NUR 636 Module 5 Case Study Example

Case Study: Applying the 2021 AAP Guideline to a Well-Appearing Febrile Infant at 35 Days

[Student Name]

Southern New Hampshire University

NUR 636: Primary Care of Infants, Children and Adolescents

Module Five Case Study

[Instructor Name]

[Date]

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Case Study: Applying the 2021 AAP Guideline to a Well-Appearing Febrile Infant at 35 Days

A fever in an infant under two months old used to trigger the same response almost everywhere: blood, urine and spinal fluid tests, antibiotics and hospital admission. Most of those infants turned out to have viral illnesses, and many were exposed to painful procedures, antibiotics and separation from their families for little benefit. Yet a small number have serious bacterial infections that can be devastating if missed. In 2021 the American Academy of Pediatrics published its first guideline for evaluating well-appearing febrile infants aged 8 to 60 days. This case study applies it to a five-week-old seen in primary care and argues that following its age-specific pathway allows a careful clinician to spare a low-risk infant unnecessary procedures without missing the infants who need them.

The Case

Sofia is a 35-day-old girl brought to the clinic at 10 a.m. Her mother noticed she felt warm at 7 a.m. and measured a rectal temperature of 38.3 degrees Celsius. She has been breastfeeding every two to three hours as usual, has had six wet diapers since midnight and cried normally during the night. Her four-year-old brother has a cold. She arrived vaginally at 39 weeks' gestation after an uncomplicated pregnancy; her mother's group B streptococcus screen was negative, and neither received antibiotics around delivery. She has never been hospitalized and has received no antibiotics. In the clinic, her rectal temperature is 38.2 degrees Celsius, heart rate 162, respiratory rate 40 and oxygen saturation 98%. She is alert, makes eye contact, feeds vigorously during the visit and is consolable. Her fontanelle is flat, skin is pink without rash or petechiae, capillary refill is under two seconds and the rest of her examination is normal apart from mild nasal congestion.

Why Age Matters

Serious bacterial infections in young infants are now mostly urinary tract infections. In a population study of term infants aged one week to three months, urinary tract infections far outnumbered bacteremia and meningitis, Escherichia coli was the leading cause of all three and most bacteremia occurred alongside a urinary infection (Greenhow et al., 2014). The risk of bacteremia and meningitis is highest in the first weeks of life and falls with age, which is why the AAP guideline divides well-appearing febrile infants into three bands, 8 to 21 days, 22 to 28 days and 29 to 60 days, with progressively less invasive evaluation (Pantell et al., 2021). Sofia, at 35 days, falls in the oldest band. The guideline applies only to well-appearing infants born at 37 weeks or later with a documented temperature of 38.0 degrees Celsius or higher, without prior antibiotics, focal bacterial infection or complex medical conditions, and she meets each condition.

Applying the Guideline

For well-appearing infants 29 to 60 days old, the guideline directs clinicians to obtain a urinalysis, a blood culture and inflammatory markers, with procalcitonin preferred, and to use the results to decide whether lumbar puncture and antibiotics are needed (Pantell et al., 2021). Sofia's catheterized urinalysis showed no leukocyte esterase, no nitrites and fewer than five white cells per high-power field; urine was sent for culture. Her procalcitonin was 0.18 ng/mL, her C-reactive protein 6 mg/L, her absolute neutrophil count 3,200 per microliter and her temperature never exceeded 38.5 degrees Celsius. All fall within the ranges the guideline treats as reassuring. A blood culture was drawn.

A validated prediction rule supports the same conclusion. In a multicenter study of febrile infants 60 days or younger, a rule combining a negative urinalysis, an absolute neutrophil count of 4,090 per microliter or less and a procalcitonin of 1.71 ng/mL or less identified infants at low risk of serious bacterial infection with very high sensitivity in both derivation and validation sets (Kuppermann et al., 2019). Sofia meets all three low-risk criteria.

What Is Not Done and Why

For an infant in this age band with a negative urinalysis and reassuring inflammatory markers, the guideline indicates that a lumbar puncture need not be performed and that antibiotics need not be started, because the probability of meningitis is very low. Avoiding the lumbar puncture spares Sofia a painful procedure that sometimes requires several attempts, and avoiding empiric antibiotics prevents unnecessary exposure and the admission that often accompanies it. Viral testing for her congestion could be considered but would not change management, since a positive viral test does not remove the need to assess bacterial risk in this age group.

Home Observation Plan

Infants in this age band with reassuring results may be observed at home if the family can reliably monitor the infant and return, with follow-up within 24 to 36 hours (Pantell et al., 2021). Sofia's mother has a working phone and a car, lives 15 minutes from the clinic and understands the plan, so home observation is appropriate. The plan includes checking the blood and urine cultures at 24 and 36 hours, with the clinic calling the family immediately if either grows bacteria; a clinic recheck tomorrow morning; and clear instructions to return at once or call 911 if Sofia becomes difficult to wake, feeds poorly or refuses two feedings, has fewer than four wet diapers in 24 hours, develops a rash that does not blanch, breathes fast or with effort or has a temperature of 38.5 degrees Celsius or higher. Acetaminophen was not recommended before the recheck, so that fever trends remain visible.

Communicating With the Family

Sofia's mother was frightened when told that fever in young infants is taken seriously. The explanation focused on what the tests showed: her urine was clear, the blood markers of infection were low and a well-validated set of criteria placed Sofia at very low risk. She was told honestly that the cultures take time and that the plan depends on her watching closely and bringing Sofia back if anything changes. She repeated the return precautions back correctly.

Conclusion

Sofia is a well-appearing, term, 35-day-old infant with fever, a negative urinalysis and reassuring inflammatory markers. Applying the 2021 AAP guideline for her age band, supported by a validated prediction rule, allows her to avoid a lumbar puncture, antibiotics and admission, while cultures, a recheck and specific return precautions guard against the rare infection that could still emerge.

References

Greenhow, T. L., Hung, Y.-Y., Herz, A. M., Losada, E., & Pantell, R. H. (2014). The changing epidemiology of serious bacterial infections in young infants. Pediatric Infectious Disease Journal, 33(6), 595-599. https://doi.org/10.1097/INF.0000000000000225

Kuppermann, N., Dayan, P. S., Levine, D. A., Vitale, M., Tzimenatos, L., Tunik, M. G., Saunders, M., Ruddy, R. M., Roosevelt, G., Rogers, A. J., Powell, E. C., Nigrovic, L. E., Muenzer, J., Linakis, J. G., Grisanti, K., Jaffe, D. M., Hoyle, J. D., Greenberg, R., Gattu, R., . . . Mahajan, P. (2019). A clinical prediction rule to identify febrile infants 60 days and younger at low risk for serious bacterial infections. JAMA Pediatrics, 173(4), 342-351. https://doi.org/10.1001/jamapediatrics.2018.5501

Pantell, R. H., Roberts, K. B., Adams, W. G., Dreyer, B. P., Kuppermann, N., O'Leary, S. T., Okechukwu, K., Woods, C. R., Byington, C. L., Lavelle, J. M., Lye, P. S., Macy, M. L., Munoz, F. M., Nelson, C. E., Pearson, S. J., Powell, K. R., & Teichman, J. S. (2021). Evaluation and management of well-appearing febrile infants 8 to 60 days old. Pediatrics, 148(2), Article e2021052228. https://doi.org/10.1542/peds.2021-052228