Evidence-based diagnosis of Lyme disease.

The aim of this study was to make an evidence-based comparison of four commercial enzyme immunoassays (EIAs) (Serion Classics, Sigma Diagnostics, Cambridge Biotech and ICN Diagnostics) and an in-house enzyme immunoassay (EIA) in order to select the most appropriate screening assay for diagnosis of Lyme disease. Borrelia burgdorferi sensu stricto cultured in BSK-H medium was used to develop the in-house assay. Escherichia coli antigen (0.9 mg/ml) was included in the serum diluent to reduce non-specific background. Comparison of the number of tests needed to diagnose (i.e. to indicate a positive result) and the cost per positive diagnosis for the five assays was made using a panel of 176 Western blot-characterised sera. The Cambridge Biotech and Sigma assays had the highest sensitivity but poorer specificity, whereas the Serion and ICN assays had highest specificity but poorer sensitivity. The in-house assay had average sensitivity and specificity, the number of tests needed to diagnose being 2.32 compared to 1.92 for Serion, 2.17 for ICN, 2.5 for Sigma and 2.7 for Cambridge Biotech. In a diagnostic protocol that uses an EIA as screening test, with confirmation by Western blot, a good balance of sensitivity and specificity is essential. The in-house assay was the most cost-effective (lowest cost per positive diagnosis), and is probably the best option for specialist laboratories in Europe.

Selected MMPI-2 scales' ability to predict premature termination and outcome from psychotherapy.

Research examining the MMPI's ability to predict premature termination has yielded discrepant findings. This may be due, in part, to previous operational definitions of premature termination and extensive analysis on inadequately sized samples. This study addressed both methodological issues. This study examined MMPI-2 clinical Scales 2, 4, and 7 and content scales DEP, ASP, ANX, and TRT as predictors of premature termination and psychotherapeutic outcome in 86 adult clients seeking services at a university-based clinic. Premature termination was operationalized as therapists' ratings of clients' readiness for termination. Psychotherapeutic outcome was operationalized as therapists' ratings of the clients' progress in therapy goals, improvement in global psychopathology, improvement in current functioning, and global improvement. None of MMPI-2 scales predicted readiness for termination. However, significant associations were found between specific MMPI-2 scales and three of the four outcome ratings, with the content scales emerging as better predictors. The implications of these findings are discussed to help guide future research in this area.

Improved serodiagnosis of Lyme disease.

Aims-To determine whether enzyme linked immunosorbent assay (ELISA) results for Borrelia burgdorferi require confirmation by immunoblotting and how immunoblotting may best be used in the diagnosis of Lyme disease.Methods-Over one year, all referrals for Lyme disease to a district general hospital with a large tick population in its catchment area were tested by ELISA. Positive, low positive and negative serum samples were subjected to immunoblotting and the reactive bands analysed.Results-In total, 633 samples were received; 38 were ELISA positive and 97 low positive. More serum samples were from rural (n = 356) than from urban (n = 277) areas but a higher percentage of serum samples from urban areas were ELISA positive. The ELISA results were confirmed by immunoblotting in 15/38 positive samples but in only four of 37 with a low positive titre. An IgM positive blot required a 41 kDa band plus >/=1 specific band; for IgG a 41 kDa band plus >/=2 specific bands were necessary. Five serum samples were IgM positive with a 41 kDa plus one or more other specific bands. For IgG blots, the best discrimination was seen with the 21, 31, 46, and 92 kDa bands. Nonspecific, weakly reacting bands at 55, 60 and 67 kDa were frequently seen. Infection was confirmed in four of six patients with arthritis, but in only one of 10 patients with erythema chronicum migrans.Conclusions-ELISA alone is insufficient for diagnosis. All positive and low positive or negative serum samples with a good clinical history should be examined by immunoblotting. A higher percentage of modified ELISA positive than low positive results were confirmed. There are significant differences between European and American immunoblotting patterns. Local results show similarity to American results, highlighting the need for a local Borrelia isolate.

Assessment of rapid ELISA test for detection of Epstein-Barr virus infection.

A rapid test for the detection of IgM and IgG Epstein-Barr nuclear antigen (EBNA-1) has been extensively marketed. If IgM to Epstein-Barr viral capsid antigen (EBV VCA) is taken as evidence of current EBV infection, one observer detected 17 of 38 such samples and the other 22 of 38 as acute. The positive predictive value of the test was 63%, and the greatest difficulty was posed by the detection of IgM EBV VCA positive, heterophile antibody negative samples. Significant false positive results were obtained in sera with evidence of current Toxoplasma gondii, cytomegalovirus, and adenovirus infection. Rheumatoid factor was not a problem. Modification of the test protocol improved its performance: the positive predictive value rose to 87% and the negative predictive value to 81%. Although our modifications did not increase the speed of the test, there was reliable information on the EBNA-1 state. The test is best used as an adjunct to other EBV serology, and laboratories should be aware of the limitations of the rapid test.