An Image quiz : What is the Investigation & What is the diagnosis ?
October 6, 2023 by dr s venkatesan
Image courtesey : Sekhar, S. et al Canadian Journal of Cardiology, 2015 (Ref 2)
Coronary stent infection (CSI) is no longer a rare and fancy diagnosis. It is increasingly recognized and is equivalent to infective endocarditis. Though CSI appear simple & practical terminology, Infective endo-coronary arteritis may be the ideal term for this device-related infection.
Any prolonged fever following PCI must be investigated with this condition in mind. Unlike other forms of infective endocarditis, vegetations are rare, or do not occur . Instead, the infection erodes endothelium, often leading to the development of an infective aneurysm. Staphylococcus infections seems to more common. Though host immunity is a factor, it is possible inadequate cathlab sterility plays a major role.
Diagnosis
Conventional IE criteria may not be fulfilled. PET scanning helps us to detect & map the active inflammation in the peri-stent area.(See the Image) The PET criteria to define significant inflammation are not yet standardized. One possible differential diagnosis to CSI is, acute or subacute allergic stent rejection.(Not Kuonis syndrome)
Treatment
Is complex, and carries a high mortality rate. It is best to manage it without any aggressive intervention. Physical removal of the infectious focus, along with the stent, may seem like an ideal option.
However, real-world scenarios often preclude this option as exceptional surgical expertise and team work is needed as in this report (Ref 3)
Reference
There is an excellent meta-analysis on this rare entity by Nagendra Boopathy and others from my place Chennai (Ref 1)