Neonatal septic arthritis: Indian perspective

1. z
Neonatal septic arthritis
series:
The Indian scenario
Speaker: Dr ARNAB NANDY
Second year post-graduate trainee ( MD Pediatrics )
North Bengal Medical College and Hospital
Sushrutanagar, Darjeeling
Moderator: Dr RAKESH MONDAL
Professor, Department of Pediatrics
North Bengal Medical College and Hospital
Sushrutanagar, Darjeeling
29/09/2018

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INTRODUCTION
 Septic arthritis: Inflammation of synovial membrane of a joint
with purulent effusion into the joint capsule due to suppurative
joint infection.
 Incidence: 0.6/1000 live birth (India)
0.3/1000 live birth (Western countries)
 Classified under deep seated infection according to the location.
 Subtle and widely varied clinical presentation.
 Early detection and prompt management prevents life
threatening and morbid sequels.

3. Conflict prevails over few of the following facts about neonatal septic
arthritis –
 Frequency and site of joint involvement
 Time of onset of illness
 Disease correlation with gestational age, birth weight and co-morbid
conditions
 Diagnostic guideline
 Management protocol
 Prognostic factors and outcome

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PATHOPHYSIOLOGY
 Route of joint infection: - Primary
- Secondary (M/C)
 Secondary hematogenous seeding of infective organism more
common than direct inoculation or extension from contiguous focus.
 Why synovial space of joint is most vulnerable for seeding inciting
organism?
> Rich vascular supply
> Lacks a basement membrane
 Often in neonates, septic arthritis and osteomyelitis occurs in
conjunction or follows each other:
> Blood capillaries perforate epiphyseal plate in neonates
making communication between metaphysis and joint space.
Creating ideal setting for
hematogenous spread
into the joint

5. Seeding of infective organism into the joint space
↓
Release different toxins with in the joint space
(Ex. – bacterial endotoxin, exotoxins, hyaluronidase)
↓
Trigger inflammatory cascade by stimulating production of various cytokines
from tissue macrophages
(Tumor necrosis factor α, interleukin 1)
↓
Chemotaxis of neutrophils into the joint space
↓
Release proteolytic enzymes, elastase and accumulation of exudative
inflammatory fluid in the afflicted joint
↓
Degradation of articular cartilage with combination of the following
- Direct damage caused by inflammatory enzymes
- Compromised vascular supply due to accumulated inflammatory fluid in
the closed joint space and induce pressure necrosis due to increased intra-
articular pressure
↓
Intra-capsular synovial proliferation preceded by initial joint inflammation and
stretching of joint capsule by accumulated inflammatory fluid
↓
Joint deformity, laxity, dislocation, contracture of the afflicted joint
Algorithm 1 :
Pathophysiology of
neonatal septic
arthritis

6. z
Clinical features
 Difficult to elicit specific sign and symptoms pertaining to septic
arthritis in neonate.
 Vague constitutional symptoms and reduced movement of the
affected limb are the most adherent presentation in such
situation.
 Lack of well-defined manifestation
– Early diagnosis can often be missed even in
experienced hands.
 High degree of clinical suspicion helps for early detection in
such scenarios.

7. Systemic presentation:
 Lethargy
 Irritability
 Refusal to suck
 Inconsolable cry
 Hyper/hypo-thermia
Joint presentation:
 Reduced movement of the affected
limb (Pseudo-paralysis)
 Cry immediately on handling the
involved limb
 Abnormal posture
 Swelling of the afflicted joint
 Erythema of overlying skin of the
involved joint
 Increased temperature of the affected
joint
Often subtle and vague
Manifestation of joint
inflammation

8. z
Clinical profile

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Predisposing factors
 Prematurity
 Low-birth weight
 Intra-uterine infection (Example – syphilis, TORCH infection etc.)
 Peri-partum genital tract infection of mother
 Difficult labour (Example – cephalo-pelvic disproportion, PROM)
 Congenital anomalies
 Co-morbid conditions like neonatal sepsis, birth asphyxia,
meconium aspiration, congenital heart disease, severe neonatal
jaundice etc.
 Post-natal interventions in the form of intra-venous lines,
umbilical catheterisation, mechanical ventilation etc.

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Causative organisms
 Klebsiella spp.
(M/C in India)
 Staphylococcus aureus
(M/C worldwide)
 Group B streptococci
 Other staphylococcus spp.
like Staph. epidermidis,
Staph. hominis, coagulase
negative staphylococci etc.
 Escherichia coli
 Proteus spp.
 Hemophilus influnzae
 Pseudomonas spp.
 Salmonella spp.
 Gonococci
 Enterobacter spp.
 Candida spp.

