Longitudinally extensive transverse myelitis with and without aquaporin 4 antibodies.

Abstract

IMPORTANCE:

Aquaporin 4 antibody (AQP4-Ab)-negative patients with longitudinally extensive transverse myelitis (LETM) behave differently from those with AQP4-Ab. Aquaporin 4 antibody-negative neuromyelitis optica (NMO) is rare when good assays are used.

OBJECTIVE:

To assess if AQP4-Ab-negative patients with LETM share similar disease characteristics with AQP4-Ab-positive patients or whether they have distinct features and alternative diagnoses. DESIGN We collated clinical and paraclinical data on patients with LETM identified through the Oxford NMO clinical database. Aquaporin 4 antibodies were tested using 2 sensitive assays. We describe the features of patients with LETM, compare findings between patients with and without AQP4-Ab, and describe alternative diagnoses in AQP4-Ab-negative patients.

SETTING:

Single specialist UK center for NMO.

PARTICIPANTS:

Seventy-six adult patients with LETM.

MAIN OUTCOMES AND MEASURES:

Comparison of clinical and paraclinical data.

RESULTS:

Fifty-eight percent of patients were AQP4-Ab positive. Alternative diagnoses could usually be identified in AQP4-Ab-negative patients, including those fulfilling NMO diagnostic criteria. Only 6.5% of patients had "true" seronegative NMO and 6.5% had idiopathic LETM. There were some important differences between AQP4-Ab-positive and -negative cases, including older onset age, higher proportion of females, lower incidence of simultaneous optic neuritis, lower frequency of conus involvement, and higher prevalence of coexisting autoimmune disorders in AQP4-Ab-positive cases. Attack severity and degree of recovery were similar in the 2 groups.

CONCLUSIONS AND RELEVANCE:

Patients with LETM without AQP4-Ab include a number of different diagnostic categories and it is not surprising therefore that they show important differences compared with AQP4-Ab-positive patients, even when considering only those fulfilling current NMO diagnostic criteria. Thus, we suggest that diagnoses such as myelin-oligodendrocyte glycoprotein antibody disease, multiple sclerosis, acute disseminated encephalomyelitis, and postinfectious disorders should be exclusions in the NMO diagnostic criteria and AQP4-Ab-positive and antibody-negative NMO/NMO spectrum disorder cohorts should be analyzed separately.

• Authors: Joanna Kitley, Maria Isabel Leite, Wilhelm Küker, Gerardine Quaghebeur, Jithin George, Patrick Waters, Mark Woodhall, Angela Vincent, Jacqueline Palace
• Journal: JAMA neurology (JAMA Neurol) Vol. 70 Issue 11 Pg. 1375-81 (Nov 2013) ISSN: 2168-6157 [Electronic] United States
• PMID: 23999580 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Aquaporin 4
• Autoantibodies

Topics

• Adult
• Aged
• Aquaporin 4 (immunology)
• Autoantibodies (blood)
• Female
• HEK293 Cells
• Humans
• Kaplan-Meier Estimate
• Longitudinal Studies
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Myelitis, Transverse (blood, complications, diagnosis, physiopathology)
• Neuromyelitis Optica (blood, complications, diagnosis)
• Retrospective Studies
• Statistics, Nonparametric
• Transfection