Paeds · infectious-diseases
Bacteraemia and occult bloodstream infection
Also known as Bloodstream infection · Occult bacteraemia · Positive blood culture · Invasive bacterial infection · Fever without source · Serious bacterial infection
An age-, appearance- and immunity-aware fellowship approach to bacteraemia and occult bloodstream infection in children: how viable bacteria in the blood present from the febrile young infant through the older child, how to risk-stratify and investigate, how to resuscitate the septic child, when to give empiric antibiotics, and how conjugate vaccines have reshaped the whole question.
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Target exams
Red flags
- Toxic or shocked appearance, prolonged capillary refill, mottled or cold peripheries
- Petechial or purpuric rash progressing rapidly — treat as meningococcaemia until proven otherwise
- Fever with altered mental state, bulging fontanelle, abnormal tone or seizures
- Neonate or young infant with temperature instability, feeding difficulty, grunting, apnoea or irritability
- Immunocompromise, neutropenia, central venous catheter or functional asplenia with fever
- Child who deteriorates or fails to improve after initial assessment while a blood culture is pending
- Caregiver report that the child is different from their usual self, or repeated representation
Life stages
Care settings
Clinical exam formats
Board mappings
- General Paediatrics
- Recognise, investigate and manage bloodstream infection and the febrile child at risk of invasive bacterial infection
- Apply age-stratified febrile infant pathways, empiric antimicrobial therapy and antimicrobial stewardship
- Clinical Applications
- Medical Sciences
- Long Cases
- Short Cases
- 4. Professional skills and knowledge: Patient management
- 7. Patient safety, including safe prescribing
- Infection, Immunology and Rheumatology: recognises and manages serious invasive infection
- Paediatric Intensive Care: recognises the deteriorating child
- Applied Knowledge in Practice (AKP)
- Foundation of Practice (FOP)
- Theory and Science (TAS)
- History
- Communication
- Video
- General Pediatrics Content Outline — Infectious Diseases
- General Pediatrics Content Outline — Emergency and Critical Care
- General Pediatrics Content Outline — Universal Task 3: Diagnosis
- General Pediatrics Content Outline — Universal Task 4: Management and Treatment
- Patient Care 4: Clinical Reasoning
- Patient Care 5: Patient Management
- Systems-Based Practice 1: Patient Safety
- Medical Knowledge: Diagnostic testing and antimicrobial selection
- Medical Expert
- Pediatrics: Foundations EPA 1 — Recognizing deteriorating and/or critically ill patients and initiating stabilization and management
Overview & Definition
Picture a 14-month-old brought in with two days of fever to 39.5 °C. She is alert, smiling, drinks from her cup, has a clear chest, no rash and no obvious focus. In the pre-pneumococcal-vaccine era, between roughly three and nine of every hundred children just like her had bacteria circulating in their bloodstream, and the worry was that pneumococcus might settle in her meninges before anyone realised. Today that number is a fraction of one per cent. The child has not changed; the population risk has. That shift is the single most important idea on this topic. [1] [9]
Bacteraemia is the presence of viable bacteria in the bloodstream, confirmed when a blood culture grows a pathogen. The word describes a laboratory and physiological fact, not a syndrome. A febrile child with bacteraemia may be in septic shock, may have an obvious pneumonia, or may look completely well — the same finding spans the whole spectrum of severity. [1] [12]
Occult bacteraemia is the historical name for the child at the well end of that spectrum: fever without an apparent focus in a child who does not look toxic, where bacteraemia is found only because a blood culture was drawn. It was a clinical problem worth chasing in the 1990s because occult pneumococcal bacteraemia carried a real risk of meningitis if the child was sent home untreated. With pneumococcal and Haemophilus influenzae type b conjugate vaccines, the prevalence fell so far that the question reframed: clinicians now ask whether the febrile child is at risk of a serious or invasive bacterial infection, and use validated pathways to decide who needs investigation and empiric treatment. [1] [3] [9]
Why the modern numbers reframe the question
References13ShowHide
- [1]Gomez B Bacteremia in previously healthy children in emergency departments: clinical and microbiological characteristics and outcome European journal of clinical microbiology & infectious diseases, 2015.PMID 25252630
- [2]Kuppermann N A Clinical Prediction Rule to Identify Febrile Infants 60 Days and Younger at Low Risk for Serious Bacterial Infections JAMA pediatrics, 2019.PMID 30776077
- [3]Pantell RH Evaluation and Management of Well-Appearing Febrile Infants 8 to 60 Days Old Pediatrics, 2021.PMID 34281996
- [4]Mahajan P Risk of Bacterial Coinfections in Febrile Infants 60 Days Old and Younger with Documented Viral Infections The Journal of pediatrics, 2018.PMID 30195552
- [5]Mahajan P Association of RNA Biosignatures With Bacterial Infections in Febrile Infants Aged 60 Days or Younger JAMA, 2016.PMID 27552618
- [6]Kanegaye JT Lumbar puncture in pediatric bacterial meningitis: defining the time interval for recovery of cerebrospinal fluid pathogens after parenteral antibiotic pretreatment Pediatrics, 2001.PMID 11694698
- [7]Bachur R Reevaluation of outpatients with Streptococcus pneumoniae bacteremia Pediatrics, 2000.PMID 10699100
- [8]Korones DN Occult pneumococcal bacteremia: what happens to the child who appears well at reevaluation? The Pediatric infectious disease journal, 1994.PMID 8072821
- [9]Ben-Shimol S Dynamics of invasive pneumococcal disease in infants younger than 2 years old following PCV7/13 implementation using two infant and a booster dose schedule: evidence for indirect protection of young infants, Israel, 2004 to 2019 Euro surveillance, 2023.PMID 37347413
- [10]Gaur AH Optimizing blood culture practices in pediatric immunocompromised patients: evaluation of media types and blood culture volume The Pediatric infectious disease journal, 2003.PMID 12799512
- [11]Norman-Bruce H Diagnostic test accuracy of procalcitonin and C-reactive protein for predicting invasive and serious bacterial infections in young febrile infants: a systematic review and meta-analysis The Lancet Child & adolescent health, 2024.PMID 38499017
- [12]Weiss SL Surviving Sepsis Campaign International Guidelines for the Management of Sepsis and Septic Shock in Children 2026 Pediatric critical care medicine, 2026.PMID 41869844
- [13]Whelan SO Pediatric blood cultures - turning up the volume: a before and after intervention study European journal of pediatrics, 2024.PMID 38656384