Evaluation of a membrane hybridization array for detection of Mycobacterium tuberculosis complex and resistance to isoniazid and rifampin in sputum specimens, mycobacterial liquid cultures, and clinical isolates.

The gold standard of antituberculosis susceptibility testing is based on culture method which takes weeks. Rapid detection of resistance to isoniazid (INH) and rifampin (RIF) to avoid inappropriate regimens and to prevent transmission of resistant strains are important. A membrane array (BluePoint MTBDR) was developed to identify Mycobacterium tuberculosis complex (MTBC) and the genetic mutations responsible for resistance to RIF and INH.

Oligonucleotide Array and VITEK Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry in Species Identification of Blood Yeast Isolates.

We evaluated matrix-assisted laser desorption ionization time-of-flight mass spectrometry using VITEK MS (IVD database) and an oligonucleotide array based on the internal transcribed spacer-1 (ITS-1) and ITS-2 sequences of rRNA genes for the identification of spp. from blood cultures. Five-hundred and twelve consecutive bloodstream yeast isolates were collected daily and initially identified by the phenotypic automated method (VITEK YBC or VITEK2 YST card).

A DNA dot hybridization model for molecular diagnosis of parasitic keratitis.

Purpose: Developing a DNA dot hybridization model for diagnosing parasitic keratitis.

Methods: Newly designed oligonucleotide probes for detecting and microsporidia were tested with target reference strains of (n = 20) and microsporidia (n = 3), and non-target microorganisms, including bacteria (n = 20) and fungi (n = 20). These probes, which had passed the preliminary tests, were then assembled as a parasite dot hybridization (PDH) model for assessing 33 clinical samples from patients with clinically suspected and microsporidia keratitis, including eight positives for , 13 positives for microsporidia, and 12 negatives for both pathogens.

Identification of Staphylococcus spp. and detection of mecA by an oligonucleotide array.

Phenotypic identification of coagulase-negative staphylococci (CoNS) is difficult and many staphylococcal species carry mecA. This study developed an array that was able to detect mecA and identify 30 staphylococcal species by targeting the internal transcribed spacer regions. A total of 129 target reference strains (30 species) and 434 clinical isolates of staphylococci were analyzed.

A Multiplex Dot Hybridization Assay For Detection and Differentiation of Acanthamoeba and Herpes Keratitis.

Purpose: We verified a multiplex dot hybridization (MDH) assay for the rapid detection and differentiation of Acanthamoeba keratitis (AK) and herpes simplex keratitis (HSK).

Methods: Molecular detection of Acanthamoeba and herpes simplex virus in corneal scrapes was performed with the MDH assay and standard diagnostic methods. The experimental group included corneal scrapes (n = 33) from patients with culture- or pathology-confirmed AK (n = 15) and real-time PCR-confirmed HSK (n = 16).

Multiple Brain Abscesses Due to Aspergillus Fumigatus in a Patient With Liver Cirrhosis: A Case Report.

Invasive cerebral aspergillosis always developed in immunocompromised host. Early diagnosis may save life in this critical condition; however, it is difficult to reach. Herein, we presented an unusual case of invasive cerebral aspergillosis in a cirrhotic patient.

Bacterial Bioburden Decrease in Orthokeratology Lens Storage Cases After Forewarning: Assessment by the DNA Dot Hybridization Assay.

Background: The aim of this study was to measure the changes in the bacterial bioburden in orthokeratology (OK) lens storage cases using the DNA dot hybridization assay (DHA) after forewarning patients about their bacterial contamination severity.

Methods: Thirty-one OK lens wearers were prospectively enrolled in this study. Dot hybridization assay was used for serial measurements of bacterial bioburden in OK storage cases after lenses had been soaked for approximately 6 hr.

Optimization of the score cutoff value for routine identification of Staphylococcus species by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry.

Staphylococcus species are important pathogens. We evaluated 2 score cutoffs (2.0 and 1.

A DNA dot hybridization model for assessment of bacterial bioburden in orthokeratology lens storage cases.

Purpose: The aim of this study was to evaluate a DNA dot hybridization assay (DHA) for assessing bacterial bioburden in orthokeratology lens (OK) storage cases.

Methods: Forty-one OK wearers participated in this study. The dot hybridization assay was used to assess the bacterial bioburden of OK after removal and 6-hour soaking in a storage case.

Rapid detection of dermatophytes and Candida albicans in onychomycosis specimens by an oligonucleotide array.

Background: Onychomycosis is a fungal infection of nails, leading to the gradual destruction of the nail plate. Treatment of onychomycosis may need long-time oral antifungal therapy that can have potential side effects, thus accurate diagnosis of the disease before treatment is important. Culture for diagnosis of onychomycosis is time-consuming and has high false-negative rates.

Acute meningitis caused by Cladosporium sphaerospermum.

Phaeohyphomycosis of the central nervous system is rare but typically associated with high mortality. Treatment has not been standardized, but the combination of antifungal chemotherapy with surgical debridement is recommended. We report a 73-year-old, retired, male timber merchant with acute meningitis caused by Cladosporium sphaerospermum.

Development of a loop-mediated isothermal amplification method for rapid detection of pigeon circovirus.

