Sebina Bulic, MD

Khurram A, Kleinig T, and Leyden J. Clinical Associations and Causes of Convexity Subarachnoid Hemorrhage. Stroke. 2014

This very interesting study is coming from South Australia. The authors retrospectively reviewed electronic discharges for subarachnoid hemorrhage (SAH)-coded cases rom South Australian public hospitals between January 2005-July 2011 and extracted non-traumatic convexity SAH cases. Despite major difficulty in identifying etiology of SAH due to incomplete work up and retrospective nature of data analysis, this work managed to highlight incidence and etiology of this clinically very important entity.

cSAH represents 30-50% of non aneurysmal SAH or 6% of all SAH. As expected (beware that this number is just going to increase as population gets older), leading cause of cSAH is cerebral amyloid antipathy (CAA) with 39%. This number could potentially be higher because patients that were sub-optimally investigated (20%) were mostly over 65 year old, population at risk for CAA. Clinical presentation and patient age for CAA was very different from  the second cause of cSAH;RCVS that occurred in 17% cases, mostly in patients less than 60. Followed cerebral venous sinus thrombosis (CVST) 10%, severe vascular stenosis, 10% PRES 5% and cryptogenic 19% (this was under-investigated group).
Clinical presentation of cSAH for CAA occurred mostly in patients older than 65, symptoms were milder, commonly mistaken for TIA, and was mismanaged with antiplatelets, I take it as “warning for IPH”, but that is a whole another story.
This work raises awareness of this clinically very important entity. One has to look for it, because it can easily be overlooked and consequences can be significant.
My take on cSAH is; in the case of CAA if symptoms are milder, gives me a golden opportunity for aggressive risk factor modification for IPH prevention. In the case of more severe symptoms, as well as in management of other entities, my patient would need close monitoring and aggressive medical management. In either case, I cannot afford to miss it.