Bloodstream Infections and Infective Endocarditis — DCE Clinical Case

The systematic routine

End of the bed first. Look before touching: fever chart and observations at the foot, oxygen or monitoring, visible distress, cachexia from weeks of illness, and the clues to source and severity — intravenous lines, a PICC, a dialysis catheter, track marks suggesting injecting drug use [2].

Hands — the highest-yield peripheral examination. Splinter haemorrhages under the nails, Janeway lesions (non-tender macules on palms and thenar eminences), Osler nodes (tender nodules in the finger pulp), clubbing, and peripheral perfusion — a cold pulseless finger here is an embolus, and that is a vascular Duke criterion [1] [2].

Arms and access sites. Dialysis fistulae, old and new puncture sites, PICC or central line sites with any erythema — each is a potential portal of entry and changes the organism list [2].

Face, eyes and mouth. Conjunctival pallor and petechiae; then say the words — "I would examine the fundi for Roth spots" (retinal haemorrhages with pale centres). Inspect the teeth and gums: the dental state is both a source and a prevention conversation, and palatal petechiae count [1] [2].

The precordium. Inspect for a median sternotomy scar, a CIED pocket (and any erythema over it), then palpate and auscultate systematically. You are listening for regurgitant murmurs: the early diastolic murmur of aortic regurgitation at the left sternal edge in expiration, and the pansystolic murmur of mitral regurgitation at the apex radiating to the axilla — and for the mechanical clicks of a prosthetic valve. A new regurgitant murmur is itself a major Duke criterion [1].

Complete the circuit. Sacral and peripheral oedema and auscultated lung bases for heart failure (the surgical urgency), abdominal palpation for splenomegaly, a urine dipstick for haematuria (glomerulonephritis — an immunologic criterion), and a quick neurological screen for embolic deficits [1] [2].

Close the loop. "To complete my assessment I would review the temperature chart, the blood culture results and the echocardiogram" [3].

Presentation template (deliver this to the examiner)

"Mrs Wheeler is a 52-year-old woman with a bicuspid aortic valve and a three-week febrile illness. On examination she has peripheral stigmata of infective endocarditis — splinter haemorrhages and a tender Osler node — poor dentition, a new early diastolic murmur consistent with aortic regurgitation, and splenomegaly. These findings give her a major Duke criterion on the new murmur plus minor criteria of fever, predisposition, and vascular and immunologic phenomena. My next steps are three sets of blood cultures from separate sites before any antibiotic dose, transthoracic then transoesophageal echocardiography, and an endocarditis-team assessment" [1] [3].

Discussion — what the examiner will push on

"Which findings are vascular and which are immunologic?" — "Vascular phenomena are embolic: arterial emboli, Janeway lesions, conjunctival haemorrhage, mycotic aneurysm, intracranial haemorrhage, septic pulmonary infarcts. Immunologic phenomena are immune-complex mediated: glomerulonephritis, Osler nodes, Roth spots and a positive rheumatoid factor. Janeway is vascular; Osler and Roth are immunologic — that pair is the classic confusion" [1].

"Your cultures come back growing viridans streptococci in two sets. What now?" — "She now has two major criteria and definite endocarditis. I would stage with TOE, start organism-directed therapy — benzylpenicillin or ceftriaxone for a fully susceptible streptococcus, four weeks from the first negative culture — and assess her against the three surgical triggers: heart failure, uncontrolled infection, and embolism prevention" [2] [4].

"What would make you call the surgeons tonight?" — "Heart failure from acute severe regurgitation — that is the one that cannot wait for the antibiotic course. Uncontrolled infection — an abscess, persistent bacteraemia — and embolism prevention with a large vegetation after an embolic event follow close behind" [4].

"Why three sets of cultures, and why before antibiotics?" — "Because yield rises with set number and volume, the multi-set pattern separates continuous endovascular bacteraemia from contamination, and every antibiotic dose before cultures erodes the diagnostic yield I will rely on for the next month" [3].