Topical disinfectant Potassium Permanganate causes accidental severe ocular Injury- case report

A 6‑year‑old girl was brought by her father with severe pain, redness, and swelling of right eye. The child opened the box of KMnO4 crystal which his father was using for his acute eczema, while playing and accidentally the loose crystals fell inside her eye. Her vitals were stable with no signs of systemic toxicity. Brown staining was observed over the tongue and neck. Copious irrigation of the eye was done with a balanced salt solution for 30 mins. Balanced saline solution is a sterile cleansing solution that provides the cells with water and inorganic ions while maintaining a physiological pH and osmotic pressure. The loose impacted crystals were removed from the inferior fornix with the help of sterile cotton buds. The staining of neck and tongue was cleaned with normal saline.

After removal of the debris, her visual acuity was 6/24. Slit‑lamp examination revealed stained and congested conjunctival mucosa. According to Dua classification, there was more than 30% of conjunctival involvement and more than 3‑6 clock hours of limbal involvement (Grade III). The patient was put on 0.5% moxifloxacin eye drops 4 times a day, 1% prednisolone eye drops every 2 hours for the initial 10 days to reduce inflammation, and lubricant eye drop hourly. Along with this, the patient also received tablet vitamin C 500 mg three times a day.

Gradually, all KMnO4 stains had disappeared. The child started showing improvement but her ocular movements were restricted due to pseudomembrane formation between globe and lid margin. After 7 days of injury, the pseudomembrane was removed under general anesthesia following which there was healing of conjunctiva. After 4 weeks of treatment corneal edema subsided with complete epithelialization of conjunctiva with visual acuity 6/6.

Chemical injuries due to potassium permanganate are rarely reported. It is a powerful caustic chemical that leads to coagulative necrosis of tissue. It can cause permanent loss of vision rarely.

Immediate management of such injuries is important as it prevents complications and improves the outcome. The mainstay of treatment is immediate and adequate decontamination. The most ideal fluid is ringer lactate as its osmolarity is similar to aqueous humour. In acute stages, topical steroid plays an important role in controlling inflammation. If required, topical antibiotics are given in order to prevent secondary infection. In severe cases, where there are ocular surface deformation and early development of symblepharon, amniotic membrane is used as an adjunctive treatment.

To conclude this case report sensitizes the dermatologists regarding adverse effects of the commonly used topical agent KMnO4 and enhances the awareness of this condition for prompt management.

Source- Kandpal R, Gautam S. Accidental ocular injury by topical dermatological agent: Potassium permanganate (KMnO4). Indian Dermatol Online J 2021;12:752-4.