AKI associated with synthetic cannabinoids: a case series

Abstract

SPICE, or K2, encompasses preparations of synthetic cannabinoids marketed as incense products, bath additives, and air fresheners and used for recreational purposes. These preparations are usually smoked for their cannabis-like effects and do not appear on routine urine toxicology screens. We report four cases of oliguric AKI associated with SPICE use in previously healthy men. All showed improvement in renal function without need for renal replacement therapy. Renal biopsy, performed in three of the patients, revealed acute tubular necrosis. The close temporal and geographic associations between the clinical presentation and the development of AKI strongly suggest an association between these SPICE preparations and AKI. Further investigations are required to identify the potential nephrotoxic agent(s). Nephrotoxicity from designer drugs should be included in the differential diagnosis of AKI, especially in young adults with negative urine drug screens.

Figure 1.

Pathologic features of AKI associated with SPICE. (A) Injured proximal tubular epithelial cells show apical blebbing from the surface and cytoplasmic vacuolization. Rare intraluminal detached necrotic tubular epithelial cells are also present. These findings are indicative of acute tubular injury. (B) Proximal tubular dilation with epithelial cell vacuolization and apical blebbing. Areas of denuded tubular basement membranes indicating focal epithelial cell loss are also identified. There is also accompanying interstitial edema. (C) The morphologic features of acute tubular injury are similar to the first two patients. All stained with periodic acid–Schiff. Original magnification, ×400 in A and B; ×200 in C.