Clinical observation of toxic keratitis associated with vitamin A intoxication

Relevance Toxic keratitis is a rare but potentially dangerous condition that can lead to irreversible changes in the cornea and decreased vision. One of the poorly understood causes of its development is hypervitaminosis A, which occurs with excessive consumption of vitamin A. In clinical practice, such cases are rare, which makes their description important for understanding the pathogenesis, diagnosis and treatment of this condition [1, 2]. Objective Description of a clinical case of toxic keratitis that developed against the background of vitamin A intoxication, with the aim of raising physicians' awareness of this pathology and improving diagnostic and therapeutic approaches. Material and methods A clinical observation of a 34-year-old patient who was admitted with complaints of decreased visual acuity, photophobia and redness of the eyes is presented. The anamnesis revealed long-term intake of high doses of vitamin A as part of dietary supplements. Standard ophthalmologic examinations were performed: biomicroscopy, keratometry, optical coherence tomography (OCT) of the cornea, as well as laboratory tests to determine the level of vitamin A in the blood serum. Results Biomicroscopy revealed diffuse corneal opacities, areas of epithelial edema and neovascularization. OCT confirmed thinning of the corneal epithelium and the presence of subepithelial infiltrates. The level of vitamin A in the blood exceeded the reference values ​​by 2.5 times. Based on the clinical picture and examination data, the diagnosis was: toxic keratitis against the background of hypervitaminosis A. The patient was prescribed the withdrawal of vitamin A drugs, local anti-inflammatory therapy and keratoprotectors. After 4 weeks, positive dynamics were noted: a decrease in corneal opacities and an improvement in visual acuity. Conclusion Toxic keratitis due to hypervitaminosis A is a rare but clinically significant condition that requires timely diagnosis and treatment. Long-term use of high doses of vitamin A can lead to toxic damage to the cornea. Early discontinuation of the drug containing vitamin A and the administration of local anti-inflammatory therapy contribute to the regression of symptoms and restoration of vision [3, 4]. Keywords: keratitis; hypervitaminosis; corneal opacity; neovascularization; subepithelial infiltrates