congenital cataracts

Marinesco-Sjogren Syndrome

Clinical Characteristics
Ocular Features: 

Congenital cataracts are one of the cardinal features of Marinesco-Sjogren syndrome but lens opacities may have a later onset and may be progressive as well.  Strabismus and nystagmus are sometimes present.

Systemic Features: 

Non-ocular features include cerebellar atrophy, psychomotor developmental delays, mental retardation, and muscle weakness.  Dysarthria is common.  The myopathy has its onset in childhood and is progressive with weakness, hypotonia, and atrophy eventually leading to total disability in some cases.  Progression of motor dysfunction may, however, stabilize in some patients but at an unpredictable level.  Infants are often 'floppy babies'.  MRI studies reveal cerebellar atrophy.  Serum creatine kinase levels are increased and muscle biopsies show chronic myopathic changes.  Skeletal features include short stature, pectus carinatum, and secondary kyphoscoliosis and foot deformities.  Bone abnormalities may be seen in the digits.

Genetics

This is an autosomal recessive condition resulting from mutations in the SIL1 gene (5q31).  It is sometimes confused with the condition known as congenital cataracts, facial dysmorphism, and neuropathy (604168) with which it shares some clinical features.  The two conditions are genetically distinct since they are caused by mutations in different genes.

See also Muscular Dystrophy, Congenital Cataracts, with Cataracts and Intellectual Disability for a similar disorder caused by a different mutation.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

Visually significant cataracts may need to be removed in the first decade of life.  Skeletal deformities may benefit from surgery and hormone therapy should be considered in specific cases.

References
Article Title: 

The gene disrupted in Marinesco-Sjögren syndrome encodes SIL1, an HSPA5 cochaperone

Anttonen AK, Mahjneh I, Hamalainen RH, Lagier-Tourenne C, Kopra O, Waris L, Anttonen M, Joensuu T, Kalimo H, Paetau A, Tranebjaerg L, Chaigne D, Koenig M, Eeg-Olofsson O, Udd B, Somer M, Somer H, Lehesjoki AE. The gene disrupted in Marinesco-Sjogren syndrome encodes SIL1, an HSPA5 cochaperone. Nat Genet. 2005 Dec;37(12):1309-11.

PubMed ID: 
16282978

Linkage to 18qter differentiates two clinically overlapping syndromes: congenital cataracts-facial dysmorphism-neuropathy (CCFDN) syndrome and Marinesco-Sjogren syndrome

Lagier-Tourenne C, Chaigne D, Gong J, Flori J, Mohr M, Ruh D, Christmann D, Flament J, Mandel JL, Koenig M, Dollfus H. Linkage to 18qter differentiates two clinically overlapping syndromes: congenital cataracts-facial dysmorphism-neuropathy (CCFDN) syndrome and Marinesco-Sjogren syndrome. J Med Genet. 2002 Nov;39(11):838-43.

PubMed ID: 
12414825

Cataracts, Congenital, Facial Dysmorphism, and Neuropathy

Clinical Characteristics
Ocular Features: 

Cataracts, microphthalmia, and microcornea (mean diameter ~7.5 mm) are present at birth and precede the onset of neurological symptoms.  The lens opacities often consist of anterior and posterior subcapsular opacities but the entire lens may be opaque as well.  Some adults have bilateral ptosis.  The pupils are often small and have sluggish responses to light and mydriatics.  Strabismus and horizontal pendular nystagmus are common.  Visual impairment may be severe.

Systemic Features: 

The neuropathy is primarily motor and usually begins in the lower extremities but is progressive and eventually involves the arms as well.  Motor development is slow and walking is often unsteady from the start.  Speaking may not have its onset until 3 years of age.   Mild, nonprogresssive cognitive defects and mental retardation are often present.  Sensory neuropathy with numbness and tingling develops in the second decade.  Mild chorea, upper limb tremor, mild ataxia, and extensor plantar responses may be seen.  Deafness has been described.  Nerve conduction studies and biopsies have documented a demyelinating polyneuropathy while MRIs demonstrate cerebral and spinal cord atrophy which may be seen in the first decade of life.  The MRI in many patients reveals diffuse cerebral atrophy, enlargement of the lateral ventricles and focal lesions in subcortical white matter.  Most individuals have mild cognitive deficits while psychometric testing reveals borderline intelligence in a minority.

Patients are susceptible to acute rhabdomyolysis following viral infections.  Most are severely disabled by the third decade.

The facial dysmorphism appears in childhood and consists of a prominent midface, hypognathism, protruding teeth, and thickening of the lips.  Spinal deformities occur in the majority of individuals along with foot and hand claw deformities.  All patients are short in stature.  Hypogonadotropic hypogonadism is a common feature and females may be infertile.  Amenorrhea is often present by the age of 25-35 years.

