Degos disease mimicking primary vasculitis of the CNS

A 4-year-old boy developed a headache. Initial evaluation revealed a normal neurologic examination and a right subdural hygroma on CT. Worsening headaches led to hospitalization at an outside institution. MRI showed leptomeningeal enhancement; magnetic resonance angiography (MRA) was normal. Infectious, rheumatologic, hematologic, and CSF studies were unrevealing. He then developed a left-sided hemiparesis. Imaging showed increased leptomeningeal enhancement with punctate infarcts in the right hemisphere. CT angiography demonstrated irregularity involving branches of the circle of Willis suggestive of vasculitis. Methylprednisolone (30 mg$kg$d 3 5 days) was administered for presumed CNS vasculitis. Despite continued glucocorticoid therapy, the patient developed increasing left-sided weakness. Repeat imaging showed perivascular inflammation. Headaches continued and examination revealed leftsided hemiparesis, new-onset right leg weakness, bilateral clonus, and extensor plantar responses. IV cyclophosphamide (dosed every 2 weeks for 4 doses; titrated to 1,000 mg/m) was initiated for presumed CNS vasculitis. Rituximab (750 mg/m 3 2 doses) and IV immunoglobulin (2 g/kg divided over 4 days) were added for worsening MRI findings. However, he developed new multifocal infarcts. Infliximab (5 mg/kg) was initiated based on use in resistant CNS vasculitis. Two months after initial diagnosis, the patient was transferred to our institution for a second opinion. Upon transfer, examination revealed weakness of the left face, arm, and leg; continued right leg weakness; a left homonymous hemianopsia; and bilateral clonus and extensor plantar responses. Spinal and brain MRI revealed multiple spinal cord lesions and acute infarcts in the anterolateral right pons. The patient developed right cranial nerve III palsy. He developed abdominal pain (attributed to neurogenic bladder and constipation). Abdominal and pelvic MRA and serologies did not demonstrate systemic vasculitis. Based on his subdural fluid collections, abdominal pain, and the refractory nature of his vascular process, Degos disease was proposed as a unifying diagnosis. Previously rash-free, the patient was now noted to have a 4-mm porcelain white abdominal papule with central atrophy and an erythematous rim (figure, C). A papule with a dull pink-gray center and red telangiectatic rim was present on his right foot (figure, D). Skin biopsy revealed central epidermal atrophy with hyperkeratosis and increased dermal mucin and fibrin thrombi (figure, F). Small dermal vessels demonstrated degeneration of their walls, leading to a smudged appearance (figure, F). Eculizumab and treprostinil were initiated for presumed Degos. The patient developed worsening abdominal pain. He was found to have 3 gastric perforations, which were repaired. He developed right upper extremity myoclonic movements necessitating intubation for sedation. MRI demonstrated worsened right-sided and new left hemispheric leptomeningeal enhancement, as well as a new subacute right thalamic infarct extending to the brainstem (figure, B). Anti-VLA4 therapy (natalizumab; 5 mg/kg) was added to reduce CD4 T-cell access into the CNS. MRI 1 week later revealed increasing bilateral hemispheric disease and progression of the deep gray nuclei and brainstem lesions. Palliative care was provided; the patient died of respiratory failure after elective extubation.