infectious diseases
Chlamydia and Mycoplasmal Mucosal Infections
Diagnosis of Chlamydia
Nucleic acid–based tests of cervical, urethral, pharyngeal, or rectal exudate or urine Chlamydial or mycoplasmal infection is suspected in patients with symptoms of urethritis, salpingitis, cervicitis, or unexplained proctitis, but similar symptoms can also result from gonococcal infection. If clinical evidence for urethritis is uncertain, the Centers for Disease Control and Prevention (CDC)2021 Sexually Transmitted Infections Treatment Guidelinesstate that urethritis can be documented by any of the following: Mucoid, mucopurulent, or purulent discharge observed during examination ≥ 10 white blood cells per high-power field in spun first-void urine A positive leukocyte esterase test on first-void urine ≥ 2 white blood cells per oil immersion field in Gram-stained urethral secretions Samples of cervical or vaginal specimens or male urethral or rectal exudates are obtained to check for chlamydiae. Urine samples can be used as an alternative to cervical or urethral specimens. Throat and rectal swabs are needed to test for infection at those sites. Commercially available nucleic acid amplification tests (NAATs) are highly sensitive and specific for chlamydia and can also be done on self-collected urine or vaginal specimens, eliminating the need for doing an uncomfortable swab of the urethra or cervix. Point-of-care NAAT platforms are available and can provide same-visit results. In general, samples from the throat and rectum should be tested only in laboratories that have verified the use of these tests for those anatomic sites. Because other STIs (particularly gonococcal infection) often coexist, patients who have symptomatic urethritis should also be Diagnosis . All patients who receive a diagnosis of gonorrhea or chlamydia should be tested for other STIs, including syphilis and HIV. Mycoplasma genitaliumcan be detected using commercial NAAT assays, but those may not be widely available. In the US, confirmed cases of chlamydial infection, gonorrhea, and syphilis must be reported to the public health system. Testing urine or self-collected vaginal swabs using NAAT is especially useful for screening asymptomatic people at high risk of STIs because genital examination is not necessary. Screening recommendations vary by sex, age, sexual practices, and setting. The following are based on theCDC's Sexually Transmitted Infections (STI) Treatment Guidelines, 2021. Womenare screened annually if they are sexually active and < 25 years of age or if they are ≥ 25 years of age, sexually active, and have one or more of the following risk factors: Have a history of a prior STI Engage in high-risk sexual behavior (eg, have a new sex partner or multiple sex partners; engage in sex work; or use condoms inconsistently when not in a mutually monogamous relationship) Have a partner who has an STI or engages in high-risk behavior (eg, a sex partner who has concurrent partners) Have a history of incarceration Pregnant women who are < 25 years or who are ≥ 25 years with one or more of the risk factors are screened during their first prenatal visit and again during their 3rd trimester if risk remains high. The American College of Obstetrics and Gynecology (ACOG) recommends that all pregnant women be tested for chlamydia early in pregnancy, with a repeat test in the 3rd trimester for women with risk factors. It recommends testing for gonorrhea in pregnant women ≤ 25 years and for those living in an area where gonorrhea is common. (SeeACOG: Routine Tests During Pregnancy.) Heterosexually active menare not routinely screened except for those in clinical settings with a high prevalence of chlamydial infection (eg, adolescent clinics, STI clinics, correctional facilities). Men who have sex with menare screened at least annually if they have been sexually active within the previous year (for insertive intercourse, urine screen; for receptive intercourse, rectal swab; and for oral intercourse, pharyngeal swab), regardless of condom use. Those at increased risk (eg, with HIV infection, receive preexposure prophylaxis with antiretrovirals, have multiple sex partners, or whose partner has multiple partners) should be screened more frequently, at 3 to 6-month intervals. Transgender and gender diverse peopleare screened if they are sexually active on the basis of sexual practices and anatomy (eg, annual screening for all people with a cervix who are < 25 years old; if ≥ 25 years old, people with a cervix should be screened annually if at increased risk; rectal swab based on reported sexual behaviors and exposure). (See also the US Preventive Services Task Force’s summary of recommendations regardingscreening for chlamydial infection.) 