Spontaneous Rupture of Transplant Renal Artery and External Iliac Artery Caused by Corynebacterium striatum

To the Editor:

Among Corynebacterium species, Corynebacterium striatum was traditionally regarded as a contaminant or a colonizer. C. striatum infection is rare in the general population, with only a few studies documented in the literature [1]. Because of C. striatum's low pathogenicity and adhesive properties, there are no serious complications of infected patients reported. We describe a case of multiple artery rupture, the renal and external iliac arteries, after C. striatum infection in a renal transplant recipient.

A 46-year-old man, with body weight of 120 kg, underwent renal transplantation from a deceased donor in mid-2019. Triple combinations of immunosuppressive therapy, including tacrolimus, mycophenolate mofetil (MMF), and a tapered dose of methylprednisolone, was employed as a routine. C. striatum was identified in drainage samples a few days after surgery. A month later, an apparent pseudoaneurysm of the allograft renal artery was found during a routine examination by Doppler ultrasonography. An exploratory operation was performed immediately, and we found a rupture of the allograft artery rather than a pseudoaneurysm. The arterial walls were fragile and easy to tear, which indicated that the vessel could not to be repaired. The transplanted kidney was removed, and the external iliac artery was repaired. C. striatum was identified in the allograft artery. After eight days, a sudden sharp pain in the iliac fossa appeared, and an exploratory operation was performed immediately. A rupture of the repaired external iliac artery was found, which presented an extremely brittle texture the same as the ruptured renal artery. The proximal and distal ends of the external iliac artery were ligated to stop the bleeding. An oxygen saturation detector was put on his toes and showed a satisfied artery pulse wave and oxygen saturation that was similar to that in the fingers. Thus, the bypass surgery was abandoned. C. striatum was identified in the external iliac artery samples. The temperature and movement of the ipsilateral leg were normal after the operation and remained so.

Most spontaneous ruptures of allograft renal arteries are cases of fungal infection, which invade the arterial wall [2]. Invasive fungal arteritis in immunosuppressed individuals can lead to serious complications, including graft loss and death, if the surgical repair of the impaired artery is delayed. We are the first to report the spontaneous rupture of both the renal and external iliac arteries caused by C. striatum, which can invade the arterial wall like a fungus in immunosuppressed individuals.

Bleeding from the rupture of the external iliac artery is a rather tricky problem for kidney transplant surgeons. Most of the surgeons selected bypass surgery after the ligation of the external iliac artery to avoid loss of the lower limbs [3,4]. About 3.3%–6.6% of patients whose external iliac artery has been ligated suffer loss their lower limbs, and bypass surgery may cause other vascular-related complications, including re-rupture, pseudoaneurysm, thrombosis, and so on. We provide a solution to predict the risk of lower limbs loss when the external iliac artery is ligated. Oxygen saturation detection in the toes is readily available in the operating room using the artery pulse wave and oxygen saturation. Whether bypass surgery is necessary can be determined immediately.