Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2024 Update by the Infectious Diseases Society of America (IDSA) and the American Society for Microbiology (ASM).

The critical nature of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician and the microbiologists who provide enormous value to the health care team. This document, developed by experts in both adult and pediatric laboratory and clinical medicine, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. Sections are divided into anatomic systems, including Bloodstream Infections and Infections of the Cardiovascular System, Central Nervous System Infections, Ocular Infections, Soft Tissue Infections of the Head and Neck, Upper Respiratory Infections, Lower Respiratory Tract infections, Infections of the Gastrointestinal Tract, Intraabdominal Infections, Bone and Joint Infections, Urinary Tract Infections, Genital Infections, and Skin and Soft Tissue Infections; or into etiologic agent groups, including arboviral Infections, Viral Syndromes, and Blood and Tissue Parasite Infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. In addition, the pediatric needs of specimen management are also addressed. There is redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a reference to guide physicians in choosing tests that will aid them to diagnose infectious diseases in their patients.

The American Association of Latino Orthopaedic Surgeons: Our History, Achievements, and Future Goals.

ABSTRACT: The mission of the American Association of Latino Orthopaedic Surgeons (AALOS) is to provide collegiality, advancement, education, and social justice for Latino orthopaedic surgeons and the minority populations they represent. We strive to enhance diversity within the field of orthopaedic surgery by increasing the visibility of AALOS, highlighting its core focus, and emphasizing its mission. The purposes of this article are to discuss the need for this organization and highlight its history and future goals. As AALOS recently celebrated its 15-year anniversary, we are excited to continue advancing the field of orthopaedic surgery and improving our patients' care.

Be a Lighthouse for Your Medical Students: How to Help Them Navigate During Changing Times to a Successful Match.

The transition between medical school and residency is a complex, multifaceted process that is commonly a time of stress and uncertainty for medical students. Occupying most of a student's final year of medical school, the residency application includes a primary Electronic Residency Application Service application, a variable number of program-specific secondary applications, and interviews. The application process culminates with The Match. Orthopaedic surgery is among the more competitive specialties; thus, it is critical that all involved parties understand the complexity of the process and the numerous variables that play into such a critical decision point in the career trajectory of a future physician. It is important to provide a mentor with an overview of the residency application process, specifically with respect to orthopaedic surgery, so that they may be best prepared to guide their medical student mentee through the process and help them find success.

Advising Orthopaedic Hopefuls in the Wake of a Pass/Fail US Medical Licensing Examination Step 1: A Proposed Method for Predicting US Medical Licensing Examination Step 2 Clinical Knowledge Outcomes.

INTRODUCTION: Matching into orthopaedic residency has become difficult, and the US Medical Licensing Examination Step 1 transition to pass/fail scoring has complicated the process. Advisors' ability to mentor students has decreased, and program directors may rely on Step 2 Clinical Knowledge (CK) scores in selecting which candidates to interview. This study aims to offer a method to predict Step 2 CK outcomes based on preadmission and preclinical performance. METHODS: The study investigated 486 students from a US medical school who enrolled in 2017 and 2018. Data on demographics, preadmission, and preclinical performance were collected. Before model creation, it was found that sex, Medical College Admission Test scores, Comprehensive Basic Science Examination performance, and preclinical curriculum performance produced optimal models. Multivariate ordinal logistic regression models were built to predict probabilities of four outcome levels of Step 2 CK: <235, 235 to 249, 250 to 265, and >265. Finally, nomograms were created to visualize probability calculations. RESULTS: Each model's odds ratios revealed that female sex, higher MCAT scores, and better Comprehensive Basic Science Examination and preclinical performance were associated with an increased likelihood of being in higher Step 2 CK scoring groups. Preclinical performance had a profound effect, especially for those in the top 1/3. Models were successful in assigning higher probabilities to students in higher Step 2 CK scoring groups in more than 80% of instances. Nomograms presented provide examples of how to apply these models to an individual student. DISCUSSION: This study presents a novel method for predicting probabilities of Step 2 CK outcomes that can be used to mentor students at a time point when Step 1 previously filled this role. It may assist in identifying orthopaedic hopefuls at risk of performing poorly on Step 2 CK and can foster the development of individualized guidance and mitigation strategies.

