DermNet provides Google Translate, a free machine translation service. Note that this may not provide an exact translation in all languages

Epidermolysis bullosa with congenital absence of skin

Dr Hilary Brown, General Practitioner, Newcastle Skin Check, Newcastle, NSW, Australia. DermNet Editor in Chief: Adjunct A/Prof Dr Amanda Oakley, Dermatologist, Hamilton, New Zealand. Copy edited by Gus Mitchell. September 2019.


What is epidermolysis bullosa with congenital absence of skin?

Epidermolysis bullosa (EB) with congenital absence of skin was previously known as Bart syndrome. It has also been known as 'type VI aplasia cutis congenita and epidermolysis bullosa'.

EB with congenital absence of skin was originally described by Bart in 1966 after observing a family with congenital absence of skin on the lower leg, widespread blistering affecting the skin and mucous membranes, and nail dystrophy [1]. In 1986, Frieden proposed a classification of aplasia cutis congenita in which conditions were classified into nine groups according to location and presence of other anomalies [2]. Bart syndrome was classified as type VI aplasia cutis congenita by its combination of a congenital localised absence of skin, epidermolysis bullosa, and nail dystrophy.

In 2014, a working group of experts in EB suggested a new classification of EB based on molecular features [3]. They suggested the substitution of eponymous names with descriptive terms and recommended Bart syndrome be known as EB with congenital absence of skin.

Who gets epidermolysis bullosa with congenital absence of skin?

EB with congenital absence of skin is rare and the exact incidence is unknown. Aplasia cutis congenita is seen in 1–2 per 10,000 births [4].

EB with congenital absence of skin can be considered a rare form of aplasia cutis congenita, but the proportion of aplasia cutis congenita which can be classified as EB with congenital absence of skin is unknown.

What causes epidermolysis bullosa with congenital absence of skin?

EB with congenital absence of skin is a familial condition with an autosomal dominant pattern of inheritance. Isolated cases have also been recognised [5].

Its aetiology and pathogenesis are still controversial. The genetic abnormality has been associated with chromosome 3 [6,7].

What are the clinical features of epidermolysis bullosa with congenital absence of skin?

EB with congenital absence of skin is a clinical triad.

  1. Congenital absence of skin on the lower extremities
  2. Any type of EB elsewhere on the body
  3. Nail changes such as the congenital absence of nails or nail dystrophy.

The areas of absent skin are usually unilateral and involve the medial and/or dorsal surface of the lower limb. They are sharply demarcated, glistening red areas of ulceration that extend upward from the dorsal and medial surface of the foot and shin [8].

EB with congenital absence of skin may also be associated with other anomalies, such as:

  • Pyloric atresia
  • Rudimentary ear development
  • Flattened nose
  • Broad nasal root
  • Wide-set eyes [5,8].

What are the complications of epidermolysis bullosa with congenital absence of skin?

Complications of EB with congenital absence of skin include infection and haemorrhage. Hypothermia, hypoglycaemia, and disorders of fluid balance may complicate large defects [4,8].

How is epidermolysis bullosa with congenital absence of skin diagnosed?

EB with congenital absence of skin is a clinical diagnosis. Histological evaluation of the skin can help to confirm the diagnosis.

Biopsy reveals a subepidermal blister with an inflammatory infiltrate in the dermis [8]. In some cases, electron microscopy findings of separation of the dermal-epidermal junction and interruption of the basal lamina are similar to that seen in junctional EB [9]. Other case studies have shown the split in the skin to be below the lamina densa on electron microscopy [7].

What is the differential diagnosis for epidermolysis bullosa with congenital absence of skin?

The differential diagnoses of EB with congenital absence of skin include:

  • Other forms of aplasia cutis congenita — aplasia cutis is a rare congenital anomaly characterised by an absence of skin that occurs most commonly on the scalp and cranial vault. The depth of lesions can range from superficial erosion to absence of all skin layers. There are nine subtypes of aplasia cutis congenita; EB with congenital absence of skin has been described as type VI.
  • Other forms of EB — EB is a group of rare inherited disorders characterised by blister formation due to increased skin and mucous membrane fragility. Four major types of EB have been described according to the level of skin cleavage at the ultrastructural level. It is further classified into subtypes based on inheritance, clinical findings, and molecular defects.
  • Adams-Oliver syndrome — Adams-Oliver syndrome is a rare condition characterised by aplasia cutis congenita of the scalp with transverse defects of the limbs and mottling of the skin.

What is the treatment for epidermolysis bullosa with congenital absence of skin?

The management of EB with congenital absence of skin is usually conservative. The aim is to accelerate healing of the affected portions of the skin, to prevent infection or other complications, and to reduce the risk of scarring.

Topical antibacterial ointment and wet dressings are the mainstays of treatment [8]. Prophylactic systemic antibiotics are not recommended. Occasionally surgical intervention with a skin graft or flap repair may be needed for a large defect [9].

What is the outcome for epidermolysis bullosa with congenital absence of skin?

In general, the prognosis of EB with congenital absence of skin is good. Most cases heal well within months with no long-term sequelae [10].

See smartphone apps to check your skin.
[Sponsored content]

 

Related information

 

References

  1. Bart BJ, Gorlin RJ, Anderson VE, et al. Congenital localized absence of skin and associated abnormalities resembling epidermolysis bullosa. A new syndrome. Arch Dermatol 1966; 93: 296–304. PubMed
  2. Frieden IJ. Aplasia cutis congenita: a clinical review and proposal for classification. J Am Acad Dermatol 1986; 14: 646–60. PubMed
  3. Fine JD, Bruckner-Tuderman L, Eady RAJ, et al. Inherited epidermolysis bullosa: Updated recommendations on diagnosis and classification. J Am Acad Dermatol 2014; 70: 1103–26. PubMed
  4. Kuvat SV, Bozkurt M. Conservative treatment of a patient with epidermolysis bullosa presenting as bart syndrome: a case report. Case Rep Med 2010; 2010: 302345. PubMed
  5. Bart BJ, Lussky RC. Bart syndrome with associated anomalies. Am J Perinatol 2005; 22: 365–9. doi: 10.1055/s-2005-871657. PubMed
  6. Christiano AM, Bart BJ, Epstein EH et al. Genetic basis of Bart's syndrome: a glycine substitution mutation in the type VII collagen gene. J Invest Dermatol 1996; 106: 1340–2. doi: 10.1111/1523-1747.ep12349293. PubMed
  7. Zelickson B, Matsumura K, Kist D, et al. Bart's syndrome: ultrastructure and genetic linkage. Arch Dermatol 1995; 131: 663–8. PubMed
  8. Kulalı F, Bas AY, Kale Y et al. Type VI Aplasia Cutis Congenita: Bart’s Syndrome. Case Rep Dermatol Med 2015; 2015: 549825. PubMed Central
  9. Kim DY, Lim HS, Lim SY. Bart Syndrome. Arch Plast Surg 2015; 42: 243–5. PubMed
  10. Alfayez Y, Alsharif S, Santli A. A case of aplasia cutis congenita type VI: Bart Syndrome. Case Rep Dermatol 2017; 9: 112–8. PubMed

On DermNet NZ

Other websites

Books about skin diseases