The use of nerve growth factor in herpetic keratitis : a case report

Background: We evaluate the role of nerve growth factor (NGF) eye drops to treat a herpetic corneal ulcer resistant to systemic and local acyclovir treatment in an HIV-positive patient. Case Presentation: A 68 year old HIV-positive male presented with a herpetic corneal ulcer which was treated unsuccessfully with acyclovir. Acyclovir sensitivity of herpes simplex virus was tested with a dye uptake assay and we found that the herpes simplex virus isolated was resistant to acyclovir. We started eye drop therapy with NGF and the corneal herpetic ulcer healed in 23 treatment days. Conclusion: The case presented here is the first described in the literature in which a herpetic corneal ulcer was successfully treated with NGF. We recommend that trials of NGF therapy in herpetic keratitis should be carried out on a larger number of acyclovir resistant cases. Background Herpes simplex virus (HSV-1) infections of the eye, and in particular keratitis, are quite frequent in people with acquired immunodeficiency syndrome [1] and are generally treated with acyclovir. Recently, there has been a progressive increase in the number of cases resistant to acyclovir [2] due to the development of viral strains resistant to the drug and the appearance of a gene tk mutation [3]. Experimental studies have recently demonstrated that nerve growth factor (NGF) is able to block HSV-1 reactivation [4] and is also able to repair neurotrophic corneal ulcers [5]. On the basis of this, we decided to use NGF eye drops to treat a corneal herpetic ulcer in an HIV-positive patient, where the herpes simplex virus was resistant to systemic and local acyclovir treatment. Case presentation A male patient, aged 68 years, was referred to us in October 2004 with a corneal herpetic ulcer in his right eye. The ulcer had appeared after an influenza vaccination. The anamnesis showed that the patient was HIV-positive without signs of AIDS and with a CD4 count of 496/mm3. Furthermore he was not on Highly Active Anti-Retroviral Treatment (HAART). We treated the patient with oral acyclovir, 800 mg five times daily, and topical acyclovir ointment four times daily. After 10 days of treatment no clinical improvement was observed (Fig. 1). We collected a sample of corneal cells that was found to be positive for HSV-1. The sensitivity of the isolated HSV-1 to acyclovir was tested using a dye uptake assay that measured the quantitative cytopathic effect [6] and we found that HSV1 isolates were resistant to acyclovir. On the basis of the persistence of the corneal herpetic ulcer we decided to discontinue the topical and systemic acyclovir therapies and to trial topical treatment with NGF eye drops. Before treatment the patient was informed of the procedures and the aim of the therapy and he signed Published: 31 October 2007 Journal of Medical Case Reports 2007, 1:124 doi:10.1186/1752-1947-1-124 Received: 4 August 2007 Accepted: 31 October 2007 This article is available from: http://www.jmedicalcasereports.com/content/1/1/124 © 2007 Mauro et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.