Metronidazole resistance in Trichomonas vaginalis from highland women in Papua New Guinea.
BACKGROUND
The prevalence of the sexually transmissible protozoan parasite Trichomonas vaginalis in the highlands of Papua New Guinea (PNG) has been reported to be as high as 46% and although not previously studied in Papua New Guinea, clinical resistance against metronidazole (Mz), the drug most commonly used to treat trichomoniasis, is well documented worldwide. This study was primarily aimed at assessing resistance to Mz in T. vaginalis strains from the Goroka region.


METHODS
Consenting patients presenting at the Goroka Base Hospital Sexually Transmitted Diseases (STD) Clinic and local women were asked to provide two vaginal swabs: one for culturing of the parasite; and one for polymerase chain reaction detection of T. vaginalis, Chlamydia trachomatis and Neisseria gonorrhoeae. T. vaginalis isolates were assayed for Mz susceptibility and a selection was genotyped.


RESULTS
The prevalence of T. vaginalis was determined to be 32.9% by culture and polymerase chain reaction of swabs among 82 local women and patients from the STD clinic. An unexpectedly high level of in vitro Mz resistance was determined with 17.4% of isolates displaying unexpectedly high resistance to Mz. The ability to identify isolates of T. vaginalis by genotyping was confirmed and the results revealed a more homogeneous T. vaginalis population in Papua New Guinea compared with isolates from elsewhere.


CONCLUSIONS
T. vaginalis is highly prevalent in the Goroka region and in vitro Mz resistance data suggest that clinical resistance may become an issue.
Upcroft
Jacqueline A
JA
Queensland Institute of Medical Research, The Bancroft Centre, 300 Herston Road, Brisbane, Qld 4006, Australia. Jacqui.Upcroft@qimr.edu.au
Dunn
Linda A
LA
Wal
Tilda
T
Tabrizi
Sepehr
S
Delgadillo-Correa
Maria G
MG
Johnson
Patricia J
PJ
Garland
Suzanne
S
Siba
Peter
P
Upcroft
Peter
P
D000293:Adolescent; D000328:Adult; D000981:Antiprotozoal Agents / Q000008:administration & dosage*; D016054:DNA, Protozoan / Q000032:analysis; D004352:Drug Resistance, Microbial; D005260:Female; D006801:Humans; D008795:Metronidazole / Q000008:administration & dosage*; D008875:Middle Aged; D010219:Papua New Guinea / Q000453:epidemiology; D021261:Parasitic Sensitivity Tests; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012725:Sexual Behavior / Q000706:statistics & numerical data; D014245:Trichomonas Infections / Q000188:drug therapy* / Q000453:epidemiology*; D014246:Trichomonas vaginalis / Q000187:drug effects*; D016387:Women's Health
D000981:Antiprotozoal Agents; D016054:DNA, Protozoan; D008795:Metronidazole