Laboratory analysis of blood cultures is vital to the accurate and timely diagnosis of bloodstream infections. However, the reliability of the test depends on clinical compliance with standard operating procedures that limit the risk of inconclusive or incorrect results. False-negative blood culture results due to inadequate volumes of blood can result in misdiagnosis, delay therapy, and increase patients' risk of developing or dying from bloodstream infections. Likewise, commonly occurring bacteria or fungi on human skin (i.e., commensal organisms) can contaminate the blood culture during collection and increase the risk of false positives, compromising care and leading to unnecessary antibiotic therapy and prolonged hospitalization. In December 2022, a Centers for Medicare & Medicaid Services (CMS) consensus-based entity (CBE) endorsed the Centers for Disease Control and Prevention's (CDC) proposal for a new patient safety measure to address these concerns. CDC developed this quality measure to promote the standardization of blood culture best practices and improve laboratory diagnosis of bloodstream infections nationally. This special report will emphasize the importance of standardizing blood culture collection and describe the need for a national patient safety measure, new quality tools, and next steps.

SUMMARYClinical medicine has embraced the use of evidence for patient treatment decisions; however, the evaluation strategy for evidence in laboratory medicine practices has lagged. It was not until the end of the 20th century that the Institute of Medicine (IOM), now the National Academy of Medicine, and the Centers for Disease Control and Prevention, Division of Laboratory Systems (CDC DLS), focused on laboratory tests and how testing processes can be designed to benefit patient care. In collaboration with CDC DLS, the American Society for Microbiology (ASM) used an evidence review method developed by the CDC DLS to develop a program for creating laboratory testing guidelines and practices. The CDC DLS method is called the Laboratory Medicine Best Practices (LMBP) initiative and uses the A-6 cycle method. Adaptations made by ASM are called Evidence-based Laboratory Medicine Practice Guidelines (EBLMPG). This review details how the ASM Systematic Review (SR) Processes were developed and executed collaboratively with CDC's DLS. The review also describes the ASM transition from LMBP to the organization's current EBLMPG, maintaining a commitment to working with agencies in the U.S. Department of Health and Human Services and other partners to ensure that EBLMPG evidence is readily understood and consistently used.

OBJECTIVES:Developing an expanded representation of the total testing process that includes contemporary elements of laboratory practice can be useful to understanding and optimizing testing workflows across clinical laboratory and patient care settings. METHODS:Published literature and meeting reports were used by the coauthors to inform the development of the expanded representation of the total testing process and relevant examples describing its uses. RESULTS:A visual representation of the total testing process was developed and contextualized to patient care scenarios using a number of examples covering the detection of blood culture contamination, use of next-generation sequencing, and pharmacogenetic testing. CONCLUSIONS:The expanded representation of the total testing process can serve as a model and framework to document and improve the use of clinical testing within the broader context of health care delivery. This representation recognizes increased engagement among clinical laboratory professionals with patients and other health care providers as essential to making informed decisions. The increasing use of data is highlighted as important to ensuring quality, appropriate test utilization, and sustaining an efficient workflow across clinical laboratory and patient care settings. Maintaining a properly resourced and competent workforce is also featured as an essential component to the testing process.

COVID-19 has brought unprecedented challenges to clinical and public health laboratories. While U.S. laboratories have continued striving to provide quality test results during the pandemic, the uncertainty and lack of supplies became a significant hurdle, hindering day-to-day laboratory operations and the ability to increase testing capacity for both SARS-CoV-2 and non-COVID-19 testing. In addition, long-standing laboratory workforce shortages became apparent, hindering the ability of clinical and public health laboratories to rapidly increase testing. The American Society for Microbiology, the College of American Pathologists, the National Coalition of STD Directors, and the Emerging Infections Network independently conducted surveys in 2020 and early 2021 to assess the capacity of the nation's clinical laboratories to respond to the increase in demand for testing during the COVID-19 pandemic. The results of these surveys highlighted the shortages of crucial supplies for SARS-CoV-2 testing and supplies for other routine laboratory diagnostics, as well as a shortage of trained personnel to perform testing. The conclusions are based on communications, observations, and the survey results of the clinical laboratory, public health, and professional organizations represented here. While the results of each survey considered separately may not be representative of the entire community, when considered together they provide remarkably similar results, further validating the findings and highlighting the importance of laboratory supply chains and the personnel capable of performing these tests for any response to a large-scale public health emergency.

