201907-119212
2019
Fidelis Care New York
Medicaid
Infectious Disease
Infusion Therapy
Medical necessity
Upheld
Case Summary
Diagnosis: Viral Croup
Treatment: Gammagard
The insurer denied the Gammagard. The denial was upheld.
This patient is a young male with a history of autoimmune encephalitis. The patient had a prior viral infection presenting as croup. During that admission, he had mental status changes and weakness which was initially considered to be an encephalopathy or encephalitis. His mental status returned to normal by the time of discharge, but he developed pronounced behavioral and personality changes and had no neurologic deficits. His Magnetic Resonance Imaging (MRI) at that time could have suggested a demyelinating disorder. Over the ensuing months he continued to have episodes of mood changes, and emotional lability. Based on the patient records there is no clinical evidence of an organic disease process, inflammatory damage to the nervous system, or demyelination. Several months after discharge it was noticed that he was "positive" for anti-MOG antibodies (no titer is mentioned) and it was concluded that he had originally experienced, in retrospect, autoimmune encephalitis. The presence of anti-MOG does not confirm encephalitis. Detection of serum anti-MOG antibodies is associated with some patients with the demyelinating syndromes (acute disseminated encephalomyelitis (ADEM), multiphasic disseminated encephalomyelitis (MDEM), neuromyelitis optica spectrum disorders (NMOSD), and relapsing optic neuritis). Anti-MOG antibodies are not exclusively detected in patients with demyelinating syndromes, implying that anti-MOG antibodies can be present in other conditions.
The detection of anti-MOG antibodies in the patient could be coincidental, and most likely is not playing a causative role in his neuropsychiatric condition. Given this, intravenous immune globulin (IVIG) therapy would have no role in treatment of his syndrome, as the postulated mechanism of action of IVIG is anti-inflammatory, and there is no evidence the patient's condition is inflammatory, much less due to any antibody-mediated inflammation.
Based on the above, the medical necessity for Gammagard is not substantiated. The insurer's denial is upheld.