Epidermolysis Bullosa

Abstract

The article starts with a brief description of Epidermolysis Bullosa followed by basis for classification. Next Symptoms are followed by rare occurrences of the disease concluding with brief management and care.

Epidermolysis Bullosa

Lin and Carter stated that “the name given to a number of genetically determined diseases that share the major characteristics of a tendency to develop blisters and erosions in the skin and sometimes also the mucous membranes is called Epidermolysis bullosa (qtd. by Robin A.J.Eady).”

Historically, Kobner (1886) coined the term “Epidermolysis Bullosa” (EB). Epidermolysis bullosa was classified based on following three factors:

1. Clinical factors such as presence of nail dystrophy, scars, epidermal cysts (milia).
2. Inheritance media
3. Primitive histology.

NHS direct states that the general symptoms of Epidermolysis bullosa (EB) include skin fragility and blistering, in some forms the internal body lining may also be affected along with the cornea in the eye healing with a scar leading to a worst form of disability. Since EB is caused by genetic mutations one form of cannot changeover to another form. EB exists in three forms namely:

1. EB Simplex (EBS): Most common form of EB affecting about 65% people in UK, the skin fragility is restricted to hands and feet. In some forms of EBS blistering occurs in those areas of skin where friction occurs such as the skin under waistbands, bra-straps etc., generally blistering in EBS worsens with heat. EBS is inherited dominantly with the affected passing it to the child.
2. Junctional EB (JEB): JEB is present in about 10% of the total people suffering from EB. The less severe forms occur as skin ulcers and dental problems and life expectancy remains normal, however in more severe form the situation appears grim with extensive loss of skin and malnutrition being major problem. Babies experience anemia and breathing difficulty with ultimate death in first two years. JEB is inherited recessively with each healthy parent contributing one affected gene.
3. Dystrophic EB (DEB): DEB comprises of about 25% of the total people suffering from EB. It may be inherited recessively or dominantly with recessive form being more severe and wide variation in severity in this group. The severe form is recognized by complication in scarring with “the hands being encased in a mitten of scar tissue.” Fragility of the digestive tract with blistering in the mouth and extensive dental problems lead to poor intake of food. Severe DEB may also lead to a complication of skin cancers. In dominant form variable effects are noticed with majority of the people leading a normal life.

But according to Marinkovich recent researches have proposed a new type of EB called hemidesmosomal EB (HEB) producing blisters at the hemidesmosomal level. HEB consists of two rare types of disease namely:

1. EB with muscular dystrophy: It starts with blistering activity and leads to muscular dystrophy at a later stage. There being no correlation between the blistering activity and muscular dystrophy.
2. EB with pyloric atresia: This condition is identified by EB associated with pyloric atresia and severe blistering during birth. The extensive internal involvement leads to poor prognosis despite pyloric atresial correction and may prove to be fatal during infancy.

Lin and Carter stated that various observations made by Gedde-Dahl and Pearson led to the usage and recognition of electron microscopy as the most reliable tool to diagnose and delineate the major types of EB although techniques such as immunofluorescence using monoclonal antibodies have an important role to play in the diagnosis of subtypes of EB. It is implied that trauma induces lesions in EB and hence the term “mechanobullous.”

After discussing about the various types of EB let us discuss some rare occurrences of EB and their implications. Studies conducted by Sidwell et al reported that some infants suffering from Dystrophic epidermolysis bullosa (DEB) developed lethal Dilated Cardiomyopathy (DCM) ultimately leading to death, though the causes were not clear. The possible causes of dilated cardiomyopathy include deficiency of micronutrients particularly Carnitine (Carnitine is a compound with a key role in the transportation of long chain fatty acids into mitochondria where they undergo fatty acid oxidation which is a major source of energy for the heart), Selenium, infections, chronic anemia, iron overload and occurrence of cardiomyopathy as a part of the severe disease process of Recessive dystrophic epidermolysis bullosa (RDEB). The studies concluded that maintaining sufficient Carnitine and Selenium concentrations could lead to reduced occurrence of dilated cardiomyopathy (DCM).

