RT Book, Section A1 Morley, Keith W. A1 Pride, Howard B. A2 Zaoutis, Lisa B. A2 Chiang, Vincent W. SR Print(0) ID 1146119300 T1 Skin and Soft Tissue Infections T2 Comprehensive Pediatric Hospital Medicine, 2e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9780071829281 LK accesspediatrics.mhmedical.com/content.aspx?aid=1146119300 RD 2024/10/12 AB Intact skin serves as an effective mechanical barrier in the vast majority of healthy infants and children. Constant desquamation continually removes potentially invasive bacteria; however, almost any microorganism can live upon human skin under appropriate conditions.1 It is helpful to view these in the framework of transient, resident, and pathogenic flora. Transient flora are microorganisms deposited on the skin from the environment, typically non-proliferative and easily removed by washing the affected region. Resident flora are a select group of organisms regularly found on the skin of normal individuals in appreciable numbers that form stably reproducing colonies and that are not easily dislodged. The resident flora consists primarily of gram-positive species such as Propionibacterium acnes, aerobic diphtheroids, and Staphylococcus epidermidis. A few gram-negative species such as Escherichia, Enterobacter, Proteus, and Pseudomonas are found uncommonly on normal skin, more likely being found in moist intertriginous regions such as the groin and toe webs.1 Pathogenic organisms are not ordinarily found as part of the resident flora but may persist via continuous replacement from either an internal or external nidus of infection and include a wide range of organisms, most commonly, Staphylococcus aureus and group A β-hemolytic Streptococcus (GABHS).