Antimycobacterial Susceptibility Testing of Nontuberculous Mycobacteria.

Recommendations for first-line and second-line drug testing and organism group, specific methodologies, and reporting recommendations have been addressed by the Clinical and Laboratory Standards Institute (CLSI) and are important in the selection of appropriate antimicrobial treatment regimens for nontuberculous mycobacteria (NTM) disease. This review also includes recent information on new antimicrobials proposed for the treatment of NTM but not yet addressed by the CLSI and molecular (gene sequencing) methods associated with the detection of antimicrobial resistance of two major therapeutic antimicrobials, clarithromycin and amikacin.

Routine pathologic examination of tonsillectomy specimens: A 10-year experience at a tertiary care children's hospital.

Objective: To review histopathologic diagnoses from tonsillectomy specimens and determine whether routine pathologic exam is necessary.

Methods: Pathology reports of patients undergoing tonsillectomy from 2005 to 2014 at our pediatric tertiary care hospital were reviewed. Histopathologic diagnoses were recorded with special attention to identification of malignancy.

Pelvic Abscess Secondary to Mycoplasma Hominis after Vaginal Laceration.

Background: Mycoplasma hominis frequently colonizes the urogenital and respiratory tracts of healthy individuals. It has also been associated with genitourinary tract and extragenital syndromes.

Case: We present a 14-year-old girl who developed a pelvic abscess secondary to M.

Official American Thoracic Society/Infectious Diseases Society of America/Centers for Disease Control and Prevention Clinical Practice Guidelines: Diagnosis of Tuberculosis in Adults and Children.

Background: Individuals infected with Mycobacterium tuberculosis (Mtb) may develop symptoms and signs of disease (tuberculosis disease) or may have no clinical evidence of disease (latent tuberculosis infection [LTBI]). Tuberculosis disease is a leading cause of infectious disease morbidity and mortality worldwide, yet many questions related to its diagnosis remain.

Methods: A task force supported by the American Thoracic Society, Centers for Disease Control and Prevention, and Infectious Diseases Society of America searched, selected, and synthesized relevant evidence.

Official American Thoracic Society/Infectious Diseases Society of America/Centers for Disease Control and Prevention Clinical Practice Guidelines: Diagnosis of Tuberculosis in Adults and Children.

Background: Individuals infected with Mycobacterium tuberculosis (Mtb) may develop symptoms and signs of disease (tuberculosis disease) or may have no clinical evidence of disease (latent tuberculosis infection [LTBI]). Tuberculosis disease is a leading cause of infectious disease morbidity and mortality worldwide, yet many questions related to its diagnosis remain.

Methods: A task force supported by the American Thoracic Society, Centers for Disease Control and Prevention, and Infectious Diseases Society of America searched, selected, and synthesized relevant evidence.

Mycobacteria.

The immunocompromised host is at increased risk of Mycobacterium tuberculosis complex and nontuberculous mycobacteria infection. Although Mycobacterium tuberculosis complex is a significant mycobacterial pathogen, nontuberculous mycobacteria causes substantial disease in those with suppressed immune responses. Mycobacterial infections can cause significant morbidity and mortality in this patient population, and rapid identification and susceptibility testing of the mycobacterial species is paramount to patient management and outcomes.

Multiclonal methicillin-resistant Staphylococcus aureus (MRSA) outbreak and its control after use of the Veterans Affairs (VA) MRSA bundle in a VA long-term care facility, 2004-2014.

A multiclonal methicillin-resistant Staphylococcus aureus (MRSA) outbreak with 91 infections occurred in our Veterans Affairs (VA) community living center over 46 months. Both similar and unique strains were shown by repetitive polymerase chain reaction to contribute to the outbreak, including 1 strain causing infections over a 33-month period. Most infections were soft tissue infections (67%).

A 66-year-old woman with fever, cough, and a tongue lesion.

A 66-year-old woman presented with acute onset of fever, chills, and productive cough associated with right-sided chest pain. During a recent hospitalization for dyspnea, she had been diagnosed with Coombs-positive autoimmune hemolytic anemia and had been taking a tapering dose of prednisone starting approximately 6 weeks prior to admission. In the interim, her dyspnea had resolved on treatment with steroids.

IFN-γ release assay conversions and reversions. Challenges with serial testing in U.S. health care workers.

Rationale: IFN-γ release assays (IGRAs) including the QuantiFERON-TB gold in-tube test (QFT-GIT) are increasingly used in place of the tuberculin skin test (TST) in surveillance programs for Mycobacterium tuberculosis infection in the United States. However, data on conversions, reversions, and predictive value of QFT in such programs for health care workers (HCWs) are limited.

Objectives: The purpose of this study is to assess long-term reproducibility and conversion and reversion rates of QFT-GIT among HCWs who underwent serial testing at a tertiary care center in the United States.

In vitro activity of amikacin against isolates of Mycobacterium avium complex with proposed MIC breakpoints and finding of a 16S rRNA gene mutation in treated isolates.

Amikacin is a major drug used for the treatment of Mycobacterium avium complex (MAC) disease, but standard laboratory guidelines for susceptibility testing are not available. This study presents in vitro amikacin MICs for 462 consecutive clinical isolates of the MAC using a broth microdilution assay. Approximately 50% of isolates had amikacin MICs of 8 μg/ml, and 86% had MICs of ≤16 μg/ml.

Use of interferon-gamma release assays in a health care worker screening program: experience from a tertiary care centre in the United States.

