducted 98 onsite IPC assessments, and identified multiple, improper IPC practices which had been implemented in response to COVID-19, including double-gloving and -gowning, extended use of gowns and gloves outside patient rooms, and cohorting according to COVID-19 status only.

Figure 1. C. auris and COVID-19 Cases in California through May 2021, and C. auris Cases by Local Health Jurisdiction (LHJ) May 2020–May 2021

Table 1. By Facility Type: Colonization Testing May 2020–May 2021, and Total Case Counts before and from May 2020

Table 2. COVID-19-related Infection Control Practices Affecting C. auris Spread, and Associated Public Health Recommendations

Conclusion

The C. auris resurgence in CA was likely a result of COVID-19-related practices and conditions. An aggressive, coordinated, interjurisdictional C. auris containment response, including proactive prevention activities at HCF interconnected with outbreak HCF, can help mitigate spread of C. auris and potentially other novel AR pathogens.

Disclosures

All Authors: No reported disclosures

90. Impact of Infection Control Assessment and Response (ICAR) Visit on Candida auris Colonization Rates at Seven Long Term Acute Care Hospitals (LTACH) in Los Angeles County

Background

Public health authorities often use Infection Control Assessment and Response (ICAR) visits during Candida auris (C. auris) outbreak investigation to identify facility-level infection prevention and control (IPC) practice gaps and make recommendations to address those gaps. As an adjunct to ICAR visit, point prevalence surveys (PPS) provide an objective measure to determine if IPC recommendations are implemented. Because they require significant public health resources to perform, we evaluated the impact of ICAR visits on C. auris colonization rates.

Methods

PPS were conducted at seven long-term acute-care hospitals (LTACH) with C. auris outbreaks in Los Angeles County from July 2020 to May 2021. Skin swabs collected at PPS were tested for C. auris colonization by PCR technique. Pre-ICAR PPS results were compared with the average of two serial post-ICAR PPS results using repeated measures ANOVA test. Linear regression was used to estimate associations between individual ICAR domains and C. auris colonization.

Results

54 PPS were conducted at seven LTACHs with at least one ICAR visit made for every two PPS. On average, PPS were conducted 14 days (range 1-15 days) before and 10 days (range 4-33 days) after an ICAR visit. PPS positive rates with ICAR visit dates for each LTACH are shown in figure 1. Overall, ICAR visits were associated with a significant decrease (p=0.035) in the average of the positive rates in two serial post-ICAR PPS. When individual domain (hand hygiene, contact precautions, and environmental disinfection) of ICAR tool was analyzed, only adherence to environmental disinfection was significantly associated (p=0.038) with decrease in C. auris colonization rates. There was a moderate negative correlation (R2 = 0.26, β= -0.33) between environmental disinfection adherence and the magnitude of decrease in the colonization rates across all LTACHs (Figure 2).

Figure 1

Conclusion

ICAR visits were found to be significantly associated with a decrease in the average PPS positive rate on serial PPS. Parts of the ICAR tool that assessed environmental disinfection at the facility seemed most correlated with decrease in C. auris colonization rate. Streamlining the ICAR process to focus on the most impactful parts of ICAR tool may be a more efficient intervention to control C. auris outbreaks.

Disclosures

All Authors: No reported disclosures

Vestibular testing in children - The suppression head impulse (SHIMP) test

INTRODUCTION

The incidence of vestibular disorders and vertigo during childhood is increasing and pediatric clinicians have become more sensitive to children's balance disorders; thus, there is a need for appropriate detection test procedures for peripheral vestibular hypofunction. In order to ensure a reliable diagnosis and minimize misdiagnosis, a standardized clinical procedure via careful history and clinical examination is recommended. However, children, especially, are often unable to verbalize "vertigo" in a concrete manner, which often necessitates a consultation with a pediatrician holding nonspecific symptoms. The so-called suppression of the head impulse test (SHIMPs) represents a modification of the video head impulse test (HIMP) and is used for a more sensitive assessment of residual vestibular functions. In adults, SHIMPs are already an established diagnostic method. Nevertheless, to date, nothing is known about the applicability and standard values in childhood.

MATERIAL AND METHODS

In this monocentric, prospective study, we investigated whether SHIMPs enable a sensitive functional analysis of the vestibular system in healthy children of different ages. For this purpose, SHIMPs were performed in 40 children aged 3-18 years.

