Can convulsions alone cause retinal haemorrhages in infants?

AIM

To evaluate the likelihood that, in children under the age of 2 years, convulsions alone may cause retinal haemorrhages.

METHODS

Children under the age of 2 years admitted to hospital following convulsions, were examined within 48 hours of admission. The convulsions were classified by a paediatric neurologist and detailed ocular examination, including indirect ophthalmoscopy, was performed by an ophthalmologist. Statistical analysis was undertaken using Hanley's rule of three.

RESULTS

32 consecutive children admitted with convulsions were examined; 10 of them were admitted following epileptic seizures and 22 following febrile convulsions. Two of the children with febrile convulsions were admitted in status epilepticus. None of these children had retinal haemorrhages. Therefore, using Hanley's rule of three, the upper limit of 95% confidence interval of retinal haemorrhages following convulsions in children under the age of 2 years, is less than 10/100.

CONCLUSIONS

In children under the age of 2 years convulsions alone are unlikely to cause retinal haemorrhages. By combining the results of this study with those previously reported from this unit in older children, the upper limit of 95% confidence interval of retinal haemorrhages, following convulsions in children under the age of 14 years, is less than 5/100. Therefore, the finding of retinal haemorrhages in a child admitted with a history of convulsion should trigger a meticulous search for other causes of these haemorrhages, particularly non-accidental injury.