Silent infective endocarditis with mucocutaneous stigmata, and delay in initiating echocardiography

Infective endocarditis (IE) without murmurs (silent IE) is an entity fraught with the risk of missed diagnosis. This hazard is attributable to a suboptimal index of suspicion for IE, and, hence, suboptimal workup for IE, when a murmur is absent. This state of affairs was exemplified by anecdotal reports of 15 adult patients (11 male) of mean age 48 years who were characterised by the association of silent IE and mucocutaneous stigmata of IE (table 1),^1–15 and in whom echocardiography was initiated after a delay of one day to seven months (median seven days) following documentation of mucocutaneous stigmata. None had ‘same day’ echocardiography. In addition to mucocutaneous stigmata, nine of the 15 patients also had risk factors for IE, namely, dental caries,^9,10,12,15 ear piercing,¹¹ post-operative wound infection,³ intravenous drug use,¹³ and cirrhosis of the liver.^2,6 Three patients had an afebrile presentation.^2,12,13 Echocardiography disclosed vegetations in 13 patients.^{1–4,6–8,10–15} Eight patients (including four with risk factors for endocarditis) subsequently developed new murmurs.^{1,2,5,6,9,12,14,15} In five of those cases echocardiography was undertaken after detection of the murmur.^1,2,9,14,15

Table 1. Clinical features and complications.

First author	Symptoms/complications	Pur	Jn	Spl	SCH	Os	Valve	Culprit pathogen
Cecarelli1	Meningitis, SMA, SE	Y	N	N	N	N	Mitral	Staph. aureus
Deonarine2	Cirrhosis, CHF, spondylitis	Y	N	N	N	N	Quadrivalve	Strep. mutans
El Chami3	CHF, respiratory failure	Y	N	N	N	N	Aortic	Enterococcus faecalis
Yokota4	Mesenteric abscess	Y	N	N	N	N	Mitral	MSSA
Miridjanian5	Fever, myalgia, headache	Y	N	Y	Y	N	Aortic	Moraxella kingae
Mahmoud6	Cirrhosis, CHF, ICE	Y	N	N	N	N	Mitral	Pasteurella multocida
Tiliakes7	Polyarthralgia, ANCA+ve, splenomegaly	Y	N	N	N	N	Aortic	Strep. viridans
Messiaen8	CHF, Gln, ANCA+ve	Y	N	N	N	N	Aortic	Few bacterial colonies
Chukwurah9	Gln, ICE	Y	N	Y	N	N	Aortic	Lactobacillus, Acidophilus
Branch10	ICE	N	Y	N	Y	Y	Mitral	Pasteurella multocida
Nah11	ICE, meningitis, CHF, SE, RE	N	Y	Y	Y	N	Mitral	MRSA
Nichols12	ICE	N	Y	N	N	Y	Mitral	Strep. viridans
Yeung13	ICE, CHF, SMA, SE	N	N	Y	Y	N	Aortic	Serratin marcescens
Ching14	ICE	N	N	N	N	Y	Aortic	MSSA
Inoue15	CHF, spondylitis, septic arthritis	N	N	N	N	Y	Aortic	MSSA

Key: ANCA+ve = positive for anti-neutrophilic cytoplasmic antibodies; CHF = congestive heart failure; Gln = glomerulonephritis; ICE = intracranial embolism; Jn = Janeway lesions; MRSA = methicillin-resistant Staphylococcus aureus; MSSA = methicillin-sensitive Staphylococcus aureus; N = No; Os = Ostler’s nodules; Pur = purpura; RE = renal embolism; SCH = subconjunctival haemorrhages; SE = splenic embolism; SMA = skeletal muscle abscess; Spl = splinter haemorrhages; Y = Yes

Complications comprised intracranial embolism (ICE, seven cases), congestive heart failure (seven cases), meningitis (two cases), spondylitis (two cases), skeletal muscle abscess (two cases), septic arthritis (one case), mesenteric abscess (one case), splenic embolism (two cases), splenic embolism in association with renal embolism (one case), acute glomerulonephritis (two cases).

Treatment

Valve replacement was undertaken in seven cases,^{3,8–11,13,15} including three with torrential left ventricular failure attributable to valve cusp perforation.^3,8,11 One patient had mitral valvuloplasty.¹² Seven patients (including two deaths, both with congestive heart failure and cirrhosis),^2,6 were managed conservatively.

Comment

Among 54 IE patients with mucocutaneous stigmata, Servy et al. identified 18 with no murmurs. Intracranial embolism and extracranial embolism, respectively, were prevalent in 32.8% and 51.7% of patients. Immunological phenomena were significantly more common in IE patients with mucocutaneous stigmata than in counterparts without those stigmata.¹⁶ The present review takes the characterisation of silent IE further by documenting the cognitive bias that hinders timely investigation of this syndrome.

Funding Statement

Funding None.