Diagnosing Susac Syndrome Despite Incomplete Clinical Triad: A Case Report of Convergent Atypical Neuroimaging and Inflammatory Cerebrospinal Fluid Findings: Case Report
This case report illustrates that Susac syndrome can be diagnosed and treated effectively in patients lacking the complete clinical triad or full EuSaC criteria by relying on characteristic neuroimaging findings, such as corpus callosum "snowball" lesions, and a specific inflammatory cerebrospinal fluid profile to prevent irreversible neurological damage.
Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer
The human body is a complex network of blood vessels that deliver oxygen and nutrients to every organ, including the brain, eyes, and ears. Sometimes, the immune system, which is designed to fight off infections, mistakenly attacks these tiny blood vessels. When this happens in a specific pattern affecting the brain, the retina of the eye, and the inner ear, it creates a rare condition known as Susac syndrome. This disorder causes inflammation that blocks blood flow, leading to a classic trio of symptoms: confusion or memory loss, vision problems, and hearing loss. However, the disease is notoriously difficult to catch because most people do not show all three symptoms at once. Doctors often struggle to distinguish it from more common conditions like multiple sclerosis, a disease that also causes inflammation in the brain and spinal cord but follows different rules. Getting the diagnosis right is critical because the treatments differ, and delaying care can lead to permanent damage to a person's mind, sight, and hearing.
A team of researchers at the University of Central Florida College of Medicine recently shared the story of a woman in her early forties who presented a significant diagnostic puzzle. She arrived at the hospital with worsening balance issues, dizziness, and weakness in her legs. Her medical history was complicated by high blood pressure, kidney disease, and a tendency to form blood clots, which had already caused her to have several strokes in the past. Because of this history, her initial symptoms looked very much like another stroke or perhaps a flare-up of multiple sclerosis. Standard tests, such as a CT scan of her head, showed old damage from previous strokes but did not immediately reveal the cause of her new problems.
The turning point came when the medical team performed a magnetic resonance imaging, or MRI, scan of her brain. This detailed picture revealed a specific pattern of damage that is highly characteristic of Susac syndrome. The scan showed small, round lesions in the center of the corpus callosum, the thick bundle of nerve fibers that connects the left and right sides of the brain. These lesions, described by doctors as having a "snowball" appearance, are a hallmark of the disease. Additionally, the scan showed inflammation along the surface of the cerebellum, the part of the brain that controls coordination. These imaging findings were distinct from what is typically seen in multiple sclerosis, which usually affects different parts of the brain and spinal cord.
To understand what was happening inside the patient's central nervous system, the doctors also analyzed a sample of her spinal fluid. The results showed signs of active inflammation and damage to the protective coating of nerve fibers, but they lacked a specific marker, known as oligoclonal bands, that is almost always present in patients with multiple sclerosis. This absence was a crucial clue. While the patient did not yet have confirmed evidence of the eye or ear damage required to officially diagnose Susac syndrome according to standard medical guidelines, the combination of the unique "snowball" brain lesions, the specific type of spinal fluid inflammation, and the suspicion of hearing loss strongly favored the rare condition and prompted the team to begin treatment.
Based on this convergence of evidence, the medical team decided to treat the patient for Susac syndrome immediately, rather than waiting for the full set of symptoms to appear. She received high doses of steroid medication to reduce the inflammation. While her physical examination did not show dramatic improvement right away, she reported feeling subjectively better, and the treatment avoided the risk of waiting too long and causing irreversible harm. The patient unfortunately could not continue with follow-up care due to a lack of insurance and social support, but her case provided a vital lesson for the medical community.
This report suggests that doctors should not wait for a patient to display every single symptom of Susac syndrome before starting treatment. When the brain scan shows the distinctive "snowball" lesions and the spinal fluid points away from multiple sclerosis, the diagnosis can be strongly suspected and treatment initiated even if the full picture is not yet complete. By recognizing these specific patterns early, physicians can intervene sooner, potentially saving patients from permanent disability. The case underscores that in medicine, sometimes the most important clues are found not in a checklist of symptoms, but in the unique signature left behind by the disease on the body's most delicate structures.
Drowning in papers in your field?
Get daily digests of the most novel papers matching your research keywords — with technical summaries, in your language.