ANA Testing Carrie Marshall 1/18/08

Septic Arthritis RRC R heumatology R esearch C enter

Infectious Arthritis SepticGonococcalViralFungalTuberculousLyme

Definition Acute joint infection due to bacterial agents Acute joint infection due to bacterial agents Medical emergency Medical emergency

Epidemiology Incidence: Incidence: 40-68/100000/ yr in Prosthetic joint 40-68/100000/ yr in Prosthetic joint 28-38/ / yr in RA 28-38/ / yr in RA 5- 12/ / yr in Children 5- 12/ / yr in Children 2-5/ / yr in GP 2-5/ / yr in GP

In Adult: 75% with risk factor In Adult: 75% with risk factor

Risk factors: Risk factors: Systemic: Systemic: Old age (>80 Y) Old age (>80 Y) RA RA DM DM Immunosuppressive Immunosuppressive Hemodyalisis Hemodyalisis Malignancy Malignancy Local: Local: RA RA OA OA Prosthetic joint Prosthetic joint

Etiology (microbiology) Microbial agent: Microbial agent: Staphylococcus aureus: most common (75-80%) Staphylococcus aureus: most common (75-80%) Other organism in special patients: Other organism in special patients: Sexually active woman: Neisseria gonorrheae Sexually active woman: Neisseria gonorrheae Elderly, IV drug abuser, immunocompromised, UTI: Gram negative (p. aeruginosa and E.coli) Elderly, IV drug abuser, immunocompromised, UTI: Gram negative (p. aeruginosa and E.coli) SLE: Salmonella SLE: Salmonella HIV: Pneumococci, Salmonella, H. influenzae HIV: Pneumococci, Salmonella, H. influenzae Alcoholism, Humeral immunity abnormality, Hemoglobinopathies: Pneumococcal infections Alcoholism, Humeral immunity abnormality, Hemoglobinopathies: Pneumococcal infections Primary immunoglobolin deficiency: Mycoplasma Primary immunoglobolin deficiency: Mycoplasma

Root of infection: Root of infection: Blood stream Blood stream Contiguous infection Contiguous infection Direct inoculation: Direct inoculation: Injection: Injection: Arthroscopic surgery: < Arthroscopic surgery: < Animal or human bite Animal or human bite

Site of involvement: Site of involvement: Mono (80-90%) Mono (80-90%) Knee: 55% Knee: 55% Ankle: 10% Ankle: 10% Wrist: 9% Wrist: 9% Shoulder: 7% Shoulder: 7% Hip: 5% Hip: 5% Elbow: 5% Elbow: 5% SC: 5%- IV drug abuser SC: 5%- IV drug abuser SI: 2%- IV drug abuser SI: 2%- IV drug abuser Foot joints: 2% Foot joints: 2% Poly (more than 1 joint): RA Poly (more than 1 joint): RA

SYNOVIAL FLUID SYNOVIUM Cartilage

Pathogenesis Microbial Factors: virulence Microbial Factors: virulence Host Factors: Immune response Host Factors: Immune response

Fibronectin binding protein Collagen Bindidng protein Protein A Coagulase Enterotoxin B TSST-1 alfa Toxin

Immune response: Immune response: Synovial cell: Synovial cell: IL1- IL6 (influx of immune cell) IL1- IL6 (influx of immune cell) Immune cells: Immune cells: Early cytokines: Clearance of organism Early cytokines: Clearance of organism Late cytokines: may amplify the destruction Late cytokines: may amplify the destruction

SYNOVIUM

Clinical manifestations Fever (toxic) Fever (toxic) Acute Acute Sever pain Sever pain Sever swelling of one joint Sever swelling of one joint Sever tenderness Sever tenderness Warmth Warmth Sever effusion Sever effusion Sever limited ROM Sever limited ROM

Acute Monoarthritis Sepsis workup Biochemist Synovial Fluid Aspiration (rule) Diagnosis

Acute Monoarthritis Synovial Fluid Aspiration Light microscope Smear- Culture Sepsis workup Biochemist

Acute Monoarthritis Synovial Fluid Aspiration Light microscope Smear- Culture Turbid - Purulent Leukocyte> 50,000/ml (> 90% PMN) Damaged WBC Crystal (-) Sepsis workup Biochemist

Acute Monoarthritis Synovial Fluid Aspiration Light microscope Smear- Culture Positive Gram stain: 75% in s. aureus 30-50% in gram (-) Positive Fluid culture: 90% PCR: partially treated or culture negative Sepsis workup Biochemist

Acute Monoarthritis Synovial Fluid Aspiration Light microscope Smear- Culture Positive Gram stain: 75% in s. aureus 30-50% in gram (-) Positive Fluid culture: 90% PCR: partially treated or culture negative Positive B/C : 50-70% Leukocytosis ESR & CRP Sepsis workup Biochemist

Radiography Early: Early: Soft tissue swelling Joint space widening Soft tissue swelling Joint space widening Predisposing agent Predisposing agent Late (2-3 w): Late (2-3 w): Erosion Erosion Joint space narrowing Joint space narrowing

AntibioticJoint Drainage TREATMENT

AntibioticJoint Drainage TREATMENT Empiric (IV): Smear Age or Risk factors Extra articular site

Empirical antibiotic Gram stain result: Gram stain result: Gram positive cocci: Gram positive cocci: Oxacillin or Naficillin (2g /q 4h) Oxacillin or Naficillin (2g /q 4h) Vancomycin (1g /q 12h) if methycillin-resistant S. aureus Vancomycin (1g /q 12h) if methycillin-resistant S. aureus Gram Negative: Gram Negative: Ampicillin or Cephalosporin Ampicillin or Cephalosporin No organism: No organism: In healthy, sexually active: Cefotaxime or ceftriaxone In healthy, sexually active: Cefotaxime or ceftriaxone In elderly debilitated patients: antistaphylococcal + Aminoglycoside + antipseudomonal penicillin or a third generation cephalosporin In elderly debilitated patients: antistaphylococcal + Aminoglycoside + antipseudomonal penicillin or a third generation cephalosporin

AntibioticJoint Drainage TREATMENT Empiric (IV): Smear Age or Risk factors Extra articular site Definitive therapy; based on culture

Definitive therapy S. aureous: 4 weeks Oxacillin Naficillin Vancomycin Pneumococal and streptococcal inf : 2 weeks Penicillin G, 2mU /q 4h H. influenzae and s. pneumoniae resistant to penicillin: 2 weeks Cefotaxime or Ceftriaxone Enteric gram negative: 3-4 w Second or Third Gen cephalosporin Fluoroquinolone (levofloxacin 500mg IV or Po every 24h) P. aeruginosa: 4 weeks Combination of AG + mezlocillin or ceftazidime (IV) 2 weeks Ciprofloxacin 750mg twice daily (oral) 2 weeks

AntibioticJoint Drainage Empiric (IV): Smear Age or Risk factors Extra articular site Closed needle Aspiration Arthrotomy: Hip, Shoulder TREATMENT Definitive therapy; based on culture

AntibioticJoint Drainage Closed needle Aspiration Arthroscopic Drainage: Symptom S. fluid volume S. fluid WBC S. fluid smear & culture Arthrotomy: Hip, Shoulder TREATMENT Empiric (IV): Smear Age or Risk factors Extra articular site Definitive therapy; based on culture

AntibioticJoint Drainage TREATMENT Frequent passive motion Until removal of inflammation signs No weight bearing