Patient care and public health require timely, reliable laboratory testing. However, clinical laboratory professionals rarely know whether patient specimens contain infectious agents, making ensuring biosafety while performing testing procedures challenging. The importance of biosafety in clinical laboratories was highlighted during the 2014 Ebola outbreak, where concerns about biosafety resulted in delayed diagnoses and contributed to patient deaths. This review is a collaboration between subject matter experts from large and small laboratories and the federal government to evaluate the capability of clinical laboratories to manage biosafety risks and safely test patient specimens. We discuss the complexity of clinical laboratories, including anatomic pathology, and describe how applying current biosafety guidance may be difficult as these guidelines, largely based on practices in research laboratories, do not always correspond to the unique clinical laboratory environments and their specialized equipment and processes. We retrospectively describe the biosafety gaps and opportunities for improvement in the areas of risk assessment and management; automated and manual laboratory disciplines; specimen collection, processing, and storage; test utilization; equipment and instrumentation safety; disinfection practices; personal protective equipment; waste management; laboratory personnel training and competency assessment; accreditation processes; and ethical guidance. Also addressed are the unique biosafety challenges successfully handled by a Texas community hospital clinical laboratory that performed testing for patients with Ebola without a formal biocontainment unit. The gaps in knowledge and practices identified in previous and ongoing outbreaks demonstrate the need for collaborative, comprehensive solutions to improve clinical laboratory biosafety and to better combat future emerging infectious disease outbreaks.

The evidence base for the optimal laboratory diagnosis of Clostridioides (Clostridium) difficile in adults is currently unresolved due to the uncertain performance characteristics and various combinations of tests. This systematic review evaluates the diagnostic accuracy of laboratory testing algorithms that include nucleic acid amplification tests (NAATs) to detect the presence of C. difficile. The systematic review and meta-analysis included eligible studies (those that had PICO [population, intervention, comparison, outcome] elements) that assessed the diagnostic accuracy of NAAT alone or following glutamate dehydrogenase (GDH) enzyme immunoassays (EIAs) or GDH EIAs plus C. difficile toxin EIAs (toxin). The diagnostic yield of NAAT for repeat testing after an initial negative result was also assessed. Two hundred thirty-eight studies met inclusion criteria. Seventy-two of these studies had sufficient data for meta-analysis. The strength of evidence ranged from high to insufficient. The uses of NAAT only, GDH-positive EIA followed by NAAT, and GDH-positive/toxin-negative EIA followed by NAAT are all recommended as American Society for Microbiology (ASM) best practices for the detection of the C. difficile toxin gene or organism. Meta-analysis of published evidence supports the use of testing algorithms that use NAAT alone or in combination with GDH or GDH plus toxin EIA to detect the presence of C. difficile in adults. There is insufficient evidence to recommend against repeat testing of the sample using NAAT after an initial negative result due to a lack of evidence of harm (i.e., financial, length of stay, or delay of treatment) as specified by the Laboratory Medicine Best Practices (LMBP) systematic review method in making such an assessment. Findings from this systematic review provide clarity to diagnostic testing strategies and highlight gaps, such as low numbers of GDH/toxin/PCR studies, in existing evidence on diagnostic performance, which can be used to guide future clinical research studies.

