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.

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.

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.

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.

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.

Risk Factors for Wound Complication following Primary Total Hip Arthroplasty.

This study assessed the National Surgical Quality Improvement Program (NSQIP), which provides data on 30-day post-operative complications from 500+ institutions, to identify risk factors for wound complications in patients undergoing primary total hip arthroplasty (THA). Patients undergoing primary THA between 2010-2017 were retrospectively reviewed. Patients experiencing post-operative wound complications were stratified based on pre-operative characteristics. Multivariate regression model was used to assess these characteristics as independent risk factors for post-operative complications. Of 119,096 patients undergoing primary THA, 1,264 (1.06%), 280 (0.2%), 622 (0.52%) and 139 (0.12%) experienced wound complications, deep surgical site infection, superficial surgical site infection, and wound dehiscence, respectively. Pre-operative transfusion (p < 0.0001), steroid use (p = 0.01), and obesity (p < 0.0001) were risk factors for wound dehiscence. Pre-operative transfusion (p < 0.0001), cardiac comorbidities (p = 0.02), and steroid use (p = 0.01) were risk factors for superficial surgical site infection. Assessment of the NSQIP identified modifiable risk factors for wound complications following primary THA, including pre-operative transfusion, steroid use, and obesity. (Journal of Surgical Orthopaedic Advances 31(4):242-247, 2022).

Correlation of SARS-CoV-2 Subgenomic RNA with Antigen Detection in Nasal Midturbinate Swab Specimens.

Among symptomatic outpatients, subgenomic RNA of severe acute respiratory syndrome coronavirus 2 in nasal midturbinate swab specimens was concordant with antigen detection but remained detectable in 13 (82.1%) of 16 nasopharyngeal swab specimens from antigen-negative persons. Subgenomic RNA in midturbinate swab specimens might be useful for routine diagnostics to identify active virus replication.

Global Trends in Norovirus Genotype Distribution among Children with Acute Gastroenteritis.

Noroviruses are a leading cause of acute gastroenteritis (AGE) among adults and children worldwide. NoroSurv is a global network for norovirus strain surveillance among children <5 years of age with AGE. Participants in 16 countries across 6 continents used standardized protocols for dual typing (genotype and polymerase type) and uploaded 1,325 dual-typed sequences to the NoroSurv web portal during 2016-2020. More than 50% of submitted sequences were GII.4 Sydney[P16] or GII.4 Sydney[P31] strains. Other common strains included GII.2[P16], GII.3[P12], GII.6[P7], and GI.3[P3] viruses. In total, 22 genotypes and 36 dual types, including GII.3 and GII.20 viruses with rarely reported polymerase types, were detected, reflecting high strain diversity. Surveillance data captured in NoroSurv enables the monitoring of trends in norovirus strains associated childhood AGE throughout the world on a near real-time basis.

Nerve Compression Syndromes of the Shoulder.

Nerve compression syndromes of the shoulder contribute to pain, paresthesia, and weakness of the upper extremity. This review examines the recent literature regarding thoracic outlet syndrome, suprascapular neuropathy, long thoracic nerve palsy, and quadrilateral space syndrome. Overlapping features are common among shoulder pathologies, and thus, key anatomical features, pathophysiology, clinical manifestations, diagnostic techniques, and treatments are highlighted for all aforementioned conditions.

Evaluation of A2 and A4 Hand Pulley Repair Using Tendon Graft Rings.

