Diagnostic value of sural nerve biopsy in chronic inflammatory demyelinating polyneuropathy
- aDepartment of Neurology, bDepartment of Clinical Epidemiology and Biostatistics, Academic Medical Center, University of Amsterdam
- Dr DSM Molenaar, Department of Neurology (H2–214), Academic Medical Center, PO Box 22700, 1100 DE Amsterdam, The Netherlands. Telephone 0031 20 5663546; fax 0031 20 6971438; emailD.MOLENAAR{at}AMC.UVA.NL
- Received 19 May 1997
- Revised 22 July 1997
- Accepted 29 July 1997
Abstract
OBJECTIVE To investigate the additional diagnostic value of sural nerve biopsy of 64 patients in whom chronic inflammatory demyelinating polyneuropathy (CIDP) was considered, as sural nerve biopsy is recommended in the research criteria of an ad hoc subcommittee to diagnose CIDP.
METHODS Firstly, the additional diagnostic value of sural nerve biopsy was analysed with multivariate logistic re- gression. Six clinical features (remitting course, symmetric sensorimotor neuropathy in arms and legs, areflexia, raised CSF protein concentration, nerve conduction studies consistent with demyelination, and absence of comorbidity or relevant laboratory abnormalities) were entered into a logistic model. Afterwards, all significant features identified from this model, as well as the results of sural nerve biopsy were forced into a second logistic model. Secondly, the diagnostic performance of a neurologist experienced in diagnosis of peripheral nerve disorders was studied by receiver operating characteristics (ROC) curve analysis.
RESULTS The results of the first logistic analysis showed that CSF protein concentration >1 g/l (odds ratio (OR)=38.5) and neurophysiological studies consistent with demyelination (OR=51.7) were strong predictors of CIDP. When forcing the significant features and the sural nerve biopsy data into the model, an independent predictive value of sural nerve biopsy could not be found. The neurologist was able to discriminate patients with and without CIDP (area under the curve (AUC)=0.95). His diagnostic performance did not improve significantly by offering him the results of sural nerve biopsy.
CONCLUSION Any additional diagnostic value of sural nerve biopsy in the diagnosis of CIDP could not be shown.
