Tuberous sclerosis
Tuberous sclerosis is also known as epiloia. It is an autosomal dominant disorder with variable penetration affecting 1 in 7000 babies. But at least 75% are due to fresh mutation. It is genetically heterogenous with one disease gene on chromosome 9 and a second disease gene on chromosome 16. Seems that the clinical expression is variable, the diagnosis may be delayed, mainly made during the first decade. Male and female carries the same predominant; however, autism is more common in males. Severity and expression of the syndrome varies enormously even within families. Usually patient will present with epilepsy or recurrent seizures. Mental deficiency is variable. Some skin manifestations are seen. All have granulomatous lesions (tubers) in the brain which become visible on CT scan by 7 or 8 years of age. Skin manifestations include the typical facial angiofibromas or adenoma sebaceum (a popular rash on the cheeks), ungual fibromas, shagreen patch and cafe au lait spots. Depigmented ash leaf shaped macules can also be found over the trunk and extremities which are better seen on examination with Wood’s light. Visceral hamartomas and retinal lesions are common.
Tuberous sclerosis is a multisystem disease. It does not only affect the skin and the brain, but may also involve other organs like heart, kidney and the lungs.
Diagnosis mainly made by MRI or CT scan of the brain. With gandolinium contrast, MRI may provide more characteristic subepyndymal nodules and cortical white matter tubers. Electroencephalogram (EEG) is abnormal. Other diagnostic procedures used are biopsy of indeterminate lesions, renal ultrasound or CT scan and echocardiography. Molecular testing generally available for research purpose only.
Management is mainly symptomatic. Child with mental retardation will be sent to special school. Prophylactic anticonvulsant therapy will be given to those with recurrent seizure. Antibiotic prophylaxis may be indicated for patient going for surgery. They may take part with most activities depending on the degree and complexity of the disease. Supervision is needed in certain activities for example during swimming. It may be wise to stay away from dangerous activity like rock climbing and canoeing. During adulthood, they should be at least 2 years fit free before applying for driving license. Occasionally, surgical excision of tumors may be done depending on the site and size of the tumor. Those with family history of tuberous sclerosis are at risk so genetic counseling is given when appropriate.
*Tips for medical student – this case often come out as a short case.
SUMMARY OF SIGNS AND SYMPTOMS
- Most cases will have facial angiofibomata (adenoma sebaceum) and present as a facial lesion in a butterfly contribution (80% of cases)
- Hypopigmented areas mainly over the trunk and extremities (ash leaf spots). This is often present as first sign at birth or shortly after (50% of cases)
- Seizures disorder including myoclonic seizure (90% of cases)
- Renal cysts (50-80%)
- Pulmonary lymphangiomatosis (<10%)
- CNS periventricular calcifications (50-80% of cases)
- Retinal astrocytomas and hamartomas (50-80% of cases)
- Cardiac rhabdomyomas (50% of cases)
- Mental retardation (60-70%)
- Autism (10-20%)
- Multiple ungual fibromas (20% of cases)
- Dental pits
- Liver hamartomas (10% of cases)
Reference:
- Shyam Bhakthavalsala et al. Crash Course Paediatrics. Third edition. 2008. Mosby Elsevier.
- Simon J Newell et al. Lecture notes paediatrics. 8th edition. 2008. Blackwell Publishing.
- MarkR Dambro et al. Griffith’s 5 Minute Clinical Consult. 2005.
- Paediatrics Colour Guide. Mosby Elsevier.
Tags: adenoma sebaceum, ash leaf spots, seizure, shagreen patch, tuberous sclerosis
Technorati Tags: adenoma sebaceum, ash leaf spots, seizure, shagreen patch, tuberous sclerosis
This is a very informative post. This tells us that we should really be careful and we should protect our children.