Mycobacterial endocarditis: a comprehensive review

The data source of the present study was based on a comprehensive literature search in MEDLINE, Highwire Press and Google search engine for publications on mycobacterial endocarditis published between 2000 and 2013.

Results:

The rapidly growing mycobacteria become the predominant pathogens with Mycobacterium chelonae being the most common. This condition has changed significantly in terms of epidemiology since the 21^st century, with more broad patient age range, longer latency, prevailed mitral valve infections and better prognosis.

Conclusion:

Mycobacterial endocarditis is rare and the causative pathogens are predominantly the rapidly growing mycobacteria. Amikacin, ciprofloxacin and clarithromycin are the most frequently used targeted antimicrobial agents but often show poor responses. Patients with deep infections may warrant a surgical operation or line withdrawal. With periodic multidrug therapy guided by drug susceptibility testing, and surgical managements, patients may achieve good therapeutic results.

Heart Valves; Endocarditis; Mycobacterium

Abbreviations, acronyms & symbols
AVR	Aortic valve replacement
M.	Mycobacterium
MVR	Mitral valve replacement

Predisposing risk factors	n (%)
Cardiac operation	27 (54)
MVR	9 (33.3)
AVR	5 (18.5)
AVR + coronary artery bypass grafting	1 (3.7)
Composite AVR	1 (3.7)
MVR + AVR	1 (3.7)
Redo-MVR + AVR	3 (11.1)
Redo-AVR	2 (7.4)
Mitral valve ring plasty with aortic valve repair	1 (3.7)
Ventricular septal defect patch repair	3 (11.1)
Atrial septal defect patch closure	1 (3.7)
Foreign material implant	11 (22)
Pacemaker	4 (36.4)
Percutaneous coronary intervention	3 (27.3)
Automatic implantable cardioverter defibrillator implant	1 (9.1)
Dialysis, catheter infection, immunosuppressive therapy	1 (9.1)
Hemodialysis	1 (9.1)
Stenting of the abdominal aorta + renal angioplasty	1 (9.1)
IDU	5 (10)
IDU alone	2 (40)
IDU + human immunodeficiency virus infection	2 (40)
IDU + tricuspid endocarditis (Methicillin-resistant Staphylococcus aureus)	1 (20)
Miscellaneity	7 (14)
Colostomy and colostomy revision	1 (14.3)
Left foot gangrene	1 (14.3)
Annular subvalvular left ventricular aneurysm (ASLVA)	1 (14.3)
Rheumatic heart disease	1 (14.3)
Radiation therapy + previous infective endocarditis	1 (14.3)
Travel to El Salvador	1 (14.3)
Not stated	1 (14.3)

Infection site	Non-tuberculous	Tuberculous	χ²	P value
	(n = 56)	(n = 8)
Aortic valve	16 (28.6)	3 (37.5)	0.3	0.605
Mitral valve	15 (26.8)	2 (25)	0.0	0.915
Aortic valve, prosthetic	5 (8.9)	0 (0)	1.4	0.237
Lead	5 (8.9)	0 (0)	1.4	0.237
Tricuspid valve	5 (8.9)	2 (25)	1.9	0.173
Mitral valve, prosthetic	2 (3.6)	0 (0)	0.5	0.460
Pulmonary valve	2 (3.6)	0 (0)	0.5	0.460
VSD patch	2 (3.6)	0 (0)	0.5	0.460
ASD patch	1 (1.8)	0 (0)	0.3	0.603
Right atrium	1 (1.8)	1 (12.5)	2.7	0.103
Right subclavian dialysis catheter	1 (1.8)	0 (0)	0.3	0.603
Sternum	1 (1.8)	0 (0)	0.3	0.603

Pathogen	Aortic valve	Mitral valve	χ²	P value
	(n=22)	(n=20)
Chelonae	8 (36.4)	11 (55)	1.5	0.226
Fortuitum	6 (27.3)	1 (5)	3.7	0.053
Abscessus	3 (13.6)	3 (15)	0.0	0.900
Chimaera	1 (4.5)	1 (5)	0.0	0.945
Peregrinum	1 (4.5)	0 (0)	1.4	0.235
Rapidly growing mycobacteria	1 (4.5)	0 (0)	1.4	0.235
Goodii	0 (0)	1 (5)	1.7	0.199
Neoaurum	0 (0)	1 (5)	1.7	0.199
Tuberculous	2 (9.1)	2 (10)	0.0	0.920

Initial blood culture	n (%)	References
Negative	18 (40)	[11,14,25,27,28,30]
Acid-fast bacteria	9 (20)	[7,10,13,22,23,35,36]
Gram-positive bacilli/rod	5 (11.1)	[15,20,26,31,33]
Atypical mycobacterial infection	1 (2.2)	[37]
Non-tuberculous mycobacteria	1 (2.2)	[38]
Rapidly growing mycobacteria	1 (2.2)	[34]
Mycobacterium species	1 (2.2)	[21]
Fortuitum	4 (8.9)	[9,12,17,24]
Abscessus	1 (2.2)	[18]
Neoaurum	1 (2.2)	[34]
Chimaera	1 (2.2)	[14]
Peregrinum	1 (2.2)	[16]
Tuberculous	1 (2.2)	[19]

Strain	Cardiac operation	Foreign material implant	Injective drug use	Miscellaneity	χ²	P value
Chelonae	14 (51.9)	1 (9.1)	0 (0)	2 (50)	40.4	0.000
Fortuitum	6 (22.2)	5 (45.5)	2 (33.3)	0 (0)	9.3	0.025
Chimaera	2 (7.4)	0 (0)	0 (0)	0 (0)	8.0	0.046
Abscessus	1 (3.7)	3 (27.3)	1 (16.7)	2 (50)	2.1	0.558
Goodii	1 (3.7)	0 (0)	0 (0)	0 (0)	4.0	0.261
Massiliense	1 (3.7)	0 (0)	0 (0)	0 (0)	4.0	0.261
Neoaurum	1 (3.7)	0 (0)	1 (16.7)	0 (0)	2.7	0.446
Peregrinum	1 (3.7)	1 (9.1)	0 (0)	0 (0)	2.7	0.446
Rapidly growing mycobacteria	0 (0)	1 (9.1)	0 (0)	0 (0)	4.0	0.261
Tuberculosis	0 (0)	0	2 (33.3)	2 (50)	8.0	0.046

Authors’ roles & responsibilities
SMY	Main Author

Sociedade Brasileira de Cirurgia Cardiovascular Rua Afonso Celso, 1178 Vila Mariana, CEP: 04119-061 - São Paulo/SP Brazil, Tel +55 (11) 3849-0341, Tel +55 (11) 5096-0079 - São Paulo - SP - Brazil
E-mail: bjcvs@sbccv.org.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] Correspondence address: Shi-Min Yuan, Longdejing Street, 389 - Chengxian District, Putian, Fujian Province, People's Republic of China. E-mail: shi_min_yuan@yahoo.com