White Blood Cell Count Can Aid Judicious Antibiotic Prescribing in Acute Upper Respiratory Infections in Children

Abstract

Fifty percent or more of children with upper respiratory infections (URIs) and nonspecific febrile illnesses (e.g., children febrile, anorexic, decreased activity, irritable) receive unnecessary antibiotics from community-based physicians. This study was undertaken to show that white blood cell (WBC) count testing can aid physicians in avoiding antibiotic prescribing when managing children with URIs, and nonspecific febrile illnesses. A prospective, 3-year study was conducted in a community-based pediatric practice. A weekly convenience sample (Tuesdays) of acute URI and febrile patients ages 3 months to 21 years was studied. Data collected on enrollment included: age, gender, duration of illness, recent/current antibiotic use, temperature, symptoms, signs, laboratory testing (WBC count, cultures), diagnosis and treatment. Similar data on any illness visits in the previous 2 weeks and the subsequent 2 weeks after enrollment were collected. Viral culture specimens were obtained on a subset. The use of the WBC count was assessed, including obviating antibiotic prescription, frequency of related follow-up visits, and the occurrence of subsequent bacterial infections. Of 1,956 patients with respiratory or febrile illness enrolled, 1,219 (62%) had a diagnosis established by history and examination (e.g., acute otitis media) and 737 (38%) did not. Of the 737 patients without an established diagnosis, 386 (52%) did not receive an antibiotic because they did not appear particularly ill, their temperature was less than 101 degrees F, and parents were not demanding antibiotics, leaving 351 (48%) patients who appeared ill, had a temperature greater than 101 degrees F, and parents were demanding an antibiotic or physicians were inclined to give an antibiotic. A WBC count was performed on these 351 children; 337 children (96%) had a WBC count less than 15,000/mm3, and 14 (4%) had a WBC 15,000/mm3 or greater. An antibiotic was prescribed for 13 of the 14 children with a WBC count greater than 15,000/mms. With this approach, return office visits in the following 2 weeks were infrequent (13% of 737 patients), and no child had significant bacterial illness that was missed. With selective use of WBC count testing

Diagnostic Accuracy of FebriDx: A Rapid Test to Detect Immune Responses to Viral and Bacterial Upper Respiratory Infections

“…Therefore, we developed a reference standard algorithm that incorporated multiple individual tests with the aim of identifying bacterial infections with a host response and pathogenic viral infections ( Figure 1 ). Recognizing that all clinically-important bacterial URIs were unlikely to be detected by throat culture and NP/OP PCR, we classified culture- and PCR-negative patients as bacterial when elevated PCT and WBC levels suggested bacterial infection [ 18 , 19 , 20 , 21 , 22 ]. Given the strong association between NP/OP PCR detection of influenza, adenovirus, parainfluenza, RSV, human metapneumovirus and symptomatic disease, [ 12 , 13 , 14 ] identification of any of these viruses was considered a pathogenic infection in our algorithm.…”

“…The reference testing algorithm classified patients as having a bacterial infection if any of the following 5 criteria were met: (1) throat culture positive for a bacteria that commonly causes pharyngitis (Group A and C β-hemolytic Streptococci , N. gonorrhoeae , C. diphtheria , A. haemolyticum ) plus PCT ≥0.1 ng/mL; (2) throat culture positive for any other bacteria plus PCT ≥0.15 ng/mL; (3) NP/OP sample PCR positive for atypical bacteria ( M. pneumoniae , C. pneumoniae , B. pertussis ) plus PCT ≥0.1 ng/mL; (4) PCT ≥0.25 ng/mL plus no identified pathogen; (5) PCT ≥0.15 ng/mL plus WBC ≥15,000 cells/mcL or presence of WBC bands plus no identified pathogen [ 18 , 19 , 20 , 21 , 22 ]. Meanwhile, the reference testing algorithm classified patients as having a viral infection if any of the following 3 criteria were met: (1) NP/OP sample PCR positive for influenza A or B, adenovirus, respiratory syncytial virus (RSV), human metapneumovirus, or parainfluenza viruses 1–4; (2) NP/OP sample PCR positive for EBV plus serum IgM positive for EBV; (3) PCT between 0.15 ng/mL and 0.25 ng/mL plus WBC <15,000 cells/mcL plus no WBC bands plus no identified pathogen [ 21 ].…”

Predicting observation unit treatment failures in patients with skin and soft tissue infections

“…We believed a more moderate leukocytosis would be more predictive of severe disease. This value has been used in other studies to assist in estimating severity of disease [14–15]. Variables thought to be clinically related to disposition decisions from the OU or found to be relevant in prior research were first evaluated by a fitted model for univariate analysis.…”

A prospective, multi-centre US clinical trial to determine accuracy of FebriDx point-of-care testing for acute upper respiratory infections with and without a confirmed fever

“…0.15 ng/ml plus WBC ! 15,000 cells/mcL or the presence of WBC bands plus no identified pathogen [23][24][25][26][27]. Meanwhile, the reference testing algorithm classified patients as having a viral infection if any of the following four criteria were met: (1) NP/OP sample PCR positive for influenza A or B, adenovirus, respiratory syncytial virus (RSV), human metapneumovirus, or parainfluenza viruses 1-4; (2) NP/OP sample PCR positive for rhinovirus or coronavirus plus PCT !…”