SUMMARY Background. Urinary tract infection (UTI) in the United States is the most common bacterial infection, and urine cultures often make up the largest portion of workload for a hospital-based microbiology laboratory. Appropriately managing the factors affecting the preanalytic phase of urine culture contributes significantly to the generation of meaningful culture results that ultimately affect patient diagnosis and management. Urine culture contamination can be reduced with proper techniques for urine collection, preservation, storage, and transport, the major factors affecting the preanalytic phase of urine culture. Objectives. The purposes of this review were to identify and evaluate preanalytic practices associated with urine specimens and to assess their impact on the accuracy of urine culture microbiology. Specific practices included collection methods for men, women, and children; preservation of urine samples in boric acid solutions; and the effect of refrigeration on stored urine. Practice efficacy and effectiveness were measured by two parameters: reduction of urine culture contamination and increased accuracy of patient diagnosis. The CDC Laboratory Medicine Best Practices (LMBP) initiative's systematic review method for assessment of quality improvement (QI) practices was employed. Results were then translated into evidence-based practice guidelines. Search strategy. A search of three electronic bibliographic databases (PubMed, SCOPUS, and CINAHL), as well as hand searching of bibliographies from relevant information sources, for English-language articles published between 1965 and 2014 was conducted. Selection criteria. The search contained the following medical subject headings and key text words: urinary tract infections, UTI, urine/analysis, urine/microbiology, urinalysis, specimen handling, preservation, biological, preservation, boric acid, boric acid/borate, refrigeration, storage, time factors, transportation, transport time, time delay, time factor, timing, urine specimen collection, catheters, indwelling, urinary reservoirs, continent, urinary catheterization, intermittent urethral catheterization, clean voided, midstream, Foley, suprapubic, bacteriological techniques, and microbiological techniques. Main results. Both boric acid and refrigeration adequately preserved urine specimens prior to their processing for up to 24 h. Urine held at room temperature for more than 4 h showed overgrowth of both clinically significant and contaminating microorganisms. The overall strength of this body of evidence, however, was rated as low. For urine specimens collected from women, there was no difference in rates of contamination for midstream urine specimens collected with or without cleansing. The overall strength of this evidence was rated as high. The levels of diagnostic accuracy of midstream urine collection with or without cleansing were similar, although the overall strength of this evidence was rated as low. For urine specimens collected from men, there was a reduction in contamination in favor of midstream clean-catch over first-void specimen collection. The strength of this evidence was rated as high. Only one study compared midstream collection with cleansing to midstream collection without cleansing. Results showed no difference in contamination between the two methods of collection. However, imprecision was due largely to the small event size. The diagnostic accuracy of midstream urine collection from men compared to straight catheterization or suprapubic aspiration was high. However, the overall strength of this body of evidence was rated as low. For urine specimens collected from children and infants, the evidence comparing contamination rates for midstream urine collection with cleansing, midstream collection without cleansing, sterile urine bag collection, and diaper collection pointed to larger reductions in the odds of contamination in favor of midstream collection with cleansing over the other methods of collection. This body of evidence was rated as high. The accuracy of diagnosis of urinary tract infection from midstream clean-catch urine specimens, sterile urine bag specimens, or diaper specimens compared to straight catheterization or suprapubic aspiration was varied. Author's conclusions. No recommendation for or against is made for delayed processing of urine stored at room temperature, refrigerated, or preserved in boric acid. This does not preclude the use of refrigeration or chemical preservatives in clinical practice. It does indicate, however, that more systematic studies evaluating the utility of these measures are needed. If noninvasive collection is being considered for women, midstream collection with cleansing is recommended, but no recommendation for or against is made for midstream collection without cleansing. If noninvasive collection is being considered for men, midstream collection with cleansing is recommended and collection of first-void urine is not recommended. No recommendation for or against is made for collection of midstream urine without cleansing. If noninvasive collection is being considered for children, midstream collection with cleansing is recommended and collection in sterile urine bags, from diapers, or midstream without cleansing is not recommended. Whether midstream collection with cleansing can be routinely used in place of catheterization or suprapubic aspiration is unclear. The data suggest that midstream collection with cleansing is accurate for the diagnosis of urinary tract infections in infants and children and has higher average accuracy than sterile urine bag collection (data for diaper collection were lacking); however, the overall strength of evidence was low, as multivariate modeling could not be performed, and thus no recommendation for or against can be made.

