Renal transplant related complications

The recipients of renal transplants are susceptible to a number of complications. The incidence of each is variable and partially subject to specific surgical transplantation techniques and management patterns. 

Pathology

Renal transplant complications

These can be broadly categorized as perirenal, renal parenchymal, renal collecting system, and/or renal vascular complications ^1,2:

• perioperative acute tubular necrosis

• renal cortical necrosis

• renal allograft compartment syndrome

• renal allograft torsion (rare) ⁷

• renal transplant rejection

  • acute renal transplant rejection

  • chronic renal transplant rejection

• renal arterial stenosis in the transplant renal artery ³:

  • peak systolic velocity (PSV) >200 cm/s

  • 2:1 PSV ratio between stenotic and prestenotic artery

  • spectral broadening distally (i.e. turbulent flow)

  • +/- renal parenchymal tardus-parvus waveform

• renal vein thrombosis

• acute perioperative renal artery thrombosis

• arteriovenous fistula

• perinephric fluid collection: occurring roughly in the order below post-surgery

  • hematoma

  • urinoma

  • abscess

  • lymphocele

• renal artery pseudoaneurysm

• urinary obstruction ³

  • although usually presents within the first 6 months following the transplant, may occur years later

  • clinically presents with rising creatinine and absence of renal colic (renal allograft is denervated)

  • site of obstruction is typically near transplant ureter / native bladder anastomosis

  • causes of obstruction ³

    • transplant ureter stenosis (most commonly due to scarring, kinking, or secondary to anastomotic technique)

    • less commonly pelvic fibrosis, calculi, papillary necrosis, external compression

• graft pyelonephritis ⁴

• infections ⁶:

  • nosocomial and procedure-related

    • occurring <1 month after transplantation

    • donor related infections: HSV, rabies, West Nile virus

    • recipient acquired infections: Aspergillus spp., Pseudomonas spp.

  • latent, prior and opportunistic

    • occurring 1-6 months after transplantation

    • depending if the patient is on pneumocystis pneumonia and antiviral prophylaxis

    • with: BK virus, HCV, adenovirus, influenza, Cryptococcus neoformans, Mycobacterium tuberculosis

    • without: Pneumocystis jirovecii, Herpes family, HBV, Listeria, Nocardia, Toxoplasma spp. 

  • community-acquired

    • occurring >6 months after transplantation

    • urinary tract infection, late viral infections and others (e.g. Nocardia, Aspergillus)

• donor-related malignancy

Extra-renal transplant complications

• osteonecrosis  

• amyloidosis

• metastatic joint calcification

• increased incidence of malignancy: e.g. lymphoma

• pseudoaneurysm

• posttransplantation lymphoproliferative disorder ¹⁰

Treatment and prognosis

The 1-year survival rate of deceased renal allografts were over 93% in 2014 ⁵.