Fellow: Maria Santos MD| Hospital Medicine Fellow | Children’s Hospital Los Angeles, University of Southern California, Keck School of Medicine
Article: Young, B. R., Nguyen, T. H., Alabaster, A., & Greenhow, T. L. (2018). The Prevalence of Bacterial Meningitis in Febrile Infants 29–60 Days With Positive Urinalysis. Hospital Pediatrics, 8(8), 450-457.
Summary: This retrospective cohort study identified 833 febrile infants 29 to 60 days old presenting to Kaiser Permanente Northern California sites (KPNC) from 2007 to 2015 who underwent evaluation (urinalysis, blood culture, urine culture and CSF cultures) to establish prevalence of meningitis among infants with positive versus negative urinalysis using a two 1-sided test for equivalence. Three of 337 infants with positive urinalysis (0.9%) and 5 of 498 infants with negative urinalysis (1%) had meningitis. These proportions were statistically equivalent and thus infants had a similar rate of meningitis regardless of whether they had a positive or negative urinalysis. A secondary exploratory aim was focused on identifying febrile infants 29-60 days old with presumed urinary tract infection that were treated with antibiotics (parenteral or oral) without a CSF culture in order to evaluate for adverse sequelae. Three hundred and forty-one infants were identified and there were no cases of missed bacterial meningitis or severe sequelae (including sepsis, seizure, neurological deficit, intubation, PICU admission or death) identified within one month following presentation.
What are the key strengths of the article?
This was a large-scale study of 833 infants which achieved similar rates of meningitis as the general population and as demonstrated in other studies (~1%). Additionally, the study did not exclude infants based on comorbid medical conditions (prematurity, technology dependence etc) making these results applicable across children’s hospitals. Given that KPNC is a closed healthcare system and has previously shown a 92.4% rate of retention for patients in the first 90 days of life, chances are low that many patients presented outside the Kaiser healthcare system and were lost to follow up. This study is supported by other related studies that have demonstrated infants with bacteremic UTI are at low risk for bacterial meningitis. Additionally, it was the first study of its kind to evaluate infants with presumed UTI who had received antibiotics and did not have CSF obtained for adverse outcomes.
Are there any limitations or flaws in the article?
By performing a retrospective chart review, there are inherent flaws such as losing patients to follow up at a separate hospital or biases from chart abstraction. As Kaiser is a closed healthcare system, the risk of losing patients to follow up is low. Additionally, the authors attempted to standardize key words present within the chart during data abstraction to minimize bias. Lastly, while novel, the exploratory aim was flawed in that it included both infants who had received either a parenteral dose of antibiotics or prescription for oral antibiotics. It could be argued that these are not equivalent treatments and are better evaluated separately. Furthermore there was no power analysis performed as this was an exploratory aim.
What is the major takeaway message?
The prevalence of bacterial meningitis does not differ among infants 29-60 days old based on a positive or negative urinalysis result.
Describe how this article should impact our practice:
Despite a positive urinalysis being labeled a risk factor in traditional risk stratification criteria (i.e Boston, Philadelphia, Rochester) there is evidence to suggest that this is not a specific risk factor for meningitis. These traditional risk stratification criteria all recommend a full sepsis work up for infants with a positive urinalysis. This study however has shown that infants 29-60 days old have the same rate of meningitis regardless of urinalysis results. While these risk stratification criteria are highly sensitive, they lack specificity as they were created in the 1980’s and early 1990’s when the rates of meningitis were much higher than they are at present. The prevalence of meningitis is at an all-time low and calls for a new set of risk stratification tools to identify infants at risk for meningitis while minimizing unnecessary interventions such as lumbar punctures, antibiotics and hospital admissions. Until more studies can be performed, a positive or negative urinalysis should not be used as the sole determinant for performing a full sepsis evaluation on a febrile infant 29-60 days old.
Article: Young, B. R., Nguyen, T. H., Alabaster, A., & Greenhow, T. L. (2018). The Prevalence of Bacterial Meningitis in Febrile Infants 29–60 Days With Positive Urinalysis. Hospital Pediatrics, 8(8), 450-457.
Summary: This retrospective cohort study identified 833 febrile infants 29 to 60 days old presenting to Kaiser Permanente Northern California sites (KPNC) from 2007 to 2015 who underwent evaluation (urinalysis, blood culture, urine culture and CSF cultures) to establish prevalence of meningitis among infants with positive versus negative urinalysis using a two 1-sided test for equivalence. Three of 337 infants with positive urinalysis (0.9%) and 5 of 498 infants with negative urinalysis (1%) had meningitis. These proportions were statistically equivalent and thus infants had a similar rate of meningitis regardless of whether they had a positive or negative urinalysis. A secondary exploratory aim was focused on identifying febrile infants 29-60 days old with presumed urinary tract infection that were treated with antibiotics (parenteral or oral) without a CSF culture in order to evaluate for adverse sequelae. Three hundred and forty-one infants were identified and there were no cases of missed bacterial meningitis or severe sequelae (including sepsis, seizure, neurological deficit, intubation, PICU admission or death) identified within one month following presentation.
What are the key strengths of the article?
This was a large-scale study of 833 infants which achieved similar rates of meningitis as the general population and as demonstrated in other studies (~1%). Additionally, the study did not exclude infants based on comorbid medical conditions (prematurity, technology dependence etc) making these results applicable across children’s hospitals. Given that KPNC is a closed healthcare system and has previously shown a 92.4% rate of retention for patients in the first 90 days of life, chances are low that many patients presented outside the Kaiser healthcare system and were lost to follow up. This study is supported by other related studies that have demonstrated infants with bacteremic UTI are at low risk for bacterial meningitis. Additionally, it was the first study of its kind to evaluate infants with presumed UTI who had received antibiotics and did not have CSF obtained for adverse outcomes.
Are there any limitations or flaws in the article?
By performing a retrospective chart review, there are inherent flaws such as losing patients to follow up at a separate hospital or biases from chart abstraction. As Kaiser is a closed healthcare system, the risk of losing patients to follow up is low. Additionally, the authors attempted to standardize key words present within the chart during data abstraction to minimize bias. Lastly, while novel, the exploratory aim was flawed in that it included both infants who had received either a parenteral dose of antibiotics or prescription for oral antibiotics. It could be argued that these are not equivalent treatments and are better evaluated separately. Furthermore there was no power analysis performed as this was an exploratory aim.
What is the major takeaway message?
The prevalence of bacterial meningitis does not differ among infants 29-60 days old based on a positive or negative urinalysis result.
Describe how this article should impact our practice:
Despite a positive urinalysis being labeled a risk factor in traditional risk stratification criteria (i.e Boston, Philadelphia, Rochester) there is evidence to suggest that this is not a specific risk factor for meningitis. These traditional risk stratification criteria all recommend a full sepsis work up for infants with a positive urinalysis. This study however has shown that infants 29-60 days old have the same rate of meningitis regardless of urinalysis results. While these risk stratification criteria are highly sensitive, they lack specificity as they were created in the 1980’s and early 1990’s when the rates of meningitis were much higher than they are at present. The prevalence of meningitis is at an all-time low and calls for a new set of risk stratification tools to identify infants at risk for meningitis while minimizing unnecessary interventions such as lumbar punctures, antibiotics and hospital admissions. Until more studies can be performed, a positive or negative urinalysis should not be used as the sole determinant for performing a full sepsis evaluation on a febrile infant 29-60 days old.