PEDBASE.org - The Pediatric Database - Detailed information of COHEN SYNDROME

COHEN SYNDROME

DEFINITION:

A rare disorder characterized by infantile hypotonia, childhood obesity, and numerous dysmorphic features.

EPIDEMIOLOGY:

incidence: rare (about 100 cases worldwide)
age of onset:
- infancy (hypotonia)
risk factors:
- familial - autosomal recessive (some sporadic and autosomal dominant cases)
  - chrom.#: 8q
  - gene: ?
- M = F
- Ashkenazi Jews, Finland

PATHOGENESIS:

1. Background

first recognized in 1973
unknown etiology
the Cohen Syndrome gene (CHS1) was assigned to 8q in June 1994 (Tahvanainen et al., Nature Genetics 7:201, 1994)

CLINICAL FEATURES:

1. Neurological Manifestations

1. Infantile Hypotonia (in 90% of cases)

decreased fetal movements
weakness
feeding difficulties
delayed motor milestones
persists into childhood

2. Mental Retardation (in 82% of cases)

mild-moderate
with poor school performance

3. Seizures

occasionally

2. Dysmorphic Features

1. Facial

micrognathia (100%)
short philtrum (90%)
narrow and high-arched palate (90%)
maxillary hypoplasia (82%)
high nasal bridge (65%)
microcephaly (65%)
prominent upper central incisors (62%)
down-slanting palpebral fissures (55%)
protruding dysplastic ears (42%)

2. Musculoskeletal

narrow hands and feet (90%)
joint hypermobility (73%)
cubitus valgus (55%)
genu valgum (48%)
lordosis (45%)
pes planus (42%)
kyphosis (29%)

3. Endocrine Manifestations

% Feature

90 - truncal obesity in mid-childhood

82 - short stature

56 - delayed puberty

? - cryptorchidism, hypoplastic penis and testes

4. Ophthalmologic Manifestations

% Feature

42 - strabismus

33 - myopia

? - constricted visual fields, hemeralopia, nystagmus

chorioretinal dystrophy with bull's eye-like macule and pigmentary deposits
optic atrophy
decreased visual acuity, night and total blindness

INVESTIGATIONS:

1. Serum

granulocytopenia

2. Imaging Studies

1. Skeletal X-Rays

short metacarpals and metatarsals
delayed bone age

MANAGEMENT:

1. Supportive

Paediatrics - moniter hypotonia, feeding difficulties, and developmental delays, promote ambulation and physiotherapy
Dentistry - orthopedic surgery and orthodontic care
Orthopedics - moniter orthopedic complications
Endocrine - moniter stature, puberty, and obesity
Ophthalmo. - moniter ocular manifestations
Genetics - ? prenatal diagnosis, genetic counselling

Pediatric Database - COHEN SYNDROME

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