A Rare Case of Susac’s Syndrome Masquerading as Progressive-Relapsing Multiple Sclerosis – Cureus
Susac’s syndrome (SS) is a rare, autoimmune-mediated vasculitis involving central nervous system (CNS) microvasculature, which typically targets the brain, retina, and cochlea. The disease pathology in these regions produces the characteristic triad of encephalopathy, visual loss, and hearing loss. Unfortunately, less than 20% of cases present as the full triad, often making diagnosis challenging. Diagnosis is also confounded by the similarity in the clinical presentation of multiple scler…….
Susac’s syndrome (SS) is a rare, autoimmune-mediated vasculitis involving central nervous system (CNS) microvasculature, which typically targets the brain, retina, and cochlea. The disease pathology in these regions produces the characteristic triad of encephalopathy, visual loss, and hearing loss. Unfortunately, less than 20% of cases present as the full triad, often making diagnosis challenging. Diagnosis is also confounded by the similarity in the clinical presentation of multiple sclerosis (MS), with an overlap also seen in laboratory studies and radiographic imaging. In this report, we present a case of SS in a young and previously healthy adult male that was initially mistaken as MS. We review the characteristics of SS and highlight the key differences between the two diseases that can be used by diagnosing physicians. Lastly, we describe the treatment strategies involved in SS compared to MS.
Introduction
Susac’s syndrome (SS) is a rare, autoimmune-mediated vasculitis involving central nervous system (CNS) microvasculature [1]. This disease typically targets the brain, retina, and cochlea, giving the characteristic triad of encephalopathy, vision loss, and hearing loss. Less than 20% of cases present as the full triad, often making diagnosis challenging. The purpose of this case report is to discuss the difficulty in diagnosis of SS and highlight the key clinical differences between the presentation and diagnostic studies of SS and multiple sclerosis (MS) that can be used by diagnosing physicians. As the treatment of SS and MS can be starkly different, misdiagnosis and subsequent treatment failure can lead to irreversible neurological damage to the patient. As this disorder has an “orphan disease” status, adding our patient’s clinical course to the known SS literature is vital. This case describes a 21-year-old male who presents with neurological complaints that are originally misdiagnosed as MS before SS is correctly diagnosed.
Case Presentation
A previously healthy 21-year-old male presented to the emergency department (ED) with complaints of slurred speech, blurry vision, left-sided weakness, and progressive memory loss. He first noticed these symptoms four weeks prior to presentation and described them as intermittent in nature and without any obvious triggers or associations. The duration of the symptoms was variable, lasting anywhere from several days to weeks with large periods in between when the patient was symptom-free. At times, the visual dysfunction and vertigo became so severe that they resulted in multiple falls. Vital signs were normal as was the physical exam aside from the neurological portion, which revealed an ataxic gait, recall memory of 2/3 objects, anomic aphasia, and dysdiadochokinesia with poor finger to nose testing that was worse on the left side. All findings were highly unusual for his age and unremarkable medical history.
The initial workup consisted of a noncontrast CT scan of the head, complete blood count (CBC), comprehensive metabolic panel (…….