The real-life cases in the Pediatrics in Review popular Index of Suspicion feature have intrigued and educated medical professionals for many years with unique cases to review and evaluate.Now the renowned journal's editors have selected their "top 100" cases to create a fascinating collection that serves as a valuable mini-reference and learning too.

SUMMARY Background. Bloodstream infection (BSI) is a major cause of morbidity and mortality throughout the world. Rapid identification of bloodstream pathogens is a laboratory practice that supports strategies for rapid transition to direct targeted therapy by providing for timely and effective patient care. In fact, the more rapidly that appropriate antimicrobials are prescribed, the lower the mortality for patients with sepsis. Rapid identification methods may have multiple positive impacts on patient outcomes, including reductions in mortality, morbidity, hospital lengths of stay, and antibiotic use. In addition, the strategy can reduce the cost of care for patients with BSIs. Objectives. The purpose of this review is to evaluate the evidence for the effectiveness of three rapid diagnostic practices in decreasing the time to targeted therapy for hospitalized patients with BSIs. The review was performed by applying the Centers for Disease Control and Prevention's (CDC's) Laboratory Medicine Best Practices Initiative (LMBP) systematic review methods for quality improvement (QI) practices and translating the results into evidence-based guidance (R. H. Christenson et al., Clin Chem 57 :816–825, 2011, http://dx.doi.org/10.1373/clinchem.2010.157131 ). Search strategy. A comprehensive literature search was conducted to identify studies with measurable outcomes. A search of three electronic bibliographic databases (PubMed, Embase, and CINAHL), databases containing “gray” literature (unpublished academic, government, or industry evidence not governed by commercial publishing) (CIHI, NIHR, SIGN, and other databases), and the Cochrane database for English-language articles published between 1990 and 2011 was conducted in July 2011. Dates of search. The dates of our search were from 1990 to July 2011. Selection criteria. Animal studies and non-English publications were excluded. The search contained the following medical subject headings: bacteremia; bloodstream infection; time factors; health care costs; length of stay; morbidity; mortality; antimicrobial therapy; rapid molecular techniques, polymerase chain reaction (PCR); in situ hybridization, fluorescence; treatment outcome; drug therapy; patient care team; pharmacy service, hospital; hospital information systems; Gram stain; pharmacy service; and spectrometry, mass, matrix-assisted laser desorption-ionization. Phenotypic as well as the following key words were searched: targeted therapy; rapid identification; rapid; Gram positive; Gram negative; reduce(ed); cost(s); pneumoslide; PBP2; tube coagulase; matrix-assisted laser desorption/ionization time of flight; MALDI TOF; blood culture; EMR; electronic reporting; call to provider; collaboration; pharmacy; laboratory; bacteria; yeast; ICU; and others. In addition to the electronic search being performed, a request for unpublished quality improvement data was made to the clinical laboratory community. Main results. Rapid molecular testing with direct communication significantly improves timeliness compared to standard testing. Rapid phenotypic techniques with direct communication likely improve the timeliness of targeted therapy. Studies show a significant and homogeneous reduction in mortality associated with rapid molecular testing combined with direct communication. Author's conclusions. No recommendation is made for or against the use of the three assessed practices of this review due to insufficient evidence. The overall strength of evidence is suggestive; the data suggest that each of these three practices has the potential to improve the time required to initiate targeted therapy and possibly improve other patient outcomes, such as mortality. The meta-analysis results suggest that the implementation of any of the three practices may be more effective at increasing timeliness to targeted therapy than routine microbiology techniques for identification of the microorganisms causing BSIs. Based on the included studies, results for all three practices appear applicable across multiple microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive S. aureus (MSSA), Candida species, and Enterococcus species.

