As far as the relevance of testing for inflammation markers is concerned, I've pasted below a copy a short excerpt taken from an article called "Complex regional pain syndrome in adults" by Andreas Goebel published in the Oxford University Journal of Rheumatology in 2010 (revised 2011). The relevant bit and the reason the blood work would have been requested by the pain specialist and any judgement reserved on whether it can be diagnosed as CRPS, is shown in red. Dr Goebel is one of the clinicians and researchers who could genuinely be called a CRPS specialist. The references in the text are to a copy of the Budapest Criteria which I didn't copy here but the full article is available free online if anyone wants to look at the criteria.


FIG. 2
Budapest diagnostic criteria (A–D must apply). Note that it is possible to distinguish between CRPS-1 (without damage to major nerves) and CRPS-2 [associated with (yet not causing) damage to a major nerve, a very rare presentation], but there is currently no RCT-derived evidence that this distinction has any consequence for treatment. aThe reflected understanding of allodynia as painful sensation to a number of normally non-painful stimuli is under review by the IASP taxonomy group. Some experts suggest that the term allodynia should be reserved only for brush-stroke evoked pain (dynamic mechanical allodynia). bHyperalgesia is exaggerated pain to a painful stimulus such as a pinprick. cFor example, raised systemic inflammatory markers are not associated with CRPS, even in the initial inflammatory phase; such a finding of raised markers would lead to a search for an alternative or concomitant cause. Abnormal nerve conduction studies do not exclude CRPS, but the primary cause of the observed abnormality must be clarified: CRPS, by definition is always secondary, its presence cannot explain major nerve damage. Figure adapted from Ref. [4].