Background: One of the most frequent etiologies of endocrinal polyneuropathy is the hypothyroidism, that can cause axonal and demyelinating polyneuropathies.
Objective: To evaluate Subclinical affection of peripheral nerve among patient with subclinical hypothyroidism.
Patients and methods: Fifty consecutives recently diagnosed sub clinical hypothyroid patients referred from outpatients' clinic of Internal Medicine Department to Neurophysiology unit of Neurology Department of Al-Azhar University hospital in new Damietta, and fifty age and gender matched euthyroid healthy persons The electrophysiological study of all studied groups was done including motor and sensory nerve conduction studies of both median, ulnar, peroneal and sural nerves.
Results: As regard to motor conduction study. There was a significant deference between both groups as regard of CMAP amplitude of both peroneal nerves, conduction velocity of both median and both peroneal nerves. Regarding to sensory conduction study there was significant deference between both groups as regard of of sensory terminal latency, SNAP amplitude of both median and sural nerves. There was a significant negative correlation between TSH serum level and each of conduction velocity of both median, both peroneal, left ulnar nerves, compound motor unit action potential amplitude of both peroneal nerves, and sensory nerve action potential amplitude of right sural nerve. There was a significant +ve correlation between the TSH serum level and terminal latency of both peroneal and right sural nerves.
Conclusion: Subclinical hypothyroidism can be considered as risk factor of peripheral nerve affection as in cases of hypothyroidism