Respiratory Coinfections in Children With SARS-CoV-2.

BACKGROUND: As the transmission of endemic respiratory pathogens returns to prepandemic levels, understanding the epidemiology of respiratory coinfections in children with SARS-CoV-2 is of increasing importance. METHODS: We performed a retrospective analysis of all pediatric patients 0-21 years of age who had a multiplexed BioFire Respiratory Panel 2.1 test performed at Children's Healthcare of Atlanta, Georgia, from January 1 to December 31, 2021. We determined the proportion of patients with and without SARS-CoV-2 who had respiratory coinfections and performed Poisson regression to determine the likelihood of coinfection and its association with patient age. RESULTS: Of 19,199 respiratory panel tests performed, 1466 (7.64%) were positive for SARS-CoV-2, of which 348 (23.74%) also had coinfection with another pathogen. The most common coinfection was rhino/enterovirus (n = 230, 15.69%), followed by adenovirus (n = 62, 4.23%), and RSV (n = 45, 3.507%). Coinfections with SARS-CoV-2 were most commonly observed in the era of Delta (B.1.617.2) predominance (190, 54.60%), which coincided with periods of peak rhino/enterovirus and RSV transmission. Although coinfections were common among all respiratory pathogens, they were significantly less common with SARS-CoV-2 than other pathogens, with exception of influenza A and B. Children <2 years of age had the highest frequency of coinfection and of detection of any pathogen, including SARS-CoV-2. Among children with SARS-CoV-2, for every 1-year increase in age, the rate of coinfections decreased by 8% (95% CI, 6-9). CONCLUSIONS: Respiratory coinfections were common in children with SARS-CoV-2. Factors associated with the specific pathogen, host, and time period influenced the likelihood of coinfection.

Vulvovaginal Symptoms in a Postmenopausal Woman: A Case Study.

A postmenopausal female patient was suffering from vulvovaginal symptoms such as dryness and irritation, which were affecting her relationship with her partner and her overall quality of life. The patient was instructed to apply an estriol 0.1% vaginal ointment (PCCA Ellage Anhydrous Vaginal) for a duration of three months. The safety and efficacy of the compounded treatment were evaluated using an online data collection form, which included the validated Vulvovaginal Symptom Questionnaire. Post-treatment results show that the vulvovaginal symptoms were no longer bothersome, and that the patient's relationship was no longer affected. There were no reports of undesirable effects as a result of the compounded treatment. This case study reinforces the benefits and convenience of using topical hormone replacement therapy in postmenopausal women.

Building Blocks of Wellness: Where Do We Start When Our Tasks Have No End?

Surgeon wellness, and the means by which it may be realized, has recently come to the forefront as awareness of burnout among orthopaedic surgeons has increased. Individual surgeons face unique challenges toward finding their own path to thrive. It is important to incorporate varying perspectives regarding potential solutions to surgeons' stresses in both work and extracurricular life. Specifically, the goal is to initiate a discussion regarding wellness by providing insight into the challenges facing surgical residents, supplemented with the perspectives of women and minorities within the field. Peer coaching plays an essential role in optimizing mental health.

Nerve Compression Syndromes of the Upper Extremity.

Nerve compression syndromes of the upper extremity are among the most common pathologies encountered in orthopaedic surgery. Symptoms can be debilitating for patients-affecting their work, activity level, sleep patterns, and overall quality of life. The community orthopaedic specialist should be familiar with the anatomy, etiology, and presentation of upper extremity nerve entrapment. Furthermore, knowledge of current evidence surrounding the management of these common syndromes can prove valuable for treating clinicians. Treatment ranges from nonsurgical (including medication and splinting) to surgical (when symptoms are severe). Although the gold standard treatment for nerve compression syndromes of the upper extremity is typically surgical release, nonsurgical methods should also be reviewed and understood because these can play an important role for patients as well. Community orthopaedic specialists should be well aware of the risks and complications associated with surgical releases.

The Interaction of Diabetic Peripheral Neuropathy and Carpal Tunnel Syndrome.