PURPOSE: To compare the mechanical characteristics of A2 and combined A2-A4 pulley repair in the intact and damaged flexor pulley system. METHODS: After control testing, we recorded tendon excursion and flexion of 11 cadaveric fingers after several interventions: (1) complete excision of A2 and A4, (2) repair of the A2 with one ring of tendon graft, (3) repair of the A2 with 2 rings of tendon graft, and (4) repair of the A2 with 2 rings combined with repair the A4 with one ring. RESULTS: At the proximal interphalangeal (PIP) joint, the maximum rotational angle decreased by an average of 30% after complete excision of the A2 and A4 pulleys. This angle was still decreased compared with the control by an average of 25% after one-ring repair at A2, 23% after 2-ring repair at A2, and 17% after 2-ring repair at A2 combined with one-ring repair at A4. At the metacarpophalangeal joint, the average maximum rotational angle decreased by an average of 17% after complete excision of the A2 and A4 pulleys. This angle was still decreased compared with the control by an average of 11% after one-ring repair at A2, 7% after 2-ring repair at A2, and 4% after 2-ring repair at A2 combined with one-ring repair at A4. Kinematic behavior at the PIP joint with an intact pulley system was most closely approximated by the 3-loop repair. The least similar behavior was with a 2-ring construct at A2. CONCLUSIONS: All repairs increased average flexion at the PIP and metacarpophalangeal joints compared with the unrepaired samples. The 3-ring configuration exhibited a higher recovery of PIP flexion compared with the other repairs. CLINICAL RELEVANCE: Although each repair restored flexion, clinical studies are necessary to evaluate the clinical relevance of the mechanical results of this study.

Preoperative Risk Factors for Postoperative Urinary Tract Infection After Primary Total Hip and Knee Arthroplasties.

BACKGROUND: Establishing clear risk factors for complications such as urinary tract infection (UTI) after arthroplasty procedures helps guide clinical practice and provides more information to both surgeons and patients. This study aims to assess selected preoperative patient characteristics as risk factors for postoperative UTI after primary total hip and knee arthroplasties (THA and TKA). METHODS: This was a retrospective analysis using current procedural terminology codes to investigate the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for patients who underwent THA or TKA from 2010 to 2017. Patients were classified for UTI by NSQIP guidelines. Patient samples with all possible covariates were included for multivariate logistic regression analysis and assessed for independent associations. RESULTS: In a cohort of 983 identified patients (983 of 119,096; 0.83%): ages 57+ years, preoperative red blood cell (RBC) transfusion, perioperative RBC transfusion, bleeding disorders, operative time 110+ minutes, preoperative steroid use, diabetes, pulmonary comorbidities, body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after THA. In a cohort of 1503 identified patients (1503 of 189,327; 0.8%): ages 60+ years, preoperative RBC transfusion, perioperative RBC transfusion, anemia, platelets less than 150k, preoperative steroid use, diabetes, and body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after TKA. Male sex was associated with a decreased risk of UTI in both THA and TKA. CONCLUSION: This study provides novel evidence on risk factors associated with the development of UTI after THA or TKA. Clinicians should be aware of risk factors in the manifestation of postoperative UTI after primary THA or TKA procedures.

Abnormal Coagulation as a Risk Factor for Postoperative Complications After Primary and Revision Total Hip and Total Knee Arthroplasty.

BACKGROUND: Patients undergoing total joint arthroplasty (TJA) have an increased likelihood of having an abnormal coagulation profile compared with the general population. Coagulation abnormalities are often screened for before surgery and considered during perioperative planning. This study assesses a preoperative abnormal coagulation profile as a risk factor for postoperative complications after total hip arthroplasty (THA), revision THA (rTHA), total knee arthroplasty (TKA), and revision TKA (rTKA) and then examines specific coagulopathies to determine their influence on complication rates. METHODS: Patients who underwent THA, rTHA, TKA, or rTKA from 2011 to 2017 were identified in the American College of Surgeons National Surgical Quality Improvement Program database and then assessed for preoperative abnormal coagulation profiles. Various postoperative complications were analyzed for each cohort, and two separate multivariate regression analyses were used to assess the relationship between abnormal coagulation and postoperative complications. RESULTS: 403,566 THA, rTHA, TKA, or rTKA cases were identified, and 40,466 (10.0%) of patients were found to have an abnormal coagulation profile. Patients with preoperative coagulation abnormalities had higher likelihoods of postoperative complications after primary TJA than in revision TJA. An international normalized ratio>1.2 was associated with the most types of postoperative complications, followed by a bleeding disorder diagnosis. A partial thromboplastin time>35 seconds was associated with only one type of postoperative complication, while a platelet count <150,000 per µL was associated with postoperative complications only after TKA. CONCLUSION: TJA in patients with abnormal coagulation profiles may result in adverse outcomes. These patients may benefit from preoperative intervention. Prophylactic care needs to be personalized to the specific coagulation abnormalities present.

