MBTPS2

IFAP (BRESHECK) Syndrome

Clinical Characteristics
Ocular Features: 

The eyelashes and eyebrow hair is sparse or completely absent.  Keratitis with secondary photophobia is often seen during infancy and progresses to corneal vascularization and scarring, sometimes resembling trachomatous disease.  Cataracts do not seem to be part of this syndrome unlike some other genodermatoses.

Systemic Features: 

Dry, scaly skin and alopecia are usually evident at birth.  There is marked absence of hair throughout the body.  The skin is generally ichthyotic and erythematous, with continuous lamellar desquamation of surface skin.  Generalized follicular hyperkeratosis is present on the scalp, dorsal surface of the limbs and on the abdomen.  Most patients are completely bald.

In some patients the skin, hair and corneal disease is accompanied by severe internal anomalies such as kidney dysplasia, brain anomalies and mental retardation, Hirschsprung disease, cleft palate, external ear malformations, cryptorchidism, and skeletal deformities, a combination of signs that some have called BRESEK/BRESHECK syndrome.  Depending upon how extensive the organ involvement, the prognosis is usually guarded and patients may not live beyond early childhood. 

It is uncertain if IFAP refers to a single disorder or if two disorders are involved (see Genetics).

Genetics

This is generally considered to be an X-linked recessive disorder most likely due to mutations in MBTPS2, at least in patients considered to have the BRESHECK condition.  Female carrier may have some similar skin and hair signs albeit to a lesser degree than males.

Since the amount of MBTPS2 activity has been shown to vary with different mutations, it is possible that all cases of IFAP with or without the added BRESHECK findings are part of the clinical spectrum of a single disorder (variable expressivity).  

Other genodermatoses with severe keratitis are KID syndrome (148210) and Hereditary Mucoepithelial Dysplasia (158310).

Pedigree: 
X-linked recessive, carrier mother
X-linked recessive, father affected
Treatment
Treatment Options: 

No effective treatment is known.

References
Article Title: 

MBTPS2 mutation causes BRESEK/BRESHECK syndrome

Naiki M, Mizuno S, Yamada K, Yamada Y, Kimura R, Oshiro M, Okamoto N, Makita Y, Seishima M, Wakamatsu N. MBTPS2 mutation causes BRESEK/BRESHECK syndrome. Am J Med Genet A. 2012 Jan;158A(1):97-102.

PubMed ID: 
22105905

IFAP syndrome is caused by deficiency in MBTPS2, an intramembrane zinc metalloprotease essential for cholesterol homeostasis and ER stress response

Oeffner F, Fischer G, Happle R, Konig A, Betz RC, Bornholdt D, Neidel U, Boente Mdel C, Redler S, Romero-Gomez J, Salhi A, Vera-Casano A, Weirich C, Grzeschik KH. IFAP syndrome is caused by deficiency in MBTPS2, an intramembrane zinc metalloprotease essential for cholesterol homeostasis and ER stress response. Am J Hum Genet. 2009 Apr;84(4):459-67.

PubMed ID: 
19361614
Subscribe to RSS - MBTPS2