Foreign Body Infections

"Foreign Body" (Device) Infections Implanted Devices Vulnerable to Infection Indwelling Intravenous catheters Prosthetic cardiac valves Prosthetic orthopedic devices (joint replacements) Cerebrospinal fluid shunts/Ventriculostomy drains Peritoneal dialysis catheters Arterious-venous anastomoses (dialysis) Vascular grafts Mesh soft tissue support Silicon Implants (plastic surgery) Cardiac pacemakers CPT Coding Complication of an Internal Prosthesis, Implant or Graft--infection or Inflammation 996.60 Unspecified 996.61 Cardiac 996.62 Vascular 996.63 Nervous system 996.64 Urinary catheter (indwelling) 996.65 Genitourinary other 996.66 Joint prosthesis internal 996.67 Orthopedic other internal 996.69 Other Internal prosthesis

Intravascular Device Infections Types (Examples) Peripheral Short Lines (Angiocath) Peripheral Long Lines (Landmark) Percutaneous CVP (Cooke triple lumen) Pulmonary artery catheter (Swann-Ganz) Tunnel/Cuff (Broviac) Implanted Port (Port-a-Cath) Intravascular Device Infections Risk factors Cutdowns > Percutaneous Insertion Central lines > peripheral Femoral > Jugular • Subclavian Long duration • short duration (< 72 hours) Polyvinyl chloride • Teflon or silastic Direct insertion • tunneled Frequent access > Infrequent access Parenteral nutrition • noninitiative fluids • antibiotics Tegaderm • open air dressings Intravascular Device Infections Pathogenesis Contamination of Intradermal Insertion wound (+ bleeding) Formation of intravascular "fibrin sheath"

Colonization of catheter, formation of "bifilms" and "macrocolonies" Infection of "fibrin sheath" Release of "planktonic" organisms Local or generalized intravascular infection Intravascular Device Infections Common organisms Coagulase-negative staphylococci Staph. aureus (including MRSA) Candida albicans Klebsiella - Enterobacter Enterococci (now including VRE) Pseudomonas aeruginosa Intravascular Device Infections Unusual organisms Corynebacterium jeikeium Pseudomonas cepacia Serratia marcescens Acinetobacter calcoaceticus Torulopsis glabrata Malassezia furfur Candida lusitaniae Intravascular Device Infections Clinical Manifestations Occult bacteremia Exit site Infections "Tunnel" infections Sepsis/septic shock Septic thrombophlebitis - peripheral or central vein Metastatic spread - eyes, CNS, lungs operative sites, other prosthetic devices, heart Intravascular Device Infections Line Removal Pros Removes focus of infection Shortens duration of therapy Reduces chances of metastatic spread Cons Local/systemic antibiotics may cure Multiple lines/uncertain source Limited access Need for line may be time-limited Intravascular Device Infection Antibiotics Treat through all incriminated venous lines and lumens Synergistic/additive combinations Antibiotic "lock" technique (heparin/antibiotic compatibility) Don't use vancomycin unnecessarily Duration determined by response and presence of metastatic infection Intravascular Device Infections Prevention Block adhesion of organisms new polymers, detergents, disaccharides Prevent bacterial growth impregnated antibiotics, infused antibiotics, antibiotic "lock" technique Intravascular Device Infections

Diagnosis Criteria for "significant" bacteremia < 48 hours to positive result 2/2 bottles positive Repeated cultures positive Intravascular Device Infections Diagnosis Other culture criteria Semiquantitative cath tip pneltive Pus expressed from tunnel positive Persistent bacteremia despite appropriate Rx Higher level bacteremia from incriminated catheter Intravascular Device Infections Treatment options Line removal Antibiotics Both Strategy, sites of new lines Neurologic Device Infections Types of Devices (Examples) External ventricular drains (ventriculostomy) Subcutaneous access ports (Ommaya) Ventriculo-peritoneal shunts (Hakim) V-atrial, V-jugular, V-pleural Subarachnoid screws/bolts (El Camino) Neurologic Device Infections Epidemiology/Risk Factors Timing close to operation (<2 months) Overall rates 5-35% Thin cortex • thick cortex High protein > low protein Low pressure > high pressure July • rest of academic year Repeat surgery • initial surgery Head shaving night before • shave at operation Neurologic Device Infections Organisms Coagulase-negative Staphylococci Staph. aureus Corynebacterium sp. Propionibacterium acnes Enteric gram negative rods Candida sp.

