Ruling out sepsis in an infant with skin patches: How deep to dive?

DR. KRISHNAN is a pediatric cardiology fellow at Children's National Medical Center, Washington, D.C.

DR. ALY is director, newborn services, The George Washington University Hospital, Washington, D.C.

DR. SIBERRY is an assistant professor of pediatrics in the divisions of general pediatric and adolescent medicine and pediatric infectious diseases at Johns Hopkins Hospital, Baltimore.

It's the second week of your internship. Nursery call is just beginning when the neonatal intensive care unit (NICU) transport team arrives with a 12-hour-old baby from a rural hospital two hours away. Immediately, you observe multiple, dark, reddish-brown patches over the baby's trunk, back, and forehead. He appears otherwise healthy, however, and is vigorous.

The baby, you learn, is the 3.3 kg product of a 38-week gestation accomplished by in vitro fertilization. The pregnancy was complicated by gestational diabetes and hyperthyroidism. The mother's prenatal lab tests and screening for group B streptococcus were negative. Delivery was complicated by maternal fever, for which antibiotics were administered. In the delivery room, the on-call pediatrician noted that the baby was in respiratory distress and had multiple skin lesions resembling petechiae and purpura. He was also hypoglycemic, with a blood glucose of 22 mg/dL, which was corrected quickly with intravenous dextrose.

A complete blood count and blood cultures were drawn and antibiotics were started. Because of the rash, the baby was transferred to your NICU to rule out sepsis.

Your initial physical examination yields the following: temperature, 36.9° C; heart rate, 145/min; respirations, 62/min; blood pressure, 75/36 mm Hg; and oxygen saturation, 98% on room air. The baby is alert and pink. Lungs are clear and heart rate is regular.

The remainder of the exam is unremarkable-except for the skin. He has obvious blue discoloration over the nose that does not blanch. There are multiple 2- to 5-mm red-brown patches over the trunk, shoulders, and extremities (Figure 1) and one 3-mm patch on the right forehead. You push on one of the patches; it blanches, and you breathe a sigh of relief. There is a round depression at what you suspect was the site of a scalp electrode.

You study the newborn's chart. Lab tests at birth showed a serum glucose concentration of 22 mg/dL; a CBC with a leukocyte count of 5.8 X 10³/μL (including a differential count of 44% lymphocytes, 27% bands, 22% segmented neutrophils, 6% monocytes, and 1% basophils), and hemoglobin of 16.3 g/dL, hematocrit of 47.9%, and a platelet count of 145 X 10³/μL. You send specimens of blood and cerebrospinal fluid for culture and axillary, nasopharyngeal, rectal, and ear swabs to be tested for herpes simplex virus. The CSF is also sent to the lab for microscopic and chemical analysis.

Several ships at sea

You consider the numbers: Results of CSF analysis are consistent with a traumatic tap, with 13,120/mm³ red blood cells and no white cells. Protein concentration in the cerebrospinal fluid is 276 mg/dL, and glucose concentration is 87 mg/dL. Results of the CSF culture are not back yet.