Published: 2021-09-23

Thrombocytosis: a predictor of severity in children with lower respiratory tract infection

Chandrakala P., Vinutha Patil, Kavya V. N., Sushmitha .


Background: Community acquired pneumonia remains a significant cause of morbidity and mortality due to infection all over the world. Thrombocytes are known to be an essential part of immune response to various infectious agents. Platelet count elevated more than normal is often sign of severe pneumonia according to various studies.

Methods: This is a retrospective study conducted in Kempegowda Institute of Medical Science, a tertiary care hospital in Bangalore with a study duration of 1 year. All children were classified into two groups based on platelet count that is with thrombocytosis and without thrombocytosis. Respiratory distress was defined as presence of tachypnoea, chest retractions, oxygen saturation <94% in room air. Children with respiratory distress were classified as severe pneumonia and those with no respiratory distress as non-severe pneumonia.

Results: A total of 213 children were admitted with lower respiratory tract infection of which 35 children were excluded based on exclusion criteria. Of these 178 children 142 (80%) belonged to non-severe pneumonia group and 36 (20%) belonged to severe pneumonia group. Thrombocytosis is found in 31 (17%) children, 147 (82%) children had platelet count less than 4.5 lakhs/cu mm. Of these children with thrombocytosis 13 (42%) had non severe pneumonia and 18 (58%) had severe pneumonia. The p<0.0000001 which showed statistical significance, that is thrombocytosis was significantly associated with severity of pneumonia.

Conclusions: Thrombocytosis can be considered as a marker of severity of pneumonia in day-to-day practice.


Severe pneumonia, Non-severe pneumonia, Thrombocytosis, Respiratory distress

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