BACKGROUND: Diabetes mellitus (DM) increases the risk for carpal tunnel syndrome (CTS) and is associated with its own neuropathic complications. Diabetic peripheral neuropathy (DPN) is a common complication seen in diabetic patients. In this study, we examine the relationship between the severity of DPN and CTS. METHODS: Type 2 diabetic and control patients (n = 292) were recruited at a clinic visit. The Michigan Neuropathy Screening Instrument (MNSI) questionnaire was used to collect data related to peripheral neuropathy. The MNSI scores were compared for patients with CTS with and without DM in univariable and multivariable analyses. χ2 analyses were performed to quantitatively measure the associations between peripheral neuropathy and the presence of CTS. RESULTS: Of the 292 patients, 41 had CTS, and 19 of these had both CTS and DM. Of the 138 diabetic patients, 85 had peripheral neuropathy. There was no association between a diagnosis of CTS and an MNSI score indicative of peripheral neuropathy. In the diabetic population, CTS was inversely associated with DPN (P = .017). The MNSI scores between diabetic and control patients with CTS were comparable. CONCLUSION: The severity of peripheral neuropathy in diabetic patients with and without CTS is comparable. Diabetic patients without peripheral neuropathy have an association with higher incidence of CTS in this study, suggesting that there are disparate mechanisms causing DPN and CTS. Nevertheless, diabetes and CTS are risk factors for developing the other, and future studies should further explore how DPN and CTS differ to tailor patient interventions based on their comorbidities.

Do Intra-articular Corticosteroid Injections Prior to Total Knee Arthroplasty Increase Postoperative Complication Rates: A Retrospective Review.

There is conflicting literature suggesting that intra-articular corticosteroid injections before total knee arthroplasty (TKA) may lead to an increase in the rate of postoperative complications, specifically periprosthetic joint infection (PJI). Thus, this retrospective review of all TKAs performed at a large, urban hospital will add valuable evidence to help guide future patient care. After exclusion criteria, we retrospectively reviewed 417 patients who received a TKA from a group of fellowship-trained orthopaedic surgeons between 2009 and 2016 at a single academic medical center. Minimum follow-up time was 1 year. Patients were separated into two groups: those who received a preoperative intra-articular corticosteroid injection and those who did not receive an injection. Subgroups were created based on the timing of their most recent preoperative injection: 0 to 3 months, 3 to 6 months, 6 to 12 months, 12+ months, and an unknown time period. Postoperative outcomes for PJI, revision TKA, and manipulation under anesthesia (MUA) were analyzed via a Chi-square test. No statistically significant postoperative differences were observed between groups: PJI (p = 0.904), revision TKA (p = 0.206), and MUA (p = 0.163). The temporal subgroups also failed to demonstrate a statistically significant result: PJI (p = 0.348), revision TKA (p = 0.701), and MUA (p = 0.512). This study revealed no absolute or temporal association between preoperative, intra-articular corticosteroid injections, and complications after TKA. Because these injections are a commonly used treatment modality prior to TKA, further studies should be conducted on a nationwide basis to draw more concrete conclusions.

Hand size affects branching of the deep ulnar nerve and deep palmar arch.

PURPOSE: Understanding the anatomy of the deep neurovascular structures of the hand is essential in surgical planning. There is a lack of literature regarding hand size and its influence in branching variation and the distances between branches of various neurovascular structures. Our study quantifies the variation in branching distances of the deep ulnar nerve and deep palmar arch branches. METHODS: Twenty-five fresh-frozen cadaveric hands were dissected. Each branch of the deep ulnar nerve and deep palmar arch was identified. The distance from the most distal portion of the pisiform to the proximal aspect of the branch was measured. The relationship between the length of the third metacarpal and the distance of each branch from the pisiform was examined. RESULTS: There was no relationship between branching differences in the deep ulnar nerve and the length of the third metacarpal. There was a significant association between the length of the third metacarpal and the second, third, and fourth branches of the deep palmar arch (p < 0.05). CONCLUSIONS: Our study found a significant association between the branching distances of the second, third, and fourth branches of the deep palmar arch and hand size as measured by the length of the third metacarpal.

Management and Outcomes of Salmonella Gastroenteritis in the Era of Rapid Molecular Testing.