RESULTS

In this study, we demonstrated that SHIMPs can be easily performed in children (3-18 years). It is vital that the test be appropriately explained for children to ensure sufficient test tolerance and compliance.

CONCLUSION

SHIMPs are a helpful supplement to clinically established vestibular tests such as the HIMP in pediatric vestibular balance disorder diagnostics and can be integrated into the clinical routine, especially in children who have minimal verbal abilities or understanding of the instructions for HIMP. Similar to the HIMP, SHIMPs are characterized by a short test duration and a high tolerance.

Impact of COVID-19 on Pediatric Clinical Research

PURPOSE

Many public institutions and settings have taken action to limit exposure to and slow the spread of the novel coronavirus (COVID-19). We sought to characterize the impact of stay-at-home orders on our study of cerebral autoregulation and its association with developmental delays in infants with congenital heart disease compared with healthy controls.

DESIGN AND METHODS

We calculated the number of participants recruited (i.e., not enrolled in the study) and assessed (i.e., currently enrolled) before March 2020 (pre-COVID-19) and the number of participants that we could not recruit or assess between March and July 2020 (missed due to COVID-19), separately for congenital heart disease and healthy control infants, in reference to the impacts of COVID-19. We used negative binomial regressions to determine incidence rate ratios which compared participants recruited and assessed pre-COVID-19 and missed due to COVID-19.

RESULTS

Recruitment and assessments significantly decreased following the pandemic, i.e., participants were more likely to be recruited or be assessed pre-COVID-19 compared to during the pandemic. Study participants were 3.3 times as likely to have assessments performed pre-COVID-19 compared to during the COVID-19 pandemic (p < 0.001).

CLINICAL IMPLICATIONS

Clinical research teams may consider making protocol modifications such as virtual visits or video recordings explaining the study, for example, to adjust to the restrictions caused by COVID-19.

CONCLUSION

The COVID-19 pandemic drastically reduced recruitment and assessments completed in our study. Study teams will need to continue to modify procedures for recruitment and assessments that align with COVID-19 regulations to facilitate research progress during the pandemic.

Identifying microplastic litter with Laser Induced Breakdown Spectroscopy: A first approach

The broad diversity of microplastic litter requires a selection of analytical techniques to reliably determine the particle's chemical composition. This study demonstrates that Laser Induced Breakdown Spectroscopy (LIBS) can identify microplastic particles based on their spectral fingerprints. By studying the spectral features of polymer reference spectra, microplastic litter can be distinguished from non-plastic materials. The results show that LIBS can be used as a fast in-situ technique for pre-characterization of the microparticle's material and is a possible tool for environmental studies on microplastics.

Effects of SARS-CoV-2 on the Practice of Otolaryngology

OBJECTIVES

Otolaryngologists in Texas have been greatly affected by the coronavirus disease 2019 (COVID-19) pandemic. Executive orders and professional recommendations have changed the way otolaryngologists practice. The objective of the study was to determine the effect of COVID-19 on otolaryngologists in the state of Texas.

METHODS

We surveyed the Texas Association of Otolaryngology to evaluate burnout, research output, and ability to respond to the pandemic. We also looked at the effect of Texas governmental executive orders GA-09 and GA-15 on work hours and patient load.

RESULTS

Our survey showed no significant difference in personnel contracting COVID-19 with perception of adequate personal protective equipment (P = 0.203), population density (P = 0.445), or type of practice (P = 0.763). The phenomenon of "pandemic burnout" was prevalent, with prolonged uncertainty the primary contributing factor for burnout caused by the pandemic.

CONCLUSIONS

The response to COVID-19 and the course of the pandemic are continuing to evolve and may play a significant role in how otolaryngologists practice and on their well-being during the pandemic.

Findings and Resolution of Melanoma Perineural Spread Along the Greater Auricular Nerve on FDG PET/CT and MRI

ABSTRACT

We report an unusual case of a 59-year-old man with recurrent right ear melanoma resulting in perineural spread to the right greater auricular nerve. Direct perineural spread to the greater auricular nerve is not commonly reported in melanoma. Our case demonstrates perineural spread along the greater auricular nerve on 18F-FDG PET/CT and MRI. This finding was supported by intraneural invasion noted at the surgical margin of the wide local excision of the right helix melanoma. Resolution of FDG activity and improved MRI appearances of the right greater auricular nerve were seen after immunotherapy treatment.

