Diagnosis of HNPP Electrodiagnostic testing Genetic testing Hereditary motor neuropathy with liability to pressure palsies should be suspected in patients with any of the following: Recurrent compression mononeuropathies Multiple mononeuropathy of unknown origin Symptoms suggesting recurrent demyelinating polyneuropathy (eg, chronic inflammatory demyelinating polyneuropathy [CIDP]) A family history of carpal tunnel syndrome Electrodiagnostic testing and genetic testing aid in diagnosis; rarely, biopsy is required.