There are no effective antiviral treatments for pigeon circovirus (PiCV); thus, rapid diagnosis is critical for effective control of the disease caused by this virus. The recent development of a novel LAMP technique that amplifies nucleic acids rapidly with high specificity and sensitivity under isothermal conditions has overcome some of the deficiencies of nucleic-acid-based diagnostic tests. We established a LAMP method for rapid detection of PiCV using two pairs of primers that were designed from PiCV and compared its sensitivity and specificity with that of PCR.

Acrophialophora fusispora brain abscess in a patient with acquired immunodeficiency syndrome: a case report and review of the literature.

We reported a fatal case of brain abscess caused by Acrophialophora fusispora in a patient with acquired immunodeficiency syndrome. Identification of the fungus was based on microscopic morphology and sequence analyses of the internal transcribed spacer 1 (ITS1) and 2 (ITS2) of ribosomal RNA gene from the isolate recovered from brain abscess. Four published cases were reviewed as well.

Evaluation of a membrane array for detection of Mycobacterium tuberculosis complex and nontuberculous mycobacteria in positive liquid cultures.

Molecular identification of mycobacteria in positive Mycobacteria Growth Indicator Tube (MGIT) cultures can accelerate mycobacterial diagnosis. A membrane hybridization array (Blue Point) was evaluated for this purpose in 284 positive MGIT cultures. Discrepant results were resolved by testing with the GenoType Mycobacterium kit, TBc ID test, sequencing of the 16S rRNA gene and internal transcribed spacer.

A highly sensitive method for molecular diagnosis of fungal keratitis: a dot hybridization assay.

Purpose: Fungal keratitis (FK) is an important cause of ocular morbidity, especially for people living in the agricultural communities of the developing world. Current diagnostic methods may lack sensitivity (direct microscopy) or are time consuming (culture). The aim of this study was to develop a dot hybridization assay for sensitive and rapid diagnosis of FK.

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry and database for identification of Legionella species.

More than 20 species of Legionella have been identified in relation to human infections. Rapid detection and identification of Legionella isolates is clinically useful to differentiate between infection and contamination and to determine treatment regimens. We explored the use of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) Biotyper system (Bruker Daltonik GmbH, Bremen, Germany) for the identification of Legionella species.

Identification of lethal Aspergillus at early growth stages based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Delayed and incorrect diagnoses are potential risk factors leading to high mortality of invasive aspergillosis (IA). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to acquire a wide mass spectral range and characterize the early process of asexual sporulation of lethal IA pathogens recovered on agar plates. Proteins were extracted using trifluoroacetic acid and soft ionized using an ultraviolet laser with the assistance of ferulic acid.

Rapid identification of allergenic and pathogenic molds in environmental air by an oligonucleotide array.

Background: Airborne fungi play an important role in causing allergy and infections in susceptible people. Identification of these fungi, based on morphological characteristics, is time-consuming, expertise-demanding, and could be inaccurate.

Methods: We developed an oligonucleotide array that could accurately identify 21 important airborne fungi (13 genera) that may cause adverse health problems.

Evaluation of the Bactec MGIT 960 system in combination with the MGIT TBc identification test for detection of Mycobacterium tuberculosis complex in respiratory specimens.

The sensitivity and specificity of the MGIT TBc identification (TBc ID) test for Mycobacterium tuberculosis complex (MTC) detection in positive Bactec MGIT cultures were 95.2% and 99.2%, respectively.

Evaluation of the Cobas TaqMan MTB test for direct detection of Mycobacterium tuberculosis complex in respiratory specimens.

The Cobas TaqMan MTB test, based on real-time PCR technology, was evaluated for direct detection of Mycobacterium tuberculosis complex (MTBC) in respiratory specimens. A total of 1,093 samples from 446 patients, including 118 acid-fast smear-positive and 975 acid-fast smear-negative specimens, were investigated. Diagnostic cultures performed with 7H11 agar, Löwenstein-Jensen medium, and the Bactec MGIT 960 system were considered the reference methods.

Electro-microchip DNA-biosensor for bacteria detection.

This paper presents a bacteria biosensor based on DNA hybridization detection with an electro-microchip transducer. Acinetobacter baumannii was chosen as DNA sample source, because the occurrence of bacteremia caused by Acinetobacter baumannii is high in hospitals worldwide. Our strategy is based on DNA hybridization of PCR amplified bacteria DNA with biotin labelled primers and detection enhancement using gold-streptavidin nanoparticles and Ag(+)-hydroquinone solution.

Clinical manifestations, antimicrobial therapy, and prognostic factors of monomicrobial Acinetobacter baumannii complex bacteremia.

Objectives: Bacteremia due to Acinetobacter baumannii complex (ABC), which composed of four genomic species (gen. sp.), is a serious and potentially fatal condition.

Identification of clinically important anaerobic bacteria by an oligonucleotide array.

Anaerobic bacteria can cause a wide variety of infections, and some of these infections can be serious. Conventional identification methods based on biochemical tests are often lengthy and can produce inconclusive results. An oligonucleotide array based on the 16S-23S rRNA intergenic spacer (ITS) sequences was developed to identify 28 species of anaerobic bacteria and Veillonella.

Identification of non-fermenting Gram-negative bacteria of clinical importance by an oligonucleotide array.

Many species of non-fermenting Gram-negative bacilli (non-fermenters) are important opportunistic and nosocomial pathogens. Identification of most species of non-fermenters by phenotypic characteristics can be difficult. In this study, an oligonucleotide array was developed to identify 38 species of clinically relevant non-fermenters.