Menzies Weekly Seminar - “A mythbusters approach to STI ‘false positives’: wrap up, and directions for translation”

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Presenter:  Professor Phil Giffard, Head of Laboratory Science, Menzies School of Health Research

Date: Feb 27, 2018

Time: 11:00am to 11:30am

Contact person:  Menzies Communications Team
T: 8946 8658

Location:  JMB Auditorium - (also available on WebEx)

Abstract: A positive diagnostic test for a sexually transmitted infection in a urogenital tract (UGT) specimen in a young child is regarded as indicative of sexual abuse and will trigger an investigation as per guidelines. However, the post-test probability of abuse is dependent on both the probability of a positive test in the absence of abuse as well as and the prevalence of abuse. Neither of these parameters are well understood. This is a difficult situation, especially in the Northern Territory, where on one hand an incorrect interpretation of a positive test will result in an investigation which maybe groundless, or on the other hand leave a child at risk remaining in a dangerous situation. In this presentation, a series of studies is described. These address mechanisms that have at times been identified by front line clinicians as conceivable causes of positive Chlamydia trachomatis tests in the absence of what is usually understood as sexual contact i.e. “false positives”. The mechanisms encompass specimen contamination and autoinoculation of the UGT from ocular infection. The results provide numerical boundaries for false positive probabilities, and define translation measures that can both reduce the probability of false positives, and provide additional surveillance data that can enhance the interpretation of positive tests.

Biography: Phil Giffard is Head of Laboratory Science at the Menzies School of Health Research, and works in the Menzies Divisions of Education and Research Support, and Global and Tropical Health. He is also Professor of Medical Laboratory Science in the College of Health and Human Sciences at Charles Darwin University. Read more on the Website.

  • The Menzies seminars are free of charge and open to the general public
  • The presentations will be 20 minutes with 10 minutes for questions.
  • Please feel free to forward this notice to your colleagues and associates

WebEx - Menzies Seminar Series
Every Tuesday, from Tuesday, February 13, 2018, to Tuesday, December 11, 2018
Meeting number: 577 077 961
Meeting password: F5fSNYit
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