Reduced Myocardial Uptake of 123I-MIBG in Congenital Insensitivity to Pain With Anhidrosis

ABSTRACT A 30-year-old man presented with repeated episodes of painless injuries in his feet and abnormally high body temperature. He was diagnosed with congenital insensitivity to pain with anhidrosis-a rare hereditary peripheral neuropathy characterized by decreased pain, reduced sweating, and autonomic neuropathy. Congenital insensitivity to pain with anhidrosis is also called hereditary sensory and autonomic neuropathy type IV. 123I-MIBG myocardial scintigraphy showed reduced myocardial uptake (heart-to-mediastinum ratio: 1.56 and 1.42 in the early and late phases, respectively; washout ratio, 49%), indicating autonomic dysfunction. This finding may contribute to the diagnosis of congenital insensitivity to pain with anhidrosis and the semiquantitative evaluation of an autonomic dysfunction.