Neisseria gonorrhoeae
From IDWiki
Background
- Causes gonorrhea
Microbiology
- Gram-negative diplococcus
- Resistance
- MDR gonorrhea: resistance to one of azithromycin or a cephalosporin
- XDR if resistance to both azithromycin and a cephalosporin
Epidemiology
- Resistance
- About 50% resistance to fluoroquinolones
- Rates of MDR gonorrhea is increasing in Canada, mostly driven by azithromycin resistance
- XDR gonorrhea is still rare in Canada 1
Mechanisms of Resistance
- β-lactamases, most commonly a TEM-1-type contained on a PcR plasmid
- Altered penicillin-binding protein PBP-2, encoded by penA
- Altered or downregulated porins, encoded by penB
- Increased efflux pump, encoded by mtr
Clinical Manifestations
Anorectal gonorrhea
- Often asymptomatic
- Can cause anorectal pain, discharge, and pruritis
- Anal intercourse not required, especially in women
Disseminated gonococcal infection
- Classically presents with tenosynovitis (often of wrists) or frank arthritis, with pustular lesions
- Diagnosed with genital testing for gonorrhea, ± blood cultures or arthrocentesis
Differential Diagnosis
- Other causes of urethritis or septic arthritis
Management
- Anogenital and pharyngeal infection in people ≥9 years of age
- First-line: ceftriaxone 250 mg IM once plus azithromycin 1 g PO once
- Second-line: gentamicin 240 mg IM once (in 2 doses) plus azithromycin 2 g PO once
- Second-line: ciprofloxacin 500 mg PO once plus azithromycin 2 g PO once
- Disseminated gonococcal infection
- Arthritis: ceftriaxone 2 g IV q24h for 7 days, plus azithromycin 1 g PO once
- Meningitis: ceftriaxone 2 g IV q24h for 10-14 days, plus azithromycin 1 g PO once
- Endocarditis: ceftriaxone 2 g IV q24h for 28 days, plus azithromycin 1 g PO once
- Ophthalmia: ceftriaxone 2 g IV once, plus azithromycin 1 g PO once
- Repeat screening at 6 months
Test of Cure
- Done at 3 to 7 days if by culture or 14 to 21 days if NAAT
- Indications include:
- Pharyngeal infection
- Persistent signs or symptoms
- Treated without ceftriaxone
- Treated with fluoroquinolone, without susceptibility testing
- Epidemiologic link to a resistant case
- Documented microbiologic resistance
- Epidemiologic link to treatment failure
- Previous treatment failure
- Uncertain adherence to treatment
- Reexposure to untreated partener
- Pregnancy
- Disseminated gonococcal infection
- Pediatric patient
- Pelvic inflammatory disease with documented gonorrhea
- Therapeutic abortion (increased risk of developing PID)
Further Reading
References
- ^ I Martin, P Sawatzky, V Allen, B Lefebvre, LMN Hoang, P Naidu, J Minion, P Van Caeseele, D Haldane, RR Gad, G Zahariadis, A Corriveau, G German, K Tomas, MR Mulvey. Multidrug-resistant and extensively drug-resistant Neisseria gonorrhoeae in Canada, 2012–2016. Canada Communicable Disease Report. 2019;45(2/3):45-53. doi:10.14745/ccdr.v45i23a01.
