1. STDs
2. Chlamydia
3. Testing

Chlamydia Testing Singapore | Shim Clinic

Chlamydia testing allows you to check for a chlamydia infection after unprotected sex: condom break, slip, or no condom. The urethra, vagina, anus, and throat can be tested in our private & confidential STD clinic.

LABORATORY TESTS

• Chlamydia trachomatis is an intracellular organism, specimens must include epithelial cells and not exudates alone.
• Nucleic acid-based amplification tests (NAAT): most sensitive 90–95%, highly specific, new gold standard; polymerase chain reaction (PCR) can be used to test a range of specimens (urine, urethral, cervical, rectal, pharyngeal).
• Females – cervical or vulvo-vaginal swabs are specimens of choice, followed by first void urine (FVU); males – FVU is as sensitive as urethral swabs; care with inhibitors with urine specimens; storing urine overnight at 40C or freeze-thawing may enhance sensitivity of urine specimens.
• NAATs may be used for conjunctival, pharyngeal and rectal specimens, although currently unlicensed for these sites; rectal swabs should be obtained via proctoscopy.
• Medico legal cases – samples for NAAT should be taken from all the sites where penetration has occurred, a reactive NAAT result must be confirmed using a different NAAT.
• Antigen detection methods – Direct Florescent Antigen (DFA) sensitivity 50–90%; enzyme immunoassay (EIA) poor sensitivity 50–70%, specificity >95%, inexpensive, can be used for large numbers of specimens. FVU or urethral swabs can be used for males, endocervical swabs are preferred for women.
• Cell culture for chlamydia in McCoy cell monolayers, used to be the gold-standard, it is fairly sensitive (70–80%) and 100% specific, requires stringent cold-chain, costly, very expensive, not readily available anymore.
• Giemsa-stained direct smear for the inclusion bodies within infected cells is useful only for ocular infections.
• Serological tests are not useful to diagnose acute chlamydial infections because of cross-reactivity between chlamydial species, high prevalence of chlamydia antibodies in high risk populations, and the unpredictability of serological response and changes in titres of IgM and IgG antibodies in acute uncomplicated infections.

