Refined diagnostic criteria for the bipolar disorders: phase two of the AREDOC project.

OBJECTIVE: As limitations exist across DSM criteria sets for defining and differentiating the bipolar disorders generally and their component bipolar I (BP-1) and bipolar II (BP-II) sub-types, we sought to generate empirically based criteria. METHOD: We formed an international Task Force (TF) comprising members with bipolar disorder expertise, and who recruited 74 patients with a TF-diagnosed bipolar I and 104 with a bipolar II condition (with patients responding to definitional queries and symptom questionnaires), while 33 unipolar depressed patients recruited by the first author also completed the symptom questionnaire. A factor analysis sought to determine granular hypo/manic constructs. RESULTS: The bipolar disorder subjects strongly affirmed a new general definition of a bipolar disorder (capturing both manic and hypomanic episodes). While DSM-5 requires impaired functioning, we established that a high percentage of individuals with a BP-I or a BP-II disorder reported improved functioning and therefore modified this criterion. Analyses identified syptoms with differential high rates in individuals with bipolar disorder and its sub-types (and thus not simply capturing happiness), while a factor analysis generated seven symptom constructs both linked with and differing from DSM-5 bipolar symptom criteria. CONCLUSION: This second-stage report details a new set of criteria for differentiating the bipolar disorders from unipolar depressive conditions, while arguing for BP-I and BP-II disorders being differentiated principally by the respective presence or absence of psychotic features. Future studies will evaluate whether further modifications are required and examine for differential treatment benefits for those with a BP-I versus a BP-II condition.

Prediction of lithium response using clinical data.

OBJECTIVE: Promptly establishing maintenance therapy could reduce morbidity and mortality in patients with bipolar disorder. Using a machine learning approach, we sought to evaluate whether lithium responsiveness (LR) is predictable using clinical markers. METHOD: Our data are the largest existing sample of direct interview-based clinical data from lithium-treated patients (n = 1266, 34.7% responders), collected across seven sites, internationally. We trained a random forest model to classify LR-as defined by the previously validated Alda scale-against 180 clinical predictors. RESULTS: Under appropriate cross-validation procedures, LR was predictable in the pooled sample with an area under the receiver operating characteristic curve of 0.80 (95% CI 0.78-0.82) and a Cohen kappa of 0.46 (0.4-0.51). The model demonstrated a particularly low false-positive rate (specificity 0.91 [0.88-0.92]). Features related to clinical course and the absence of rapid cycling appeared consistently informative. CONCLUSION: Clinical data can inform out-of-sample LR prediction to a potentially clinically relevant degree. Despite the relevance of clinical course and the absence of rapid cycling, there was substantial between-site heterogeneity with respect to feature importance. Future work must focus on improving classification of true positives, better characterizing between- and within-site heterogeneity, and further testing such models on new external datasets.

Cerebellar parcellation in schizophrenia and bipolar disorder.

OBJECTIVE: The cerebellum is involved in cognitive processing and emotion control. Cerebellar alterations could explain symptoms of schizophrenia spectrum disorder (SZ) and bipolar disorder (BD). In addition, literature suggests that lithium might influence cerebellar anatomy. Our aim was to study cerebellar anatomy in SZ and BD, and investigate the effect of lithium. METHODS: Participants from 7 centers worldwide underwent a 3T MRI. We included 182 patients with SZ, 144 patients with BD, and 322 controls. We automatically segmented the cerebellum using the CERES pipeline. All outputs were visually inspected. RESULTS: Patients with SZ showed a smaller global cerebellar gray matter volume compared to controls, with most of the changes located to the cognitive part of the cerebellum (Crus II and lobule VIIb). This decrease was present in the subgroup of patients with recent-onset SZ. We did not find any alterations in the cerebellum in patients with BD. However, patients medicated with lithium had a larger size of the anterior cerebellum, compared to patients not treated with lithium. CONCLUSION: Our multicenter study supports a distinct pattern of cerebellar alterations in SZ and BD.