A novel method for predicting superior gluteal nerve safe zones in the lateral approach to the hip.

INTRODUCTION: The superior gluteal nerve (SGN) is at risk for laceration during lateral approach total hip arthroplasty (THA). The purpose of this study is to assess the accuracy of the trochanter-to-iliac crest distance (TCD) and the nerve-to-trochanter distance (NTD) ratio in determining a reproducible safe zone around the SGN independent of height. MATERIALS AND METHODS: Eighteen hemipelvises were dissected and the SGNs were exposed. The distance (NTD) from greater trochanter (GT) to the most inferior branch of the SGN encountered in each of the three approaches (Bauer et al., 1979) was measured. A reference distance (TCD) was measured from the GT to the highest point on the iliac crest. The NTD was divided by the TCD to generate standardized ratios. Coefficient of variation CV = (SD/mean) × 100 was calculated for each distance and ratio to measure relative variability. RESULTS: The standardized ratios (and CV) were determined for the nerve branches in three different surgical approaches: Hardinge 0.464 (0.9%), Bauer 0.406 (1.7%), and Frndak 0.338 (4.1%). There was a strong correlation of the individual NTDs with the TCD: NTD for Hardinge (r = 0.996, p < .001), NTD for Bauer (r = 0.984, p < .001), and NTD for Frndak (r = 0.932, p < .001). CONCLUSION: By measuring the TCD preoperatively and using the respective standardized ratios, surgeons can accurately predict the NTD and how proximal to the GT each SGN branch can be expected to be encountered during lateral approach to the hip. This will allow surgeons to work with a more precise safe zone around the SGN and minimize the possibility for a nerve injury.

Histological Assessment of Wallerian Degeneration of the Rat Tibial Nerve Following Crush and Transection Injuries.

BACKGROUND: Wallerian degeneration (WD) following peripheral nerve injury (PNI) is an area of growing focus for pharmacological developments. Clinically, WD presents challenges in achieving full functional recovery following PNI, as prolonged denervation of distal tissues for an extended period of time can irreversibly destabilize sensory and motor targets with secondary tissue atrophy. Our objective is to improve upon histological assessments of WD. METHODS: Conventional methods utilize a qualitative system simply describing the presence or absence of WD in nerve fibers. We propose a three-category assessment that allows more quantification: A fibers appear normal, B fibers have moderate WD (altered axoplasm), and C fibers have extensive WD (myelin figures). Analysis was by light microscopy (LM) on semithin sections stained with toluidine blue in three rat tibial nerve lesion models (crush, partial transection, and complete transection) at 5 days postop and 5 mm distal to the injury site. The LM criteria were verified at the ultrastructural level. This early outcome measure was compared with the loss of extensor postural thrust and the absence of muscle atrophy. RESULTS: The results showed good to excellent internal consistency among counters, demonstrating a significant difference between the crush and transection lesion models. A significant decrease in fiber density in the injured nerves due to inflammation/edema was observed. The growth cones of regenerating axons were evident in the crush lesion group. CONCLUSION: The ABC method of histological assessment is a consistent and reliable method that will be useful to quantify the effects of different interventions on the WD process.

Readability Level of English and Spanish Orthopaedic Patient Education Materials English and Spanish Patient Education.

There are 16 million Hispanic people in the United States who rely on Spanish as their only effective method of communication. However, there is a scarcity of literature evaluating if patient education resources in Spanish meet the average American reading level or National Institute of Health (NIH) and American Medical Association (AMA) grade-level recommendations, especially in the field of orthopaedics. Representative orthopaedic search terms were input into Google and ten articles pertaining to patient education were selected. Videos, scientific journals, and surgical technique guides were excluded. Articles were then digitally analyzed and compared. Mean United States grade level equivalent was 11.26 ± 2.23 for English articles and 10.55 ± 1.45 for Spanish articles. English orthopaedic materials featured a significantly more difficult grade level (p < 0.01) than equivalent Spanish works. Spanish orthopaedic materials generated in the United States featured significantly lower (p < 0.01) readability scores than those written outside the United States. Our study demonstrated both English and Spanish materials were written at a high school level. Spanish materials were written at more appropriate grade-levels than their English counterparts. (Journal of Surgical Orthopaedic Advances 30(2):096-100, 2021).

