A Cervical Smear Scare due to Monsel's Solution: A Case Report

Monsel's solution has been in use since the end of the 19th century for its valuable property of creating hemostasis in minor disruptions of the epithelium. Its styptic effect was first described by Leon Monsel, a pharmacist in the French army, in a letter dated on October 13, 1852. Containing ferric subsulphate, it is used as a topical hemostatic agent in minor procedures such as biopsies in gynecology, proctology, dermatology, otorhinolaryngology and odontology. A 28-year-old nulliparous woman, with a known history of adenomyosis, had presented for sudden heavy intermenstrual vaginal bleeding. Examination revealed a bleeding Nabothian cyst. Monsel's solution application helped stop the bleeding. She returned 3 days later with persistent heavy vaginal bleeding. Examination showed active oozing from the Nabothian cyst. A cervical smear and a human papillomavirus (HPV) swab were taken, and vaginal packing was inserted. The cervical smear result was reported as atypical cells, suspicious for malignancy. Colposcopy performed showed a grade 2 acetowhite lesion, suspicious for cervical intraepithelial neoplasia (CIN) III/microinvasive disease. However, punch biopsies of the cervix revealed only CIN I/koilocytosis. The patient was counselled and subsequently underwent a laser cone biopsy, which showed CIN I with clear margins. The discrepant results between the cervical smear and the cone biopsy prompted a review of the cervical smear and cervical histology; and a relook at the chronology of events. The cytological features observed in the initial cervical smear could be explained by the interference from the Monsel's solution, which was applied just 3 days before the cervical smear. In cases where Monsel's solution has been used for hemostasis, it is best to delay taking a cervical smear or a biopsy for at least 3 weeks as the histologic effect of Monsel's solution may persist for up to that duration of time in tissues.