A misleading false-negative result using Neisseria gonorrhoeae opa MGB multiplex PCR assay in patient's rectal sample due to partial mutations of the opa gene

New Microbiol. 2015 Jul;38(3):431-4. Epub 2015 Jul 6.

Abstract

A 53-year-old homosexual man presented at his general practitioner (GP) practice with a suspicion of sexually transmitted infection. Initial NAAT screening was performed for Chlamydia trachomatis and Neisseria gonorrhoeae. The patient was positive for Neisseria gonorrhoeae both for his urine and rectal sample. The subsequent confirmation test for Neisseria gonorrhoeae by a second laboratory was only confirmed for the urine sample and the rectal sample was negative. We report a case of a potential false-negative diagnosis of Neisseria gonorrhoeae due to mutations of DNA sequence in the probe region of opa-MGB assay of the rectal sample. The patient did not suffer any discomfort as diagnosis of Neisseria gonorrhoeae in his urine sample had already led to treatment by prescribing the patient with Ceftriaxone 500 mg IV dissolved in 1 ml lidocaine 2% and 4 mL saline. The patient also received a prescription for Azithromycin (2x500 mg).

Keywords: GP practice; Multiplex PCR; Mutation; Neisseria gonorrhea; Sexually transmitted infections.

Publication types

  • Case Reports

MeSH terms

  • Anti-Bacterial Agents / administration & dosage
  • Bacterial Outer Membrane Proteins / genetics*
  • Chlamydia Infections
  • Diagnostic Errors
  • False Positive Reactions
  • Gonorrhea / diagnosis*
  • Gonorrhea / drug therapy
  • Gonorrhea / microbiology
  • Humans
  • Male
  • Middle Aged
  • Multiplex Polymerase Chain Reaction / methods
  • Mutation*
  • Neisseria gonorrhoeae / genetics
  • Neisseria gonorrhoeae / isolation & purification*
  • Rectum / microbiology*

Substances

  • Anti-Bacterial Agents
  • Bacterial Outer Membrane Proteins
  • Opa protein, Neisseria