Antidiuretic hormone inhibits osteogenic differentiation of dental follicle stem cells via V1a receptors and the PLC-IP3 pathway

OBJECTIVE

The aim of this study was to elucidate the molecular mechanism by which antidiuretic hormone (ADH) inhibited osteogenesis in dental follicle stem cells.

DESIGN

Rat dental follicle stem cells were cultured in osteogenic differentiation medium supplemented with ADH. Alkaline phosphatase enzyme activity, Alizarin Red S staining, MTT assay and RT-qPCR was used to examine ADH's impact on cell mineralization, viability, and osteogenic gene expression. Real-time calcium imaging analysis was performed to identify the ADH receptor and its mechanism of action.

RESULTS

ADH supplementation to the osteogenic differentiation medium inhibited cell mineralization without compromising cell viability and downregulated the expression of key osteogenic genes: DCN (Decorin), RUNX2 (Runt-related transcription factor 2) and BSP (Bone sialoprotein). Real-time calcium imaging analysis revealed that ADH (1-1000 nM) increased intracellular calcium in a concentration-dependent manner. Pretreatment of cells with V2255, a V1a receptor blocker, inhibited the calcium signals, but not with the V1b (Nelivaptan) or V2 (Tolvaptan). V2255 also reversed the inhibitory effect of ADH on osteogenesis. Furthermore, U73122, a Phospholipase C (PLC) inhibitor, 2-APB, an Inositol Triphosphate (IP₃) receptor blocker, and depletion of endoplasmic reticulum calcium stores abolished the calcium signals by ADH.

CONCLUSIONS

Our results demonstrated that ADH activates V1a receptors and the PLC-IP₃ pathway to stimulate intracellular calcium signals, which inhibits cell mineralization and osteogenic gene expression. These findings uncovered a novel function for ADH as a negative regulator of osteogenesis in dental follicle stem cells. The role of ADH in the pathogenesis of bone diseases remains to be determined.

Early versus late tube feeding initiation after PEG tube placement: Does time to feeding matter?

BACKGROUND

Variation exists in the timing of tube feed initiation after percutaneous endoscopic gastrostomy (PEG) tube placement. The aim of our study was to review outcomes of early tube feed (ETF) versus late tube feed (LTF) initiation after PEG tube placement.

METHODS

We performed a retrospective review of all trauma patients who underwent PEG tube placement from 1/2014 to 12/2018. ETF was defined as initiation < 24 h and LTF > 24 h after placement. The primary outcome measure was feeding intolerance and secondary outcomes included post-operative complications. All statistical analyses were performed using standard statistical methods (e.g. Pearson's Chi-squared, Fisher's exact and Mann Whitney-U tests).

RESULTS

There were 295 patients (164 ETF and 131 LTF) that received a PEG tube at our level 1 trauma center. There was no difference with feeding intolerance at 12 h (5% vs. 4%; p = 0.88), 24 h (1% vs. 2%; p = 1.00), and 48 h (4% vs. 4%; p = 1.00). There was no difference when comparing intolerance symptoms such as nausea and vomiting (1% vs. 2%; p = 0.79), abdominal tenderness (2% vs. 3%; p = 0.76), high gastric residuals (2% vs. 2%; p = 1.00) and aspiration (0% vs. 2%; p = 0.39). There was no difference when comparing post-operative complications (4% vs. 8%; p = 0.21).

CONCLUSIONS

Early tube feeding after PEG placement is safe and equivalent to late tube feeding in the adult trauma population. Future prospective studies are warranted to establish the optimal timing for initiation of tube feeds after PEG tube placement.

Diagnostic tools used for melanoma: A survey of Australian general practitioners and dermatologists

BACKGROUND/OBJECTIVE

Diagnostic tools such as dermoscopy, sequential digital dermoscopy imaging (SDDI), total body photography (TBP) and automated diagnostic tools are available to assist in early melanoma diagnosis. The use, accessibility and barriers of dermoscopy have been well studied; however, there are few similar studies regarding SDDI, TBP and automated diagnostic tools. We aim to understand the use of these diagnostic aids amongst Australian general practitioners (GPs) and dermatologists.

METHODS

Between June 2019 and January 2020, GPs and dermatologists across Australia were invited to participate in an online survey. Surveys were distributed through GP and dermatology organisations.

