On August 13, 2012, a nephrologist reported to the Tennessee Department of Health (TDH) three cases of unexplained
thrombotic thrombocytopenic purpura (
TTP), a rare but serious blood disorder characterized by
microangiopathic hemolytic anemia and
thrombocytopenia. The annual incidence is approximately 1 per 100,000 population. Known risk factors for
TTP include
infection with Shiga toxin-producing Escherichia coli (STEC) and the use of drugs, including
platelet aggregation inhibitors,
quinine, and
cocaine. The three patients were intravenous (IV) drug users who resided in a rural county in northeast Tennessee. To identify other cases of
TTP-like illness that might be associated with injection-
drug use, TDH conducted a statewide investigation. By the end of October, a total of 15 such cases had been reported; none were fatal. A case-control study was conducted, and investigators determined that the cases of
TTP-like illness were associated with dissolving and injecting
tablets of
Opana ER (Endo
Pharmaceuticals), a recently reformulated extended-release form of
oxymorphone (an
opioid pain reliever) intended for
oral administration. Fourteen of the 15 patients reported injecting reformulated
Opana ER. Seven of the 15 were treated for
sepsis in addition to
TTP-like illness. Twelve patients reported
chronic hepatitis C or had positive test results for anti-HCV antibody. Health-care providers who prescribe
Opana ER and pharmacists who dispense it should inform patients of the risks from the
drug when used other than as prescribed. Health-care providers should ask patients with
TTP-like illness of unknown etiology about any IV
drug abuse. Suspected cases can be reported to public health officials.