Petechiae/purpura in well-appearing infants.

Background: Well infants with petechiae and/or purpura can present to emergency departments, and their management can be difficult. Many will have extensive investigations and treatment that may not be necessary. Methods: This was a retrospective and descriptive audit investigating well infants (<8 months of age) presenting with petechiae or purpura in the absence of fever to a pediatric emergency department over a 9 1/2-year period. All presenting problems of petechiae or purpura were reviewed. Patients were excluded if they appeared unwell, were febrile or have a history of fever, or had eccyhmoses on presentation. Results: Thirty-six babies were identified. The average age was 3.8 months (range, 1-7 months). The majority of the infants had localized purpura/petechiae to the lower limbs (92%) with two thirds of these patients having bilateral signs. None had generalized signs. Most infants had a full blood count (94%), coagulation profile (59%) and C-reactive protein (59%), and blood cultures (59%), with all being normal (except for mild elevation in platelets). Nine patients were admitted for observation, with only 1 patient having progression of signs. This patient had a diagnosis of acute hemorrhagic edema of infancy. The rest of the patients were thought to have either a mechanical reason for their petechiae/purpura (tourniquet phenomena) or a formal diagnosis was not specified. Conclusions: Well infants with localized purpura and/or petechiae with an absence of fever are more likely to have a benign etiology. Further study is required to determine if a full blood count and coagulation profile is necessary, or a period of observation (4 hours) is all that is required. If there is no progression of signs, it is likely that they can be safely discharged. The likely cause may be due to a tourniquet phenomenon (eg, diaper).