Toxic shock syndrome (TSS) is a potentially fatal postoperative complication, and even more so if the diagnosis is delayed. We present the case of a 7-month-old male infant who developed TSS as a complication of tissue expansion using an external port device. There have been 5 documented cases of TSS after tissue expander or breast prosthesis placement occurring in the adult population, however, there has not been a reported case of TSS in an infant. The long interval to development of TSS like symptoms, 4 months in this case, should not exclude TSS from the differential diagnosis. In a pediatric patient, a diffuse macular rash without the severe systemic symptoms on initial presentation can present as a diagnostic challenge. New diagnosis techniques are discussed that can shorten the time to a diagnosis of TSS. In this case, because the local bacterial count was low, the expanded tissue was transferred without complication.