An autoimmune screen was ordered including aquaporin-4 antibody (AQP4), myelin oligodendrocyte glycoprotein (MOG) antibody testing, anti-neutrophil cytoplasmic antibodies (ANCA), antinuclear antibody (ANA), double-stranded deoxyribonucleic acid antibody (DSDNA), anti-Sjogren’s Syndrome-related Antigen A antibody (SSA) and Anti-Sjogren’s Syndrome-related Antigen B antibody (SSAB), all of which were normal. A fluorodeoxyglucose positron emission tomography (FDG-PET) scan was requested, but due to limited resources, took several days before it was performed at another hospital. This evidence concerns the gene AQP4 and Down syndrome.