Jacqueline Butler is a 27 year-old woman who presented at your primary care practice with tingling in her left hand that had been persistent for the past week. She has also been experiencing increasing clumsiness and weakness when using her left arm, as well as fatigue and trouble concentrating. A surface examination of her extremities showed no swelling, inflammation of joints, or noticeable cysts. Her body temperature was normal, as was a complete blood count (CBC) including a blood glucose test. Subsequently, you order a lumbar puncture to rule out infection and an MRI with contrast dye. The lumbar puncture shows elevated levels of IgG antibodies and the MRI showed three small inflammatory lesions within the brain. Based on these results, you diagnose Jacqueline with which disease?

Multiple sclerosis (MS) is the most common neurodegenerative and demyelinating inflammatory disease in adults between 18 and 35 years of age and is the second leading cause of neurological disability in young adults. This pathology is considered an organ-specific autoimmune disorder, characterized by multiple focal areas of demyelination called plaques or lesions, which are accompanied by different degrees of gliosis, inflammation and neuroaxonal damage. It usually manifests itself in coordination and balance problems, muscle weakness, difficulties in thinking and memorizing and sensations of numbness, as well as other symptoms. Diagnosis of MS is based on a clinical evaluation in which all symptoms, as well as the signs (overactive reflexes, incoordination, weakness of specific muscle groups, etc.) of the disease are documented. Magnetic resonance imaging (MRI) is used to obtain cross-sectional images of the brain and spinal cord, which can detect the small areas of inflammation and scarring in the brain typical of MS.Lumbar puncture is an analysis of a sample of cerebrospinal fluid (CSF), which has the function of cushioning the brain and spinal cord, to evaluate the abnormalities that occur in patients with MS. The most common CSF abnormality found in 80-90% of MS patients is an increase in the number of cells and proteins of the immune system (immunoglobulins), suggesting inflammation or a strong immune response. This test is particularly useful to diagnose patients who experience a slow and progressive decline in their functions without exacerbation pictures; that is, people with primary progressive multiple sclerosis, especially when no abnormalities are detected in the MRI images of the brain. CSF evaluation can also be used to exclude infections difficult to distinguish from multiple sclerosis.