Glaucoma, Congenital Primary D

Clinical Characteristics
Ocular Features: 

Evidence of glaucoma can appear in early childhood but may appear much later.  However, typical signs such as enlarged corneas or frank buphthalmos, cloudiness of the corneas, tearing and photophobia are present only when the pressure is elevated due to pupillary block or when the lens migrates into the anterior chamber.  Most patients have additional signs such as ectopia lentis and spherophakia.

Systemic Features: 

Some patients have osteopenia, a high arched palate, and a marfanoid habitus.

Genetics

This form of congenital glaucoma has been described primarily in Middle Eastern and Asian as well as Roma/Gypsy families and is inherited in an autosomal recessive pattern.  The mutations occur in the LTBP2 gene (14q24) which is in close proximity to GLC3C, another putative gene with mutations causing congenital glaucoma. 

Mutations in other genes are also associated with primary congenital glaucoma such as in CYP1B1 causing type A (231300) and in GLC3B causing type B (600975).

THIS IS NOT A PRIMARY GLAUCOMA DISORDER.  Microspherophakia and ectopia lentis are not features of primary congenital glaucoma.  Elevated pressures in these patients are found only when there is a pupillary block or when the lens dislocates into the anterior chamber.  The enlarged cornea is clear and has no breaks in the Descemet membrane.  THIS CONDITION IS THEREFORE RECLASSIFIED AS "MEGALOCORNEA, ECTOPIA LENTIS, AND SPHEROPHAKIA".     

Treatment
Treatment Options: 

The usual surgical and pharmacological treatments for glaucoma apply but vision preservation is a challenge.  The spherophakic or dislocated lenses may need to be removed.

References
Article Title: 

LTBP2 and CYP1B1 mutations and associated ocular phenotypes in the Roma/Gypsy founder population

Azmanov DN, Dimitrova S, Florez L, Cherninkova S, Draganov D, Morar B, Saat R, Juan M, Arostegui JI, Ganguly S, Soodyall H, Chakrabarti S, Padh H, L??pez-Nevot MA, Chernodrinska V, Anguelov B, Majumder P, Angelova L, Kaneva R, Mackey DA, Tournev I, Kalaydjieva L. LTBP2 and CYP1B1 mutations and associated ocular phenotypes in the Roma/Gypsy founder population. Eur J Hum Genet. 2011 Mar;19(3):326-33.

PubMed ID: 
21081970

Null mutations in LTBP2 cause primary congenital glaucoma

Ali M, McKibbin M, Booth A, Parry DA, Jain P, Riazuddin SA, Hejtmancik JF, Khan SN, Firasat S, Shires M, Gilmour DF, Towns K, Murphy AL, Azmanov D, Tournev I, Cherninkova S, Jafri H, Raashid Y, Toomes C, Craig J, Mackey DA, Kalaydjieva L, Riazuddin S, Inglehearn CF. Null mutations in LTBP2 cause primary congenital glaucoma. Am J Hum Genet. 2009 May;84(5):664-71.

PubMed ID: 
19361779

References

Azmanov DN, Dimitrova S, Florez L, Cherninkova S, Draganov D, Morar B, Saat R, Juan M, Arostegui JI, Ganguly S, Soodyall H, Chakrabarti S, Padh H, L??pez-Nevot MA, Chernodrinska V, Anguelov B, Majumder P, Angelova L, Kaneva R, Mackey DA, Tournev I, Kalaydjieva L. LTBP2 and CYP1B1 mutations and associated ocular phenotypes in the Roma/Gypsy founder population. Eur J Hum Genet. 2011 Mar;19(3):326-33.

PubMedID: 21081970

Ali M, McKibbin M, Booth A, Parry DA, Jain P, Riazuddin SA, Hejtmancik JF, Khan SN, Firasat S, Shires M, Gilmour DF, Towns K, Murphy AL, Azmanov D, Tournev I, Cherninkova S, Jafri H, Raashid Y, Toomes C, Craig J, Mackey DA, Kalaydjieva L, Riazuddin S, Inglehearn CF. Null mutations in LTBP2 cause primary congenital glaucoma. Am J Hum Genet. 2009 May;84(5):664-71.

PubMedID: 19361779