According to Tong et al for patients suffering from EB, ophthalmic complications vary with the subtype. Severe ophthalmic complications could be observed especially in those suffering from dystrophic recessive and junctional subtypes. In a given sample study 51% patients suffering from Dystrophic EB (autosomal recessive) reported ocular complications and 14% reported symptoms suggestive of recurrent corneal erosions.

On the other hand ocular lesions were found in 40% patients suffering from Junctional EB with corneal scarring. The management is case dependent and conservative with ocular lubricants. “Patients with exposure keratitis are most difficult to manage and require the most frequent follow up. Both ectropion and severe symblepharon can cause exposure or lagophthalmos. Some patients with blistering and induration of the upper lid have a mild lagophthalmos nocturnally.”

Hsieh et al stated that common clinical feature of those suffering from recessive dystrophic epidermolysis bullosa (RDEB) was constipation. The gastrointestinal manifestations include dysphagia, esophageal stricture, growth failure such as esophageal web, constipation and anal lesions.

According to Kane and Johnson management of EB is palliative in the following way:

1. Soft well fitted shoes may be used to avoid warm temperatures and minimize bullae formation and avoid traumatic activities.
2. Aseptic aspiration of blister fluid and careful trimming with sterile scissors could avoid extensive bullae.
3. Secondary infection can be avoided by daily baths using gentle cleansers such as Aquanil or Cetaphil liquid cleansers and topical petrolatum impregnated gauze.
4. Usage of topical emollients such as Vaseline petroleum jelly, hydrated petrolatum or aquaphor healing ointment in friction areas can help reduce friction.
5. In case of bacterial infection topical antibiotics such as bactroban, bacitracin, neosporin or polysporin can be used.

In concluding remarks I would like to state that EB is a hereditary disease and can be managed with the above few steps mentioned, but in severe cases it may lead to death of infants and studies are in progress to detect the disease in womb and prevent.

References

Andrew N. Lin and D. Martin Carter (1992). Epidermolysis Bullosa: Basic and Clinical Aspects. Published by Springer.

Kay Shou-Mei Kane, Jen Bissonette Ryder, Richard Allen Johnson, Howard P. Baden and Alexander Stratigos (2001). Color Atlas & Synopsis of Pediatric Dermatology. Published by McGraw-Hill Professional.

NHS Direct. Epidermolysis bullosa (EB). Symptoms. Health encyclopaedia. Page retrieved on November 19, 2006 from: http://www.nhsdirect.nhs.uk/articles/article.aspx?articleId=560&sectionId=8201

M Peter Marinkovich and Ngoc Pham (2006). Epidermolysis Bullosa. Page retrieved on November 19, 2006 from: http://www.emedicine.com/derm/topic124.htm

R U Sidwell, R Yates and D Atherton (2000). Dilated cardiomyopathy in dystrophic epidermolysis bullosa.Arch. Dis. Child. Vol. 83; pp.no.59-63. Page retrieved on November 15, 2006 from: http://adc.bmj.com/cgi/reprint/83/1/59

L Tong, P R Hodgkins, J Denyer, D Brosnahan, J Harper, I Russell-Eggitt, D S I Taylor and D Atherton (1999). The eye in epidermolysis bullosa. Br J Ophthalmol. Vol. 83;pp.no.323–326. Page retrieved on November 15, 2006 from: http://bjo.bmj.com/cgi/reprint/83/3/323

Chih-Hsin Hsieh, Che-Jen Huang and Gau-Tyan Lin (2006). Death from colonic disease in epidermolysis bullosa dystrophica. BMC Dermatology. Vol.6 number 2. Page retrieved on November 15, 2006 from: http://www.biomedcentral.com/content/pdf/1471-5945-6-2.pdf