RESULTS

A total of 227 survey responses were received, 175 from GPs and 52 from dermatologists. Amongst GPs, 44.6% worked in a skin cancer clinic. Dermoscopy was used at least occasionally by 98.9% of all GPs. SDDI was used by 93.6% of skin cancer GPs, 80.8% of dermatologists and 45.3% of generalist GPs. TBP was used or recommended by 77.1% of generalist GPs, 82.3% of skin cancer GPs and 86.5% of dermatologists. The most common barriers to the use of TBP were cost, limited accessibility, poor patient compliance, and time required for both patients and doctors. Very few clinicians reported using automated diagnostic tools. There was an interest in future diagnostic aids for melanoma in 88% of GPs and dermatologists.

CONCLUSION

Dermoscopy, SDDI and TBP were commonly used by responding Australian skin cancer GPs and dermatologists in this survey. Automated diagnostic tools were not reported to be used routinely. Several barriers were identified for use of TBP.

Reconnaissance of tumor immune microenvironment spatial heterogeneity in metastatic renal cell carcinoma and correlation with immunotherapy response

A clearer understanding of the tumor immune microenvironment (TIME) in metastatic clear cell renal cell carcinoma (ccRCC) may help to inform precision treatment strategies. We sought to identify clinically meaningful TIME signatures in ccRCC. We studied tumors from 39 patients with metastatic ccRCC using quantitative multiplexed immunofluorescence and relevant immune marker panels. Cell densities were analyzed in three regions of interest (ROIs): tumor core, tumor-stroma interface and stroma. Patients were stratified into low- and high-marker density groups using median values as thresholds. Log-rank and Cox regression analyses while controlling for clinical variables were used to compare survival outcomes to patterns of immune cell distributions. There were significant associations with increased macrophage (CD68⁺ CD163⁺ CD206⁺ ) density and poor outcomes across multiple ROIs in primary and metastatic tumors. In primary tumors, T-bet⁺ T helper type 1 (Th1) cell density was highest at the tumor-stromal interface (P = 0·0021), and increased co-expression of CD3 and T-bet was associated with improved overall survival (P = 0·015) and survival after immunotherapy (P = 0·014). In metastatic tumor samples, decreased forkhead box protein 3 (FoxP3)⁺ T regulatory cell density correlated with improved survival after immunotherapy (P = 0·016). Increased macrophage markers and decreased Th1 T cell markers within the TIME correlated with poor overall survival and treatment outcomes. Immune markers such as FoxP3 showed consistent levels across the TIME, whereas others, such as T-bet, demonstrated significant variance across the distinct ROIs. These findings suggest that TIME profiling outside the tumor core may identify clinically relevant associations for patients with metastatic ccRCC.

A Mouse Model to Investigate the Role of Cancer-associated Fibroblasts in Tumor Growth

Cancer-associated fibroblasts (CAFs) can play an important role in tumor growth by creating a tumor-promoting microenvironment. Models to study the role of CAFs in the tumor microenvironment can be helpful for understanding the functional importance of fibroblasts, fibroblasts from different tissues, and specific genetic factors in fibroblasts. Mouse models are essential for understanding the contributors to tumor growth and progression in an in vivo context. Here, a protocol in which cancer cells are mixed with fibroblasts and introduced into mice to develop tumors is provided. Tumor sizes over time and final tumor weights are determined and compared among groups. The protocol described can provide more insight into the functional role of CAFs in tumor growth and progression.

Utility of nuclear stress imaging in predicting long-term outcomes one-year post CABG Surgery

BACKGROUND

Early MPI after CABG is currently considered rarely appropriate in asymptomatic patients. This study aimed to identify prognostic value of nuclear stress-imaging post-CABG.

METHODS

This was a single center prospective study looking at long-term outcomes post-CABG. Per protocol participants underwent SPECT-MPI stress testing and coronary angiogram on the same day, 1-year following CABG. Defect size was semi-quantified. The primary outcomes were the composite of death and congestive heart failure.

RESULTS

Eighty-four participants underwent nuclear stress-imaging and angiography, with a median follow-up of 11.1 years. Three separate stress findings predicted the primary outcome: inability to reach stage 3 of a Bruce protocol (OR 7.3, CI 2.4-22.1, P < 0.001), LVEF < 45% (OR 4.0, CI 1.1-15.3, P = 0.041) and a moderate-large stress defect size (HR 2.31, CI 1.1-1.5, P = 0.04). These findings appear to be additive and strongest among patients who underwent exercise stress testing (HR 10.6, CI 3.6-30.6, P < 0.001). Graft disease was identified in 39 (46%) patients and compared to those individuals with no graft disease, did not predict long-term adverse outcomes (P = 0.29).

