Neuro-immunology   

Specifically, do you check for any of these: ACE, Vitamin D 1,25, serum lysozyme, soluble IL2 or Adenosine deaminase levels?

For example, the patient may have other findings such as an elevated CRP. Would you diagnose SLE, or would you want to see other serologies or finding...

If not, are there any serum or CSF tests you consider to be helpful?

Is a biopsy or EMG helpful in confirming the etiology? What is the best treatment for sarcoid neuropathy?

Do you treat with only an IV steroid pulse or do you use an oral steroid taper as well? How long of a taper do you typically use?

In addition, what formula do you use to calculate the IgG index?

When it seems fairly certain that this is a drug effect is it something that can just be monitored or requires a change in approach?

Do you just use antibiotic prophylaxis if therapy is started prior to meningococcal vaccination?

Thoughts on sarilumab vs methotrexate, or just treat with steroids alone

Small study in pediatric PACNS have evaluated this as a potential marker (Cellucci et al., PMID 22740622)