Background: Interferon-gamma release assays including the QuantiFERON-TB Gold In-Tube test (QFT-GIT [Cellestis Ltd, Australia]) may be used in place of the tuberculin skin test (TST) in surveillance programs for Mycobacterium tuberculosis infection control. However, data on performance and practicality of the QFT-GIT in such programs for health care workers (HCWs) are limited.

Objectives: To assess the performance, practicality and reversion rate of the QFT-GIT among HCWs at a tertiary health care institution in the United States.

Multisite reproducibility of the broth microdilution method for susceptibility testing of Nocardia species.

Antimicrobial susceptibility testing (AST) of clinical isolates of Nocardia is recommended to detect resistance to commonly used antimicrobial agents; such testing is complicated by difficulties in inoculum preparation and test interpretation. In this study, six laboratories performed repetitive broth microdilution testing on single strains of Nocardia brasiliensis, Nocardia cyriacigeorgica, Nocardia farcinica, Nocardia nova, and Nocardia wallacei. For each isolate, a total of 30 microdilution panels from three different lots were tested at most sites.

Clinical and laboratory update on blastomycosis.

Blastomycosis is endemic in regions of North America that border the Great Lakes and the St. Lawrence River, as well as in the Mississippi River and Ohio River basins. Men are affected more often than women and children because men are more likely to participate in activities that put them at risk for exposure to Blastomyces dermatitidis.

Comparison of traditional phenotypic identification methods with partial 5' 16S rRNA gene sequencing for species-level identification of nonfermenting Gram-negative bacilli.

Correct identification of nonfermenting Gram-negative bacilli (NFB) is crucial for patient management. We compared phenotypic identifications of 96 clinical NFB isolates with identifications obtained by 5' 16S rRNA gene sequencing. Sequencing identified 88 isolates (91.

Strong correlation between serum aspergillus galactomannan index and outcome of aspergillosis in patients with hematological cancer: clinical and research implications.

Background: Galactomannan is an Aspergillus-specific polysaccharide released during aspergillosis and is detected by the quantitative serum galactomannan index (GMI) test. Preclinical and preliminary clinical reports have suggested a good correlation between GMI and aspergillosis outcome.

Methods: We reviewed the literature to assess the strength of correlation between GMI and aspergillosis outcome using the kappa correlation coefficient.

Repetitive-sequence-based PCR using the DiversiLab system for identification of Aspergillus species.

Repetitive-sequence-based PCR (rep-PCR) using the DiversiLab system was investigated for identification of Aspergillus. Ninety-five clinical isolates, identified by conventional methods, and five ATCC strains were tested. Sequencing of the internal transcribed spacer (ITS) region (ITS1-5.

Serum Aspergillus galactomannan antigen values strongly correlate with outcome of invasive aspergillosis: a study of 56 patients with hematologic cancer.

Background: Determining the outcome of patients with aspergillosis can be particularly difficult because patients with aspergillosis are at risk for other conditions that mimic this infection. Galactomannan is an Aspergillus-specific antigen released during invasive aspergillosis and is detected by the quantitative serum galactomannan index (GMI) test.

Methods: Using a kappa correlation coefficient test (KCC), the strength of correlation was determined between GMI and survival outcome of aspergillosis among 56 adults with hematologic cancer (90% had myeloma) who underwent serial GMI monitoring until hospital discharge or death.

Immune reconstitution inflammatory syndrome in cancer patients with pulmonary aspergillosis recovering from neutropenia: Proof of principle, description, and clinical and research implications.

Background: Assessing the outcome of patients with invasive pulmonary aspergillosis by using conventional criteria is difficult, particularly when clinical and radiologic worsening coincides with neutrophil recovery. Usually, it is assumed that this deterioration is related to progressive aspergillosis, prompting changes in patient management. However, its temporal relation with neutrophil recovery suggests that it may be caused by an immune reconstitution syndrome (IRIS).

High serum-free light chain levels and their rapid reduction in response to therapy define an aggressive multiple myeloma subtype with poor prognosis.

Serum-free light chain (SFLC) levels are useful for diagnosing nonsecretory myeloma and monitoring response in light-chain-only disease, especially in the presence of renal failure. As part of a tandem autotransplantation trial for newly diagnosed multiple myeloma, SFLC levels were measured at baseline, within 7 days of starting the first cycle, and before both the second induction cycle and the first transplantation. SFLC baseline levels higher than 75 mg/dL (top tertile) identified 33% of 301 patients with higher near-complete response rate (n-CR) to induction therapy (37% vs 20%, P = .

Identification of Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species by repetitive-sequence-based PCR.

The performance of repetitive-sequence-based PCR (rep-PCR) using the DiversiLab system for identification of Coccidioides species, Blastomyces dermatitidis, and Histoplasma capsulatum was assessed by comparing data obtained to colony morphology and microscopic characteristics and to nucleic acid probe results. DNA from cultures of 23 Coccidioides, 24 B. dermatitidis, 24 H.

Teaching pediatric laboratory medicine to pathology residents.

Context: Laboratory data are essential to the medical care of fetuses, infants, children, and adolescents. However, the performance and interpretation of laboratory tests on specimens from these patients, which may constitute a significant component of the workload in general hospitals and integrated health care systems as well as specialized perinatal or pediatric centers, present unique challenges to the clinical pathologist and the laboratory. Therefore, pathology residents should receive training in pediatric laboratory medicine.