Neurologic Device Infections Clinical Manifestations Shunt malfunction-headache, vomiting, irritability, mental status changes, coma Shunt reservoir doesn't "pump" properly Fever (not invariably present) Peritonitis (VP shunts) Bacteremia/sepsis/nephritis (V-A and V-J) Neurologic Device Infections Diagnosis

Ventricular fluid examination Plate as well as broth processing of culture CT scan or U/S (enlarging ventricles) Abdominal U/S ("CSFoma") Paracentesis (V-P shunt) Blood culture (V-A or V-J) Lumbar puncture (if meningitis) Neurologic Device Infection Treatment Device removal or externalization with or without ventriculostomy Systemic antibiotics (choice based on organisms and CSF penetration) _+ Systemic synergistic antibiotics (rifampin, TMP/SMX) +_ Intraventricular antibiotics (vancomycin) Duration: CSF sterilization + 7 - 21 days Continue through replacement operation

Neurologic Device Infections Prevention Operative site preparation Surgical technique Prophylactic antibiotics (methanolyses suggest benefit) Preoperative cultures "know your enemy" Perioperative systemic antibiotics Intraoperative ventricular antibiotics Peritoneal Dialysis Infections Epidemiology/Pathogenesis Incidence: I per 7 patient-months Prevalence: 60% of dialyzed patients Usual pathogenesis: skin colonizationexit site-tunnel-peritoneum Other mechanisms: Contamination of dialysate Suboptimal technique of hookup Mechanical bowel perforation Ascending infection from Fallopian tubes Peritoneal Dialysis Infections Organisms Coagulase-negative staphylococci Staph. aureus (including MRSA) Enteric gram negative rods Pseudomonads Enterococci (including VRE) Candida albicans Atypical mycobacteria

Peritoneal Dialysis Infections Clinical Manifestations/Diagnosis Fever, abdominal pain, cloudy dialysate Leukocyte count of dialysate >501ul No consensus on optimal culture method -broth inoculation of 1-5 ml sample --membrane filtration of larger volumes/plate Inoculation Consider frugal/mycobacterial cultures Peritoneal Dialysis Infections

Treatment Bolus instillation of antibiotics or mix with dialysate Systemic antibiotics at appropriate Intervals, with level monitoring Removal of catheter/short term hemodialysis If treatment failure. Usually necessary with fungal, pseudomonal, or enterococcal Infection Peritoneal Dialysis Infections Prevention Aseptic technique during insertion and manipulation Elimination of staph, aureus nasal and skin colonization (mupirocin, rifampin)

Orthopedic Device Infections Types of Devices (Examples) Operative fracture stabilization (screws, plates) External fixators (pins) Lengthening devices (11izarov) Prosthetic joints (limb salvage) Scoliosis repair (Luque rod) Orthopedic Device Infections Pathogenesis/Risk Factors Skin flora (elective surgery) Environmental flora (trauma) Reactivation (repeat/revision surgery) Airborne operating room transmission probably quite rare Orthopedic Device Infections Organisms/Sources Staph. aureus (including MRSA) Coagulase negative staphylococci Group A streptococci Enteric gram negative rods Pseudomonads Biopsy versus drainage cultures

Orthopedic Device Infections Clinical Manifestations/Diagnosis Fever, pain (not always present) Wound Infection, dehiscence, or fistula Radiographs (lucent, sclerotic areas or periosteal reaction) Hematologic/acute phase reactants Anemia of chronic disease Elevated or increasing ESR/CRP Leukocytosis, thrombocytosis Limitations of CT, MRI, and nuclear scans Orthopedic Device Infections Treatment Removal of device, hardware, and cement

(immediate or staged) Specific antimicrobial therapy Cidal drugs (;idactams) Bone accumulation (clindamycin) Antibiotic beads (tobramycin or vancomycin) Achieve control of infection with parenteral therapy Frequent monitoring (CBC, ESR) Orthopedic Device Infections Prevention Cultures ("know your enemy") Prophylactic/suppressive antibiotics