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Bloom, syndrome
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[MIM 210 900]
(Bloom-Torre-Mackacek syndrome, dwarfism type Levi)
Very rare. Prevalence in the Ashkenazi Jewish population: 1/48.000. Autosomal recessive transmission. Mutations of the 2 copies of the BLM gene on 15q26.1 that codes for a 3'-5' DNA-type RecQ helicase, a protein that plays an essential role in the maintenance of the integrity of the genome.
Syndrome characterized by a high genetic instability with predisposition to the development of all types of cancers.
Clinical picture:
- pre and post-natal growth retardation: harmonious dwarfism (maximal adult stature around 140 cm)
- microcephaly (CP < 2SD) with a long narrow face, micrognathia and retrognathia, sometimes spotty areas of alopecia
- feeding problems in early childhood: lack of appetite, gastroesophageal reflux
- significant reduction of subcutaneous fatty tissue
- "Wolf-mask type" erythema of the face due to the presence of telangiectasia; photosensitivity when exposed to the sun; erythema sometimes extends to the dorsal side of the hands and forerams; sometimes 'café-au-lait' spots
- predisposition to cancers:basal cell carcinoma (BCC), leukemia, lymphoma, breast, colon, etc, that often limit life expectancy (± 30 years)
- immune deficit with sensitivity to infections, particularly pulmonary (bronchiectases)
- ophthalmoscopy: early appearance of druzen (yellowish deposits found between the retinal pigment epithelium and Bruch's membrane)), sometimes non-proliferative diabetic retinopathy
- risk of resistance to insulin: type 2 diabetes, hypothyroidism
Anesthetic implications:
risk of difficult intubation ; peripheral venous access may be difficult (chemotherapy, abnormal subcutaneous tissue); sequelae of chemotherapy; check the respiratory (frequent infections) and thyroid functions. Prevention of infections; glycemic control
References:
Updated: August 2017