Differential Diagnosis for LSIL in a 24-year-old

Single Most Likely Diagnosis

• Low-grade Squamous Intraepithelial Lesion (LSIL) due to Human Papillomavirus (HPV) infection: This is the most likely diagnosis given the patient's age and the fact that LSIL is often associated with transient HPV infections, which are common in young adults.

Other Likely Diagnoses

• Inflammatory or reactive cellular changes: These can sometimes be misinterpreted as LSIL, especially if there is an underlying inflammatory process or if the specimen is not of optimal quality.
• Atrophic vaginitis: Although less common in a 24-year-old, atrophic changes can mimic LSIL, especially if there is a lack of estrogenization.

Do Not Miss Diagnoses

• High-grade Squamous Intraepithelial Lesion (HSIL): It is crucial not to miss HSIL, as it has a higher potential for progression to invasive cancer. The distinction between LSIL and HSIL can sometimes be subtle, and careful examination is necessary.
• Cervical cancer: Although rare in young adults, cervical cancer can present with abnormal Pap smear results. It is essential to ensure that any abnormal result is thoroughly investigated.

Rare Diagnoses

• Other infectious agents (e.g., herpes simplex virus, Trichomonas vaginalis): While these infections can cause cellular changes, they are less commonly associated with a diagnosis of LSIL.
• Immature metaplasia or other benign conditions: These can sometimes be confused with LSIL but are less likely to be associated with the typical cytological features of LSIL.