Susac's syndrome - A new ocular finding and disease outcome

Susac syndrome in a patient with chronic myelocytic leukemia: Consequence or coincidence?

Purpose

In this study, we report a patient who presented with both chronic myelocytic leukemia (CML) and Susac syndrome (SS).

Observations

A 45-year-old male diagnosed with CML in the blast phase sought consultation due to a deterioration in vision in his right eye. He also had hearing loss and severe migraneous headaches. Best corrected visual acuity was light perception and 20/20 in the right and left eyes, respectively. The slit lamp examination and intraocular pressure were within normal ranges for both eyes. Upon dilated fundoscopy, organized vitreous hemorrhage was observed in the right eye, while the left eye exhibited extensive sclerotic vessels with retinal neovascularization in the periphery. Ultrasound of the right eye showed tractional retinal detachment. Optical coherence tomography of the left retina showed thinning of the retina in temporal macula. Fluorescein angiography revealed a substantial nonperfused region in the peripheral left retina, accompanied by arterioarterial and arteriovenous collaterals, along with microaneurysms. MRI showed scattered foci of hyperintensity within the supratentorial white matter, mostly subcortical on T2-weighted and fluid-attenuated inversion-recovery. The patient received a diagnosis of SS and was subsequently referred to the neurology service for further assessment and potential treatment.

Conclusion and importance

SS may manifest as a presentation of CML. It is advisable to conduct investigations for SS in CML patients experiencing neurological, ophthalmological, or otological symptoms.

Susac syndrome: neurological update (clinical features, long-term observational follow-up and management of sixteen patients)

Susac syndrome is a likely autoimmune microangiopathy affecting the brain, retina and inner ear. Due to the rarity of this condition, diagnosis and treatment can be challenging. Diagnosis is based on the presence of the clinical triad of central nervous system dysfunction, branch retinal artery occlusions and sensorineural hearing loss. Typical MRI findings of callosal and peri-callosal lesions may assist in diagnosis. Clinical course can be monophasic, polycyclic or chronic continuous. It is important to look out for red flags to attain an accurate diagnosis and follow a therapeutic algorithm based on severity of the disease and response to treatment. Patients are treated with steroids and immunosuppressive agents with a variable response. Early aggressive treatment especially in severe cases, may help in preventing relapses and morbidity/disability. This study highlights important diagnostic features and proposes a treatment algorithm based on clinical experience from management of 16 patients from 2 neuroscience centres in the UK since 2007, who were followed up over a long period of 3-15 years.