Aggravation of symptom severity in adult attention-deficit/hyperactivity disorder by latent Toxoplasma gondii infection: a case-control study.

Toxoplasma gondii (T. gondii) has a high worldwide prevalence and an underestimated impact on neuropsychiatric disorders. Previous studies related T. gondii to disorders associated with the dysfunctional dopaminergic system. However, an association between T. gondii infection and adult attention-deficit/hyperactivity disorder (ADHD) has not yet been studied. In a sex- and age-matched case-control study, we investigated the seropositivity, serointensity, and avidity of latent T. gondii infection in adult ADHD patients and examined the influence of those variables on the symptomatology of ADHD. Of 140 participants, 20.0% were seropositive for anti-T. gondii IgG and 0% for anti-T. gondii IgM. T. gondii seropositivity was associated with 2.8-fold increase in the odds of ADHD in a confounder-adjusted multivariable analysis. Age and consumption of raw/undercooked meat were confirmed as significant predictors of T. gondii seropositivity. Multiple linear regression analysis of self-rated ADHD-related symptom severity in all participants revealed a significant association with T. gondii seropositivity, elevated IgG titers (serointensity), and stronger anti-T. gondii IgG avidity. Overall symptom severity was increased in seropositive ADHD patients compared to seronegative subjects with ADHD. In particular, hyperactivity was significantly associated with serointensity. We conclude that there is a high rate of T. gondii seropositivity in adults with ADHD. Additionally, our results suggest a clinical impact of latent T. gondii infection on ADHD-related symptoms in a serointensity- and avidity-dependent manner.

Whole blood interleukin-8 concentrations in capillary and cord blood of neonates for the diagnosis of systemic inflammatory states.

An assay is described for the determination of interleukin 8 (IL-8) in whole blood lysate instead of plasma or serum. EDTA-anticoagulated umbilical cord blood or capillary blood was added to a detergent-containing lysing reagent. This sample was used directly for determination of IL-8 using the Immulite IL-8 assay kit (DPC, Bad Nauheim, Germany) and the Immulite Analyzer. Linearity was confirmed for cord blood as well as for venous blood, at a whole blood to lysing agent ratio from 1:20 to 1:1. IL-8 was stable in whole blood hemolysate at 4 degrees C for at least 3 days; thereafter, concentrations decreased remarkably to 32% of the initial concentration after 8 days. Storage of whole blood prior to hemolysis led to increases in IL-8 concentrations of up to 4 fold the original values. The intra-assay CV was 3.4% (at 234 ng/l) and 7.4 % (at 1080 ng/l) using hemolysate samples. Inter-assay CVs of 13.3% (at 108 ng/l) and 11.7 % (at 506 ng/l) were found using control material. Concentrations of IL-8 in whole blood were significantly higher than in the corresponding plasma. In 70% of 135 apparently healthy neonates' cord blood samples, plasma IL-8 concentrations were below the detection limit of the assay (5 ng/l), whereas a range of 69 - 3150 ng/l IL-8 (median, 266 ng/l) was found in the hemolysate samples of these neonates. A preliminary reference range for IL-8 in whole blood may be set at 132 to 820 ng/l (5th and 95th percentile). In 78 neonates, IL-8 concentrations in hemolysate from capillary blood ranged from 120 ng/l to 2000 ng/A (median, 416 ng/l). The fact that concentrations of IL-8 can be determined using only a very small sample volume (10 microl of whole blood) makes the assay format especially suitable for use in neonatal intensive care.

Role of N-terminal pro-B-type natriuretic peptide in risk stratification in patients presenting in the emergency room.

BACKGROUND: Natriuretic peptides are promising markers in diagnosing acute and chronic heart failure and assessing prognosis in these patients. Increasing routine use to unselected patients is challenged by false-positive results. The aims of this study were to assess (a) the distributions of N-terminal B-type natriuretic peptide (NT-proBNP) values in various diagnostic groups, (b) factors that influence NT-proBNP, and (c) the value of NT-proBNP in risk stratification in unselected emergency room (ER) patients. METHODS: NT-proBNP was measured in 876 unselected consecutive patients [mean (SD) age, 58 (18) years; 53% male] attending the ERs of 2 university hospitals and 1 community hospital. Diagnoses, age, sex, hemoglobin, creatinine (CREA), C-reactive protein (CRP), troponin T, and intensity of care were documented. In a subset consisting of all 417 patients at 1 center, in-hospital follow-up was completed with respect to a complicated clinical course, including intensive care treatment and death. RESULTS: NT-proBNP was significantly increased in patients with cardiac diagnoses or histories compared with patients with only pulmonary or other diagnoses. In patients with other diagnoses, NT-proBNP values increased significantly with the number of atherosclerotic risk factors (P=0.044). Age, renal function, CRP, and to a much lesser extent, hemoglobin significantly influenced NT-proBNP values. The amount of care was positively correlated with NT-proBNP (P<0.001). Classification and regression tree analysis showed a superior impact of NT-proBNP for identification of high-risk patients. CONCLUSIONS: NT-proBNP is a promising marker for identification of patients with structural heart disease in the ER and a suitable tool for risk stratification. Its use in the ER should be limited to clearly clinically defined patient groups at present to avoid a potential excess of additional diagnostic procedures in positive but asymptomatic patients.