Larger right inferior frontal gyrus volume and surface area in participants at genetic risk for bipolar disorders.

BACKGROUND: Larger grey matter volume of the inferior frontal gyrus (IFG) is among the most replicated biomarkers of genetic risk for bipolar disorders (BD). However, the IFG is a heterogeneous prefrontal region, and volumetric findings can be attributable to changes in cortical thickness (CT), surface area (SA) or gyrification. Here, we investigated the morphometry of IFG in participants at genetic risk for BD. METHODS: We quantified the IFG cortical grey matter volume in 29 affected, 32 unaffected relatives of BD probands, and 42 controls. We then examined SA, CT, and cortical folding in subregions of the IFG. RESULTS: We found volumetric group differences in the right IFG, with the largest volumes in unaffected high-risk and smallest in control participants (F2,192 = 3.07, p = 0.01). The volume alterations were localized to the pars triangularis of the IFG (F2,97 = 4.05, p = 0.02), with no differences in pars opercularis or pars orbitalis. Pars triangularis volume was highly correlated with its SA [Pearson r(101) = 0.88, p < 0.001], which significantly differed between the groups (F2,97 = 4.45, p = 0.01). As with volume, the mean SA of the pars triangularis was greater in unaffected (corrected p = 0.02) and affected relatives (corrected p = 0.05) compared with controls. We did not find group differences in pars triangularis CT or gyrification. CONCLUSIONS: These findings strengthen prior knowledge about the volumetric findings in this region and provide a new insight into the localization and topology of IFG alterations. The unique nature of rIFG morphology in BD, with larger volume and SA early in the course of illness, could have practical implications for detection of participants at risk for BD.

Identifying a neuroanatomical signature of schizophrenia, reproducible across sites and stages, using machine learning with structured sparsity.

OBJECTIVE: Structural MRI (sMRI) increasingly offers insight into abnormalities inherent to schizophrenia. Previous machine learning applications suggest that individual classification is feasible and reliable and, however, is focused on the predictive performance of the clinical status in cross-sectional designs, which has limited biological perspectives. Moreover, most studies depend on relatively small cohorts or single recruiting site. Finally, no study controlled for disease stage or medication's effect. These elements cast doubt on previous findings' reproducibility. METHOD: We propose a machine learning algorithm that provides an interpretable brain signature. Using large datasets collected from 4 sites (276 schizophrenia patients, 330 controls), we assessed cross-site prediction reproducibility and associated predictive signature. For the first time, we evaluated the predictive signature regarding medication and illness duration using an independent dataset of first-episode patients. RESULTS: Machine learning classifiers based on neuroanatomical features yield significant intersite prediction accuracies (72%) together with an excellent predictive signature stability. This signature provides a neural score significantly correlated with symptom severity and the extent of cognitive impairments. Moreover, this signature demonstrates its efficiency on first-episode psychosis patients (73% accuracy). CONCLUSION: These results highlight the existence of a common neuroanatomical signature for schizophrenia, shared by a majority of patients even from an early stage of the disorder.

A hemiparasite in the forest understorey: photosynthetic performance and carbon balance of Melampyrum pratense.

Melampyrum pratense is an annual root-hemiparasitic plant growing mostly in forest understorey, an environment with unstable light conditions. While photosynthetic responses of autotrophic plants to variable light conditions are in general well understood, light responses of root hemiparasites have not been investigated. We carried out gas exchange measurements (light response and photosynthetic induction curves) to assess the photosynthetic performance of M. pratense in spring and summer. These data and recorded light dynamics data were subsequently used to model carbon balance of the hemiparasite throughout the entire growth season. Summer leaves had significantly lower rates of saturated photosynthesis and dark respiration than spring leaves, a pattern expected to reflect the difference between sun- and shade-adapted leaves. However, even the summer leaves of the hemiparasite exhibited a higher rate of light-saturated photosynthesis than reported in non-parasitic understorey herbs. This is likely related to its annual life history, rare among other understorey herbs. The carbon balance model considering photosynthetic induction still indicated insufficient autotrophic carbon gain for seed production in the summer months due to limited light availability and substantial carbon loss through dark respiration. The results point to potentially high importance of heterotrophic carbon acquisition in M. pratense, which could be of at least comparable importance as in other mixotrophic plants growing in forests - mistletoes and partial mycoheterotrophs. It is remarkable that despite apparent evolutionary pressure towards improved carbon acquisition from the host, M. pratense retains efficient photosynthesis and high transpiration rate, the ecophysiological traits typical of related root hemiparasites in the Orobanchaceae.

