Investigations

1st investigations to order

pregnancy test

Test
Result
Test

A urinary or blood pregnancy test should be performed in all sexually active women, even if using a method of contraception.

Blood pregnancy test: beta-hCG blood level <5 mIU/mL indicates negative result.

Result

positive or negative

wet mount examination of cervical discharge

Test
Result
Test

Sensitive indicator of cervical inflammation, in the absence of inflammatory vaginitis.[9]

Microscopy is only 50% sensitive for detection of Trichomonas vaginalis; although culture is more sensitive than microscopy, it is less sensitive than nucleic acid amplification tests, which are now considered the gold standard test.[1]​​[20]​​​​

Bacterial vaginosis may be diagnosed by presence of at least three of the four Amsel criteria: 1) adherent white vaginal discharge; 2) clue cells on microscopy (vaginal epithelial cells with distinctive stippled appearance as covered by bacteria); 3) vaginal pH >4.5; 4) 'whiff test' (release of fishy odour following addition of 10% potassium hydroxide solution).[22]

Result

>10 WBCs per high-power field of vaginal fluid (leukorrhoea), trichomonads, clue cells, pH >4.5, fishy amine odour with application of 10% potassium hydroxide

nucleic acid amplification testing (NAAT)

Test
Result
Test

Urine, vaginal swab (self-obtained), cervical swab, or combined with cervical cytology screening. Cervical specimens have the greatest sensitivity, but urinary and some vaginal swabs also have comparable predictive power. Rectal swabs may not be approved by regulatory agencies for use with NAAT.[9]

For Chlamydia trachomatis, Neisseria gonorrhoeae, or Mycoplasma genitalium, the sensitivity and specificity of urine specimens are 93.8% and 100%, respectively, compared with >99% for both parameters from endocervical specimens.[24]​ For Trichomonas vaginalis, the sensitivity and specificity of vaginal or endocervical swabs and urine samples is 88% to 100% and 95% to 100%, respectively.[20]

Result

positive for Chlamydia trachomatis or Neisseria gonorrhoeae or Mycoplasma genitalium orTrichomonas vaginalis

rapid tests (OSOM Trichomonas, AFFIRM VPIII)

Test
Result
Test

Fast and reliable point of care tests with sensitivity >83%, specificity >97%. Results available within 30 minutes for OSOM Trichomonas rapid test and in 45 minutes for AFFIRM VP III.

Result

positive for Trichomonas vaginalis

Thayer-Martin agar cervical culture

Test
Result
Test

For detection of N gonorrhoeae.

Result

growth of pathogen

Gram stain of cervical discharge

Test
Result
Test

For diagnosis of bacterial vaginosis. Nugent score is used, which involves counting bacterial morphocytes.[21]

Result

Lactobacillus morphotype reduced or absent

Investigations to consider

cervical cytology

Test
Result
Test

Not recommended as part of the screening protocol for women at risk of STIs. Routine screening protocols for cervical cytology should be followed.

Inflammatory changes are associated with chlamydial or gonorrhoeal infections but are not specific or sensitive enough for empirical therapy.[1]​​

Result

inflammatory changes

herpes simplex virus (HSV) serology

Test
Result
Test

Increased sensitivity for detection of HSV type 2 compared with culture if no active lesions or presentation of a recurrent infection.[1]​​

Result

presence of antibodies to HSV type 2

HIV serology

Test
Result
Test

Not a cause for cervicitis, but testing should be offered if any other sexually transmitted infection is diagnosed.

Result

negative

hepatitis B and C serologies

Test
Result
Test

Not a cause for cervicitis, but testing should be offered if any other sexually transmitted infection is diagnosed.

Result

negative

rapid plasma reagin testing

Test
Result
Test

Syphilis is not a cause for cervicitis, but testing should be offered if any other sexually transmitted infection is diagnosed.

Result

negative

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