Bone Abstracts

Background: Severe vitamin D deficiency (VDD), is a common disorder, which has complications including rickets, hypocalcaemia, hypotonia, delayed development and cardiomyopathy. Although nutritional rickets associated craniosynostosis has been reported, there is little awareness of this or knowledge about its clinical course or severity. We present five cases of late onset craniosynostosis in association with nutritional rickets.

Clinical presentation: The diagnosis of craniosynostosis was made between the age of 16 months and 3 years (N=5). All children had clinically evident scaphocephaly and radiological evidence of previous rickets. All children had risk factors for severe VDD: Afrocarribean or Asian ethnic backgrounds with darker skin pigmentation (N=5); multiple food intolerances (N=2) and prolonged breast feeding with picky eating habits (N=2). They presented in two ways: Group 1 (N=3) presented with clinical and radiological signs of severe rickets after a long period of untreated severe VDD. Serum 25OH vitamin D concentrations were <20 nmol/l, alkaline phosphatase and parathyroid hormone (PTH) concentrations were elevated and serum calcium and phosphate concentrations were low. They were managed with treatment doses of vitamin D and calcium supplementation where necessary. In two patients, treatment had been completed and clinical signs resolved when the craniosynostosis was diagnosed. Group 2 (N=2) presented with sagittal suture ridging and scaphocephaly associated with resolving rickets on radiology. Clinically there were few other signs of VDD and serum 25OH vitamin D concentrations were 33–44 nmol/l with normal PTH and bone profiles. CT in all cases showed fusion of the sagittal sutures. Three of the children also had multiple suture fusion. All in Group 1 were managed conservatively but Group 2 patients had raised intracranial pressure and both underwent surgical cranial vault remodelling.

Conclusions: All the patients had nutritional rickets associated with craniosynostosis. Patients with late presentation and sagittal suture ridging went on to have emergency cranial vault remodelling. It is important to recognise this complication early and refer to the neurosurgeons and so prevent raised intracranial pressure. It is important to collect detailed data on this and study a larger cohort to raise awareness, establish the pathophysiology and try to prevent this complication.

Disclosure: The authors declared no competing interests.