BACKGROUND AND OBJECTIVES: Molecular diagnostics provide a rapid and sensitive diagnosis of gastroenteritis compared with a stool culture. In this study, we seek to describe the changes in medical management and outcomes of children with Salmonella gastroenteritis as our hospital system adopted molecular diagnostics. METHODS: This study is a retrospective chart review of children <18 years of age diagnosed with nontyphoidal Salmonella gastroenteritis between 2008 and 2018 at a large pediatric health care system in the southeastern United States. Those with immunocompromising conditions and hemoglobinopathies were excluded. Patients diagnosed via molecular testing were compared with those diagnosed solely by stool culture for aspects of management including admission rates, blood culture obtainment, and antibiotic administration. RESULTS: Of 965 eligible patients with Salmonella gastroenteritis, 264 (27%) had a stool molecular test and 701 (73%) only had a stool culture performed. Groups were similar in age and presentation. Those diagnosed by molecular methods had higher hospitalization rates (69% vs 50%, P <.001), more blood cultures obtained (54% vs 44%, P <.01), and received more antibiotics (49% vs 34%, P <.001) despite statistically similar rates of bacteremia (11% vs 19%, P = .05). CONCLUSIONS: The rapid diagnosis of Salmonella gastroenteritis by molecular methods was associated with increased hospital admission rates, blood culture obtainment, and antibiotic use. This suggests possible overmedicalization of uncomplicated Salmonella gastroenteritis, and clinicians should remain cognizant of the possibility of providing low-value care for uncomplicated disease.

Cat Scratch Disease: 9 Years of Experience at a Pediatric Center.

Background: A more complete understanding of the epidemiology, risk factors, and clinical features of cat scratch disease (CSD) in children could help guide patient care. Methods: We conducted a retrospective analysis of children presenting to a tertiary pediatric hospital system in Atlanta, Georgia between January 1, 2010 and December 31, 2018 who had serology, polymerase chain reaction, and/or cytopathological results consistent with a Bartonella henselae infection. We also retrospectively reviewed veterinary diagnostic results performed at the University of Georgia from 2018 to 2020 to ascertain the burden of bartonellosis in companion animals within the state. Results: We identified 304 children with CSD over 9 years with the largest proportion of diagnoses made during August (41 of 304, 13.5%) and September (47 of 304, 15.5%). The median age of child cases was 8.1 years (interquartile range [IQR], 5.4-12.1); 156 (51.3%) were female; 242 of 262 (92.4%) reported feline exposure; and 55 of 250 (22%) reported canine exposure of those with exposure histories documented in the medical record. Although lymphadenopathy was present on physical examination in the majority of cases (78.8%), atypical presentations lacking lymphadenopathy were also common (63 of 304, 20.7%). Among children with radiographic imaging, 20 of 55 (36.4%) had splenomegaly and 21 of 55 (38.1%) had splenic and/or hepatic microabscesses. Among veterinary data, Bartonella seroprevalence was 12 of 146 (8.2%), all among canines, with a geographic distribution that spanned the state of Georgia. Conclusions: Distinguishing clinical features of CSD included subacute regional lymphadenopathy in school-aged children in the late summer, almost all of whom had cat exposure. Atypical clinical manifestations of CSD were also commonly identified.

Increased Rate of Fracture Injuries Associated With Alternative Modes of Transportation During COVID-19.

OBJECTIVE: COVID-19 disrupted public transit and led to increased reliance on alternative modes of transportation (AMTs) internationally. This study hypothesizes that public interest and fracture injuries associated with AMTs increased during COVID-19 in the United States. METHODS: Monthly Google search probabilities and the number of fracture injuries associated with bicycles, scooters, skateboards/longboards, rollerblades, electric bicycles, and electric micromobility vehicles were collected from January 2017 to December 2021. Wilcoxon signed-rank tests were used to assess differences in search probabilities and fracture injuries between 2021, 2020, and 2019. Linear regression was used to study the relationship between search probabilities and number of fracture injuries. RESULTS: For bicycles, skateboards/longboards, electric bicycles, and electric micromobility vehicles, search probabilities and fracture injuries were higher in 2021 and 2020 compared with 2019, except for bicycle fractures in 2021 (P < 0.05). For every AMT, except roller skates, search probability had an explanatory effect on fracture injuries (P < 0.001). CONCLUSION: Online interest in AMTs and associated fracture injuries increased during the COVID-19 pandemic. Excess fractures seem to be stabilizing as of December 2021, but online search volumes may be used to inform the allocation of orthopaedic trauma resources during future surges in COVID-19 and other epidemics.

