Neuromyelitis Optica and the Optic Neuritis Treatment Trial—Reply

In reply

My coauthors and I thank Dr Gotkine for his relevant comments regarding the long-term results of the ONTT. We agree that these findings will better assist clinicians in providing additional prognostic information for those presenting with an initial episode of optic neuritis.

The ONTT, which has captured more than 15 years of follow-up data on patients presenting with acute optic neuritis, occurred during a time when the serologic test for the NMO-IgG antibody was not available. The trial did not capture subsequent evaluations with spinal cord imaging, so we did not have good tools to track which patients might have had or developed either serological or imaging evidence of potential NMO.

During the course of follow-up on this cohort of patients, 18 deaths were observed, 7 of which were considered related to multiple sclerosis and 1 to Devic disease (a patient who also had a diagnosis of Lyme disease) and where the death was inconclusively related to multiple sclerosis. Not surprisingly, the patient with Devic disease had normal MRI results at study entry and died from a cardiopulmonary event 11 years following the initial visual loss. The specifics of the Devic disease diagnosis in this patient, however, are not known.

We agree that any clinical trial looking at acute optic neuritis as a clinically isolated syndrome would be well served by consideration of obtaining serum for NMO-IgG antibody titer testing, particularly if the optic neuritis is bilateral, painless, and unremitting or if the patient has a history of systemic autoimmune disease. Recent articles support the fact that early testing may have clear implications for long-term management, particularly in those with recurrent optic neuritis.^{1 - 2}

Correspondence: Dr Smith, Genentech, Inc, 1 DNA Way, South San Francisco, CA 94080-4990 (smith.craig@gene.com).

Financial Disclosure: Dr Smith is a full-time employee of Genentech, Inc.