Diagnostic Criteria

In March 2012 I lost ability to raise R arm, whole arm was really sore for about 6 weeks, EMG showed denervated serrateous anterior and I was diagnosed with Parsonage Turner syndrome. By May my feet/legs were occasionally feeling numb. By Aug I had experienced facial twitching and numbness and extreme pain in feet/ ankles with visible muscle wasting (indentations in feet and ankles). NC tests in legs have showed slow distal latencies, getting progressively worse (numbers are around 8)Legs feel very heavy and crapmy. Neuro says this isn’t yet enough to diagnose CIDP yet and to keep waiting. I’m scared of losing mobility since my arm still won’t raise at 7 months in. He says IVIG is too risky (he has had a patient have heart problem). What did it take for you to get diagnosed? How slow do my distal latencies have to get?

Consider a second opinion. If you have a spinal tap done and it shows elevated protein (may be up to 10 times normal), this will clinch the diagnosis 90% of the time, and you need treatment, If negative, you likely have another underlying cause.

EMG/NCS are specific patterns, but both the technique and interpretation of results can be open to operator/interpreting physician variances. The more I think about your situation, GET A SECOND OPINION!!

Spinal tap in June was negative. Now seeing neuro number 2 (not easy to do in Canada) Neither have been unable to diagnose my issue, both agree EMG shows increasing distal latencies (have had EMG done every 6 weeks)

Unless you are in the 10% of CIDP patients whom are negative for elevated CSF protein, you have low likelihood of CIDP (but not impoossible). However, your stated prolonged latencies are indeed consistent with a demyelinating process. One thing that can mimick this is diabetic neuropathy if you are diabetic.

The textbooks say that there is no magic number for distal latencies in order to make diagnoses. True demyelinization has been stated as greater than 10, but is not an exact science. You're clinical condition is more important.

It is possible taht you have multiple issues occurring. Make sure they have done appropriate labs, including, but not limited to Vit. D, thyroid function, heavy metal screening, B12, folate, ANA, Sed. rate, rheumatoid factor, tumor markers, CBC, metabolic profile, hemoglobin A1c, etc. There are actually a barrage of tests, which should be chosen based upon your clinical picture. A COMPREHENSIVE list can be found at the following link:

http://www.aafp.org/afp/2010/0401/p887.html