Role of Depression in Total Knee Arthroplasty: A Retrospective Analysis of Perioperative Outcomes in Patients in the United States.

We evaluate the patient demographics, perioperative outcomes, in-hospital complications, and assess recent national trends in clinically depressed and non-depressed patients undergoing primary total knee arthroplasty (TKA). Using the National Hospital Discharge Survey from 2001 and 2010, patients undergoing primary TKA in the United States were identified based upon the diagnosis of depression. Differences in gender, patient-demographics, comorbidities, complications, length of stay, and discharge disposition were analyzed. A total of 32,761 TKA patients were identified, consisting of 1,880 patients with a diagnosis of depression and 30,881 patients without. The depression group had an average age significantly younger than the non-depression cohort (p < 0.01). The depression group contained a significantly greater percentage of females when compared to the non-depression group. The non-depression group had a significantly greater percentage of African-Americans (p < 0.01), and a significantly smaller percentage of Caucasians (p < 0.01). Our findings contribute to the literature on the role of depression on perioperative outcomes of TKA. (Journal of Surgical Orthopaedic Advances 30(1):007-009, 2021).

Use of Rapid Diagnostics To Manage Pediatric Bloodstream Infections? You Bet Your ASP!

Rapid diagnostic testing (RDT) can facilitate earlier optimization of the treatment of bloodstream infections, particularly in conjunction with an effective antimicrobial stewardship program (ASP). However, the effective implementation and workflow of RDTs are still a matter of debate, particularly in a pediatric setting. In this issue of the Journal of Clinical Microbiology, L. J. Juttukonda, S. Katz, J. Gillon, J. Schmitz, and R. Banerjee (J Clin Microbiol 58:e01400-19, 2020, https://doi.org/10.1128/JCM.01400-19) investigate the impact of a multiplex, molecular RDT on changes to antimicrobial therapy in an academic children's hospital. These data reveal several factors that clinical laboratories should consider prior to the implementation of RDTs for positive blood cultures.

Evaluation of Commercial Molecular Diagnostic Methods for Detection and Determination of Macrolide Resistance in Mycoplasma pneumoniae.

We evaluated six commercial molecular tests targeting Mycoplasma pneumoniae, namely, the BioFire FilmArray respiratory panel (RP), the Meridian Alethia Mycoplasma Direct, the GenMark ePlex respiratory pathogen panel (RPP), the Luminex NxTAG RPP, the ELITech ELITe InGenius Mycoplasma MGB research use only (RUO) PCR, and the SpeeDx Resistance Plus MP assays. Laboratory-developed PCR assays at the University of Alabama at Birmingham and the Centers for Disease Control and Prevention were used as reference standards. Among 428 specimens, 212 were designated confirmed positives for M. pneumoniae The highest clinical sensitivities were found with the InGenius PCR (99.5%) and the FilmArray RP (98.1%). The Resistance Plus MP identified 93.3% of the confirmed-positive specimens, whereas 83.6, 64.6, and 55.7% were identified by the ePlex RPP, NxTAG RPP, and Mycoplasma Direct assays, respectively. There was no significant difference between the sensitivity of the reference methods and that of the FilmArray RP and InGenius assays, but the remaining four assays detected significantly fewer positive specimens (P < 0.05). Specificities of all assays were 99.5 to 100%. The Resistance Plus MP assay detected macrolide resistance in 27/33 specimens, resulting in a sensitivity of 81.8%. This study provides the first large-scale comparison of commercial molecular assays for detection of M. pneumoniae in the United States and identified clear differences among their performance. Additional studies are necessary to explore the impact of various test performances on patient outcome.

