JEB inversa, late onset JEB and larygo-onycho-cutaneous syndrome are caused by mutations in the laminin-332 gene. JEB inversa presents at birth with erosions localized to intertriginous areas such as the groin, neck and axillae. Although milia are not common, scarring and nail dystrophy frequently are observed. Oral erosions may occur, and dental enamel hypoplasia and dental caries may be more common. With the exception of pyloric atresia, which may occur, other systemic findings such as poor growth, anemia, and blistering and other problems involving the trachea/respiratory tract, genitourinary tract and eyes are not seen. There is no increased risk of skin cancer.
Late-onset JEB, also known as EB progressiva, typically presents after childhood with blisters and erosions. Nail dystrophy is common, but milia and scarring typically are not seen. Increased sweating (hyperhidrosis) and absence of fingerprints (adermatoglyphia) are reported. Oral erosions and dental enamel problems may be seen, but there does not appear to be an increased incidence of dental caries. Affected persons typically do not develop poor growth, anemia or problems with the trachea/respiratory tract, intestines/gastrointestinal tract, eyes or genitourinary tract. There is no increased risk of skin cancer.
Laryngo-oculo-cutaneous syndrome (LOC), or Shabbir’s syndrome, presents at birth with blistering and erosions that typically favors the head and neck. Nail dystrophy and granulation tissue commonly are observed, while milia and scarring are less common. LOC is predominantly reported in the state of Punjab, India. Oral erosions, dental enamel problems, dental caries, and ocular (eye) erosions and other complications are common. Laryngeal erosions and related complications are a key feature and may lead to airway obstruction and death. Growth retardation and anemia may occur, but problems with the intestines/gastrointestinal tract or genitourinary tract have not been reported. There is no increased risk of skin cancer.