Neonatal Sepsis (Case 36)

Chapter 77 Neonatal Sepsis (Case 36)



Christiana R. Farkouh, MD, MPH




Case


A 32-weeks-gestation female infant is born to a 29-year-old G2P1 mother whose serologic test results are:



Blood type A Rh-positive, antibody negative, rapid plasma reagin (RPR) NR, rubella immune, hepatitis B surface antigen (HBsAg) negative, GC/Chlamydia negative, human immunodeficiency virus (HIV) negative, group B streptococcus (GBS) unknown.


Delivery was via an emergency cesarean section due to a nonreassuring fetal heart tracing. The mother was admitted 48 hours before delivery with preterm rupture of membranes and received two doses of betamethasone and antibiotics. Her prenatal history was notable only for antibiotic therapy for an Escherichia coli urinary tract infection (UTI) 1 month before delivery. At 9 hours of life, there is temperature instability, tachypnea, and hypoglycemia.




Differential Diagnosis











Neonatal sepsis Apnea of prematurity (AOP)
Necrotizing enterocolitis (NEC) Neonatal herpes simplex virus (HSV)


Speaking Intelligently


When an infant is admitted after birth with prenatal/perinatal risk factors, or at any time develops clinical symptoms such as fever, hypothermia, glucose intolerance, alterations in respirations , feeding intolerance, or temperature irregularity, I perform a blood culture, complete blood count (CBC) with differential, and C-reactive protein (CRP). I start empiric antibiotic therapy after the blood culture is drawn because the symptoms of neonatal sepsis can be quite subtle and nonspecific, and delay in treatment may be fatal. The CBC, differential, and CRP are repeated at 24 hours. Treatment continues for at least 48 hours despite negative blood culture results. At delivery, however, particularly if mothers have been treated with antibiotics, blood culture results can be unreliable. The initial clinical presentation, response to therapy, presence of risk factors, and laboratory results will all play a role in determining the decision to continue antibiotics beyond the initial 48 hours of evaluation to rule out sepsis.



Patient Care



Clinical Thinking



• Are there maternal or perinatal risk factors?

• What is the infant’s presenting sign(s) or symptom(s)?

• Are there risk factors for sepsis, such as prolonged rupture of membranes, GBS colonization, maternal fever (temperature >38° C [100.4° F])?

• Does the infant have a central line?

• Is there concern for feeding intolerance?

• Has this infant been treated for sepsis previously?


History



• Consider maternal factors such as GBS colonization, maternal GBS UTI, prior children with GBS infection/sepsis.

• Consider perinatal issues such as prolonged rupture of membranes (>16 hours), maternal temperature >38° C (100.4° F), amniotic fluid characteristics, obstetric concern regarding chorioamnionitis.

• Consider neonatal factors such as prematurity, change in baseline clinical status, alterations in respiratory requirements, feeding intolerance, presence of a central line.

• Fever greater than 100.4° F in newborns is unusual and should immediately initiate a full infectious workup including blood, urine, and cerebrospinal fluid (CSF) studies.


Physical Examination



• Vital signs: Hypotension, tachycardia, increased frequency of apnea, increase in desaturation episodes or need for increased respiratory support, fluctuations in body temperature (especially hypothermia in preterm infants) not related to incubator environment.

• Initial assessment should focus on airway, breathing, and circulation (ABCs).

• Abdominal examination: Distention, assessment of bowel sounds, change in residual feed volumes.

• Overall tone and level of activity can be helpful, especially if changed from baseline.


Tests for Consideration



• CBC with differential: Determine ANC, determine the immature to total neutrophil ratio (I:T ratio). Serial levels at 12 and 24 hours may help. $116

• CRP: Serial levels at 12 and 24 hours may help. $69

• Blood culture (both peripheral and from central catheter, if present) $152

• Urine culture and analysis $148

• CSF analysis Gram stain, cell count, for white blood cells (WBCs), red blood cells (RBCs), protein, glucose, and culture $557

• CSF HSV polymerase chain reaction (PCR) $300

• Coagulation studies: Prothrombin time and partial thromboplastin if concern for coagulopathy in disseminated disease $105


Imaging Considerations


→ Chest radiograph $75


→ Abdominal ultrasound (evaluate liver texture and size) $225


→ Brain magnetic resonance imaging (MRI) $900


→ Head computed tomography (CT) scan $750

< div class='tao-gold-member'>

Related posts:

  1. The Special Needs Child
  2. Diarrhea (Case 6)
  3. Pediatric Poisonings (Case 54)
  4. Note Writing

Stay updated, free articles. Join our Telegram channel
Tags:
Jul 18, 2016 | Posted by in PEDIATRICS | Comments Off on Neonatal Sepsis (Case 36)

Full access? Get Clinical Tree
Get Clinical Tree app for offline access