Andrea Guyot Consultant Microbiologist Educational Workshops 2013 Bone and Joint Infections UTI and prosthetic joint infections Andrea Guyot Consultant Microbiologist

77 y female patient: May 2011 L TKR insertion 1995 right TKR 3.5.2011 left TKR ASA3, BMI 33, MRSA neg comorbidities: Leg ulcers on shins with recurrent cellulitis Recurrent UTIs (last UTI in April 2011 on pre-assessment with fully sensitive E. coli) Chronic anaemia (Hb 10, iron 7)

What are known risk factors for prosthetic joint infections?

20.11.2011 Admission for vertigo Diagnosis of benign paroxymal positional vertigo treated with cinnarizine Urine: 1450 WBC (culture isolates identified by MaldiTOF): Klebsiella res amoxicilin only plus Enterobacter aerogenes res: Augmentin, cefalexin sens: cipro, trimethroprim, gentamicin, meropenem, cefpodoxime Blood: iron deficiency anaemia with iron 3 umol/l and transferrin 2.26g/l Platelets 320, WBC 9.9, Hb 8.9, CRP 49

Home discharge Discharge home on trimethroprim (to be taken until 26.11.2011) On 13.12.2011 readmission for swollen hot L TKR WBC 10, CRP 203, ESR 21, Hb 7.5, platelets 23 MSU: 94 WBC; Enterobacter aerogenes res: Augmentin, cefalexin sens: cipro, gent, cefpodoxime, trimethroprim

13.12.2011 Synovial fluid 3720 WBC, 73% PMN Citrobacter koseri (identified by MaldiTOF) res: Augmentin, cefuroxime sens: cipro, gent , cefpodoxime

What are the sensitivities of investigations on synovial fluid?

Risk of UTI for PJI Maderazo E et al Risk of UTI for PJI Maderazo E et al. Late infections of total joint prosthesis. Clin. Orthop Relat Res 1988;229:131-142 Incidence of PJI=1% Risk for haematogenous seeding 1:5= 0.2% Risk for seeding from UTI = 13% of 0.2%=0.026%= 26:100000 = approximately 1:4000 arthroplasties get infected by haematogenous seeding from UTI

15.12.2011 1st stage of revision Removal of TKR and implantation of Vancogenx spacer with Palacos R&G (gentamicin) cement on prophylactic dose of teicoplanin 600mg and 120mg gentamicin Meropenem 1g tds started postop 5 periprosthetic tissues grow Citrobacter kosei sens: meropenem, gentamicin, ciprofloxacin

How many periprosthetic tissues are required for DIAGNOSIS of PJI and what is the performance?

Which antibiotic would you choose for citrobacter?

16.12.2011 post-op Platelets 13, Hb 5.6, prothrombin time 15 sec, PT ratio 1.3 Haematological diagnosis: Thrombotic thrombocytopenic purpura Transferred to a specialist hospital for Rituximab and plasma exchange The features in the blood tests just prior to Christmas 2011 are absolutely classic with clear evidence of haemolysis, a grossly raised LDH of 1545 iu/L and no discernible ADAMS TS13 evident in her peripheral bloods. The low platelet count was because of the inability of the enzyme ADAMS TS13 to cut von Willebrand’s factor off her endothelial cells and therefore platelets were deposited in the vessel as a consequence. The most important thing in a patient like this is that you do not receive a platelet transfusion, which has been associated with fatal thrombotic stroke. Fortunately she was transferred to the specialist hospital for plasmaphoresis with FFP, which acts as a source of the missing enzyme ADAMS TS13 and also Rituximab therapy to destroy the B lymphocytes which produce the antibody in the first place.

25.1.2012 Return from specialist hospital on meropenem 1g tds: MRSA in nose, not in groin Mupirocin and chlorhexidine washes prescribed CRP 7.8, WBC 8, HB 10.5, platelets 300 going home on 26.1. on oral ciprofloxacin 750mg bd until 10.3.2012

How long should antibiotics be given between 2 stages of revision?

26.4.2012 Preassessment: MRSA neg, CRP 4, ESR 6, WBC 3.4, platelets 240, Hb 12.4 MSU 64 WBC, no growth

2.5.2012 2nd stage revision arthroplasty on flucloxacillin and gentamicin Joint fluid and tissues on enrichment culture: no growth

Follow up Discharge home 21.5.2012 ESR 21, CRP 5.4, WBC 3.4, platelets 208 Platelets 360, Hb 10.9 Follow up on 12.3.2013 (at 10 months after 2nd stage) No sinus formation CRP <4, ESR 16, WBC 5.7, Hb 11.9 Oxford score 22 (max=50, good revision outcome >30) with pain score 1 (=mild) ROM 120 C with lateral ligament laxity Xray: no loosening