CONCLUSION

In clinically stable patients early after revascularization with CABG, SPECT-MPI can identify patients at higher risk of heart failure and death.

Effect of oral tranexamic acid on erythema index in patients with melasma

Melasma is a common disorder of hyperpigmentation that presents a therapeutic challenge for clinical dermatologists. The pathogenesis is complex, but previous studies have demonstrated vascular proliferation is a key factor in the development of the classic hyperpigmented patches. Studies have revealed reduction of erythema by oral tranexamic acid; however, there has been no direct comparison to placebo. This 24-week randomised placebo-controlled trial demonstrates oral tranexamic acid may improve erythema in melasma. This mechanism of action may be the reason for the success of tranexamic acid in complex and difficult to treat melasma.

Hirschsprung’s Disease: Two Cases of Total Intestinal Aganglionosis

Introduction/Objective

Hirschsprung’s disease is a disorder associated with an absence of ganglion cells in a segment of the bowel. Total colonic and small bowel aganglionosis occurs in less than 1% of all Hirschsprung’s disease patients. Even rarer is the finding of Haddad syndrome, the coexistence of congenital central hypoventilation syndrome and Hirschsprung’s disease. Congenital central hypoventilation syndrome has approximately 1,000 reported cases, with colonic aganglionosis being associated with 15-20% of those cases. The prevalence of Hirschsprung’s disease with congenital renal anomalies may be another underreported finding.

Methods

Here, we report two rare cases of Hirschsprung’s disease with significant extension in the small bowel. One case involves a 38-week gestational age male infant admitted for apnea and another case involves 39-week gestational age female infant admitted for vomiting.

Results

Both infants had rectal suction biopsies confirming the absence of ganglion cells. The male infant had mapping biopsies which histologically showed hypertrophic nerve fibers and an absence of ganglion cells in the colon extending up to 70 cm proximal to the ileocecal valve. Calretinin immunostaining confirmed aganglionsis. Genetic testing showed a PHOX2B gene mutation carrying 32 polyalanine repeat mutations, confirming a diagnosis of congenital central hypoventilation syndrome coexisting with Hirschsprung’s disease. The female infant had intraoperative frozen sections that identified ganglion cells throughout the colon. On permanent sections, there was an absence of ganglion cells in the upper rectum extending up to 65 cm proximal to the ileocecal valve. She also was noted to have agenesis of the left kidney and a urachal remnant. Genetic testing was negative for RET mutations.

Conclusion

Overall, these cases provide further information on a rare variant of Hirschsprung’s disease that includes significant portions of the small bowel. Additionally, this study adds to the documented reports of Haddad syndrome and the connections between renal anomalies with Hirschsprung’s disease. Last, this series alludes to the difficulties of frozen section diagnosis of this disease.

Pharmacogenomics in Asian Subpopulations and Impacts on Commonly Prescribed Medications

Asians as a group comprise > 60% the world's population. There is an incredible amount of diversity in Asian and admixed populations that has not been addressed in a pharmacogenetic context. The known pharmacogenetic differences in Asian subgroups generally represent previously known variants that are present at much lower or higher frequencies in Asians compared with other populations. In this review we summarize the main drugs and known genes that appear to have differences in their pharmacogenetic properties in certain Asian populations. Evidence-based guidelines and summary statistics from the US Food and Drug Administration and the Clinical Pharmacogenetics Implementation Consortium were analyzed for ethnic differences in outcomes. Implicated drugs included commonly prescribed drugs such as warfarin, clopidogrel, carbamazepine, and allopurinol. The majority of these associations are due to Asians more commonly being poor metabolizers of cytochrome P450 (CYP) 2C19 and carriers of the human leukocyte antigen (HLA)-B*15:02 allele. The relative risk increase was shown to vary between genes and drugs, but could be > 100-fold higher in Asians. Specifically, there was a 172-fold increased risk of Stevens-Johnson syndrome and toxic epidermal necrolysis with carbamazepine use among HLA-B*15:02 carriers. The effects ranged from relatively benign reactions such as reduced drug efficacy to severe cutaneous skin reactions. These reactions are severe and prevalent enough to warrant pharmacogenetic testing and appropriate changes in dose and medication choice for at-risk populations. Further studies should be done on Asian cohorts to more fully understand pharmacogenetic variants in these populations and to clarify how such differences may influence drug response.