Case 1: A 57-year-old man presented with progressive myelopathy. Imaging revealed innumerable miliary enhancing nodules within the brain stem, spinal cord including the conus, leptomeningeal involvement, and nodular lesions within the lung parenchyma. CSF and serum testing were unrevealing for common causes. Clinical and radiographic improvement was achieved with pulse dose steroids followed by prolonged taper. Testing while not on any therapy, revealed hypogammaglobulinemia, lymphopenia, and impaired vaccine response. He was diagnosed with CVID and received IVIg for 3 months. After 1.5 years of clinical stability, he presented with left optic neuritis requiring prolonged prednisone taper. His symptoms worsened after tapering off prednisone, prompting re-initiation of an oral prednisone taper, initiation of mycophenolate mofetil, and re-initiation of IVIg.
Case 2: 70-year-old man with a history of granulomatous inflammation on lymph node biopsy 10 years prior presented with left eye ptosis and blurred vision. MRI of the orbits and lacrimal gland biopsy were consistent with orbital pseudotumor. He was started on prednisone and methotrexate with improvement in symptoms, followed by prolonged steroid taper down to 8mg daily. Testing revealed isolated lymphopenia and hypogammaglobulinemia, and poor vaccine response consistent with CVID. Retrospectively, lymphopenia was present for many years. He was transitioned from methotrexate to mycophenolate mofetil, with persistent lymphopenia and hypogammaglobulinemia not attributable to low dose prednisone or prior methotrexate therapy, prompting diagnosis of CVID with plan to initiate IVIg and discontinue steroids.