Risk Factors Corticosteroids Existing arthritis Articular infection Infection elsewhere DM Trauma None

Frequency of Joints Knee Hip Ankle Elbow Wrist Shoulder Sternoclavicular

Pathology High vascularity S. aureus collagen-binding adhesin associated with osteomylitis but not septic joint Disruption of normal joint by pre-existing joint disease Proteolytic enzymes released

Signs and Symptoms Joint pain, swelling, warmth, and decreased range of motion Joint tenderness to pressure or movement Tendon tenderness Fever May resemble acute crystal dz. or hemothrosis

Organisms Associated Neisseria-1-12% Non-gonorrhea-S. aureus-37-56%, Streptococcal-10-28%, GNR-4-19%, coagulase negative staph-5%, anaerobic-2%, PMB-less than 10% Am Rheum Disease-2002, 61:267

Septic Arthritis-odd organisms Lyme, Mycoplasma Listeria, enterococcus, chlmydia M. tuberculosis, atypical Tb Candida, sporothrix, blastomycosis, coccidiom\ Rubella, hep b and c, EBV, parvovirus, mumps

Synovial Effusion Normal-clear, viscous, colorless-<200 wbc (<25% pmns) Noninflammatory-clear, viscous, yellow wbc-<25% pmns Inflammatory-cloudy, watery, yellow ,000 cells (>50% polys)

Synovial Effusion, continued Infected-purulent->50,000 cells (>75% pmns) Great overlap at times

Gonococcal vs. non gc Arthritis Gc-sexually active adults, migratory polyarthralgias, tenosynovitis, dermatitis common, >50% polyarthritis, BC positive <10%, joint fluid positive 25%

GC vs. non GC Non GC-very young or elderly, polyarthralgias, tenosynovitis rare, dermatitis rare, >85% monoarthritis, BC positive 50%, joint fluid positive 85-90% NEJM-1985, 312:

Outcome of Bacterial Arthritis 154, 121 adults-half had joint disease 29% of joints contained synthetic material Poor outcome in 21% of patients Poor joint outcome in nearly 50% of patients

Outcome continued Risk factors for poor outcome include- older age, existing joint disease, synthetic joint Arthritis and Rheumatism 1997, 40:884.

Factors Associated with Poor Prognosis Age >60 years Pre-existing rheumatoid arthritis or hip or shoulder infection >1 week of infection >4 joints involved Positive cultures after 7 days of appropriate treatment

Management Antimicrobials do achieve adequate levels in joint fluid Joint effusion drainage necessary but best method to drain is uncertain

Prosthetic Hip Infxns, Organisms Gram positive-CNSE>S. aureus>streptococcus>enterocc Gram negative-Enteric>pseudomonas Anaerobes least common J Bone Jt. Surg-1996, 78:512

Results of Rx of Infxns- Prosthetic Hip Positive intraoperative-28/31 good outcome (90%) 3.5 year followup Early Postoperative 25/35 (71% good outcome) 3.3 yrs followup Late chronic-29/34 (85%) good outcome-2.6 years followup

Results of Treatment continued Acute hematogenous-3/6 (50%) good outcome-2.6 years followup Journal Bone and Joint Surgery 1996, 78:512

Prosthetic Joint Infection Positive intraoperative cx-6 weeks iv with no surgical Rx Early (one month)-surgical, remove lines, leave bone components, 4 weeks iv antibiotics

Prosthetic Joint Infection Late chronic infection-debridement, remove components and cement, 6 weeks iv antibiotics Acute hematogenous-treatment same as early postoperative, replace components if loose J Bone Jt Surg 1995, 77: 1576

Rifampin Containing Regimens Proven S. aureus or coagulase negative staph infxns. Stable joint with sms less than 21 days Initial debridement and 2 weeks of antistaph followed by oral for 3 months if hip or 6 months if hip

Rifampin Containing Regimens 12/12 cured with cipro+rifampin 7/12 cured with cipro plus placebo JAMA-1998, 279, 1537 Lancet 2001, 1:175.

Suppression with oral In one study of patients who were high risk/poor function if joint removed- treatment mean was 37.6 months 10/13 patients required prothesis removal for recurrent infections (mean 21.6 months

Suppression-continued Conclusion-benefits are limited Orthopaedics-1991, 14:841.

Osteomyelitis classification Cierny and Mader-Orthopaedic Review- 1987, 16:259 I-medullary, II-superficial, III-localized, IV-diffuse Host factors-A-normal, B-compromised, C-prohibitive Waldvogel-NEJM-1970, 282:198 Hematogenous, continguous

Osteomyelitis diagnosis Staging studies-MRI, CT, nuclear scans, ESR, CRP, bone biopsies and cultures

Osteomyelitis treatment Surgery and antibiotics Controversies in length of treatment, etc.

Diabetic Foot MRI-99% sensitive, 83% specific Plain x-ray-60% sensitive, 66% specific Tc99m bone scan-86% sensitive, 45% specific In111 WBC-89% sensitive, 78% specific, CID 1997: 25: 1318

Probing to Bone Technique to determine bone infection Sterile, steel probe used positive test if bone can be touched with probe Sensitivity-89%, specificity-85% JAMA :721

Diabetic Foot 254 isolates from 96 patients S. aureus-38 isolates, Enterococcus-31, peptostreptococcus-31, CNSE-27, streptococcus sp-27, proteus-10, klebsiella-10 CID-1995, 20 (supplement 2).