CLINICAL HANDBOOK OF SCHIZOPHRENIA

130 II. ASSESSMENT AND DIAGNOSISHCV: Anti-HCV Screening AssaysAnti-HCV screening test kits licensed or approved by the U.S. Food and Drug Administrationcomprise three immunoassays: two EIAs (Abbott HCV EIA 2.0, Abbott Laboratories,Abbott Park, IL, and ORTHO® HCV Version 3.0 ELISA, Ortho-Clinical Diagnostics, Raritan, NJ) and one enhanced chemiluminescence immunoassay (CIA; VITROS®Anti-HCV Assay, Ortho-Clinical Diagnostics, Raritan, NJ). All of these immunoassaysuse HCV-encoded recombinant antigens.Confirmatory Testing: Recombinant Immunoblot Assay and PCRThe Centers for Disease Control and Prevention have recommended that a person be consideredto have serological evidence of HCV infection only after an anti-HCV screeningtest-positiveresult has been verified by a more specific serological test (e.g., the recombinantimmunoblot assay [RIBA®; Chiron Corporation, Emeryville, CA]) or a nucleic acidtest (NAT). This recommendation is consistent with testing practices for hepatitis B surfaceantigen and antibody to HIV, for which laboratories routinely conduct more specificreflex testing before reporting a result as positive.Treatment of HIV infection is recommended for almost all infected persons, preferablyprior to the onset of significant immune deficiency. Treatment of HCV with antiviralmedication may be recommended for persons with moderately severe liver disease, whichis assessed by symptoms, physical examination, laboratory tests, and, in some cases, liverbiopsy. Infected persons should be referred to a medical specialist for treatment.Diabetes MellitusMETABOLIC CONDITIONSThere is about an 8% prevalence rate of diabetes in the general population of NorthAmerica. Rates among people with schizophrenia are much higher, with reported ratesranging from 16 to 25%. Second-generation antipsychotics, obesity, and lifestyle factorscan all contribute to the increase in prevalence. Patients at high risk for developing diabetesshould be assessed. Risk factors include obesity; age greater than 45 years; family historyof diabetes; being African American, Native American, Asian American, Pacific Islander,or Hispanic American; and blood pressure greater than 140/90 or history of highblood pressure, high cholesterol, or inactive lifestyle. If a patient is 45 years or older andoverweight, testing is recommended. If the patient is younger than age 45, overweight,and has at least one of the aforementioned risk factors, testing is recommended. Testing isable to indicate whether blood glucose is normal, prediabetic, or diabetic. If a patient isdiagnosed with prediabetes, testing is indicated at least every 1–2 years. People diagnosedwith prediabetes often develop diabetes within 10 years. Regular testing for diabetes isnow generally recommended for patients who receive antipsychotic medications.Testing MethodsFasting plasma glucose measures blood glucose after the patient has fasted for at least 8hours. A level of 99 or less is normal, and a level of 126 or above is consistent with diabetes.An oral glucose tolerance test measures blood glucose after the patient has fasted forat least 8 hours and 2 hours after drinking a glucose-containing beverage. A level of 139or less is normal, and a level of 200 or above is consistent with diabetes. Levels in betweenare considered impaired fasting glucose, or prediabetic. A random plasma glucose