Is Procalcitonin Useful in Early Diagnosis of Serious Bacterial Infections in Children ?

Address for correspondence Dr. Rakesh Gupta Professor & Head Department of Paediatrics Command Hospital (CC) Lucknow-226002 India E-mail: colrgupta@gmail.com How to cite this article ? Gupta R, Singh V, Patrikar S, Hazra N, Mathai SS. Is Procalcitonin Useful in Early Diagnosis of Serious Bacterial Infections in Children? J Nepal Paediatr Soc 2013;33(2):106-109. Is Procalcitonin Useful in Early Diagnosis of Serious Bacterial Infections in Children?


Introduction
D iagnosis of bacterial infections remains one of the greatest and most tantalizing challenges in medical science, especially in children, in whom clinical signs are often nonspecifi c and confusing and hence laboratory parameters become crucial 1,2 .The currently used markers for diagnosis of sepsis in children are not very specifi c. Marshall et al published a thorough report from the fi fth Toronto sepsis round table on measures, markers and mediators of clinical sepsis and suggested that many circulating or cell-associated molecules have been found to be useful markers for the presence, severity, or response to therapy of sepsis 3 .In recent years, several newer markers of infection have been investigated, such as procalcitonin (PCT) and interleukins (IL-6 and IL-8), which are easy to perform and in combination have high sensitivity and specifi city 4-8.The aim of this study was to evaluate procalcitonin as early marker of serious bacterial infection in children.

Results
Total 130 patients were considered for the study, of which 30 patients excluded as they did not fulfi ll the inclusion criteria.Maximum numbers of cases were in the age group of one month to one year (37%) with mean age of 27 months and male:female ratio of 1.5: 1. Maximum numbers of cases had involvement of respiratory system (54%) followed by gastrointestinal (20%), genitourinary (10%) and central nervous system (5%).Clinical profi le of the study population is depicted in Figure 1 and 2.

Discussion
Early diagnosis of the severe infections and the prompt initiation of adequate antimicrobial therapy are essential for the good outcome in infants and young children 1 .Chiesa et al reported that an abnormal PCT concentration in early neonatal sepsis with a sensitivity of 92% and specifi city of 97.5% 9 .These fi ndings were in agreement with our study, which showed the sensitivity and the specifi city of PCT to be 85% and 88% respectively.Suprin E et al compared PCT and CRP in ICU patients and found that PCT had better specifi city and sensitivity (93% and 94%) than CRP (75% and 73%) 10 .Among the organisms isolated from the blood, staph aureus was the commonest isolated organism seen in 55% whereas in a study by Jose R gram negative organisms were found in maximum number of cases 11 .
Our study demonstrated that newer markers namely PCT and IL8 were more sensitive than CRP, TLC and band counts for predicting sepsis in children.Similarly specifi city of these newer markers were higher that of CRP and band forms.Muller and colleagues investigated 101 patients admitted to medical ICU and found that PCT is a more reliable marker of sepsis than CRP, IL-6 and lactate levels 12 .A systematic review was published in 2004 investigating the value of PCT as a marker of bacterial infection in children and adults.Two of the 12 studies analyzed involved children, one of which had enrolled newborn infants, both demonstrated that PCT was more accurate marker than CRP for differentiating between viral and bacterial infections 13,14 .When combination markers PCT and IL8 were used by Carcello et al, sensitivity and specifi city increased to 94% and 90%.In our study the sensitivity increased to 90% and the specifi city 73% 4 .The future lies in demonstrating whether assaying PCT improves the prognosis of patients, by making early diagnosis possible and aiding with monitoring treatment.

Conclusion
Procalcitonin is a useful marker for in diagnosis of serious bacterial infections in neonates and children.Alone or in combination with IL8 it has a higher sensitivity and specifi city as compared to standard markers like CRP.Therefore it is recommended that procalcitonin should be used for the screening of sepsis in neonates and children so that the treatment can be started earlier in order to prevent morbidity and mortality.

Fig 2 :Fig 1 :
Fig 2: Showing the Clinical profi le of sepsis in study population This diagnostic evaluation study was carried out at a tertiary care hospital from Sep 2008 till Sep 2010, among newborns and children up to fi ve years of age presenting with features suggestive of systemic infl ammatory response syndrome (SIRS).

Table 1 :
Sepsis in the study population : Nil Funding: Armed Forces Medical Research committee fund Confl ict of interests: None stated Permission from IRB: Yes

Table 2 :
Sensitivity and specifi city of single and combination markers of infection

Table 3 :
Comparison of sensitivity and specifi city of markers of sepsis