Genetics

This is an autosomal recessive disorder found primarily among European Gypsies.  It is caused by mutations in the CTDP1 gene (18q23-qter).  It is sometimes confused with Marinesco-Sjogren syndrome (248800) with which it shares some clinical features but the two are genetically distinct.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

Cataracts often require removal in the first decade of life. Scoliosis and foot deformities may benefit from surgical correction.  Supportive care and physical therapy can be helpful.

References
Article Title: 

Linkage to 18qter differentiates two clinically overlapping syndromes: congenital cataracts-facial dysmorphism-neuropathy (CCFDN) syndrome and Marinesco-Sjogren syndrome

Lagier-Tourenne C, Chaigne D, Gong J, Flori J, Mohr M, Ruh D, Christmann D, Flament J, Mandel JL, Koenig M, Dollfus H. Linkage to 18qter differentiates two clinically overlapping syndromes: congenital cataracts-facial dysmorphism-neuropathy (CCFDN) syndrome and Marinesco-Sjogren syndrome. J Med Genet. 2002 Nov;39(11):838-43.

PubMed ID: 
12414825

Congenital cataracts facial dysmorphism neuropathy syndrome, a novel complex genetic disease in Balkan Gypsies: clinical and electrophysiological observations

Tournev I, Kalaydjieva L, Youl B, Ishpekova B, Guergueltcheva V, Kamenov O, Katzarova M, Kamenov Z, Raicheva-Terzieva M, King RH, Romanski K, Petkov R, Schmarov A, Dimitrova G, Popova N, Uzunova M, Milanov S, Petrova J, Petkov Y, Kolarov G, Aneva L, Radeva O, Thomas PK. Congenital cataracts facial dysmorphism neuropathy syndrome, a novel complex genetic disease in Balkan Gypsies: clinical and electrophysiological observations. Ann Neurol. 1999 Jun;45(6):742-50.

PubMed ID: 
10360766

Rhizomelic Chondrodysplasia Punctata

Clinical Characteristics
Ocular Features: 

Congenital cataracts are the outstanding ocular feature of this syndrome and are present in over 70% of patients.  They are usually bilateral and symmetrical and may not be present for several months after birth.

Systemic Features: 

The name of this disorder comes from the punctate calcification seen in cartilage.   The vertebrae have coronal clefting.  The cartilage abnormalities result in defective bone growth with severe growth retardation, short stature, and joint contractures.  Many infants die during the neonatal period and few survive beyond the first decade of life. However, milder forms have been reported. The skin can be ichthyotic and severe mental retardation is often accompanied by seizures.  Red cells are deficient in plasmalogens while phytanic acid and very long chain fatty acids accumulate in the plasma, a biochemical profile characteristic of RCDP1.

Other types of chondrodysplasia punctata also exist (RCDP2 and RCDP3). The X-linked recessive (CDPX1; 302950), autosomal dominant tibia-metacarpal (118651), and humero-metacarpal types are not associated with cataracts.

A phenocopy sometimes results from maternal ingestion of dicoumarol in early pregnancy.

Genetics

This rare autosomal recessive condition results from mutations in the PEX7 gene (6q22-q24) causing a peroxisomal biogenesis disorder.  Some clinical features overlap with those of Zellweger syndrome (214100) and infantile Refsum disease (266510), also peroxisomal biogenesis disorders. 

Mutations in the same gene are responsible for adult Refsum disease-2 (266500).  The latter, however, has other neurological symptoms as well as clinical features of retinitis pigmentosa with night blindness and restricted visual fields.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

No treatment is available beyond supportive measures. Cataract removal may improve vision but the poor prognosis for longevity requires caution be used.

References
Article Title: 

EDICT Syndrome

Clinical Characteristics
Ocular Features: 

This is a rare disorder with multiple anterior segment anomalies.  The corneal stroma is thinned in the range of 330 to 460 um with uniform steepening (no cone).  The epithelium may be irregular and edematous, the stroma is diffusely hazy, and the endothelium is irregular with many guttae.  Anterior polar cataracts are likely congenital and often require removal before the age of 20 years.  The pupils are often eccentric and difficult to dilate.  The iris stroma may appear atrophic.  Visual acuity, even in the aphakic condition, is in the range of 20/30 to 20/160.

Histological studies show attenuation of the endothelium with cellular overlapping and aggregates of fibrillar material that stains for cytokeratin.  Descemet membrane is thickened as is the epithelial basement membrane and both intracellular and extracellular lipid deposition is seen throughout the stroma and the Bowman membrane.

Systemic Features: 

No systemic abnormalities have been reported.

Genetics

This is an autosomal dominant disorder resulting from a heterozygous single base substitution (57C-T) in the MIR184 gene (15q25.1).

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Cataract removal and penetrating keratoplasty can be helpful.  It is unknown whether the donor corneal tissue develops similar opacities.

References
Article Title: 

Pages

Subscribe to RSS - congenital cataracts