• Chlamydia PCR (polymerase chain reaction) test of the site: urethera, vagina, anus, throat.
• Chlamydia antibodies in the blood suggest on ongoing or previous chronic chlamydia infection.
  “[Chlamydia] IgG serology should not be routinely performed to diagnose acute [Chlamydia] STIs.”
  However:
  • Male
    • “Most of the patients that evidenced CT [Chlamydia trachomatis] infection also evidenced CT[Chlamydia trachomatis]-specific antibodies either in semen or in serum.”
      “Our results support the potential role of CT [Chlamydia trachomatis] in chronic prostatitis, its importance in diagnosis”
      Rubén Darío Motrich, Cecilia Cuffinib, Juan Pablo Mackern Obertia, Mariana Maccionia, Virginia Elena Riveroa. Chlamydia trachomatis occurrence and its impact on sperm quality in chronic prostatitis patients. Journal of Infection Volume 53, Issue 3, September 2006, Pages 175–183
    • “C. trachomatis IgG antibodies in the man of the infertile couple was related to decreased pregnancy rates and to the presence of IgG antibodies in the woman. There was a high prevalence of asymptomatic persistent infections among infertile couples.”
      A. Idahl, J. Boman, U. Kumlin and J.I. Olofsson. Demonstration of Chlamydia trachomatis IgG antibodies in the male partner of the infertile couple is correlated with a reduced likelihood of achieving pregnancy Human Reproduction Vol.19, No.5 pp. 1121–1126, 2004
    • “The presence of serum anti-chlamydial IgG antibodies was demonstrated in 13/42 (30.9%) patients with prostatitis and in 3/36 (8.3%) patients with prostatodynia ( P 0.01). The results suggest that chlamydia may be one of the causative agents of chronic prostatitis.”
      Iwona Ostaszewska, Bozena Zdrodowska-Stefanow, Jerzy Badyda, Katarzyna Pucilo, Jadwiga Trybula and Violetta Bulhak. Chlamydia trachomatis : probable cause of prostatitis. Int J STD AIDS 1 June 1998 vol. 9 no. 6 350-353
    • “Positive rate of IgA and IgG titers in serum and prostatic secretion was higher in cases of chronic prostatitis than that in cases of suspected chronic prostatitis or the normal male group.”
      Tsunekawa T, Kumamoto Y, Kansenshogaku Zasshi. A study of IgA.IgG titers for C. trachomatis in serum and prostatic secretion of chronic prostatitis. The Journal of the Japanese Association for Infectious Diseases [1989, 63(2):130-137]
  • Female
    • “In the work-up for subfertile couples, the combination of patient characteristics with CAT and HSG results gives the best diagnostic performance for the diagnosis of bilateral tubal pathology.”
      K.A. Broeze, B.C. Opmeer, S.F. Coppus, N. Van Geloven, J.E. Den Hartog, J.A. Land, P.J.Q. Van der Linden, E.H.Y. Ng, J.W. Van der Steeg, P. Steures, F. Van der Veen and B.W. Mol. Integration of patient characteristics and the results of Chlamydia antibody testing and hysterosalpingography in the diagnosis of tubal pathology: an individual patient data meta-analysis Hum. Reprod. (2012) 27 (10): 2979-2990.
    • “The risk of developing late complications after chlamydia lower genital tract infection appears low.”
      “In screening programmes, chlamydia antibody testing, as an intermediate marker for potential adverse sequelae, might enable more precise estimates.”
      J.A. Land, J.E.A.M. Van Bergen, S.A. Morre, and M.J. Postma. Epidemiology of Chlamydia trachomatis infection in women and the cost-effectiveness of screening. Hum. Reprod. Update (2010) 16 (2): 189-204.
    • “Pelvic inflammatory disease (PID) and its chronic sequelae are associated with chlamydial IgG antibody formation in serum, and a correlation between the height of antibody titres and the presence of tubal factor subfertility has been established.”
      Land JA, Evers JL. Chlamydia infection and subfertility. Best Practice & Research Clinical Obstetrics & Gynaecology Volume 16, Issue 6 , Pages 901-912, December 2002
    • “The diagnostic work-up to detect tubal pathology in subfertile couples should start with CAT (Chlamydia antibody testing) in couples with relatively good fertility prospects and immediate HSG in couples with relatively poor fertility prospects.”
      Ben W.J Mol, M.D., Ph.D., John A Collins, M.D., Fulco Van Der Veen, M.D., Ph.D., Patrick M.M Bossuyt, Ph.D. Cost-effectiveness of hysterosalpingography, laparoscopy, and Chlamydia antibody testing in subfertile couples. Fertility and Sterility Volume 75, Issue 3, March 2001, Pages 571–580
    • “The discriminative capacity of Chlamydia antibody titers by means of ELISA, microimmunofluorescence, or immunofluorescence in the diagnosis of any tubal pathology is comparable to that of hysterosalpingography (HSG) in the diagnosis of tubal occlusion.”
      Mol BW, Dijkman B, Wertheim P, Lijmer J, van der Veen F, Bossuyt PM. The accuracy of serum chlamydial antibodies in the diagnosis of tubal pathology: a meta-analysis. Fertility and Sterility [1997, 67(6):1031-1037]
    • “C.trachomatis antibody testing is a simple and inexpensive means of predicting pelvic damage and laparoscopic examination may be recommended for patients with high anti-C.trachomatis antibody titres by ELISA.”
      M. Tanikawa, T. Harada, C. Katagiri, Y. Onohara, S. Yoshida and N. Terakawa. Immunology: Chlamydia trachomatis antibody titres by enzyme-linked immunosorbent assay are useful in predicting severity of adnexal adhesion. Hum. Reprod. (1996) 11 (11): 2418-2421.

References

• Chlamydia testing @ Wikipedia