Effects of pelvic obliquity and limb position on radiographic leg length discrepancy measurement: a Sawbones model.

PURPOSE: Potential sources of inaccuracy in leg length discrepancy (LLD) measurements commonly arise due to postural malalignment during radiograph acquisition. Preoperative planning techniques for total hip arthroplasty (THA) are particularly susceptible to this inaccuracy, as they often rely solely on radiographic assessments. Owing to the extensive variety of pathologies that are associated with LLD, an understanding of the influence of malpositioning on LLD measurement is crucial. In the present study, we sought to characterize the effects of varying degrees of lateral pelvic obliquity (PO) and mediolateral limb movement in the coronal plane on LLD measurement error (ME). METHODS: A 3-D sawbones model of the pelvis with bilateral femurs of equal-length was assembled. Anteroposterior pelvic radiographs were captured at various levels of PO: 0°, 5°, 10°, and 15°. At each level of PO, femurs were individually rotated medio-laterally to produce 0°, 5°, 10°, and 15° of abduction/adduction. LLD was measured radiographically at each position combination. For all cases of PO, the right-side of the pelvis was designated as the higher-side, and the left as the lower-side. RESULTS: At 0° PO, 71% of tested variations in femoral abduction/adduction resulted in LLD ME < 0.5-cm, while 29% were ≥ 0.5-cm, but < 1-cm. ME increased progressively as one limb was further abducted while the contralateral limb was simultaneously further adducted. The highest ME occurred with one femur abducted 15° and the other adducted 15°. Similar magnitudes of ME were seen in 98% of tested femoral positions at 5° of PO. The greatest ME (~ 1 cm) occurred at the extremes of right-femur abduction and left-femur adduction. At 10° of PO, a higher prevalence of cases exhibited LLD ME > 0.5-cm (39%) and ≥ 1-cm (8%). The greatest errors occurred at femoral positions similar to those seen at 5° of PO. At 15° of PO, half of tested variations in femoral position resulted in LLD ME > 1-cm, while 22% of cases produced errors > 1.5-cm. These clinically significant errors occurred at all tested variations of right-femur abduction, with the left-femur in either neutral position, abduction, or adduction. CONCLUSION: This study aids surgeons in understanding the magnitude of radiographic LLD ME produced by varying degrees of PO and femoral abduction/adduction. At a PO of ≤5°, variations in femoral abduction/adduction of up to 15° produce errors of marginal clinical significance. At PO of 10° or 15°, even small changes in mediolateral limb position led to clinically significant ME (> 1-cm). This study also highlights the importance of proper patient positioning during radiograph acquisition, demonstrating the need for surgeons to assess the quality of their radiographs before performing preoperative templating for THA, and accounting for PO (> 5°) when considering the validity of LLD measurements.

Croup Associated With SARS-CoV-2: Pediatric Laryngotracheitis During the Omicron Surge.

In this retrospective analysis, we describe weekly croup and corresponding viral prevalence patterns in a pediatric quaternary care system in metropolitan Atlanta. We characterize a series of 24 patients with croup associated with SARS-CoV-2 infection and show that this clinical presentation increased substantially in frequency during the period of high Omicron vs Delta transmission.

Comparison of Mid-turbinate Nasal Swabs, Saliva, and Nasopharyngeal Swabs for SARS-CoV-2 Reverse Transcription-Polymerase Chain Reaction Testing in Pediatric Outpatients.

CONTEXT.­: Diagnostic testing for SARS-CoV-2 in symptomatic and asymptomatic children remains integral to care, particularly for supporting return to and attendance in schools. The concordance of SARS-CoV-2 detection in children, using various specimen types, has not been widely studied. OBJECTIVE.­: To compare 3 sample types for SARS-CoV-2 polymerase chain reaction (PCR) testing in children, collected and tested at a single facility. DESIGN.­: We prospectively recruited 142 symptomatic and asymptomatic children/young adults into a sample comparison study performed in a single health care system. Each child provided self-collected saliva, and a trained health care provider collected a mid-turbinate nasal swab and nasopharyngeal (NP) swab. Specimens were assayed within 24 hours of collection by using reverse transcription-polymerase chain reaction (RT-PCR) to detect SARS-CoV-2 on a single testing platform. RESULTS.­: Concurrently collected saliva and mid-turbinate swabs had greater than 95% positive agreement with NP swabs when obtained within 10 days of symptom onset. Positive agreement of saliva and mid-turbinate samples collected from children with symptom onset >10 days prior, or without symptoms, was 82% compared to NP swab samples. Cycle threshold (Ct) values for mid-turbinate nasal samples more closely correlated with Ct values from NP samples than from saliva samples. CONCLUSIONS.­: These findings suggest that all 3 sample types from children are useful for SARS-CoV-2 diagnostic testing by RT-PCR, and that concordance is greatest when the child has had symptoms of COVID-19 within the past 10 days. This study provides scientific justification for using sample types other than the NP swab for SARS-CoV-2 testing in pediatric populations.

