Dr Sharon Chen1, Dr John Ng1, Dr Kathryn Wales1, Dr Bruce Cleland1, Dr Jeffery Wong1
1Liverpool Hospital, , Australia
Biography:
Bio to come
Background:
Non-tuberculous mycobacteria infective endocarditis is a rare infection in solid organ transplantation, primarily described in case reports. It often responds poorly to antimicrobial therapy and carries a high mortality rate. We describe a case of Mycobacterium fortuitum infective endocarditis in an immunosuppressed renal transplant recipient with a permanent pacemaker and a mitral valve annuloplasty.
Case Report:
A frail 76-year-old female with a history of renal transplant on immunosuppression, tissue aortic valve replacement, mitral valve annuloplasty, permanent pacemaker, heart failure with preserved ejection fraction, chronic type 2 respiratory failure, obstructive sleep apnoea, and multiple atraumatic fractures presented with acute dyspnoea, fever, and cough. She was initially treated with intravenous piperacillin/tazobactam due to her immunosuppressed status but remained febrile until blood cultures grew Mycobacterium fortuitum. Transoesophageal echocardiography and PET imaging confirmed infective endocarditis of the mitral valve and probable vegetation on the pacing wire.
She was commenced on a regimen including imipenem, linezolid, and doxycycline, but treatment was complicated by seizures and cytopenia due to imipenem and linezolid respectively. Amikacin was avoided due to renal impairment. Surgical intervention was not feasible due to her frailty and comorbidities. The regimen was subsequently rationalised to cefoxitin, moxifloxacin, and doxycycline.
After a complicated admission lasting many months, her infective endocarditis is now stable, with lifelong suppressive therapy planned using moxifloxacin and doxycycline
Conclusion:
This case highlights the potential for atypical organisms causing severe infections in immunosuppressed renal transplant recipients. Management of Mycobacterium fortuitum infective endocarditis involving prosthetic material was particularly challenging due to renal impairment limiting antimicrobial options and the development of significant treatment-related adverse effects.