Bruising in premobile children means trouble. The most important take home is: "More than half of premobile infants with initially unexplained bruises were found to be abused." Bruising before they're cruising needs a workup and Department of Child Services (DCS) referral.
Why does this matter?
Often bruises occur in mobile infants. As a matter of fact, bruises on extensor surfaces are expected. But even a single bruise on a premobile infant is abnormal and often indicates abuse. The issue is, when abuse is not detected initially, the injuries to the child will likely continue and get worse and may result in death.
No cruising? No bruising.
This was a prospective study of pediatricians, ED physicians, and child abuse specialists and their evaluation of premobile (<6 months) infants with bruising. 63 infants had explained bruises; 46 had unexplained bruises. After lab, imaging, and follow up, 54% (26/46) of those with unexplained bruises were found to be secondary to abuse. On initial evaluation, 38% of the abused infants had only a single bruise. The largest bruise in 35% of the abused children was <1cm. Put simply, if you don't carefully look for signs of abuse, you'll miss it. This study highlights the fact that in premobile infants, unless there is a clear and plausible explanation for bruising, a more extensive workup with lab, imaging, and child abuse specialist consultation, with DCS referral, is warranted.
A Prospective Study of the Causes of Bruises in Premobile Infants. Pediatr Emerg Care. 2017 Oct 16. doi: 10.1097/PEC.0000000000001311. [Epub ahead of print]
Peer reviewed by Thomas Davis, MD.