Estimate the incidence and pattern of reactive thrombocytosis among febrile young infants with serious bacterial infection


  • Rohit Chib Department of Pediatrics, Government Medical College Srinagar, Kashmir, India
  • Mohsin Rashid Department of Pediatrics, Government Medical College Srinagar, Kashmir, India
  • Surinder Kumar Department of Pediatrics, Government Medical College Srinagar, Kashmir, India



SBI, Platelets, Fever, Infant, Diagnosis


Background: Thrombocytosis or elevation in the peripheral blood platelet count to values >400,000/μL is common in infancy and childhood, occurring in 3 to 13% of children. The objective of study was to estimate the incidence and pattern of reactive thrombocytosis among febrile young infants with serious bacterial infections (SBIs).

Methods: The study was conducted in the Postgraduate Department of Pediatrics, G.B. Pant hospital, an associated hospital of Govt. Medical College Srinagar, which is a referral tertiary care hospital for the children of Kashmir valley. The study was a prospective non-randomized study conducted from April 2011 to March 2012. All infants of age 30-89 days admitted in hospital with rectal temperature >38C/100.4F without an apparent focus of infection on history and clinical examination were included in the study.

Results: The incidence of reactive thrombocytosis >4 lakh/mm3 in our study was 33 out of 39 (84.6%) in SBI versus 60 out of 110 (54.5%) in Non-SBI, which was statistically significant in SBI, p value < 0.05. Mean platelet count in urinary tract infections was 5.3 lakh/mm3, bacterial meningitis 5.2 lakh/mm3, occult bacteremia 4.9 lakh/mm3, pneumonia 4.7 lakh/mm3 and 3.9 lakh/mm3 across Non-SBI.

Conclusions: The incidence of reactive thrombocytosis >4 lakh/mm3 in our study was significantly higher in SBI (84.6%) than in Non-SBI (54.5%), p value < 0.05. Mean platelet count was highest in urinary tract infections followed by bacterial meningitis, occult bacteremia and pneumonia. So platelet count >4 lakh/mm3, reactive thrombocytosis, being simple and easy test to perform can be used for early prediction of SBI.


Sutor AH. Thrombocytosis in childhood. Semin Thromb Hemost. 1995;21:330-9.

Kaushansky K. Thrombopoietin: the primary regulator of platelet Production. Blood. 1995;86:419-31.

Papageorgiou T, Theodoridou A, Kourti M, Nikolaidou S, Athanassiadou F, Kaloutsi V. Childhood essential thrombocytosis. Pediatr Blood Cancer. 2006;47:970-1.

Dror Y, Zipursky A, Blanchette VS. Essential thrombocythemia in children. J Pediatr Hematol Oncol. 1999;21:356-63.

Dame C, Sutor AH. Primary and secondary thrombocytosis in Childhood. Br J Haematol. 2005;129:165-77.

Heng JT, Tan AM . Thrombocytosis in childhood. Singapore Med J. 1998;39:485-7.

Vora AJ, Lilleyman JS. Secondary thrombocytosis. Arch Dis Child. 1993;68:88-90.

Sandoval C. Thrombocytosis in children with iron deficiency anemia: series of 42 children. J Pediatr Hematol Oncol. 2002;24:593.

Yohannan MD, Higgy KE, al-Mashhadani SA, Santhosh-Kumar CR. Thrombocytosis Etiologic analysis of 663 patients. Clin Pediatr. 1994;33:340- 3.

Denton A, Davis P. Extreme thrombocytosis in admissions to paediatric intensive care: no requirement for treatment. Arch Dis Child. 2007;92:515-6.

Vlacha V, Feketea G. Thrombocytosis in pediatric patients is associated with severe lower respiratory tract inflammation. Arch Med Res. 2006;37:755-9.

Garoufi A, Voutsioti K, Tsapra H, Karpathios T, Zeis PM. Reactive thrombocytosis in children with upper urinary tract infections. Acta Paediat. 2001;90:448-9.

Robey C, Chmel H. Thrombocytosis associated with acute osteomyelitis. Infection. 1984;12:384-6.

Baraff LJ, Oslund SA, Schriger DL, Stephen ML. Probability of bacterial infections in febrile infants less than three months of age: a metaanalysis. Pediatr Infect Dis J. 1992;11:257-64.

Hsiao AL, Chen L, Baker MD. Incidence and predictors of serious bacterial infection among 57 to180-day-old infants. Pediatrics. 2006;117:1695-701.

Baker MD, Avner JR, Bell LM. Failure of infant observation scales in detecting serious illness infebrile, 4- to 8- week-old infants. Pediatrics. 1990;85:1040-3.

Ishimine P. Fever without source in Children 0 to36 months of age. Pediatr Clin North Am. 2006;53:167-94.

Fouozas S, Mantagou L, Skylogianni E, Varvarigou. Reactive Thrombocytosis in Febrile Young Infants with Serious Bacterial Infection From the Department of Pediatrics, University Hospital of Patras, Patras, Greece.Indian Pediatr. 2010;47:937-43.

Consensus Statement on Management of Urinary Tract Infections. Indain Pediatrics. 2001;38:1106-15.

Nelson Textbook of Pediatrics. 1996;2;603:2936-48.

Craig JC, Williams GJ, Jones M. The accuracy of clinical symptoms and signs for the diagnosis of serious bacterial infection in young febrile children: prospective cohort study of 15 781 febrile illnesses BMJ. 2010;340:c1594.

Galetto-Lacour A, Zamora SA, Gervaix A. Bedside procalcitonin and C-reactive protein tests in children with fever without localizing signs of infection seen in a referral center. Pediatrics. 2003;112;1054-60.

Pulliam PN, Attia MW, Cronan KM. C-reactive protein in febrile children 1 to 36 months of age with clinically undetectable serious bacterial infection. Pediatrics. 2001;108;1275-9.






Original Research Articles