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Clinical features and diagnosis of bacterial sepsis in the preterm infant (<34 weeks gestation)

Leonard E Weisman, MD
Mohan Pammi, MD, PhD
Section Editors
Joseph A Garcia-Prats, MD
Morven S Edwards, MD
Deputy Editor
Carrie Armsby, MD, MPH


Neonatal sepsis remains a major cause of neonatal mortality and morbidity in preterm and very low birth weight (VLBW) infants [1-5]. As a result, clinical care providers should have a very low threshold for evaluation and treatment for possible sepsis in preterm and VLBW infants, as delays in diagnosis or treatment may worsen clinical outcomes.

The clinical features and diagnosis of bacterial sepsis in the preterm infant will be reviewed here. The management and prevention of bacterial sepsis in the preterm infant are discussed separately. (See "Treatment and prevention of bacterial sepsis in the preterm infant (<34 weeks gestation)".)

Systemic infections due to virus and fungi in the preterm infant, and sepsis in the term and late preterm infant are also discussed separately. (See "Nosocomial viral infections in the neonatal intensive care unit" and "Clinical manifestations and diagnosis of Candida infection in neonates" and "Clinical features, evaluation, and diagnosis of sepsis in term and late preterm infants" and "Management and outcome of sepsis in term and late preterm infants".)


The following terms will be used throughout this topic:

Preterm infants are those born at less than 34 weeks gestation.

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Literature review current through: Nov 2017. | This topic last updated: Feb 29, 2016.
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