One of the key principles of good specimen collection is to avoid introduction of colonizing bacteria surrounding the site of infection or on the skin or mucous membranes near the infectious site. A relatively recently introduced type of swab, the flocked swab, has proved to be superior to fiber swabs for collection of nasopharyngeal samples for detection of respiratory viruses, but there were no significant differences between flocked and rayon swabs when throat cultures were evaluated. For abscess contents, body fluids, and other fluid collections below the skin, aspirates obtained through disinfected intact skin are preferred over swabs. Expectorated sputum is the best sample for diagnosis of pneumonia, a disease of the distal lung alveolar spaces. Urine can be collected by midstream collection, catheterization, cystoscopic collection, or suprapubic aspiration. Urine specimens should be transported to the laboratory immediately and processed within 2 h of collection. Testing more than one stool for bacterial pathogens is usually not productive. Fresh stool should be examined visually, and the areas showing blood, pus, or mucus should be sampled preferentially. In spite of acceptable labeling, some specimen collection sites, transport containers, or transport conditions render the specimen unacceptable for processing. Although blood has not yet been used widely for detection of bacteria using nucleic acid amplification (NAA) tests or hybridization, such tests are in development. Swabs should be transported to the laboratory in special media.

Specimen Collection, Transport, and Processing: Bacteriology

Microbiota of male genital tract: impact on the health of man and his partner.

Molecular detection of potential sexually transmitted pathogens in semen and urine specimens of infertile and fertile males.

Evaluation of Seeplex® STD6 ACE Detection kit for the diagnosis of six bacterial sexually transmitted infections

In this study, we performed an evaluation of the new CE-marked multiplex real-time AmpliSens N.gonorrhoeae/C.trachomatis/M.genitalium/T.vaginalis-MULTIPRIME-FRT PCR assay compared to APTIMA tests, i.e., APTIMA COMBO 2 assay, APTIMA Trichomonas vaginalis assay (FDA-approved), and two different APTIMA Mycoplasma genitalium assays (research use only; one of them only used for discrepancy analysis). Vaginal swabs (n = 209) and first-void urine (FVU) specimens from females (n = 498) and males (n = 554), consecutive attendees (n = 1261) at a dermatovenerological clinic in Sweden, were examined. The sensitivity of the AmpliSens PCR assay for detection of C. trachomatis (6.3% prevalence), M. genitalium (5.7% prevalence), N. gonorrhoeae (0.3% prevalence), and T. vaginalis (0.08% prevalence) was 97.5% (95% confidence interval (CI): 91.2-99.6%), 81.9% (95% CI: 70.7-89.7%), 100% (95% CI: 40.2-100%) and 100% (95% CI: 16.5-100%), respectively. The specificity of the AmpliSens PCR assay was 100% (95% CI: 99.6-100%) for all agents. The analytical sensitivity and specificity for N. gonorrhoeae detection was excellent, i.e., 55 international gonococcal strains detected and 135 isolates of 13 non-gonococcal Neisseria species were negative. In conclusion, the multiplex real-time AmpliSens N.gonorrhoeae/C.trachomatis/M.genitalium/T.vaginalis-MULTIPRIME-FRT PCR assay demonstrated high sensitivity and excellent specificity for the detection of C. trachomatis, N. gonorrhoeae, and T. vaginalis, and excellent specificity but suboptimal sensitivity for M. genitalium detection.

Evaluation of the new AmpliSens multiplex real-time PCR assay for simultaneous detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, and Trichomonas vaginalis.

We developed a multiplex PCR (mPCR) assay to simultaneously detect Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Ureaplasma urealyticum, Corynebacterium spp. and seudomona aeruginosa. This method employs a single tube and multiple specific primers which yield 200, 281, 346, 423, 542, and 1,427 bp PCR products, respectively. All the PCR products were easily detected by agarose gel electrophoresis and were sequenced to confirm the specificity of the reactions. To test this method, DNA extracted from urine samples was collected from 96 sexually transmitted disease or prostatitis patients at a local hospital clinical center, and were subjected to the mPCR assay. The resulting amplicons were cloned and sequenced to exactly match the sequences of known pathogenic isolates. N. gonorrhoeae and Corynebacterium spp. were the most frequently observed pathogens found in the STDs and prostatitis patients, respectively. Unexpectedly, P. aeruginosa was also detected in some of the STD and prostatitis samples. More than one pathogen species was found in 10% and 80.7% of STD and prostatitis samples, respectively, indicating that STD and prostatitis patients may have other undiagnosed and associates. The sensitivity of the assay was determined by sing purified DNA from six pathogenic laboratory strains and revealed that this technique could detect pathogenic DNA at concentrations ranging from 0.018 to 1.899 pg/ul. Moreover, the specificities of this assay were found to be highly efficient. Thus, this mPCR assay may be useful for the rapid diagnosis of causative infectious STDs and prostatitis. useful for the infectious STDs and prostatitis.

Rapid one step detection of pathogenic bacteria in urine with sexually transmitted disease (STD) and prostatitis patient by multiplex PCR assay (mPCR).

Ji Min Chung

Papers

Rapid one step detection of pathogenic bacteria in urine with sexually transmitted disease (STD) and prostatitis patient by multiplex PCR assay (mPCR).