Chlamydia is caused by the bacterium Chlamydia trachomatis, one of the most commonly reported sexually transmitted infections worldwide. While often asymptomatic, this bacterial infection can lead to serious reproductive health issues if left untreated. The Pap smear, or Pap test, is a routine screening tool used to look for changes in the cells of the cervix, primarily to detect those that may lead to cervical cancer. This article explains the relationship between Chlamydia infection and the results of a routine cervical screening.
What an Abnormal Pap Smear Result Means
A Pap smear involves collecting cells from the cervix to examine them under a microscope for signs of abnormality. The primary target of this screening is the detection of precancerous changes, or dysplasia, which are most often linked to persistent infection with the Human Papillomavirus (HPV). When a result is reported as “abnormal,” it means the collected cells looked different from healthy, normal cells.
An abnormal result is not a diagnosis of cancer; rather, it indicates the cells show some deviation from the norm, requiring further attention. These changes are classified using terms like Low-Grade Squamous Intraepithelial Lesion (LSIL) or Atypical Squamous Cells of Undetermined Significance (ASCUS). The pathologist notes these cellular variations, which can be caused by various factors, including infection and inflammation. An abnormal reading simply signals that the cervical tissue is reacting to an underlying process.
How Chlamydia Causes Cellular Changes
Chlamydia infection frequently targets the glandular cells of the endocervix, causing a condition known as cervicitis, which is characterized by inflammation in the cervical tissue. The presence of the bacteria triggers a strong immune response, leading to an influx of inflammatory cells and swelling in the surrounding epithelial cells. This cellular reaction is what can cause the Pap smear to be flagged as abnormal.
The changes seen by the pathologist are reactive, meaning they are a temporary response to inflammation rather than true dysplastic growth caused by a virus like HPV. Chlamydia-induced inflammation often results in a classification like ASCUS, where the cause of the cellular change is unclear but frequently inflammatory in nature. The abnormal Pap smear result often reverts to normal once the infection is successfully treated with antibiotics.
While Chlamydia itself does not cause cervical cancer, its presence may act as a cofactor that promotes the persistence of high-risk HPV infection. The chronic inflammation and damage to the cervical lining caused by C. trachomatis may make the tissue more vulnerable to the oncogenic effects of HPV. Identifying and treating the bacterial infection is an important step in resolving the abnormal Pap result and reducing any potential long-term risk.
Treatment and Follow-Up Testing
When a Chlamydia infection is identified or suspected as the cause of an abnormal Pap smear, the immediate step is to treat the bacterial infection with antibiotics.
Treatment Protocol
Standard treatment typically involves a seven-day course of doxycycline (100 milligrams twice per day) or a single, one-gram dose of azithromycin. Abstinence from sexual activity is advised for seven days after treatment completion to ensure the infection is eradicated and prevent transmission. All sexual partners from the previous 60 days must be notified, tested, and treated to prevent reinfection.
Follow-Up Testing
A “Test of Cure” (TOC) to confirm eradication is not routinely recommended for most non-pregnant patients. However, retesting for reinfection is advised approximately three months after treatment due to the high rate of recurrence. Follow-up for the abnormal Pap smear is typically a repeat Pap test within three to twelve months to confirm that cellular changes have resolved. If cellular abnormalities persist despite successful Chlamydia treatment, a colposcopy or further investigation may be necessary to rule out underlying HPV-related issues.