11. z
Diagnosis
 Clinical suspicion gets priority over laboratory investigations for
early detection.
 Diagnostic approach:
- Ante-natal and peri-natal history
- Clinical examination
- Blood and radiologic investigations
- Joint fluid analysis

12. Important specific history to be elicited:
 Any ante-natal infections
 Untoward Peri-natal events
 History of genital tract infection of mother
 Any intervention required after birth / relevant post-natal events
 Elaboration of present illness
- Presenting illness
- Time of onset
- Duration
- Progression of illness
- Treatment received (if any)
 Search for predisposing factors
Ex. – Birth weight, gestational age at birth, co-morbidities
etc.
Clinical evaluation for physical signs:

13. Blood parameters evaluation :
 Complete blood count
 Blood culture and sensitivity testing (Mandatory)
 Inflammatory markers like C-reactive protein (CRP), erythrocyte sedimentation
rate (ESR).
Radiologic evaluation :
(a) Plain roentgenographic finding –
→ Widened joint space
→ Obliteration of normal fat lines
→ Widened arc with elevated shenton’s line
→ Loss of white cortical line (marginal erosion)
→ Dislocation or narrowing of joint space (in later stage)

14. Plain
roentgenographic
film of bilateral hip
& knee joint
depicting septic
arthritic features in
right sided hip
joint of a neonate -

15. (b) Ultrasonographic finding –
→ Joint effusion
→ Echogenic debris
→ Fluid collection in soft tissue and sub-periosteal region
→ Lateral displacement and dislocation
(c) Computed tomographic(CT) scan and Magnetic resonance imaging(MRI) scan –
 CT scan delineates extent of bone involvement well
 MRI depicts
→ Enhancement of inflamed areas with in the afflicted joint (on T1 image)
→ Synovial thickening
→ Extent of cartilage damage
→ Tracking of surrounding soft tissue oedema and abscess
→ Adjacent bone information
(d) Radionuclide imaging scan with technetium 99 –
Helps in pointing focus of infection at the earliest with increased uptake
in the affected part of bone.

16. Joint fluid evaluation (Ultrasound guided aspiration of synovial fluid) :
→ Physical character
Turbid and less viscous
→ Microscopic examination
Increased cell counts ( > 50,000/µL)
Predominantly polymorphs (PMN)
→ Biochemical examination
Increased protein
Decreased glucose
→ Gram staining
→ Culture and sensitivity testing
→ Synovial fluid biomarker
Collagen Ⅱ degradation products, Cartilage oligomeric matrix protein (COMP)
Correlation with severity of cartilage damage and joint inflammation

17. Lee SC, Shim JS, Seo SW, Lee SS. Prognostic factors of septic arthritis of hip in infants
and neonates: minimum 5-year follow-up. Clinics in orthopedic surgery. 2015 ;7:110-9.
Diagnostic criteria for neonatal septic arthritis:

18. z
Differential diagnosis
 Transient synovitis
 Pyomyositis
 Toxic synovitis
 Osteomyelitis
 Cellulitis
 Abscess in adjacent tissue
 Collagen vascular disease
 Neonatal lupus arthritis
 Rheumatoid arthritis
 Miscellaneous

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Case series profile

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Comparative analysis

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Management

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Complications
Joint complication
 Avascular necrosis
 Premature closure of physeal
growth plate
 Pseudarthrosis
 Chondrolysis
 Dislocation of joint
 Joint contracture
Systemic complication
 Neonatal sepsis
 Neonatal meningitis
 Osteomyelitis
 Urinary tract infection
 Subcutaneous abscess
 Failure to thrive
 Miscellaneous

24. z Prognosis
 Early detection and appropriate treatment results into excellent outcome.
Factors influencing overall outcome –
 Birth weight
 Prematurity
 Time elapsed between onset of illness and contact with medical facility
 Co-morbidities like neonatal sepsis, birth asphyxia etc.
 Number and site of afflicted joint
 Pre-intervention radiological changes
 Concomitant bone pathologies like osteomyelitis, congenital anomalies
 Mechanical ventilation
 Nature of surgical intervention - guided needle aspiration, arthrotomy.
 Restriction of movement at discharge

25. Year of
study
n =
sample
of follow-
up
Mean
period of
follow-up
Satisfact
ory
outcome*
Unsatisfa
ctory
outcome*
Death
Chul Lee
S et. al.
2015 31 cases 5 years 26 5 0
Usha
Devi et.
al.
2016 52 cases 15
months
26 26 0
Kabak S
et. al.
2002 14 cases 4.2 years 12 1 1
Li Y et. al. 2016 48 joints
(44
cases)
4.5 years 35 13 N/A
* Outcome described on the basis of any residual limitation of joint movement,
any persistent sequels and radiological changes.
Overall outcome of septic arthritis in different studies:

26. Outcome of neonatal septic arthritis for different joints involved:
Li Y, Zhou Q, Liu Y, Chen W, Li J, Yuan Z, Yong B, Xu H. Delayed treatment of
septic arthritis in the neonate: A review of 52 cases. Medicine. 2016 ;95:1-5.

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Complications

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References