Mid-face toddler excoriation syndrome (MiTES): A case series

Dear Editor,

Midface toddler excoriation syndrome (MiTES) is a rare condition characterised by self-inflicted scratching over the glabellar area, leading to severe scarring and disfigurement, which may be associated with a positive regulatory domain-containing protein 12 (PRDM12) gene mutation.¹ We present a case series of six patients from four families.

All patients with classical excoriation, deep ulceration, self-inflicted injuries, or scars at the centrofacial glabellar region, extending up to supra and infraorbital regions, were analysed in the current series [Figure 1 and Supplementary Figure 1]. Details on clinicodemographic data, consanguinity, family history, and progression of symptoms have been tabulated in Table 1.We performed temperature, fine touch sensory tests, deep tendon reflexes, and starch iodine test to evaluate autonomic nerve function. Whole-exome sequencing (WES), trichoscopy, and onychoscopy were performed in all cases. The mean±standard deviation [M±SD] age of onset of disease was 15±3 months, ranging from 6 to 36 months, with no sex predilection. Among these six patients, four had a family history and were born to a consanguineous healthy couple. Apart from decreased pain sensation over the mid-face and extremities (33.3%), we found trichoteiromania (due to rubbing) in three patients and onychotillomania in three patients. Notably, we observed a distinct pattern where patients with trichoteiromania did not concurrently exhibit onychotillomania. Other associated features include palmoplantar hyperhidrosis and oral biting in one patient each. Trichoscopy (of three patients) revealed upright regrowing hair in one (33.3%), broken hair in two (66.6%), broom hair in one (33.3%), and variable length of hair in two (66.6%) [Figure 2a]. Onychoscopy (of three patients) demonstrated hang nails in all three, pinpoint haemorrhages and distorted cuticles in two patients each [Figure 2b]. The rest of the systemic examination and routine investigations were normal in all patients. WES revealed PRDM12 and heterozygous variation in Exon 30 of the SCN11A gene in the form of a single base substitution at codon 1560 (p.Met1560Val) in three and two patients, respectively. WES could not be performed in one patient due to monetary issues. We recommended a combination of pharmacological and behavioural interventions. Moisturisers and mild topical corticosteroids were prescribed to reduce inflammation and pruritus. Caregiver education emphasising the importance of distraction techniques and maintaining a calm environment to prevent exacerbation of symptoms was considered.

Close

Figure 1:

Lichenified and healed excoriated hyperpigmented plaque over theglabella, dorsum of nose, supra, and infraorbital region.

Export to PPT

Close

Figure 2a:

Trichoscopy demonstrates broom hair and broken hair. (polarised, 100x, contact, videodermoscope).

Export to PPT

Close

Figure 2b:

Onychoscopy depicts hang nail, hemorrhages and ragged cuticle (Dermlite DL4, 10x, polarised mode).

Export to PPT

MiTES is diagnosed clinically in toddlers (aged 1-4 years) based on recurrent, symmetrical excoriations (scratches, erosions, or scabs) localised to the mid-face, primarily the cheeks, nasal bridge, and periorbital areas, without an underlying primary rash. Unlike pruritic conditions like eczema or scabies, itching is typically mild or absent, and scratching may occur unconsciously (e.g., during sleep or as a habitual response to dryness or irritation), in the absence of vesicles, pustules, or burrows, along with exclusion of mimics such as atopic dermatitis, impetigo, herpes simplex, or contact dermatitis. The condition is often linked to environmental factors (e.g., dry skin, cold exposure) or behavioural triggers (e.g., self-soothing habits).

MiTES should be differentiated from other causes of self-inflicted skin damage, such as hereditary sensory and autonomic neuropathies (HSAN) type VIII, congenital insensitivity to pain (CIP) with anhidrosis, familial dysautonomia, trigeminal trophic syndrome (TTS), dermatitis artefacta, and neurotic excoriations. It can be clinically separated from its differentials in terms of early onset of symptoms with characteristic midface localisation and lack of generalised insensitivity to pain. MiTES is a newly described pain disorder with heterogenous genetic mechanisms, including an autosomal recessive type caused by biallelic PRDM12 polyalanine tract expansion and an autosomal dominant type caused by SCN11A.² Few consider it a localised variant of HSAN type VIII, wherein a biallelic mutation in the PRDM12 gene is seen, with the afflicted individual often suffering from ulceration of the distal digits, facial scratching, corneal ulcers, along with ulceration of the lips and tongue. Light touch, vibration, and proprioception sensations carried via the large sensory fibres remain unaffected, but patients with HSAN type VIII can experience reduced sweating and tearing with autonomic dysfunction.³ Acral involvement may be seen in MiTES, though less frequently. However, in our case series, the features of nail biting were visible. A possibility could be that MiTES may represent an early manifestation of HSAN, and affected children may develop more typical features of HSAN, such as oral, corneal, or severe acral mutilating lesions on longer follow-up. Further, habitual scratching maybe observed in up to 18.5% of affected children⁴, sometimes manifesting as trichoteiromania, particularly involving the eyebrows and presenting clinically as madarosis. In our case series, three patients with a PRDM12 mutation demonstrated features of trichoteiromania.

MiTES is differentiated from TTS by segmental involvement in the latter. However, atypical TTS can have bilateral involvement, but nasal ala destruction and nasal tip involvement are classically seen in TTS.⁵ MiTES is delineated by neurotic excoriation and periocular dermatitis artefacta by a characteristic “X pattern” (glabella with wing-like extension to supra and infra orbital region bilaterally) and insensitivity to pain.⁶

MiTES might indicate a restricted or initial expression of HSAN, yet its presentation remains consistent and distinctive. As more cases are observed, a correlation between genotype and phenotype may become evident, making documentation even more imperative. We also emphasise that apart from the PRDM12 mutation, we found a novel mutation of the SCN11 gene (in two patients), which has been reported in only one case to date.