Midface Toddler Excoriation Syndrome (MiTES): a new mimic of non-accidental injury

Abstract Background Midface Toddler Excoriation Syndrome (MiTES) is a rare genetic condition first described in 2017. Commencing in the first year of life, it is characterised by intense mid-­facial itch with persistent scratching and skin breakdown. Symptoms improve later in childhood, leaving atrophic scarring. Disbelief that infants can damage themselves in this way can lead to an erroneous and damaging misdiagnosis of non-accidental injury (NAI). Cases A boy now aged 11 years presented at 6 months with recurrent scratching of the face, leading to ulceration of the nasal bridge, sides of the nose, infraorbital areas and central forehead. Extensive investigations were unhelpful and NAI was suspected with significant psychosocial sequelae for the family. When his sister, now aged 4 years, presented with strikingly similar lesions MiTES was suspected and confirmed by genetic testing which showed homozygosity for 18 alanine repeats in the PRDM12 gene. Testing of sibling and parents is planned. Both children are now asymptomatic but have significant facial scarring. Discussion Biallelic variants in PRDM12 usually cause hereditary sensory and motor neuropathy type 8 with widespread damage to distal appendages due to pain insensitivity. The specific variant found here and in all reported MiTES cases causes highly localised lesions with rarely any extra-facial ­involvement. Due to its novelty and rarity, MiTES may be misdiagnosed and safeguarding concerns raised, leading to distress for affected families and breakdown of parent-­provider relationships. This case, which for the first time provides longitudinal data on affected siblings, highlights the need for early recognition and diagnosis.