A previously healthy 6-year-old female child presented to the outpatient clinic with a generalized erythematous, annular, slightly raised and mildly pruritic rash that was present primarily on the right upper arm for 1 week. She complained of low-grade fever (up to 37.9°C), myalgia and fatigue. One week previously, her primary physician had treated her with oral azithromycin and cephalexin for the rash. Despite this, the rash worsened, and lesions were present on the trunk, face and neck, sparing palms and soles. The patient denied respiratory symptoms, diarrhea, vomiting, headache, recent travel and tick bite exposure. Her medical history included only allergic rhinitis treated with diphenhydramine and montelukast. The patient’s mother and 15-year-old sister, both of whom had familial Mediterranean fever, developed a similar rash on their face, arms and trunk. In addition, the boyfriend of the 15-year-old sister and the playmate of the patient who frequently visited the home had begun to develop similar lesions. The family reported owning 1 rat, 3 cats and 3 dogs. They volunteered regularly in an animal shelter and had recently adopted a kitten found in a trash dumpster. The patient and the other family members had been in close contact with the kitten. When initially adopted, the kitten had an annular erythematous rash, cough, runny nose and hair loss, which was improving with antibiotics treatment. On examination, the patient was alert, oriented, afebrile and active with a pulse of 94 beats/min and blood pressure of 103/57 mm Hg. The patient had no neck stiffness, adenopathy, photophobia or organomegaly. She had extensive raised, erythematous, annular and papular crusting lesions on the trunk, neck, face and on the medial aspect of the upper extremities (see Fig., Supplemental Digital Content 1, https://links.lww.com/INF/B165). A few lesions were present on the lower extremities and back. There were no vesicles, ulcers or bullous lesions. No desquamation of skin was noted, and the palms and soles were free of lesions. The mother and sister had similar lesions. Complete blood count with a differential and serum electrolytes were all normal. Serologic testing of both the patient and her elder sister was negative for Rickettsia and Rocky Mountain spotted fever IgG and IgM. Typhus fever group AB IgG and IgM were <1:64. An office procedure was performed that confirmed the diagnosis. For denouement see p. 1002.

An 11-year-old boy with relapsed Ewing sarcoma complicated by pulmonary metastases was hospitalized in early September with fever, neutropenia, and worsening posterior thigh pain. He completed the most recent round of chemotherapy with topotecan, cyclophosphamide, and vincristine within 1 week before admission. Two days before admission, he began complaining of pain in his right upper posterior thigh. His father noted a small, less than 1 cm diameter, black, circular lesion in the area, thought to be a bruise. The patient denied recent trauma to his leg. Four days before hospitalization, he removed a small sliver from the sole of his left foot while visiting a local lake on the Iowa-Nebraska state borders. He waded, but did not swim in the lake. He also incurred mosquito bites on the lower extremities that day. On the day of admission, the patient had a fever of 38.6°C, pulse of 128/minute, respiratory rate of 20/minute, and blood pressure of 117/64 mm Hg. He was a well-appearing male with alopecia. Physical examination was notable for a loose primary lower left canine (#22) with a purple hue to the underlying gum, normal heart and lung examinations, an accessed port in his central chest that was clean and intact, a liver edge palpable just below the costal margin, and normal extremities. The skin examination revealed a mosquito bite on each of his anterior shins, a small puncture site at the location of the sliver he incurred in the sole of his left foot without any surrounding erythema, and a 1.5-cm gray-black macular lesion on his posterior superior right thigh. Laboratory findings revealed a white blood cell count of 270/μL with 20% neutrophils (absolute neutrophil count 50/μL), 72% lymphocytes, and 8% monocytes, hemoglobin 10.2 g/dL, hematocrit 29.5%, and platelets 45,000/μL. He was treated with cefepime and vancomycin empirically for fever and neutropenia. During the next 24 hours in the hospital, the posterior, medial, upper thigh lesion grew to 3 cm in diameter. It remained macular and developed central, target-like clearing surrounded by a gray inner ring and black outer ring. An additional 1.5-cm ring of erythema encircled the lesion. It was not ulcerated, necrotic, or