Neisseria gonorrhoeae antimicrobial susceptibility in Lilongwe, Malawi, 2007.
BACKGROUND
Malawi adopted syndromic management of sexually transmitted infections in 1993. Based on clinical efficacy and cost, gentamicin 240 mg intramuscularly, and doxycycline 100 mg twice daily x 7 days was selected as the first line regimen to treat urethritis. We sought to establish current laboratory-based Neisseria gonorrhoeae antibiotic susceptibility patterns for Malawi and describe the pattern of susceptibility since syndromic management began.


METHODS
Between May 15 and August 10, 2007, 126 men with urethritis attending the STD clinic at Kamuzu Central Hospital in Lilongwe had history, genital exam, and urethral swabs taken. All were treated with gentamicin and doxycycline in accordance with Malawi guidelines. Gonorrhea was diagnosed by Gram stain and culture. Antimicrobial susceptibility patterns in gonococcal isolates were determined by disk diffusion and E-test minimum inhibitory concentration (MIC) determination and agar dilution MIC determination.


RESULTS
One hundred six isolates were cultured, and MICs were determined for 100. High levels of resistance to tetracycline and penicillin were observed, but isolates were uniformly susceptible to both gentamicin and ciprofloxacin. Susceptibility patterns identified by the agar dilution MIC and E-test MIC agreed.


CONCLUSIONS
The most recent study continues the trend of high susceptibility of gonococcal isolates to gentamicin in Malawi after 14 years of use and suggests agar dilution MICs may be substituted with the simpler E-test methods in future susceptibility testing. However because of the lack of susceptibility criteria for aminoglycosides for N. gonorrhoeae and the difficulty obtaining clinical/in vitro correlates in this setting, caution should be exercised in using these data for modifying treatment regimens.
Brown
Lillian B
LB
Division of Infectious Diseases, University of North Carolina-Chapel Hill, Chapel Hill, NC 27599, USA. lbbrown@med.unc.edu
Krysiak
Robert
R
Kamanga
Gift
G
Mapanje
Clemente
C
Kanyamula
Happiness
H
Banda
Blessings
B
Mhango
Chisale
C
Hoffman
Mariah
M
Kamwendo
Debbie
D
Hobbs
Marcia
M
Hosseinipour
Mina C
MC
Martinson
Francis
F
Cohen
Myron S
MS
Hoffman
Irving F
IF
D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D004318:Doxycycline / Q000494:pharmacology / Q000627:therapeutic use; D005839:Gentamicins / Q000494:pharmacology* / Q000627:therapeutic use; D006069:Gonorrhea / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D006801:Humans; D008295:Malawi; D008297:Male; D008826:Microbial Sensitivity Tests / Q000379:methods; D009344:Neisseria gonorrhoeae / Q000187:drug effects / Q000302:isolation & purification; D013577:Syndrome; D014526:Urethritis / Q000188:drug therapy / Q000382:microbiology
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D004318:Doxycycline