Rapid determination of lymphogranuloma venereum serovars of Chlamydia trachomatis by quantitative high-resolution melt analysis (HRMA).

A quantitative high-resolution melt analysis assay was developed to differentiate lymphogranuloma venereum-causing serovars of Chlamydia trachomatis (L1 to L3) from other C. trachomatis serovars (D to K). The detection limit of this assay is approximately 10 copies per reaction, comparable to the limits of other quantitative-PCR-based methods.

Anorectal lymphogranuloma venereum in a Melbourne man.

We report the first case of anorectal lymphogranuloma venereum (LGV) in a man who has sex with men (MSM) in Australia in the setting of the recent emergence of LGV among MSM in Europe and the USA. A 33-year-old man presented with a 2 month history of mild external anal discomfort. He gave a history of unprotected receptive and insertive anal intercourse with one partner in Europe during the preceding 6 months. No symptoms suggested proctitis and examination revealed two small anal fissures. An anal swab was positive for Chlamydia trachomatis; investigation for other STIs including HIV were negative. On review 6 days later, he was investigated and treated presumptively for LGV. The LGV diagnosis was confirmed by identifying the L2 serovar of C. trachomatis using a genotype test on the original anal specimen. This case is in keeping with the more recent reports of LGV from Europe, and has demonstrated the need for a high index of suspicion for asymptomatic or minimally symptomatic anorectal LGV.

Molecular tests can allow confirmation of invasive meningococcal disease when isolates yield atypical maltose, glucose or gamma-glutamyl peptidase test results.

Analysis of atypical meningococci from invasive disease that either (i) did not produce acid from maltose and glucose or (ii) were gamma-glutamyl peptidase test negative for porA and porB DNA variable region (VR) type, multilocus sequence type, and for presence of capsule transport gene ctrA, conclusively demonstrated that these are Neisseria meningitidis.

Prospective study of a real-time PCR that is highly sensitive, specific, and clinically useful for diagnosis of meningococcal disease in children.

Due to the early administration of antibiotics, meningococcal disease is increasingly difficult to diagnose by culturing. Laboratory studies have shown PCR to be sensitive and specific, but there have been few clinical studies. The objectives of this study were to determine the diagnostic accuracy and clinical usefulness of meningococcal PCR through a prospective comparison of real-time PCR, nested PCR, and standard culturing of blood and cerebrospinal fluid (CSF). The setting was a tertiary-care pediatric hospital in Australia, and the participants were 118 children admitted with possible septicemia or meningitis. The main outcome measures-sensitivity, specificity, and positive and negative predictive values-were compared to a "gold standard " fulfilling clinical and laboratory criteria. For 24 cases of meningococcal disease diagnosed by the gold standard, culturing of blood or CSF was positive for 15 (63%), nested PCR was positive for 21 (88%), and real-time PCR was positive for 23 (96%). The sensitivity, specificity, and positive and negative predictive values of real-time PCR (the most sensitive test) for all specimens were, respectively, 96% (95% confidence interval, 79 to 99%), 100% (95% confidence interval, 96 to 100%), 100% (95% confidence interval, 85 to 100%), and 99% (95% confidence interval, 94 to 100%). Of 54 patients with suspected meningococcal disease at admission, 23 had positive PCR results. Only one PCR specimen was positive in a patient thought unlikely to have meningococcal disease at admission. Blood PCR remained positive for 33% of patients tested at up to 72 h. Real-time PCR has high positive and negative predictive values in this clinical setting, with better confirmation of cases than nested PCR. Targeting patients for PCR based on admission criteria appears to be practical, and the test may remain useful for several days after the start of antibiotic administration.