fluctuant, and had no associated drainage or visible disruption of the superficial skin. The antimicrobial regimen was changed to liposomal amphotericin B, gentamicin, piperacillin-tazobactam, and vancomycin was continued. He underwent wide surgical excision of the lesion late on the second hospital day. Biopsy of the lesion and cultures were diagnostic (Fig., Supplemental Digital Content 1, https://links.lww.com/INF/A892). Denouement Permanent tissue sections stained with hematoxylin and eosin and Gomori's methenamine silver revealed the presence of sparsely septate, hyaline, irregularly branching hyphae with thin, nonparallel walls (Fig., Supplemental Digital Content 1, https://links.lww.com/INF/A892). The hyphae were 5 to 8 μm in width and occluded vessel lumens, with resulting thrombosis, invasion of the surrounding vessel walls, and extension into the surrounding soft tissue. There was a marked lack of inflammatory response to this process presumptively secondary to the patient's neutropenic state. The histologic appearance was not that of Aspergillus or a zygomycete. It involved the majority of the superficial and deep vessels of the skin and subcutaneous tissue but spared the epidermis. The presence of hyphae at one of the lateral surgical margins was seen on the silver stain, suggesting that diseased tissue remained in situ. The direct calcofluor white fungal stain showed the presence of fungal hyphae. Fungal cultures were initially set up on inhibitory mold agar and brain heart infusion agar. Growth of flat, spreading, cream-colored colonies with few aerial hyphae occurred at day 3 on these media as well as on the chocolate agar plate. Culture on additional agar plates including potato flake and Mycosel agars showed no sporulation and the preliminary culture report was "nonsporulating hyaline mold; unable to identify by routine methods." The isolate was referred to Dr. Michael Rinaldi at the Fungus Testing Laboratory, University of Texas Health Science Center in San Antonio, TX, where identification of Pythium insidiosum was confirmed by molecular sequencing (D1/D2). Although there are no defined breakpoints for the MICs for P. insidiosum, susceptibility testing yielded 24-hour MICs reading of 1 μg/mL for amphotericin B, 0.06 μg/mL for voriconazole, 4 μg/mL for posaconazole, and 2 μg/mL for terbinafine. The in vitro combinations of posaconazole and terbinafine, and voriconazole and terbinafine both appeared synergistic. The patient became afebrile on the first postoperative day. Neutropenia resolved with human granulocyte colony-stimulating factor injections, achieving an absolute neutrophil count greater than 1000/μL on postoperative day 3. Antibacterial therapy was subsequently discontinued. Computed tomography of the sinuses, chest, abdomen, and pelvis showed no signs of disseminated fungal infection and an echocardiogram was normal. He received 7 days of intravenous liposomal amphotericin B at 5 mg/kg daily. Antifungal therapy was changed to oral voriconazole, 200 mg twice daily following loading dosage, on postoperative day 6 in preparation for hospital discharge. The patient received a total of 9 months of oral voriconazole, discontinuing treatment 2 months after his final round of chemotherapy for relapsed Ewing sarcoma. Pythium insidiosum is an aquatic oomycete in the Kingdom Straminipila. Of the 127 species currently classified in the genus Pythium, it is the only one known to infect animals and humans in addition to plants.1 It is phylogenetically more closely related to algae than to true fungi, though it can be confused with fungal pathogens from the class zygomycetes that have morphologically similar hyaline, but much larger diameter hyphae-like structures.2Pythium insidiosum exists in 2 forms: as biflagellate motile zoospores that swim to and encyst on the host, and as irregularly branching, thin, nonparallel walled hyaline hyphae-like elements with rare septations which germinate in the tissue. The asexual zoospores have an affinity for lily and grass plants as well as human and animal hair and tissue. Encystment and formation of a germ tube occurs at the follicular end of a hair or at the edge of injured tissue leading to invasion and infection in the host. The hyphae-like elements are strongly angiotropic and invade and grow within blood vessels.1,3 Pythiosis insidiosi, infection caused by Pythium insidiosum, commonly manifests as cutaneous, pulmonary, intestinal, or osseous infections in horses, cattle, cats, and dogs. Pythium insidiosum was first reported as a human pathogen in 1985.3 It causes 4 major clinical syndromes in humans: cutaneous or subcutaneous