Acute neurological deficits, otherwise known as relapses, characterise relapsing-remitting forms of MS.  A high annualised relapse rate is associated with disability development in the future, and current therapeutic endeavours are aimed at reducing such relapses.  Clinically, relapses are typically represented by sensorimotor deficits, gait unsteadiness, optic neuritis etc.  While cognitive decline and worsening fatigue may accompany relapses, these are not regarded as relapses. 

In an upcoming issue of JNNP (read as “on-line” publication) Pardini and colleagues report on isolated cognitive relapses in MS, and link these with development of disability.  Importantly, the traditional sensorimotor symptoms were absent. An isolated cognitive relapse was defined as

(1) a transient significant cognitive decline in objective neuropsychological performance, as measured by a battery of tests (see manuscript)

(2) without clinical or subjective evidence of other new neurological signs and symptoms

(3) associated with brain disease activity defined as a positive gadolinium enhancing scan (although this was a non-essential criteria).

Read more at http://jnnp.bmj.com/content/early/2014/03/31/jnnp-2013-307275.full

J Neurol Neurosurg Psychiatry doi:10.1136/jnnp-2013-307275

Isolated cognitive relapses in multiple sclerosis

1. Matteo Pardini1,2,3,
2. Antonio Uccelli1,
3. Jordan Grafman4,
4. Özgür Yaldizli3,5,
5. Gianluigi Mancardi1,2,
6. Luca Roccatagliata2,6,7