CSS has been implicated as a key neuroimaging feature of CAA, a diagnosis which can be supported by the additional radiological findings of symmetrical white matter hyperintensities and enlarged perivascular spaces [
5]. For that reason, CAA was also included in the differential diagnosis of the patient, despite that no cognitive impairment was identified. However, TFNE which are defined as recurrent, stereotyped symptoms usually lasting for several minutes, have also been documented as part of the clinical manifestations of CAA [
6]. In addition, TFNE are shown to correlate well with the neuroimaging findings of CSS and disseminated CSS (in 4 or more sulci), which were present in our patient [
7]. TFNE with predominantly negative symptoms, such as our patient’s numbness, have been described as “TIA-like” episodes and are shown to be equally common to those with positive symptoms (“aura-like”) [
7]. The pathophysiological correlation between TFNE and CSS may lie in focal seizure activity or cortical spreading depression due to cortical irritation, but, additionally, local vasospasm due to accumulating blood-breakdown products may lead to predominantly negative symptoms [
8]. In the case of our patient, an epileptic origin of the symptoms may have been possible, despite the normal EEG. Symptomatic seizures could occur for a limited time when caused by an acute bleeding event and then stop after consolidation of the bleeding when antiplatelets were withdrawn. Conversely, the addition of antiplatelets in patients with CSS may escalate the frequency and severity of TFNE, while it increases exponentially the risk of intracerebral hemorrhage [
9]. It is important to differentiate between TFNE and TIAs by performing brain MRI with susceptibility-weighted imaging sequence.
In conclusion, the present case highlights that recognition of CSS is crucial in the management of patients presenting with transient focal neurological symptoms that can be misdiagnosed as recurrent TIAs, leading to initiation and escalation of antiplatelet treatment and possibly symptom worsening due to incident micro- and macro-bleeding.