Tubulointerstitial Injury and Drugs of Abuse.
Drug abuse is widespread in many populations, and patients abusing illicit substances are at a significantly increased risk of kidney injury. The tubulointerstitial compartment is a common target of these nephrotoxic agents. This review will cover some of the common illicit drugs and will focus on the tubulointerstitial injuries seen in the setting of drug abuse. Agents addressed in this review are synthetic cannabinoids, bath salts, ecstasy, anabolic steroids, inhaled solvents, heroin, and cocaine. The most frequent biopsy findings are those of acute tubular necrosis and acute interstitial nephritis. Unfortunately, histology is often unable to sufficiently narrow the differential diagnosis and point to a single likely cause. A high suspicion for drug abuse as a potential cause of kidney injury is needed to identify the patients for whom this is the cause of their kidney failure. Toxicology screens are often of little use in identifying patients using emerging drugs of abuse.