What is Toulouse Lautrec syndrome?
Toulouse Lautrec syndrome is a genetic (inherited) recessive bone dysplasia and consistently causes short stature and Osteosclerosis. This is named after the famous French painter Henri de Toulouse-Lautrec who was afflicted with the disease. Adult men with this disease rarely grow taller than 4 feet, 1 inch on an average.
Henri de Toulouse Lautrec
Other names Toulouse Lautrec syndrome : Toulouse Lautrec syndrome can also be called as Pyknodysostosis or Osteopetrosis.
Toulouse Lautrec syndrome is inherited when both parents carry the gene which means autosomal recessive. Both parents must pass on the gene to their child. The odds of both parents carrying the gene conceives a child inheriting both genes and develop this syndrome are 1 in 4.
Symptoms & Signs
- Delays the normal closure of the connections of the skull bones in infancy
- Soft spot on top of the head remains widely open
- The nose is prominent
- The jaw is small
- Front and back of the head are prominent
- Permanent teeth can be slow to appear
- Irregular permanent teeth
- The nails are flat and grooved
- Wrinkled skin on the back of the fingers
- Many smaller bones within the open sutures of the skull
- Front and back of the head are prominent
- Collar bones are often malformed and underdeveloped
- The distal phalanges and the collar undergoes slow progressive deterioration
- Common cavities (4), (6)
Photograph showing broad hand with shortened fingers and spoon –shaped nails
Toulouse Lautrec syndrome is a rare disease. If there is no family history of the disease, the risk for a child to have Toulouse Lautrec syndrome is very low. But, with a consanguineous union the risk of the syndrome rises a little. If one of the parents of the child carries a rare gene like that of pycnodysostosis, the chance of the other rare gene is increased when compared to other. The risks are much higher in a family with a child carrying pycnodysostosis. The parents of the child with the disease may not have signs themselves, but with a given pregnancy, each of the parents has a half chance of transmitting the pycnodysostosis gene verses the normal paired gene. (5)
Connection between Pycnodysostosis and Osteoporosis
Pycnodysostosis is a disease with abnormally dense bones. Whereas Osteoporosis is a disease with washed-out porous bones. But both the diseases cause brittle bones. There is no conceivable connection between Pycnodysostosis and Osteoporosis.
Causes for TLS
Cathapsin K is an essential one for normal osteoclast function. Pyknodysostosis is a lysossomal disorder caused due to the genetic deficiency in Cathepsin K. This has been mapped to chromosome 1q21.
How to diagnose Toulouse Lautrec syndrome?
The diagnosis of Pycodysostosis is based on radiographs and clinical features.
The patients with this syndrome in early childhood can be
- Short stature of limbs
- Delayed closure of cranial sutures
- Occipital bossing and frontal
- Hypoplasia of nails and short broad hands
- Minimal trauma with multiple long bone fractures (4)
The main generalised imaging found in this syndrome is Osteosclerosis with narrowed medullary cavities. Obtuse angle of the mandible and lack or abnormal teeth can also be found. (7), (3)
CT/ Plain radiograph
- Delayed bone age
- Simulating acro-osteolysis
- Partial agenesis
- Aplasia of terminal phalanges
Maxillofacial and Cranial
- Marked delay in sutural closure
- Frontoparietal bossing
- Calvarial thickening
- Persistence of primary teeth
- Relative proptosis
- Nasal beaking
- Wormian bones in lambdoidal region
- Obtuse mandibular gonial angle often with relative prognathism
- Distal clavicles erosion
- Hypoplastic clavicles
- Vertebral segmentation anomalies in upper cervical (C1 and C2) and lower (L5 and S1)
- Increase of lumbar lordosis
- Vertebral body sclerosis
Skull X-ray. The ascending ramus and inferior Hand X-ray showing atrophy of the phalanges
border of the mandible formed a straight line
and all the skull sutures were widely separated
General imaging differential considerations are:
- No clavicle hypoplasia
- No phalangeal
- No delayed closure of cranial sutures
Other sclerosing bone dysplasias (9)
Complications of TLS
As Toulouse Lautrec Syndrome affects bone structure development, in addition to brittle bones and altering normal height development, the patients may also have
- short fingers
- thickening of the bones
- delay and slow development of baby teeth
- Missing adult teeth
- Brittle and thick bones break easily
- The distal phalanges and collarbone of the fingers may slowly deteriorate over time
- Spinal cord develops scoliosis or curvature of the spine
- Bone development on the face and the top of the skull (8), (1)
The life expectancy with Toulouse Lautrec syndrome is normal according to the Hide and Seek foundation. The quality of the life of the patient can be increased with proper dental and medical care.
Quality of life with TLS
Some life areas can limit the quality with debilitating disorder in Toulouse Lautrec syndrome. Individuals with TLS are advised not to participate in contact sports. The most famous sufferer is Henri de Toulouse-Lautrec who went on to be a painter fully active in society of his day.
- Injections of growth hormone improve height
- Plastic surgery helps to correct deformities of the jaw and face
- Dental care for cavities and missing teeth
- Orthodontia for improving the overall look to the teeth
- Exercise like swimming should be limited to low-impact
- Some individuals may need to use wheelchair or crutches to maintain their mobility (2)
Regular checkups and dental hygiene are helpful for preventing complications. Treatment is supportive for fracture prevention and management constituting the aspects of clinical care.
The prognosis for a person with Toulouse Lautrec Syndrome is generally good. The sufferer will be prone to fractures, but with care. Lifespan can be normal or near-normal.
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