[Two siblings with congenital adrenocortical unresponsiveness to ACTH showing peripheral neuropathy--morphometric evaluation of the sural nerve].

A 13-year-old boy, with the diagnosis of congenital adrenocortical unresponsiveness to ACTH (ACTH insensitivity) at age 7, developed a steppage gait, when under glucocorticoid replacement therapy at age 13. The parents were healthy and not consanguinous. On general physical examination, a mild diffuse skin hyperpigmentation was noted. Neurological examinations revealed that all the muscle stretch reflexes of both limbs were absent without pathologic reflexes. Pes cavus was found bilaterally. A slight decrease of tactile sensation was noted distal to the ankle joints. Pain sensation was slightly decreased in the toes. On laboratory examination, the conduction velocities of the left ulnar and median motor nerves were 51 and 45 m/sec, respectively, which are normal. No M-wave responses were obtained by electrical stimulation of the tibial and peroneal nerves. The coefficient of the variation of the R-R interval from ECG recordings was normal. Orthostatic hypotension was not observed. Achalasia was negative on the barium swallow esophagram. Therefore, it was concluded that he had motor and sensory polyneuropathy, and a right sural nerve biopsy was performed. A 12-year-old girl, a sister of the boy described above, with the diagnosis of ACTH insensitivity at age 5, noted a pain on the medial aspect of the left sole after skating. On general physical examination, a mild diffuse skin hyperpigmentation was discovered. On neurological examination, a spontaneous pain with dysesthesia was noted on the plantar aspect of the 1st, 2nd and 3rd left toes and on the anterior and medial aspect of the sole. Otherwise she was normal. A diagnosis of the left tarsal tunnel syndrome was made.(ABSTRACT TRUNCATED AT 250 WORDS)