painful, ulcerating lesions, ocular infection, vascular disease leading to arterial occlusion, and disseminated disease.4 The majority of pythiosis cases in human beings reported are from Thailand, and patients typically have a history of an agricultural career with significant exposure to swampy areas. Epidemiologic analyses highlight that 85% of patients with cutaneous, vascular, and disseminated disease had underlying thalassemia-hemoglobinopathy syndrome, but the majority of patients with ocular pythiosis had no underlying disease.4,5 Human pythiosis has also been reported in Australia, Brazil, Haiti, Malaysia, New Zealand, and the United States.6 Disease in the United States has mainly manifested in the ocular form with the exception of a case report describing a neutropenic 12-year-old child with AML who developed P. insidiosum pleuropericarditis complicating pneumonia.7 Two definitive cases and 5 additional putative cases of orbital pythiosis have been reported in the United States.2,8 These occurred in otherwise healthy children with exposures in states where pythiosis is endemic or has been diagnosed in animals (Oklahoma, Tennessee, Florida, Texas, and Arizona).2 Our patient is very unusual in that he had no history of recent travel to areas with endemic pythiosis. Review of the literature reports no cases from Nebraska. Diagnostic methods for identifying Pythium insidiosum include serologic tests, PCR, and DNA sequencing once the organism has been isolated from the patient. Successful treatment of human pythiosis generally requires surgical excision or amputation of the infected site. Employing antimicrobial therapy for pythiosis is challenging because Pythium species may lack ergosterol, a typical target for antifungal therapy. However, the cell walls of Pythium species do contain β-glucan, the target of many newer antifungal drugs.4 There are case reports demonstrating successful use of traditional antifungals with and without surgical excision, including amphotericin B, itraconazole, and terbinafine.8,9 Susceptibility testing has been performed to guide treatment in past cases and was helpful in guiding our patient's postsurgical treatment regimen. Immunotherapy with a P. insidiosum vaccine with and without surgery has been used successfully in animals and in a few human beings on a compassionate basis.4 We suspect that our patient was infected with Pythium insidiosum via integumentary defects while wading in a local lake, and that his immunocompromised state secondary to chemotherapy contributed to the pathogenicity of the organism. Treatment involving wide surgical excision combined with susceptibility-guided antifungal therapy with oral voriconazole has proven successful thus far in our patient. Now, more than 1 year after initial infection, he continues to do well off chemotherapy and remains symptom-free. This is a particularly unique case in both the geographic location of presentation and in the severe immunocompromised condition of the patient, differing from the well-described association of pythiosis with thalassemia and Southeast Asia. Clinician awareness of this emerging, potentially life-threatening infectious oomycete is imperative to improving patient outcomes worldwide. ACKNOWLEDGMENTS The authors thank Dr. Michael Rinaldi at the Fungus Testing Laboratory, University of Texas Health Science Center, San Antonio, TX, for his expert consultation and editorial advice.

A previously healthy 17-year-old white girl initially presented to a local urgent care with 2 days of headache, sore throat, and fever of 104°F. Rapid Group A Streptococcus testing on a pharyngeal swab was negative, and her complete blood count (CBC) revealed a white blood cell count (WBC) of 18 300 mm-3, with 91% neutrophils. Hemoglobin (Hgb) was 14 g/dL, hematocrit 41%, and platelet count 194 000 mm-3. She was diagnosed with a viral illness and discharged home with supportive therapy. Her fever and sore throat persisted, and on day 5 of illness, she developed pain in her left chest and right hip. An urgent care facility practitioner prescribed supportive care. Over the next few days her chest and hip pain increased, and she could not bear weight on her right leg. On the eighth day of illness, she presented to a community hospital emergency room with significant pain in her hip and chest and hypovolemic shock. She had a marked leukocytosis of 40 000 mm-3, with 50% neutrophils, 32% bands, 4% lymphocytes, 1% eosinophils, 1% monocytes, 9% metamyelocytes, and 3% myelocytes. In addition, there was evidence of disseminated intravascular coagulation and elevated blood urea nitrogen, creatinine, and