Ocular Toxicity due to Accidental Exposure to Plant Latex by Calotropis procera and Calotropis gigantea

Abstract

Introduction: Calotropis is a member of the milkweed or Asclepiadeae family. The latex of Calotropis gigantea (C gigantea) contains cardiac glycosides, fatty acids and calcium oxalate. The sap of Calotropis procera (C procera) produces acidic latex. Toxic effect of latex manifests after a few hours with diminution of vision due to corneal oedema with folds in Descemet’s membrane. Aim: To evaluate the ocular toxicity by the latex of calotropis procera and calotropis gigantea due to accidental exposure. Materials and Methods: This was a prospective observational study conducted for a duration of six months (September 2018 to February 2019) on 18 patients with alleged accidental exposure to calotropis latex. The patients were examined in the Department of Ophthalmology, Mandya Institute of Medical Sciences (MIMS), Mandya, Karnataka, India. After a thorough saline wash under topical anaesthesia, visual acuity was measured by using Snellen’s chart, then patients were subjected for slit lamp biomicroscopy examination, Intraocular Pressure (IOP) measurement and undilated fundus examination and the findings were noted. Demographic details like age and sex, activity at time of injury, mode of injury were noted and follow-up was done for a period of 30 days. Data were analysed using Epi info software and descriptive statistics like mean and percentage were calculated. Results: Total 18 patients reported with calotropis associated eye toxicity, among which 11 (61.1%) were of C gigantea and seven (38.9%) were of C procera. Out of total, seven (38.9%) were males and 11 (61.1%) females. A total of 14 (77.8%) patients presented within 24 hours of injury. Eleven (61.1%) patients had involvement of both the eyes. The main symptoms were burning, irritation, foreign body sensation and diminution of vision. Best Corrected Visual Acuity (BCVA) varied from 6/9 to 6/60. Corneal oedema or striate keratopathy was the most common sign. Corneal oedema resolved in one week in case of C procera with use of topical corticosteroids except in three cases of C gigantea which took two weeks. Conclusion: C procera and C gigantea causes significant corneal oedema and ocular morbidity. By simple health education and occupational precaution, we can prevent ocular morbidity.

Keywords

• chemical injury
• corneal oedema
• striate keratopathy