Objective  To explore the clinical and pathological characteristics of hemorrhagic necrotic inflammation due to Carbapenem-resistant Klebsiella pneumoniae allograft infection in early stage after kidney transplantation by summarizing its clinical manifestations, laboratory tests, imaging and pathological findings.

  Methods  A single-center, retrospective and descriptive study of CRKP infections in early stage (within 3 months after transplantation) after kidney transplantation in our hospital from January 2015 to December 2018 was performed. The infection characteristics, laboratory testing results and clinical outcomes were collected. Bacterial susceptibility was tested by Vitek2 system and disk diffusion.

  Results  The average age of 12 recipients was 45.7 years old and 8 cases were male. CRKP infections occurred within 1 month after transplant. The clinical manifestations included infection related systemic inflammatory response syndrome (11/12), hemorrhage (5/12) and purulent necrotic secretion (5/12), accompanied by the increase of infectious indexes such as leukocyte (12/12), C-reactive protein and procalcitonin (12/12). Clinical manifestations varied due to the duration of infection, and tissues /organs involved. Pathological examination showed presence of massive hemorrhage with acute inflammatory cell infiltration, and micro-abscess formation in the medulla of the transplanted kidney. Some CRKP were susceptible to tigecycline (9/12), and compound sulfamethoxazole (5/12).

  Conclusion  CRKP infection in early stage after kidney transplantation is essentially a necrotic hemorrhagic inflammation, which suggests an urgent need for monitoring the signs of suppurative and hemorrhagic inflammation to early diagnosis and treatment.