Paeds · rheumatology-musculoskeletal-and-sports
Osteomyelitis and discitis
Also known as acute haematogenous osteomyelitis · AHO · paediatric bone infection · Kingella kingae osteomyelitis · spondylodiscitis · discitis · vertebral osteomyelitis in children · subperiosteal abscess
A fellowship approach to paediatric acute haematogenous osteomyelitis and discitis: the metaphyseal capillary bed where bacteria seed, the age-stratified microbiology dominated by Kingella kingae under four years and Staphylococcus aureus at all ages, magnetic resonance imaging as the diagnostic gold standard, and the evidence-based intravenous-to-oral antibiotic switch strategy that shortens hospital stays without compromising cure.
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Red flags
- A febrile child with focal bone tenderness and refusal to bear weight has osteomyelitis until proven otherwise — obtain blood cultures, inflammatory markers, and magnetic resonance imaging without delay
- Pseudoparalysis in an infant or a toxic, irritable child with an apparently painful limb may be the only sign of osteomyelitis or septic arthritis, because the pre-verbal child cannot localise the pain
- Discitis in a toddler who refuses to sit, crawl, or walk, or who holds the spine rigid, demands urgent magnetic resonance imaging — the window between reversible infection and permanent neurological injury is narrow
- A child who fails to improve within forty-eight to seventy-two hours of appropriate intravenous antibiotics has a subperiosteal or intraosseous abscess, a resistant organism, or an alternative diagnosis — escalate imaging and surgical review
- Kingella kingae osteomyelitis presents with a milder inflammatory response and often normal inflammatory markers, so a low threshold for blood culture and molecular testing is essential in children under four years
Life stages
Care settings
Clinical exam formats
Board mappings
- Infectious diseases - recognise and initiate management of acute haematogenous osteomyelitis in children
- Acute presentations - the febrile child with a painful limb and refusal to bear weight
- Musculoskeletal medicine - differentiate osteomyelitis from septic arthritis and transient synovitis
- Infectious diseases - interpret MRI findings and guide intravenous-to-oral antibiotic switch in paediatric osteomyelitis
- Musculoskeletal medicine - age-stratified microbiology including Kingella kingae in young children
- Renewed curriculum for first-year trainees from 2027 - Learning goal 6: Clinical management - essential general paediatrics
- Musculoskeletal 10-12
- Infectious diseases 10-12
- Acute presentations 10-12
- Short Cases
- Long Cases
- 8. Infection - bone and joint infection including osteomyelitis and discitis
- 2. Children presenting with musculoskeletal problems
- 4. Professional skills and knowledge: Patient management
- Foundation of Practice (FOP)
- Theory and Science (TAS)
- Applied Knowledge in Practice (AKP)
- Clinical
- History
- Communication
- Video
- General Pediatrics Content Outline - Infectious Diseases: osteomyelitis
- General Pediatrics Content Outline - Universal Task 3: Physical Examination
- General Pediatrics Content Outline - Universal Task 5: Patient Management
- Patient Care 4: Clinical Reasoning
- Patient Care 5: Patient Management
- Medical Knowledge 2: Diagnostic testing
- Pediatrics: Infectious diseases applied domain
- Pediatrics: Infectious diseases
- Pediatrics: Musculoskeletal infections applied domain
A two-year-old boy is brought in with three days of fever and a refusal to walk. He holds his left leg still and cries when you palpate the distal tibial metaphysis. His C-reactive protein is 85 milligrams per litre, his white cell count is 16,000, and his blood culture grows Kingella kingae on day three. The magnetic resonance image shows marrow oedema in the distal tibia with a small subperiosteal collection, and he improves within forty-eight hours of intravenous cefazolin. He switches to oral amoxicillin-clavulanate at day five, completes a four-week course, and recovers fully. A four-year-old girl refuses to sit and holds her back rigid, with an erythrocyte sedimentation rate of 60 — discitis until the magnetic resonance image reveals high signal in two adjacent vertebral bodies and the intervening disc. [1] [9]
