Dear Editor,
We thank the author for taking interest in our article and raising vital issues.[1] The two publications of the Indian Neuro-Ophthalmology Research Group (INOSRG) regarding ethambutol toxicity aim at increasing awareness among physicians and ophthalmologists.[2,3]
The current document provides guidelines about the screening, diagnosis, follow-up, and treatment of ethambutol toxicity.[2] We agree that diagnosis of the toxicity is mainly clinical and does not require OCT, which when available may be useful to pick up early damage due to the toxicity. It is essential that all the peripheral centers should at least be equipped with basic tools: a visual acuity chart and Ishihara booklet.
INOSRG noted that most of the patients are not aware of the side effects of ethambutol and not many physicians find it pertinent to send patients for baseline examination before starting the medication. The author may refer to our publication that provides the measures to increase awareness and screening means that can be used at various levels.[3] Its recommendations include the following:[3]
Identification and baseline ophthalmic examination of high-risk patients.
Sensitize community health workers (CHWs), such as ASHA, who are involved in the TB program, about the side effects.
Inquire the patient about any visual complaints such as a decrease in vision or color perception on follow-up.
Physicians, if feasible, can have a visual acuity chart at their clinic where screening is possible.
Physicians and CHWs should make patients aware of the visual side effects of ethambutol so that they can seek help at the earliest.
With the inclusion of ethambutol as a part of the continuation phase in the Revised National Tuberculosis Control Program, 2016, it becomes essential for ophthalmologists to increase vigilance and sensitize physicians about this preventable drug-induced vision loss that adds to the misery of the patient.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
Acknowledgements
We wish to acknowledge the support of Cipla Ltd. in the conduct of the virtual meeting and the support in the drafting of the document.
References
- 1. Panigrahi PK. Comment on: Ethambutol toxicity: Expert panel consensus for the primary prevention, diagnosis, and management of ethambutol-induced optic neuropathy. Indian J Ophthalmol. 2022;70:1069–70. doi: 10.4103/ijo.IJO_2997_21. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2. Saxena R, Singh D, Phuljhele S, Kalaiselvan V, Karna S, Gandhi R, et al. Ethambutol toxicity: Expert panel consensus for the primary prevention, diagnosis and management of ethambutol-induced optic neuropathy. Indian J Ophthalmol. 2021;69:3734–9. doi: 10.4103/ijo.IJO_3746_20. [DOI] [PMC free article] [PubMed] [Google Scholar]
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