OSTEOMYELITISOSTEOMYELITIS INFECTIOUS ARTHRITISINFECTIOUS ARTHRITIS

D.GoldbergD.GoldbergWRAMCWRAMC

OsteomyelitisOsteomyelitis

Laboratory TestsLaboratory Tests

White blood cell countWhite blood cell countErythrocyte sedimentation rateErythrocyte sedimentation rateC-reactive proteinC-reactive proteinBone aspirateBone aspirateBlood cultureBlood cultureAntigen AssayAntigen Assay

OsteomyelitisOsteomyelitis Etiologic agents by ageEtiologic agents by age

Organism Total <2 2-5 6-10 >10Organism Total <2 2-5 6-10 >10

S. aureus 198 (50%) 33 56 66 43Streptococci 37 (9%) 13 13 6 5HIb 16 (4%) 14 2 0 0CNS 10 (3%) 7 1 0 2Ps. aeruginosa 10 (3%) 1 2 5 2S. pneumoniae 6 (2%) 6 0 0 0Salmonella 6 (2%) 3 3 0 0E. coli 2 1 1 0 0

Osteomyelitis

Specimen siteSpecimen site No. done No. done No. Pos No. Pos

BloodBlood 381 138 (36%) 381 138 (36%)Needle aspirate/surg specNeedle aspirate/surg spec 357 134 (38%) 357 134 (38%)Joint fluidJoint fluid 86 56 (65%) 86 56 (65%)Wound drainageWound drainage 31 22 (70% 31 22 (70%))

Nelson IDCNA 1995

OsteomyelitisOsteomyelitis

BONE MONOSTEAL POLYSTEALFemur 92 12Tibia 89 18Humerus 50 8Fibula 16 10Phalanx 18 5Calcaneos 18 0Radius 13 4Ischium 15 1Metatarsal 8 0Ulna 6 3Ilium 7 0Vertebra 7 2

Osteomyelitis

Neonatal Osteomyelitis

Indolent processNonspecific signs absentSwelling/tendernessMultiple sites in 50%Secondary joint space involvementS. aureus, group B strep, coliforms

Osteomyelitis

Sickle Cell Disease

Salmonella 60%GNR’s 6%Staphylococcus 8%Pneumococcus 5%

Radiologic Diagnosis

X-rays: soft tissue swellingperiosteal elevationfocal osteopenia2 week lag

Tc scan: accumulation in areas ofinc blood flow and boneformationpositive in 48 hrsThree-phase scanfalse-neg due to poorblood flow

Radiologic Diagnosis

Radiologic Diagnosis

gallium scan: inc uptake in areasof PMN’s, macrophagesdo not show bone wellimaging at 24h and 72hhigh sens/high radiation

MRI scan: bone vs soft tissueT2-inc signal in bonenot for screening

Septic Arthritis

Volume +/+++ +/+++ +Color turbid turbid sl turbidViscosity reduced reduced normalWBC’s >50-100 5-50 1-5PMN’s >80% >60-80% <50%Glucose <0.25 >0.50 >0.80Bacteria 50-75% 0 0

S.A. Inf Arth Non-IA

Septic ArthritisSeptic Arthritis

Distribution of Infected Joints

Knee 30%Hip 30Ankle 17Elbow 11PIP/MCP 7Shoulder 2

Nelson PED 1972

Septic ArthritisSeptic Arthritis

Organism 0-1m 1m-5y >5 (4%) (70%) (26%)

S. aureus 36% 11% 33%Hib 7% 31% 1%Streptococci 21% 11% 18%GNR 14% 2% 3%N. gonnorrhea 7% 2% 7%Unknown 35% 34%

Therapy

Initial regimes:

Neonates nafcillin and cefotaxime children < 5 cefuroxime children > 5 nafcillin/cefuroxime Sickle cell nafcillin and ceftriaxone

Therapy:

Minimal duration- (clinical response, dec ESR)

Gram negative 4-6 weeksStaph 4-6 weeksH. influenzae 2-4 weeksN. meningitis 2-4 weeksstreptococci 2-4 weeks

Dagan JPID 1992

Contraindications to oral therapy

Inability to swallowInability to swallowEtiologic agent not establishedEtiologic agent not establishedInability to perform bacteriocidal Inability to perform bacteriocidal

levelslevelsNo effective oral therapyNo effective oral therapyFailure of parental abioticsFailure of parental abiotics