1. Spider nevus It is also called a spider angioma or a Nevus areneus. These are common acquired vascular lesions present in over 1O% of healthy adults. They are typically occur in the distribution of the superior vena cava, that is the face, neck, upper chest & upper arms. During pregnancy, they often occur & spontaneously resolve postpartum. Treatment is either with electrodessication or laser. Causes of spider nevi: @ pregnancy. @ Oral contraceptive pills. @ liver disease Spider nevi are not associated with prematurely, although they are more common in children & women.

2. Spider nevus

3. Ataxia telengiectasia Louis Bar syndrome It is a rare neurodegenerative inherited disease (autosomal recessive fashion due to mutation in the ATM gene). A-T affects many parts of the body: 1. It impairs certain areas of the brain cerebellum causing difficulty with movement & coordination. The patient appears as if drunken when walking 2. Oculocutaneous telengiectasia. The patient develop difficulty in moving the eyes in a natural manner. 3. It weakens the immune system causing a predisposition to recurrent sinusitis & pulmonary infections. 4. It prevents repair of broken DNA increasing the risk of cancer 5. Hypersensitivity to ionizing radiation 6. Increase risk of malignancy especially lymphoma & leukemia 7. Thymic hypoplasia There is no specific treatment for A-T, most patients die as young adults from infection or malignancy.

4. Ataxia telangiectasia

5. Chromosomal breakage syndrome OR DNA repair disorders Chromosomal instability can occur when the DNA damage response & repair process fails resulting in syndromes characterized by growth abnormalities, hemopoeitic defect, mutagen sensitivity & cancer production. Chromosomal breakage syndrome can be seen in: @ Ataxia telengierctasia @ Xeroderma pigmentosa @ Fanconi’s anemia @ Nijmegen breakage syndrome @ Bloom syndrome @ Cockayne syndrome @ Trichothiodystrophy