'Immigrant-Ricketts' – an important differential diagnosis in neonatal seizures

Introduction: Neonatal ricketts is a rare manifestation of calcipenic vitamin-D-ricketts. Hypocalcemic epileptic seizures may be the presenting symptoms.

Case report: The child of unrelated, healthy parents of eritrean origin presented at the age of 8 days with series of mainly left-sided cloni of 5–10min duration. Laboratory analyses showed hypocalcemia, hypophosphatemia, a marked elevation of alkaline phosphatase and paratthyroid hormone. Radiographic imaging revealed an enlargement of the tibial ephiphyses, osteopenia and swollen costochondral junctions of the rips. The mother of the child also had hypocalcemia, hypoparathyreoidism and a low vitamin-D3 concentration as well as osteopenia. The epileptic seizures of the child were easily controlled by calciumgluconate intravenously. High dosage vitamin-D3-, calcium- and phosphate-substitution was followed by a prompt regression of the clinical signs of ricketts within a few weeks.

Discussion: Normal fetal and neonatal calcium homeostasis is dependent on a sufficient maternal supply with calcium. Risk groups for a maternal vitamin-D-deficiency are persons on “alternative diets“ and immigrants from africa and asia. Relevant factors for a disease manifestation are:

• Diet rich in fibers and leguminous plants, impairing intestinal vitamin-D absorption.

• Reduced dermal vitamin-D synthesis due to low sun exposure in the new country (potentiated by socio-cultural habits and religious dress-codes).

Conclusion: Neonatal epileptic seizures due to ricketts-induced hypocalcemia have an excellent prognosis when causal therapy is promptly initiated. Facing growing migration from sun-exposed to sun-deprived countries neonatal ricketts should be considered as an important differential diagnosis of neonatal seizures.