Mutilating hereditary sensory and autonomic neuropathy associated with WNK1 gene

Case presentation: A 17-year-old girl presented recurrent skin injuries on both feet with onset at 2 years old. She had labile skin temperature with unexplained hyperthermia episodes. Parents were consanguineous and had two healthy younger brothers. Past medical history included chronic osteomyelitis of the right foot after recurrent skin cellulitis. On examination, there are acral mutilations on both hands and feet and dry skin; reduced bilateral and symmetrical length-dependent pain, touch and vibratory sensation to knees and elbows, absent on hands and feet. Deep tendon reflexes are globally absent, except triceps and pronator teres. Orthostatic hypotension and urinary or fecal incontinence are absent. Nerve conduction studies revealed absent sensory nerve action potentials on four limbs, with normal compound muscle action potentials. Hereditary sensory and autonomic neuropathies were suspected and a genetic panel confirmed a homozygous pathogenic variant c.3226C>T (p.Arg1076*) in WNK1 gene associated with autosomal recessive hereditary autonomic and sensory neuropathy type 2A (HSAN2A), but also a single pathogenic variant in DST gene, c.4152del (p.Glu1384Aspfs*2), associated with HSAN6.