Necrotizing enterocolitis Appendicitis Volvulus Incarcerated hernia a Hirschsprung enterocolitis Neurologic disease Infant botulism Shunt obstruction, infection a Child abuse—intracranial hemorrhage a a Indicates more common causes TABLE 73.2 MOST COMMON DISORDERS THAT MIMIC SEPSIS Urinary tract infection Viremia Congestive heart failure Gastroenteritis with dehydration Pertussis causes coughing, apnea, seizures, and death during infancy Parents may report respiratory distress, cough, poor feeding, and vomiting A careful history may reveal that the vomiting is often posttussive History of exposure to pertussis may be lacking because the infant usually acquires the disease from older children or adults who have only symptoms of a common upper respiratory infection Physical examination will distinguish the infection from sepsis if the infant has a paroxysmal cough The characteristic inspiratory “whoop” after a coughing paroxysm (a hallmark in older patients) is uncommon in very young infants Auscultation of the chest is usually normal; tachypnea and cyanosis may be present The classic CBC finding of marked lymphocytosis is often absent in infants with pertussis, and a chest radiograph may not show the typical “shaggy right heart border” in this age group, though atelectasis or pneumonia may be present PCR technique can reliably identify the condition from nasopharyngeal specimens, and nasopharyngeal culture for Bordetella pertussis is confirmatory Infants with congenital syphilis may present in the first weeks of life with extreme irritability, pallor, jaundice, hepatosplenomegaly, and edema Pneumonia, painful limbs, snuffles, and skin lesions are common Consider this diagnosis if a history of maternal infection is obtained or if the child has been chronically ill prior to presentation Radiographs of the infant’s long bones may reveal diffuse