DR Medhat MRCP

Osteogenesis Imperfecta (= brittle bone disease)
- Is a group of disorders of collagen metabolism resulting in bone fragility and fractures.
- The most common, and milder, form of osteogenesis imperfecta is type 1.
Overview
Autosomal dominant
Abnormality in type 1 collagen due to synthesis of pro-α 1 or pro-α 2 collagen
polypeptides
Features
1) Presents in childhood
2) Fractures
3) Blue sclera
4) Deafness 2ndry otosclerosis
5) Opalescent teeth.
Rhabdomyolysis
It will typically feature in the exam as a patient who has had a fall or prolonged
epileptic seizure and is found to have acute renal failure on admission.
Features
- Acute renal failure with disproportionately raised creatinine.
- Elevated CK (thousands).
- Myoglobinuria.
- Hypocalcemia (myoglobin binds calcium).
- Elevated phosphate (released from myocytes)
Causes
1. Seizure
2. Collapse/coma (e.g. Elderly patients collapses at home, found 8 hours later).
3. Ecstasy.
4. Crush injury
5. Mcardle's syndrome.
6. Drugs: statins
Management
1) IV fluids to maintain good urine output.
2) Urinary alkalinization ( I.V Na- bicarbonates )is sometimes used.