pancreatic and hepatic enzymes. After aggressive fluid resuscitation and hospitalization, her empirical therapy included IV vancomycin, clindamycin, and ceftriaxone. A chest CT scan revealed a large left-sided empyema with multiple septic emboli and nodularity of the thymus. Because of a concern for possible malignancy, she underwent diagnostic thoracocentesis and bone marrow aspiration. CT scan of her lower extremity confirmed a diagnosis of necrotizing fasciitis. She underwent extensive debridement of her right buttock, flank, and thigh (Figure 1). Her blood, wound, and pleural fluid cultures grew Fusobacterium necrophorum and Peptostreptococcus. She was empirically started on low-molecular-weight heparin, although there was no evidence of thrombosis. Postoperatively, she developed acute respiratory distress syndrome, required multiple chest tubes to drain pleural effusion, and multiple blood products. Her lowerextremity wound required repeated surgical debridement and vacuum-assisted wound closure. She remained in hospital for 7 weeks during which her parenteral therapy included 3 weeks of vancomycin, 6 weeks of clindamycin, 10 days of penicillin, and 2 weeks of liposomal amphotericin B for catheter-related

The VITEK 2 and Phoenix extended-spectrum beta-lactamase (ESBL) detection systems, which comprise confirmatory tests and expert systems, were evaluated for their ability to discriminate between 102 well-characterized strains of ESBL-positive or -negative Escherichia coli, Klebsiella pneumoniae, and Klebsiella oxytoca. At least 38 distinct ESBLs were included. The strains were chosen to include some known to cause false-positive and false-negative CLSI ESBL confirmatory test results. Therefore, enzyme characterizations, rather than CLSI tests, were the reference methods for the Phoenix and VITEK 2 evaluations. A third arm of the study was conducted with the Phoenix test using two normally inactive expert rules intended to enhance ESBL detection, in addition to using the currently available software. The Phoenix ESBL confirmatory test and unmodified expert system exhibited 96% sensitivity and 81% specificity for ESBL detection. Activation of the two additional rules increased sensitivity to 99% but reduced the specificity to 58%. The VITEK 2 ESBL confirmatory test exhibited 91% sensitivity, which was reduced to 89% sensitivity by its expert system, while its specificity was 85%. Many of the expert system interpretations of both instruments were helpful, but some were suboptimal. The VITEK 2 expert system was potentially more frustrating because it provided more inconclusive interpretations of the results. Considering the high degree of diagnostic difficulty posed by the strains, both ESBL confirmatory tests were highly sensitive. The expert systems of both instruments require modification to update and enhance their utility.

BACKGROUND:A ready-to-use, standardized Candida albicans skin test product (Candin) first became available in 1995. As of April 6, 2004, no published reports have been found describing efficacy or safety with pediatric use of this reagent.OBJECTIVE:To present a case series describing experience with use of Candin to assess 78 pediatric cases for delayed-type hypersensitivity.METHODS:The standardized C. albicans reagent was one of up to 4 antigens used to evaluate patients' cellular immunity. Candin was used with purified protein derivative tuberculosis testing for 76 patients (4 mo-16 y of age) and for anergy testing alone in 2 cases. Candin was used with at least one other skin test reagent for 24 subjects.RESULTS:Fifty-three of 78 subjects (68%) responded to at least one skin test antigen. Candin had an overall response rate of 64% (50/78). There was a response to Candin in 54% (13/24) of subjects with multiple reagents applied, the highest rate of any antigen used. There was a 27% (3/11) positive Candin response for subjects <1 year of age; this compared with 21% and 23% in 2 published reports on use of nonstandardized tests for this age group. No adverse events were associated with use of Candin.CONCLUSIONS:Candin testing gives similar or better response rates compared with published data on older, nonstandardized C. albicans reagents and other anergy test antigens used in this case series. It should be used in combination with multiple other control antigens to most effectively assess for anergy, particularly in infants, as well as in patients recognized to be immune deficient.

Keywords KRUPP BURSTS, EXPLOSIONS, GUNS, METHODS, REPAIRS, RIVERS, PRESSURE, FRACTURE, WAVES, GUNPOWDER, ARTILLERY, ACCIDENTS, EXPLOSIVES, BREECHES MIN, FOOCHOW CHINA, ASIA... Show All