Run the pathway as five moves. Suspect osteomyelitis in any febrile child with focal bone pain, pseudoparalysis, or refusal to bear weight, because the clinical suspicion is the single most important diagnostic step. Culture the blood before antibiotics, because a positive blood culture spares the child a bone biopsy and guides definitive therapy. Image with magnetic resonance imaging, because it is the gold standard and it reveals the subperiosteal abscess that demands surgery. Treat with empirical intravenous antibiotics that cover Staphylococcus aureus and Kingella kingae, because the right drug early saves bone. Switch to oral therapy when the child is afebrile, improving, and the C-reactive protein is falling, because the oral switch is safe, effective, and shortens the stay. [1] [3]
Overview & Definition
Acute haematogenous osteomyelitis is a bacterial infection of bone that reaches the skeleton through the bloodstream rather than by contiguous spread or direct inoculation. In children, it is the commonest form of bone infection, and it arises because the rich capillary network of the growing metaphysis creates a slow-flowing, low-oxygen environment in which bacteria can lodge and multiply. The haematogenous route distinguishes it from contiguous osteomyelitis, which follows trauma or surgery, and from the vascular-insufficiency pattern seen rarely in children. [2] [11]
The clinical syndrome is defined by the triad of fever, focal bone pain, and functional impairment. In the pre-verbal child, the pain manifests as pseudoparalysis — the child simply stops using the limb — and in the ambulant child, it manifests as a limp or a refusal to bear weight. The pain is typically well localised to the metaphysis of a long bone, most often the tibia or the femur, and it is constant, progressive, and unrelated to activity. The systemic features — fever, malaise, irritability — may precede the localising pain by a day or two, which is why the febrile child with an apparent limb problem is assessed with osteomyelitis in the differential from the outset. [2] [4]
Discitis, or spondylodiscitis, is the vertebral analogue of acute haematogenous osteomyelitis, and it affects the disc space and the adjacent vertebral bodies in children aged one to five years. The presentation is distinctive — a toddler who refuses to walk, sit, or crawl, holds the spine rigid, and may complain of abdominal or back pain — and the diagnosis is confirmed by magnetic resonance imaging. Discitis is often a milder, more self-limiting infection than long-bone osteomyelitis, but the potential for spinal cord compression and permanent neurological injury demands the same urgency of diagnosis and imaging. [9] [10]
References12ShowHide
- [1]Woods CR, Bradley JS, Chatterjee A, et al. Clinical Practice Guideline by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America: 2021 Guideline on Diagnosis and Management of Acute Hematogenous Osteomyelitis in Pediatrics. Journal of the Pediatric Infectious Diseases Society, 2021.PMID 34350458
- [2]Yeo A, Ramachandran M. Acute haematogenous osteomyelitis in children. BMJ (Clinical research ed.), 2014.PMID 24446020
- [3]Weichert S, Sharland M, Clarke NM, et al. Acute haematogenous osteomyelitis in children: is there any evidence for how long we should treat? Current Opinion in Infectious Diseases, 2008.PMID 18448970
- [4]Gornitzky AL, Kim AE, O'Donnell JM, et al. Diagnosis and Management of Osteomyelitis in Children: A Critical Analysis Review. JBJS Reviews, 2020.PMID 33006465
- [5]Restrepo R, Park HJ, Karakas SP, et al. Bacterial osteomyelitis in pediatric patients: a comprehensive review. Skeletal Radiology, 2024.PMID 38504031
- [6]Yagupsky P. Diagnosing Kingella kingae infections in infants and young children. Expert Review of Anti-infective Therapy, 2017.PMID 28918656
- [7]Wong M, Williams N, Cooper C. Systematic Review of Kingella kingae Musculoskeletal Infection in Children: Epidemiology, Impact and Management Strategies. Pediatric Health, Medicine and Therapeutics, 2020.PMID 32158303
- [8]Mitchell PD, Abraham A, Carpenter C, et al. Consensus guidelines on the management of musculoskeletal infection affecting children in the UK. The Bone and Joint Journal, 2023.PMID 37399098
- [9]Al Yazidi LS, Hameed H, Kesson A, et al. Spondylodiscitis in children. Journal of Paediatrics and Child Health, 2022.PMID 36000507
- [10]Ferri I, Ristori G, Lisi C, et al. Characteristics, Management and Outcomes of Spondylodiscitis in Children: A Systematic Review. Antibiotics (Basel), 2020.PMID 33396379
- [11]Arnold JC, Bradley JS. Osteoarticular Infections in Children. Infectious Disease Clinics of North America, 2015.PMID 26311358
- [12]de Graaf H, Sukhtankar P, Arch B, et al. Duration of intravenous antibiotic therapy for children with acute osteomyelitis or septic arthritis: a feasibility study. Health Technology Assessment, 2017.PMID 28862129