Kenny-Caffey syndrome type 2

Other Names: KCS2; Dwarfism, cortical thickening of tubular bones and transient hypocalcemia; Kenny-Caffey syndrome, autosomal dominant

Kenny-Caffey syndrome type 2 is a genetic disorder that affects the skeleton, head, and eyes. It causes frequent episodes of low blood calcium (hypocalcemia).

Cause

This syndrome is caused by changes (pathogenic variants) in the FAM111A gene.

Inheritance

Autosomal dominant pattern, a 50/50 chance.

It is inherited in an autosomal dominant pattern.

Signs and symptoms

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. 80%-99% of people have these symptoms

• Cortical thickening of long bone diaphyses
• Delayed cranial suture closure
• Short stature(Decreased body height)
• Stenosis of the medullary cavity of the long bones

30%-79% of people have these symptoms

• Abnormal circulating follicle-stimulating hormone level
• Anemia(Low number of red blood cells or hemoglobin)
• Basal ganglia calcification
• Bilateral microphthalmos(Abnormally small eyeball on both sides)
• Calvarial osteosclerosis
• Carious teeth(Dental cavities)
• Congenital hypoparathyroidism
• Decreased skull ossification(Decreased bone formation of skull)
• Decreased testicular size(Small testes)
• Delayed skeletal maturation(Delayed bone maturation)
• Hypermetropia(Farsightedness)
• Hyperphosphatemia(High blood phosphate levels)
• Hypertelorism(Wide-set eyes)
• Hypocalcemic seizures(Low calcium seizures)
• Hypocalcemic tetany
• Intrauterine growth retardation(Prenatal growth deficiency)
• Papilledema
• Postnatal growth retardation(Growth delay as children)
• Postnatal macrocephaly
• Prominent forehead(Pronounced forehead)
• Retinal calcification
• Thin long bone diaphyses(Thin shaft of long bone)

5%-29% of people have these symptoms

• Developmental cataract(Clouding of the lens of the eye at birth)
• High pitched voice
• Persistence of primary teeth(Delayed loss of baby teeth)

Treatment

Treatment often includes calcium and vitamin D supplements and addressing any medical issues as they occur.

NIH genetic and rare disease info

• NIH info on Kenny-Caffey syndrome type 2

Kenny-Caffey syndrome type 2 is a rare disease.