Dengue is a re-emerging mosquito-borne tropical infection that causes significant pediatric morbidity. The study aimed to evaluate the diagnostic utility of two simple hematologic indices—the neutrophil-lymphocyte ratio (NLR) and the platelet-lymphocyte ratio (PLR)—for identifying dengue and severity among children and adolescents presenting with fever. The authors note that while these ratios have been evaluated in adults across conditions such as sepsis and COVID-19, they are underutilized in pediatric practice due to limited evidence and awareness.
This was a cross-sectional study conducted in the Department of Paediatrics at a tertiary care centre in South India over a two-year period. The study population included children and adolescents aged 0–15 years who presented with fever and had dengue confirmed by serological testing. Blood samples for the analyses described were collected on day 3 of illness.
Complete blood count (CBC) samples obtained on illness day 3 were used to derive the NLR and PLR. The abstract reports that NLR and PLR values were calculated from standard CBC parameters, but the source does not provide the specific numeric cutoffs or thresholds used to define abnormal or severe values, nor does it detail the serologic tests employed or timing beyond the stated day 3 collection. The report focuses on the diagnostic performance characteristics of the two ratios.
Reported performance metrics from the study were:
The authors conclude that PLR demonstrated superiority in overall accuracy, specificity, and sensitivity for identifying severe dengue cases compared with NLR. However, they also report that NLR had a higher positive predictive value in this cohort. The abstract does not provide absolute numbers, confidence intervals, or details about prevalence, which are required to fully interpret predictive values and accuracy estimates.
NLR and PLR showed a strong positive correlation in this pediatric dengue cohort, with a correlation coefficient r = 0.83 and p < 0.001. This indicates that higher values of one ratio were strongly associated with higher values of the other in the samples analyzed.
Based on the reported metrics, the authors suggest that PLR may be a more effective simple hematologic marker than NLR for identifying severe dengue in children, given its higher sensitivity and specificity. The strong correlation between the two ratios implies they reflect related aspects of the host inflammatory and hematologic response to dengue infection. The study reinforces the potential clinical utility of CBC-derived indices as low-cost, widely available adjuncts to clinical assessment in resource-limited settings.
The abstract provides core findings but omits several important methodological and result details:
Because these details were not reported in the source abstract, they cannot be inferred; they would be necessary to fully assess generalizability, statistical robustness, and clinical applicability of the reported sensitivity/specificity and predictive values.
In this cross-sectional pediatric cohort from a tertiary centre in South India, calculated on day 3 of illness, platelet-lymphocyte ratio (PLR) outperformed neutrophil-lymphocyte ratio (NLR) in sensitivity and specificity for identifying severe dengue, while NLR demonstrated a higher positive predictive value. The two ratios were strongly correlated (r = 0.83, p < 0.001). The study highlights the promise of CBC-derived indices as inexpensive adjunctive markers in pediatric dengue but, based on the abstract alone, lacks sufficient detail on sample size, cutoffs, and severity definitions to enable full critical appraisal. Further published data or the full text would be required to clarify these points and to inform clinical implementation.