BIRMINGHAM, Ala.—University of Alabama at Birmingham (UAB) nephrologists have reported for the first time in medical literature cases of acute kidney injury (AKI) directly linked with synthetic marijuana use. The case studies are reported online in the Clinical Journal of the American Society of Nephrology and will appear in the March 2013 print edition of the journal.
The authors report that nephrotoxicity—the poisonous effect of a substance on the kidneys—from designer drugs such as SPICE or K2, which mimic the effects of marijuana but are human-made and cannot be detected in routine drug tests, should be considered when a patient presents with AKI and no other evident cause. This is especially true for young adults with negative urine drug screens, said the paper's senior author Denyse Thornley-Brown, MD, associate professor in the UAB Division of Nephrology.
Thornley-Brown said the use of relatively cheap synthetic marijuana preparations has increased significantly over the past few years, mostly among young adults who have a desire to experiment with a substance that is difficult to detect. The relatively low cost, about $20 per gram, is another reason for its popularity.
In the journal, Thornley-Brown and colleagues outlined four different cases of previously healthy young men whose AKI was linked to ingestion of synthetic marijuana. All the patients were residents of the same northeastern Alabama community and presented to UAB or a community hospital within a nine-week period showing symptoms of nausea, vomiting and abdominal pain after using synthetic marijuana.
"Cases of acute coronary syndrome associated with synthetic marijuana use have been reported, but our publication is the first to associate use with acute kidney injury," said study co-author Gaurav Jain, MD, assistant professor in the Division of Nephrology. "Tachycardia and seizures have also been reported with synthetic cannabinoids."
Three of the patients had AKI marked by the excretion of an abnormally small volume of urine, known asoliguric AKI, and the fourth had a decrease in effective blood flow to the kidney, known as prerenal AKI. Three of the patients underwent a kidney biopsy that showed acute tubular necrosis, which is the death of cells that form the minute canals in the kidney that secrete, reabsorb, collect and transport urine. Left untreated, this can cause the kidneys to shut down. In these four cases, the patients recovered kidney function, and none required dialysis.