Thrombotic Thrombocytopenic Purpura (TTP)–Like Illness Associated With Intravenous Opana ER Abuse—Tennessee, 2012
Journal: JAMA (2013)

Thrombotic Thrombocytopenic Purpura (TTP)-Like Illness Associated withIntravenous Opana ER Abuse -Tennessee, 2012On 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 (1,2).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 (1,3,4).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 TTPlike 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. Clinical CharacteristicsFollowing report of the initial three cases, TDH contacted infectious disease specialists, dialysis centers, and the regional poison center in Tennessee seeking additional cases.A case of TTP-like illness was defined as microangiopathic hemolytic anemia (hemolytic anemia based on haptoglobin and lactate dehydrogenase and the presence of schistocytes) and thrombocytopenia in a person with a hospital admission platelet count ≤50,000/µL, in the absence of certain known causes of TTP.By the end of October 2012, a total of 15 cases had been reported in Tennessee.TDH interviewed patients in person and reviewed medical charts.Among the 15 patients, 13 were women.All were white; none were pregnant.The 15 patients ranged in age from 22 to 49 years (median: 34 years).The earliest diagnosis of TTP-like illness was April 16, 2012 (Figure).Seven of the 15 patients were from the same rural county in northeast Tennessee; five were from nearby counties, and three were from counties in middle Tennessee.The 15 patients were further categorized by presence or absence of a concurrent infection (as evidenced by sepsis) as a possible etiology.Clinical characteristics were similar among patients with and without infection (Table ).Patients reported symptoms typical of TTP-like illness, including nausea (11 patients) abdominal pain (11), fatigue (10), and fever (six).Seven patients were treated for sepsis.Twelve were treated with plasmapheresis.The median admission platelet counts for patients without and with infection were 20,000/µL (range: 9,000-40,000/µL) and 26,000/µL (range: 9,000-49,000/µL), INSIDE