Bloody cerebrospinal fluid: traumatic tap or child abuse?

A central nervous system dysfunction of nontraumatic etiology was initially suspected in three cases of shaken baby syndrome. Blood contaminating the cerebrospinal fluid was attributed to a traumatic lumbar puncture. Failure to detect retinal hemorrhages contributed to the misdiagnosis. Emergency physicians must consider the diagnosis of shaken baby syndrome in a critically ill infant with bloody cerebrospinal fluid. Ophthalmoscopy should be done routinely in these patients.