Compound Motor Action Potentials During a Modest Nerve Crush.

Nerve crush injury results in axonotmesis, characterized by disruption of axons and their myelin sheaths with relative sparing of the nerve's connective tissue. Despite the widespread use of crush injury models, no standardized method for producing these lesions has been established. We characterize a crush model in which a narrow forceps is used to induce a modest and controlled compressive injury. The instantaneous compound motor action potential (CMAP) is monitored in situ and in real-time, allowing the characterization of neuromuscular response during and after injury. The tibial nerves of 11 anesthetized rats were surgically isolated. After the placement of electrodes, CMAPs were elicited and registered using a modular-data-acquisition system. Dumont-#5 micro-forceps were instrumented with a force transducer allowing force measurement via a digital sensor. Baseline CMAPs were recorded prior to crush and continued for the duration of the experiment. Nerve crushing commenced by gradually increasing the force applied to the forceps. At a target decrease in CMAP amplitude of 70%-90%, crushing was halted. CMAPs were continually recorded for 5-20 min after the termination of the crushing event. Nerves were then fixed for histological assessment. The following post-crush mean values from 19 trials were reported: peak CMAP amplitude decreased by 81.6% from baseline, duration of crush was 17 sec, rate of applied force was 0.03 N/sec, and maximal applied force was 0.5 N. A variety of agonal phenomena were evident post-lesion. Following the initial decrease in CMAP, 8 of 19 trials demonstrated a partial and transient recovery, followed by a further decline. Thirteen trials exhibited a CMAP amplitude near zero at the end of the recording. Twelve trials demonstrated a superimposed EMG background response during and after the crush event, with disappearance occurring within 4-8 min. Qualitative histology assessment at the lesion site demonstrated a correspondence between CMAP response and partial sparing of nerve fibers. By using a targeted decline in CMAP amplitude as the endpoint, researchers may be able to produce controlled, brief, and reproducible crush injuries. This model can also be used to test interventions aimed at enhancing subsequent regeneration and behavioral recovery.

Automated Identification of Immunocompromised Status in Critically Ill Children.

BACKGROUND: Easy identification of immunocompromised hosts (ICHs) would allow for stratification of culture results based on host type. METHODS: We utilized antimicrobial stewardship program (ASP) team notes written during handshake stewardship rounds in the pediatric intensive care unit (PICU) as the gold standard for host status; clinical notes from the primary team, medication orders during the encounter, problem list, and billing diagnoses documented prior to the ASP documentation were extracted to develop models that predict host status. We calculated performance for three models based on diagnoses/medications, with and without natural language processing from clinical notes. The susceptibility of pathogens causing bacteremia to commonly used empiric antibiotic regimens was then stratified by host status. RESULTS: We identified 844 antimicrobial episodes from 666 unique patients; 160 (18.9%) were identified as ICHs. We randomly selected 675 initiations (80%) for model training and 169 initiations (20%) for testing. A rule-based model using diagnoses and medications alone yielded a sensitivity of 0.87 (08.6-0.88), specificity of 0.93 (0.92-0.93), and positive predictive value (PPV) of 0.74 (0.73-0.75). Adding clinical notes into XGBoost model led to improved specificity of 0.98 (0.98-0.98) and PPV of 0.9 (0.88-0.91), but with decreased sensitivity 0.77 (0.76-0.79). There were 77 bacteremia episodes during the study period identified and a host-specific visualization was created. CONCLUSIONS: An electronic health record-based phenotype based on notes, diagnoses, and medications identifies ICH in the PICU with high specificity.