TY - JOUR
T1 - Axonal attenuation and secondary segmental demyelination in myeloma neuropathies
AU - Ohi, Takakazu
AU - Kyle, Robert A.
AU - Dyck, Peter James
PY - 1985/3
Y1 - 1985/3
N2 - The sural nerves of 5 patients with osteosclerotic myeloma and polyneuropathy, of 3 patients with multiple myeloma and polyneuropathy, and of 6 healthy subjects were studied by neuropathological, morphomemmtric, and teased‐fiber approaches to assess cellular (Schwann cell or axon) vulnerability and to explore the mechanism of segmental demyelination. As compared with controls, the nerves of both types of myeloma neuropathy demonstrated a statistically significant and marked loss of myelinated fibers and increased frequencies of axonal degeneration among teased fibers at statistically significant levels. The peaks of diameter histograms of myelinated fibers of osteosclerotic myeloma/polyneuropathy nerves were displaced to smaller diameter categories, suggesting fiber atrophy. Segmental demyelination and remyelination was clustered, as found in secondary demyelination. Large‐and intermediate‐diameter myelinated fibers of osteosclerotic myeloma/polyneuropathyl nerves had significantly smaller axon calibers relative to myelin spiral length seen in electron micrographs. The loss of myelinated fiber axons, the shift of the peaks of diameter histograms to smaller sizes, the lack of noticeable increased numbers of demyelinated axons, the clustered distribution of segmental demyelination, and the axonal attenuation suggest a special axonal or neuronal vulnerabilityl and appear to provide an explanation for the observed segmental demyelination. Whether axonal attenuation has a perikaryaeal or proximal genesis now needs to be determined.
AB - The sural nerves of 5 patients with osteosclerotic myeloma and polyneuropathy, of 3 patients with multiple myeloma and polyneuropathy, and of 6 healthy subjects were studied by neuropathological, morphomemmtric, and teased‐fiber approaches to assess cellular (Schwann cell or axon) vulnerability and to explore the mechanism of segmental demyelination. As compared with controls, the nerves of both types of myeloma neuropathy demonstrated a statistically significant and marked loss of myelinated fibers and increased frequencies of axonal degeneration among teased fibers at statistically significant levels. The peaks of diameter histograms of myelinated fibers of osteosclerotic myeloma/polyneuropathy nerves were displaced to smaller diameter categories, suggesting fiber atrophy. Segmental demyelination and remyelination was clustered, as found in secondary demyelination. Large‐and intermediate‐diameter myelinated fibers of osteosclerotic myeloma/polyneuropathyl nerves had significantly smaller axon calibers relative to myelin spiral length seen in electron micrographs. The loss of myelinated fiber axons, the shift of the peaks of diameter histograms to smaller sizes, the lack of noticeable increased numbers of demyelinated axons, the clustered distribution of segmental demyelination, and the axonal attenuation suggest a special axonal or neuronal vulnerabilityl and appear to provide an explanation for the observed segmental demyelination. Whether axonal attenuation has a perikaryaeal or proximal genesis now needs to be determined.
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U2 - 10.1002/ana.410170306
DO - 10.1002/ana.410170306
M3 - Article
C2 - 2986526
AN - SCOPUS:0021965625
SN - 0364-5134
VL - 17
SP - 255
EP - 261
JO - Annals of neurology
JF - Annals of neurology
IS - 3
ER -