Culture negative endocarditis: a diagnostic and therapeutic challenge!

Coxiella Endocarditis as the Cause of Recurrent Fever and Brain Abscess in a Patient with Complex Congenital Heart Disease: A Case Report and Literature Review

Introduction

Blood culture-negative infective endocarditis (BCNIE) can present subtly and is associated with a diagnostic delay leading to increased morbidity and mortality. Case Report. We present the case of an 18-year-old male with a history of complex congenital heart disease and 3-year intermittent episodes of fever of unknown origin, who was referred to our hospital for upper and lower extremity focal seizures. Laboratory blood tests were normal, blood cultures were negative, and brain imaging revealed an abscess. Cardiology consultation was requested, and transthoracic echocardiography revealed an intracardiac vegetation. Empiric antibiotic treatment with sultamicillin, gentamycin, and meropenem was initiated. Serology testing was positive for Coxiella burnetii, and the diagnosis of BCNIE was established. The antibiotic course was changed to oral doxycycline for 36 months and led to resolution of IE, with no vegetation detected on TTE after 15 months.

Conclusion

BCNIE is a life-threatening disease entity that can lead to severe complications, such as valve regurgitation, emboli, and death. Patients with congenital heart disease are particularly vulnerable to IE. Timely diagnosis and antibiotic management are of paramount importance in order to avoid the potentially fatal sequelae.

Blood Culture-Negative but Clinically Diagnosed Infective Endocarditis Complicated by Intracranial Mycotic Aneurysm, Brain Abscess, and Posterior Tibial Artery Pseudoaneurysm

Blood culture-negative endocarditis is often severe and difficult to diagnose. It is necessary to emphasize the importance for the early diagnosis and accurate treatment of blood culture-negative endocarditis. Here, we described the relevant clinical information of a blood culture-negative but clinically diagnosed infective endocarditis complicated by intracranial mycotic aneurysm, brain abscess, and posterior tibial artery pseudoaneurysm. This patient was a 65-year-old man with a 9-month history of intermittent fever and died in the end for the progressive neurological deterioration. Although the blood culture is negative, this patient was clinically diagnosed as infective endocarditis according to Duke criteria. This patient course was complicated not only by cerebral embolism, intracranial mycotic aneurysm, and brain abscess but also by posterior tibial artery aneurysm of the lower extremity. The clinical findings of this patient suggest that the confirmatory microbiology is essential for the treatment of blood culture-negative infective endocarditis. Clinicians should be aware of the detriment of blood culture-negative infective endocarditis for its multiple complications may occur in one patient. The delayed etiological diagnosis and insufficient treatment may aggregate the clinical outcome of blood culture-negative infective endocarditis.