Immunostaining of skin biopsy adds no diagnostic value in MGUS-associated XXXX .

@entity1 @entity1581 @entity16 @entity1897 @entity8057
BACKGROUND AND PURPOSE: For several decades an association between MGUS, IgM-MGUS in particular, and @entity1897 has been suspected. Several histopathology studies have shown binding of IgM to myelin and a secondary widening of myelin lamellae in cutaneous nerves and in the sural nerve of @entity1 with IgM-MGUS, or Waldenstr  m's @entity8057 (WM), and @entity1897 . In this retrospective study we investigated the value of skin biopsy examination in the diagnosis of MGUS- and WM-associated @entity1897 . METHODS: A total of 117 @entity1 , who were examined for an M-component in serum with associated nerve symptoms, had a skin biopsy taken and examined for immunoglobulin deposition in cutaneous nerves. Thirty-five @entity1 were diagnosed with MGUS or WM and @entity1897 with no other cause of @entity16 . Nineteen @entity1 had MGUS but no @entity1897 . RESULTS: Of the 35 @entity1 with MGUS or WM and @entity1897 , four had immunoglobulin deposition in the skin biopsy, all of whom had an @entity1581 . In the control group of 19 without @entity1897 , three had immunoglobulin deposition in the skin biopsy, all of whom had IgM-MGUS. In both groups, there was a trend towards higher IgM blood levels in @entity1 with immunoglobulin deposition. Half of the @entity1 with @entity1581 in the @entity16 group had anti-MAG reactivity, whereas only one in the control group had weak anti-MAG reactivity. CONCLUSION: Our study indicates that examination of skin biopsies for immunoglobulin deposition does not add significant diagnostic value in the evaluation of @entity16 suspected to be caused by MGUS or WM. IgM immunoglobulin deposition in skin biopsy might merely be an epiphenomenon secondary to high IgM blood levels.
