Toulouse Lautrec Syndrome

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.

Inheritance

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

Risk factors

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.

Clinical presentation

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⁾

Radiographic features

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

Hands

• 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

Others

• 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

Differential diagnosis

General imaging differential considerations are:

Osteopetrosis

• 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)}

Life expectancy

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.

Treatment

• 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⁾

Prevention

Regular checkups and dental hygiene are helpful for preventing complications. Treatment is supportive for fracture prevention and management constituting the aspects of clinical care.

Prognosis

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.

References:

1. Avon SL. Forensic odontology: The roles and responsibilities of the dentist. J Can Dent Assoc.2004;70(7):453–8
2. Beighton P, Beighton G 1986 The Man Behind the Syndrome. Spinger-Verlag; p. 231.
3. Fleming KW, Barest G, Sakai O. Dental and facial bone abnormalities in pyknodysostosis: CT findings. AJNR Am J Neuroradiol. 2007;28 (1): 132-4
4. Gelb BD, Shi GP, Chapman HA et-al. Pycnodysostosis, a lysosomal disease caused by cathepsin K deficiency. Science. 1996;273 (5279): 1236-8
5. Gelb BD, Willner JD, Cunn TM, Kardon NB, Berloes A, Poncin J, Desnick RJ, 1998 Paternal uniparental disomy for chromosome 1 revealed by molecular analysis of a patient with pycnodysostosis. Amer J Hum Genet 62: 848-854.
6. Motyckova, G; Fisher, DE (2002). “Pycnodysostosis: role and regulation of cathepsin K deficiency in osteoclast function and human disease”. Current Molecular Medicine. 2 (5): 407–421.
7. Nguyen BD, Ram PC. AJR Teaching File: multiple symmetric abnormalities in a radionuclide bone scan. AJR Am J Roentgenol. 2007;189 (3): S32-4.
8. Soliman AT, Rajab A, Al Salmi I, Darwish A, Asfour M, 1996 Defective growth hormone secretion in children with pycnodysostosis and improved linear growth after growth hormone treatment. Arch Dis Childh 75: 242-244.
9. Spranger JW, Brill PW, Poznanski AK. Bone dysplasias, an atlas of genetic disorders of skeletal development. Oxford University Press, USA. (2002) ISBN:0195214749.