Table 1.

Causes of blood culture negative endocarditis

Antibiotics given prior to taking blood culturesTrue BCNENon-infective BCNE
Coxiella
Bartonella spp
Brucella
Tropheryma whipplei Mycobacteria spp (M chimera following cardiac surgery)
Fungi (Aspergillus)
May be diagnosed by:

  • Serology (Bartonella currently unavailable in UK)

  • PCR of excised valve / embolectomy material

Behçet's disease
Systemic lupis erythematosus (Libman–Sacks endocarditis)
Marantic (breast/lung/prostate/colon cancer)

  • BCNE = blood culture negative endocarditis.