Back ground and objectives : Acute Respiratory Infections (ARI) are one of the most causes for evaluation and
management at pediatric outpatient clinics. Most common of these ARIs are self limiting viral illnesses but majority are
prescribed with antibiotics which is one of the major contributory factor for development of antibiotic resistance. So the aim of this study was to
determine the ideal combination of clinical signs and biomarkers measured in resource limited settings and to facilitate accurate diagnosis and
management and inturn antibiotic stewardship.
Methods: From June 2021 to Jan 2022, children between one month and 5 years of age presenting with fever and at least one respiratory
symptom to the OPD MIMS are included in the study. Patients with pneumonia and severe pneumonia basing on IMNCI guidelines and no
exclusion criteria were included in this study. Participants underwent total leukocyte count (WBC), Absolute neutrophil count (ANC), C -
reactive protein (CRP), procalcitonin (PCT), chest X-ray. A multiplex polymerase chain reaction (PCR), Sputum blood and urine cultures and
sputum microscopy was done to identify the pathogen. Demographic and clinical characteristics of the participants were recorded. We studied
the predictive accuracy by combining best clinical signs and biomarkers using statistical analysis.
Results: In 15% of cases there was evidence of a mixed viral/bacterial infection, viral infection alone was detected in 52% and bacterial
infection alone in 31% of patients. Children aged >2 years had a bacterial pneumonia more often than children aged <2 years. Among clinical
markers Respiratory rate and oxygen saturation (92%) could discriminate accurately between bacterial LRTI and other LRTI. The proportion of
patients with an increased WBC (>15.0 × 10^9/1) or increased ESR (>40 mm/h) was similar in bacterial and non bacterial RTI (48% v 47% and
66% v 60%, respectively). The differences in the CRP levels were signicant at the selected levels of >40 mg/l (p=0.005), >80 mg/l (p=0.001).
PCT > 0.25 μg/L showed the best discriminating ability (AUROC 0.92; 96% CI 0.88–0.98), followed by CRP > 80 (0.80; 0.72–0.88). The
combination of tacypnea and procalcitonin had the better predictive value (AUROC 0.98, 97% CI 0.94–1.00).
Conclusions: Strict adherence to national guidelines and training physicians in assessment of clinical signs will reduce antibiotic use but still
leads to over or under treatment. Although ideally point of care testing for respiratory pathogens like inuenza and RSV would be employed, this
is unlikely to be feasible at peripheral health centers and pediatric clinics in India in the near future. Therefore, it remains important to consider
use of Procalcitonin that can be quickly and easily adopted even less effective than rapid tests for pathogens.