Cryptosporidiosis among solid organ transplant recipient attendees at a summer camp.

We report a cluster of pediatric cryptosporidiosis infections among solid organ transplant recipients at a summer camp in Georgia, USA. A retrospective cohort study was conducted to investigate the risk factors for infection. A total of 118 campers attended the camp during July 23-28, 2017. The overall attack rate among campers during the outbreak was 11% (13/118). Sanger-based amplicon sequencing of stool specimens from 7 (80%) campers identified Cryptosporidium hominis as the suspected etiologic agent. All infected campers were heart or kidney transplant recipients receiving immunosuppressive therapy. The median reported symptom duration was 12 days (range 6-18 days) and 9 (69.2%) were hospitalized for at least one night (median length of stay 5 days, range 2-16 days). There were no deaths or acute rejection events attributed to infection. The results of the epidemiologic and environmental investigation suggest a recreational pool as the presumed source, although there was no direct evidence to support this. Many long-term interventions were implemented, and there have been no further outbreaks at the camp in the following two years. This outbreak demonstrates that cryptosporidiosis may be associated with notable burden in pediatric transplant recipients, and illustrates the challenges associated with source identification and containment.

Does Virtual Reality Improve Procedural Completion and Accuracy in an Intramedullary Tibial Nail Procedure? A Randomized Control Trial.

BACKGROUND: Artificial reality technologies are currently being explored as potential options to improve surgical education. Previous studies have primarily examined the efficacy of artificial reality in laparoscopic procedures, but to our knowledge, none have been performed in orthopaedically relevant procedures such as intramedullary tibial nailing, which calls for more versatile large-scale movements. QUESTIONS/PURPOSES: Does a virtual reality simulator with or without a standard technique guide result in (1) a higher proportion of participants who completed the insertion of an intramedullary tibial nail in a synthetic bones model and (2) greater procedural accuracy than does training with a technique guide alone? METHODS: Twenty-five first- and second-year medical students without prior exposure to intramedullary tibial nail insertion were recruited. Participants were randomly assigned to the technique guide control group (n = 8), the virtual reality group (n = 8), or the virtual reality and technique guide group (n = 9). The technique guide was adapted from a commercially available technique guide, which participants in the assigned groups could use to prepare as much as desired. The virtual reality simulation was based on the same procedure, and we used a commercially available virtual reality simulator that we purchased for this task. Participants in the virtual reality experimental groups completed the simulation on three separate sessions, at a set interval of 3 to 4 days apart. After 10 to 14 days of preparation, all participants attempted to insert an intramedullary nail into an intact, compact bone-model tibia that lacked surrounding soft tissue. Participants were given written hints if requested, but no other assistance was given. A procedure was considered complete if the nail and screw were properly placed. Procedural accuracy was defined as the number of incorrect steps normalized out of the 16 possible performed. After the procedure, one orthopaedic surgeon assessed a blinded video of the participant performing it so the assessor could not recognize the individual or that individual's gender. Additionally, the assessor was unaware of which group each participant had been randomized to during the evaluation. RESULTS: A higher proportion of participants in the virtual reality group (6 of 8) and the virtual reality and technique guide group (7 of 9) completed the intramedullary nail than did participants in the technique guide group (2 of 8; p = 0.01). There was no difference in completion between the virtual reality groups (p = 0.89). Participants in the virtual reality and virtual reality and technique guide had fewer normalized incorrect steps than did participants in the technique guide group (3.2 ± 0.1 of 16 and 3.1 ± 0.1 of 16 versus 5.7 ± 0.2 of 16, respectively; p = 0.02 for comparisons of virtual reality groups to technique guide, p = 0.63 between the virtual reality group). CONCLUSIONS: Virtual reality increased both procedural accuracy and the completion proportion compared with a technique guide in medical students. Based on our findings, virtual reality may help residents learn the procedural workflow and movements required to perform surgical procedures. Future studies should examine how and when exactly the technology can be applied to residencies and its impact on residents. LEVEL OF EVIDENCE: Level I, therapeutic study.