A study published in the American Journal of Transplantation recently shows that organs that come from donors with a history of recent cannabis use don’t show signs of infection or significant risk.
The study was conducted by a handful of researchers from University of California, San Francisco, University of Pennsylvania, and Temple University, and funded by National Institutes of Health, the Centers for Disease Control and Prevention (CDC), and Transplant Foundation Innovative Research Grant Program. Researchers examined information from three specific transplant centers located in Philadelphia, Pennsylvania, between transplants that were conducted by the Gift of Life Program between January 1, 2015-June 30, 2016.
According to the CDC, organ transplant patients take anti-rejection medicine that lowers their body’s immune system response, which helps their bodies accept the new organ. That same medicine can sometimes lead to mild or life-threatening infections, which can develop days, weeks, months, or even years after transplant surgery occurs.
The authors explained that cannabis leaves sometimes contain harmful bacteria or fungi, and inhaled cannabis has also been found in relation to infections in transplant patients. This study addressed the question regarding if cannabis consumer’s organs are harmful to patients on the organ receiving end. “The goal of our study is to better characterize the infection risks that marijuana use among deceased organ donors may pose to [solid organ transplants] recipients,” the authors wrote.
The authors explained the importance of their findings amidst the rising percentage of people consuming cannabis regularly. “It is likely that a growing proportion of deceased organ donors have a history of marijuana use, as well, though this metric has not been specifically reported,” authors said.
The study examined donors with cannabis use within the last 12 months prior to the study, as well as donors with no recent cannabis use history. “Despite concern that donor exposure to marijuana increases the risk of fungal infection in recipients, our study found that a donor history of marijuana use did not increase (1) the likelihood of donor culture positivity (including respiratory cultures), or (2) the risk of early recipient bacterial or fungal infection, graft failure, or death posttransplant,” the study stated. “Even when evaluating only lung recipients, there remained no association between donor marijuana use and the risk of posttransplant infection.”
The researchers explored a variety of data from the three transplant facilities, such as donors who experienced bacterial or fungal infections, or if the transplant failed and led to death in the patient. Overall, organs from consumers with recent cannabis use posed little threat to the patients. “Among donors with a history of recent marijuana use, 79 (89%) had at least 1 positive culture, compared to 264 (87%) among those with no history of marijuana use,” researchers wrote. “On donor respiratory cultures, 76 (85%) donors with a history of recent marijuana use and 250 (82%) donors with no history of recent marijuana use had bacterial or fungal growth on respiratory cultures. On both unadjusted analyses and multivariable analyses, there was no association between recent donor marijuana use and donor culture positivity.”
However, it’s important to note that the data that researchers reviewed was collected well after transplants occurred, and relied on next-of-kin to help measure a patient’s cannabis use. This was described as an “imperfect measure” of data collection.
“In conclusion, our study demonstrates that donors with a history of recent marijuana use are not more likely to have positive donor cultures, and their recipients are not more likely to develop a bacterial or fungal infection, graft failure, or death in the early posttransplant period (in the context of current management),” the study concluded. “These results suggest that organs from donors with a history of recent marijuana use do not pose significant novel infectious risks to recipients in the early posttransplant period.”
Currently, medical cannabis patients often experience discrimination when seeking out health care, but specifically encounter restrictions when it comes to organ transplants, according to a report published by the Petrie-Flom Center at Harvard Law School last October. “Many transplant centers prevent cannabis users from receiving solid organ transplantation due to concerns regarding interactions between cannabis and immunosuppressant drugs used for transplants, treatment non-adherence, fungal infections, and neuropsychiatric effects,” the report stated. As a result, medical cannabis patients are often ineligible for transplant.
The review adds that larger-scale studies are needed in order to determine if medical cannabis consumption “…should not be an absolute contraindication to solid organ transplantation.” Furthermore, some research shows evidence of medical cannabis helping to prevent transplant rejection in some patients.
Last year, another study found that cannabis use isn’t a risk for liver transplant patients. Researchers found no correlation between cannabis and non-cannabis users, stating that there was “no statistically significant associations between marijuana use with post-transplant bacterial or fungal infections, medication non-compliance, or continued substance use.”
