Severe congenital genetic disease characterized by undermineralization of skull and bones, thin ribs, thoracic collapse, multiple fractures, short stature, and prenatal onset. Normal facies accompany this disorder. Clinically, the patient present numerous pathological bone fractures like those affected with the lethal form of osteogenesis imperfecta, but the former can be differentiated by a thin-bone group of lethal dysplasias.
Lethal Type of Brittle Bone Syndrome.
This medical condition was first described in the literature in 1989.
There are only few cases described in the literature. The exact incidence remains unknown.
It is believed inherited as an autosomal recessive inheritance trait with mutations.
There are no clear evidences of a link with a collagen disease. Although in the original case described there was a moderate decrease in type I collagen amount, it was considered insufficient to explain the radiological findings. However, the presence of type V collagen overproduction could play a role in the bone brittleness by interfering with the process of mineralization.
Clinically evocated at birth, or before birth in case of intrauterine growth retardation with fracture.
Bone anomalies include multiple fractures, asymmetry of the body, abnormal ossification. Skeletal deformations concern head and face with unusual Larsen-like facies, including high forehead, microstoma, hypertelorism, flat supraorbital ridges, anteverted nares, broad nasal root, and small nose. Limbs are involved with pes talus, metaphyseal enlargement, overlapping fingers. Other features concern spleen and metabolism anomalies. Respiratory distress is often observed because of thin chest and frequent and multiple ribs fractures.
Precautions before anesthesia
Evaluate phosphocalcic metabolism. Evaluate tracheal intubation (clinical, radiographic) and respiratory function (clinical, chest radiographs, CT scan, pulmonary function tests, arterial blood gas).
It is recommended to consider the airway management particularly difficult during direct laryngoscopy and tracheal intubation because of the microstomia and the increased risk of bone and cartilage fracture. Perioperative respiratory monitoring should be useful because of frequency of respiratory distress. Cautious intraoperative positioning is needed because of skeletal deformation.
Avoid succinylcholine because the risk of fractures during fasciculation.
Other conditions to be considered
☞Osteogenesis Imperfecta (OI, Brittle Bone Disease): Medical condition that is part of a group of that affects mainly bones. Clinically, it is associated with spontaneous pathological bone fractures, without major forces. The severity of the disease varies between mild to severe. Other features include a blue sclerae, short height, increase joint laxity, hearing ...