Comparison and evaluation of two C-reactive protein assays based on particle-enhanced immunoturbidimetry.

The use of C-reactive protein (CRP) assays is increasing for a wide range of clinical conditions, and consequently the analytical performance requirements for CRP assays are also changing. For this reason, manufacturers have been developing CRP assays based on different methodologies to provide both high sensitivity and a wide measuring range. However, it is questionable whether these methods can meet the desired requirements for CRP assays. CRP Latex on the Cobas Integra 400 and CRP Tina-quant Latex on the Modular Analytics-P were evaluated in terms of detection limit, linearity, intra- and interassay precision, and comparability with 268 patient samples. The intra- and interassay precision of the two methods was <4.1% in the three pools with CRP concentrations ranging from 6.9 to 215 mg/L, and >10% in the pool with concentrations of approximately 0.60 mg/L. The detection limits for CRP Latex and Tina-quant Latex were 0.20 and 0.22 mg/L, respectively. Both methods were linear up to 215 mg/L. There was a good agreement between the two assays, except for a scattering at concentrations near the detection limits. Deming regression analysis for CRP Latex (x-axis) and Tina-quant Latex (y-axis) yielded a slope of 1.067+/-0.018, an intercept of -0.148+/-0.358, and an S(y/x) of 5.10 (r=0.996, P<0.0001). The two assays gave comparable results. Low precision was determined for both assays, except for the low pool with a concentration of approximately 0.60 mg/L. We concluded that both of these assays should be improved to meet high-sensitivity criteria.

Nitric oxide levels in disruptive behavioral disorder.

There are various evidences of the role of nitric oxide (NO) in several neuropsychiatric disorders. However, there is no clinical study which investigated the role of NO in disruptive behavioral disorders (DBD). The aim of this study is to investigate the relation between NO levels and DBD. NO levels were measured in serum from 45 patients diagnosed as having DBD (30 patients with a diagnosis of attention deficit and hyperactivity disorder [ADHD] and 15 with ADHD + oppositional defiant disorder [ODD]) and 51 healthy control subjects. It is statistically significant that the pure ADHD group's blood NO levels are lower than those of both the ADHD + ODD and control groups. There was no significant difference between the ADHD + ODD group and the controls. The difference of the NO levels in DBD may indicate the effect of NO in the etiology of this disorder spectrum.

[The diagnostic validity of screening tests and laboratory markers in alcohol use disorders]. / Alkol Kullanim Bozukluklarinda Tarama Testleri ve Laboratuvar Belirteçlerinin Tanisal Etkinligi.

OBJECTIVE: To determine the validity of screening tests and markers suggested in the early detection of alcohol use disorders. METHOD: Male patients aged 20-65 were recruited from a psychiatry clinic. They had been consuming alcohol at least once a week. They were not drug users and had no other diseases that affected the markers mentioned in this study. According to the DSM-IV diagnostic criteria, the diagnostic validity of screening tests [Michigan Alcoholism Screening Test (MAST), CAGE (Cut down, Annoyed, Guilty, Eye-opener), Alcohol Use Disorders Identification Test (AUDIT)] and markers [Mean corpuscular volume (MCV), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), carbohydrate-deficient transferrin (CDT)] was investigated in alcohol dependent patients (n=29), alcohol abusers (n=28) and social drinkers (n=28). RESULTS: For the diagnosis of dependence, the sensitivity and specificity of the tests were respectively 69% and 100% for GGT, 41% and 93% for CDT, 100% and 57% for MAST, 97% and 86% for CAGE, and 100% and 75% for AUDIT. For the diagnosis of abuse, the sensitivity and specificity of the tests were respectively 32% and 100% for GGT, 32% and 93% for CDT, 86% and 57% for MAST, 75% and 85.7% for CAGE, and 89% and 75% for AUDIT. The widest area under the ROC curve belonged to GGT as a marker and AUDIT as a screening test. CONCLUSION: According to the results of this study, the marker that has the highest validity is GGT, while AUDIT and CAGE are the best screening tests.