CHAPTER 73 ■ SEPTIC-APPEARING INFANT STEVEN M SELBST, BRENT D ROGERS INTRODUCTION A young infant may be brought to the emergency department (ED) because he or she “just doesn’t look right” to the parents Inexperienced parents will notice when their newborn is unusually sleepy, fussy, or not drinking well To the clinician, such an infant may appear quite ill with pallor, cyanosis, or ashen color, and have noted irritability, lethargy, fever, or hypothermia Tachypnea, tachycardia, hypotension, or signs of poor perfusion may also be apparent Generally, an ill-appearing infant will be immediately thought to have sepsis and managed reflexively Although this is the correct approach, several other conditions can produce a septic-appearing infant This chapter establishes a differential diagnosis for infants in the first months of life who appear ill An approach to the evaluation of such infants is discussed DIFFERENTIAL DIAGNOSIS Numerous disorders ( Table 73.1 ) may cause an infant to appear septic The most common of these diseases ( Table 73.2 ) include bacterial and viral infections The remaining disorders demand diagnostic consideration because although uncommon, they are potentially life-threatening and treatable Sepsis Sepsis should always be considered when managing an ill-appearing infant (see Chapters A General Approach to the Ill or Injured Child , 10 Shock , and 94 Infectious Disease Emergencies ) The signs and symptoms of sepsis may be subtle, and include lethargy, irritability, diarrhea, vomiting, and anorexia Fever is often present, but some septic infants younger than months will be hypothermic instead (See ED Clinical Pathway for Evaluation/Treatment of Febrile Young Infants (0-56 Days Old); https://www.chop.edu/clinical-pathway/febrile-infantemergent-evaluation-clinical-pathway ) The history may vary, and some infants are ill for several days whereas others deteriorate rapidly On physical examination, a septic infant may be pale, ashen, or cyanotic with cool and mottled skin due to poor perfusion The infant may be lethargic, obtunded, or irritable There is often marked tachycardia, (heart rate approaching 200 beats per minute) and tachypnea (respiratory rate more than 60 breaths per minute) If disseminated intravascular coagulopathy (DIC) has developed, scattered petechiae or purpura