CLINICAL PROBLEM SOLVING „Batteries not included” Antea Topić MD, PhD

History 60-y-old man was admitted to hospital with a 30-d history of fever (up to 39° C), weakness, occasional diarrhea and coughing medical history included PTSD and surgical treatment of a perforated duodenal ulcer 20 y ago a pacemaker was implanted because of extreme bradycardia and recurrent syncope 3 y ago an afunctional generator was removed pacemaker lead was left in situ; it perforated the skin 6 m earlier

Patient examination febrile (39.2° C), BP 100/65 mmHg, HR 92/min, respirations 18/min a painless wound with a perforating lead under the right clavicle was present (no surrounding erythema or tenderness) regular heart rhythm with a midsystolic murmur (2/6) left of the sternal border

Presumed clinical diagnosis pneumonia infectious diarrhea bacteraemia FUO endocarditis/lead infection More than one answer possible...

Correct answers: pneumonia infectious diarrhea bacteraemia FUO endocarditis/lead infection

Next step(s)? chest X-ray blood cultures ECG echocardiogram basic blood tests all of the above

Correct answer: chest X-ray blood cultures ECG echocardiogram basic blood tests all of the above

Diagnostic test results CRP – 149.5 mg/l tWBC count – 24.5×109/l with mature neutrophilia RBC count – 3.75×1012/l, haemoglobin – 112 g/l platelet count – 56×109/l

Diagnostic test results (continued) ECG – normal transthoracic echocardiogram – a mass (12 mm) attached to the pacemaker lead in the right ventricle heart valve function – normal Chest X-ray – abandoned pacemaker lead

Diagnostic test results (continued) 3 separate sets of blood cultures grew Staphylococcus lugdunensis susceptible to: penicillin, oxacillin, vancomycin, gentamicin, cipro-floxacin, rifampicin, azithromycin, clindamycin, linezolid, tigecycline, co-trimoxazole, and mu-pirocin the MICs were: penicillin 0.023 mg/l, oxacillin 0.25 mg/l, and vancomycin 0.5 mg/l

Staphylococcus lugdunensis is a Gram positive bacterium is a separate species of coagulase negative staphylococci (CoNS) is an important pathogen in the cardiovascular system infections infections tend to have a more fulminant course, resembling that of S. aureus rather than those caused by CoNS is a member of common skin flora all of the above

Correct answer: is a Gram positive bacterium is a separate species of coagulase negative staphylococci (CoNS) is an important pathogen in the cardiovascular system infections infections tend to have a more fulminant course, resembling that of S. aureus rather than those caused by CoNS is a member of common skin flora all of the above

S. lugdunensis was named after discovery in: Lyon (France) Lu’an (China) Lugano (Switzerland) Lug (Germany) Luxembourg (Luxembourg)

Correct answer: Lyon (France): its Latin name – Lugdunum Lu’an (China) Lugano (Switzerland) Lug (Germany) Luxembourg (Luxembourg)

Diagnosis is: S. lugdunensis endocarditis S. lugdunensis bacteraemia S. lugdunensis pacemaker lead infection S. lugdunensis blood contamination

Correct answer: S. lugdunensis endocarditis S. lugdunensis bacteraemia S. lugdunensis pacemaker lead infection S. lugdunensis blood contamination

Patient management: vancomycin gentamicin penicillin/oxacillin/flucloxacillin clindamycin lead extraction

Correct answers: vancomycin gentamicin penicillin/oxacillin/flucloxacillin clindamycin lead extraction

Pacemaker lead extraction Lead removal is warranted in following circumstances: TTE/TEE demonstrating valve or lead vegetation positive blood culture with S. aureus, CoNS, Propionibacterium sp., Candida sp. pocket infection high-grade bacteraemia due to an organism that commonly causes endocarditis, i.e. streptococci or enterococci transvenous extraction/surgical removal

Clinical course Treatment: flucloxacillin (2 g every 4 h i.v.) percutaneous lead extraction performed with no complications during 1-d monitoring microbiological analyses of the vegetation of the extracted pacemaker lead also yielded S. lugdunensis of same susceptibility six days after admission the patient started complaining of chest pain above the right costal margin

Clinical course (continued) Chest X-ray (supine) The presumed diagnosis: hospital pleuropneumonia haematothorax septic pulmonary embolism heart failure

Correct answer: hospital pleuropneumonia haematothorax septic pulmonary embolism heart failure Right-heart endocarditis can lead to septic pulmonary embolism (SPE). SPE has different imaging findings, such as nodules, patchy infiltrates, cavities, pleural effusions, gangrene, absceses and infarction.

Clinical course (continued) CT pulmonary angiography confirmed a presumed pulmonary embolism transthoracic echocardiogram – normal heart valve and systolic function, with mild tricuspid regurgitation because of persisting fever and recurrent S. lugdunensis bacteraemia – treatment modified; linezolid (600 mg bid) added to flucoloxacillin for the next 10 days therapeutic pleural puncture was performed

Clinical course (continued) defervescence occurred after 2 weeks the patient became afebrile with clinical and laboratory improvements surveillance blood cultures – negative patient finished 4 weeks of flucloxacillin therapy and has done well since discharge follow-up 1 m since discharge – uneventful

Summary Despite the clinical severity, the patient was managed successfully by an antimicrobial treatment. Pacemaker lead extraction was, most probably, crucial for his survival.