Prolonged renal replacement therapy linked to aspergillosis after kidney transplantation

A recent research paper has demonstrated for the first time that the risk of invasive aspergillosis within 3 months after renal transplant surgery increases when longer periods of renal replacement therapy (also commonly known as kidney dialysis) are required before surgery. The occurrence of leukopenia - a decrease in the number of white blood cells was also identified as another risk factor.

Quoting Emily Shafer of Infectious Disease News on March 10th:

“In solid organ transplantation in general, renal failure and the need of renal replacement therapy after transplantation are independent risk factors for [invasive aspergillosis],” the researchers wrote in Clinical Infectious Diseases. “Our results demonstrate for the first time an increased susceptibility with longer duration of renal replacement therapy before transplantation.”

Line Heylen, MD, of the department of nephrology at the University Hospitals Leuven in Belgium, and colleagues conducted a case-control study to evaluate the specific risk factors associated with invasive aspergillosis after kidney transplantation. The retrospective study included 41 kidney transplant recipients who were diagnosed with invasive aspergillosis from 1995 to 2013. The controls included 82 patients who underwent kidney transplant immediately before or after each case patient and did not develop invasive aspergillosis.

Leukopenia after transplant was associated with an increased risk for invasive aspergillosis in all patients (OR = 2.345; 95% CI, 1.084-5.071). Patients who developed invasive aspergillosis early — within 3 months after transplantation — had a longer duration of renal replacement therapy before transplant (3.57 years vs. 2.04 years; P = .019). Having leukopenia within the 3 months after transplant also was associated with early invasive aspergillosis (P = .049).

Neither duration of renal replacement therapy nor early leukopenia were risk factors for late invasive aspergillosis. A cytomegalovirus-positive donor increased the risk for late invasive aspergillosis (P = .007).

The 12-week mortality rate for patients with invasive aspergillosis was 39%. Factors associated with mortality included height of serum galactomannan index (HR = 1.371; 95% CI, 1.123-1.674), leukopenia (HR = 3.198; 95% CI, 1.183-8.649) and disseminated infection (HR = 5.08; 95% CI, 1.74-14.83).

“The higher serum galactomannan level is thought to represent a higher Aspergillus burden and/or increased micro- or macro-dissemination,” the researchers wrote. “In our cohort, disseminated [invasive aspergillosis] increased the risk for death, similar to what has been reported elsewhere.”