Case Recap:
A 40-day-old girl presents to the ED in January for evaluation of a rectal temperature of 38?C (100.4?F). The history and physical examination are similar to an infant you saw in August, except that she has nasal discharge and a cough. Which risk stratification algorithm should you use for this infant? Would your workup change if a respiratory swab was positive for respiratory syncytial virus?
Case Conclusion:
Although the 40-day-old infant?s signs and symptoms were suggestive of a benign URI, you remembered that several studies demonstrated that infants in this age group (29-56 days) with documented RSV or influenza are still at risk for SBI, especially UTI, though the risk of IBI is lower in this age group compared with infants who have negative RSV or influenza testing. You ordered urine studies, blood culture, CBC, CRP, and PCT, given the non-negligible prevalence of IBI. The urinalysis was normal, the CBC showed a WBC of 10,000/mcL, the CRP was < 20 mg/L, the PCT was < 0.5 ng/mL, and the ANC was < 10,000 cells/mcL. Since the girl’s labs were reassuring and she was well appearing and feeding appropriately with reliable followup, you discharged her home without CSF testing and with close primary care follow-up the next day.
Did you get it right?
Last Updated on January 26, 2023
Can you please comment on the range of ANC in infants as less than 10,000 is a value if patient is symptomatic than what to do? should we prescribed antibiotics ?
Some times with the passage of time if fever not settled than do we have to repeat the cbc?
From Pediatric Emergency Medicine Practice
Evaluation and Management of the Febrile Young Infant in the Emergency Department issue
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Special Circumstances
Fever at Home Reported but Afebrile in the Emergency Department
A commonly encountered situation is an infant with a reported rectal temperature of > 38?C at home who did not receive antipyretics but is afebrile in the ED. Similarly, an infant may present with a history of fever taken by an axillary measurement or other method, or who ?felt warm.? Do these infants warrant the same workup as an infant with a documented fever in the ED? While data are somewhat limited to guide management in these situations, febrile infants are at higher risk for SBI, so it is prudent to maintain a low threshold to evaluate for these infections. A retrospective study reported that 92% of infants whose caretakers had documented a rectally obtained temperature at home were febrile in the subsequent 48 hours, while only 46% of infants with tactile fever at home had documented fever during their ED or hospital stay. Additionally, only 1 of the 26 infants with tactile fever at home who were also afebrile in the ED had an SBI (UTI), and none of the 26 had an IBI. Two studies reported recently that the incidence of SBI and IBI was similar for infants who were febrile in the ED and for infants with a reported fever at home but who were afebrile in the ED. Additionally, Woll et al found that 17% of infants with bacteremia and/or bacterial meningitis had a history of fever at home but not in the ED.80 Therefore, evaluation of infants with documented fever at home requires the same evaluation as infants who are febrile in the ED. Of note, a 2019 study that derived and internally validated a prediction model to identify febrile infants at low risk for IBI found that infants with a history of fever at home but who were afebrile in ED had a low probability of IBI if their urinalysis was normal and their ANC was < 5185 cells/mcL. For well-appearing infants with tactile fever only at home, there is less evidence to guide management. A 2017 meta-analysis found the sensitivity and specificity of caregivers? tactile assessment of fever to be 87.5% and 54.6%, respectively. While one option is to observe the infant in the ED with measurement of a rectal temperature, consideration should also be given to a sepsis workup, particularly in neonates…
You can read more on this subject by reviewing the issue: https://www.ebmedicine.net/topics/infectious-disease/febrile-young-infant
I agree with you answer about the tests. But I was wondering, would you not best hospitalize this child? The infant is only 40 days old and has a RSVirus infection, which makes the child prone to apnea?
I concur with the above.