Connectivity of the anterior insula differentiates participants with first-episode schizophrenia spectrum disorders from controls: a machine-learning study.

BACKGROUND: Early diagnosis of schizophrenia could improve the outcomes and limit the negative effects of untreated illness. Although participants with schizophrenia show aberrant functional connectivity in brain networks, these between-group differences have a limited diagnostic utility. Novel methods of magnetic resonance imaging (MRI) analyses, such as machine learning (ML), may help bring neuroimaging from the bench to the bedside. Here, we used ML to differentiate participants with a first episode of schizophrenia-spectrum disorder (FES) from healthy controls based on resting-state functional connectivity (rsFC). METHOD: We acquired resting-state functional MRI data from 63 patients with FES who were individually matched by age and sex to 63 healthy controls. We applied linear kernel support vector machines (SVM) to rsFC within the default mode network, the salience network and the central executive network. RESULTS: The SVM applied to the rsFC within the salience network distinguished the FES from the control participants with an accuracy of 73.0% (p = 0.001), specificity of 71.4% and sensitivity of 74.6%. The classification accuracy was not significantly affected by medication dose, or by the presence of psychotic symptoms. The functional connectivity within the default mode or the central executive networks did not yield classification accuracies above chance level. CONCLUSIONS: Seed-based functional connectivity maps can be utilized for diagnostic classification, even early in the course of schizophrenia. The classification was probably based on trait rather than state markers, as symptoms or medications were not significantly associated with classification accuracy. Our results support the role of the anterior insula/salience network in the pathophysiology of FES.

[A study of the morphology of the descending branch of the lateral circumflex femoral artery (DBLCFA) as a possible vascular graft for the reconstruction of coronary arteries using angio CT]. / Studie morfologie r. descendens a. circumflexae femoris lateralis jako mozné cévní náhrady pro rekonstrukci koronárního reciste pomocí angio CT vysetrení

INTRODUCTION: Due to the need for alternative arterial grafts suitable for the reconstruction of the coronary bloodstream, we conducted a morphological analysis of the descending branch of the lateral circumflex femoral artery (DBLCFA) using an AGCT scan. MATERIAL AND METHODS: Not only anatomical variations and the quantitative representation of sclerotic changes, but also the presence of a collateral system in the event of significant stenosis of the pelvic and femoral artery system were analysed. RESULTS: The results revealed favorable findings in the sense of the studied arteries length (9.3 cm on average), a relatively low anatomical variability and a very small percentage of the studied blood vessels participating in collateral blood flow, despite that 72% of tests revealed significant stenotic disease (stenosis of more than 50%) of the upper branch of lower limb arteries. CONCLUSION: According to the defined criteria, 68% of vessels were found to be suitable for grafting. We suppose that this number would be considerably higher in patients with only insignificant or no ischemic disease of the lower extremities.

Desiccation tolerance of Sphagnum revisited: a puzzle resolved.

As ecosystem engineers, Sphagnum mosses control their surroundings through water retention, acidification and peat accumulation. Because water retention avoids desiccation, sphagna are generally intolerant to drought; however, the literature on Sphagnum desiccation tolerance (DT) provides puzzling results, indicating the inducible nature of their DT. To test this, various Sphagnum species and other mesic bryophytes were hardened to drought by (i) slow drying; (ii) ABA application and (iii) chilling or frost. DT tolerance was assessed as recovery of chlorophyll fluorescence parameters after severe desiccation. We monitored the seasonal course of DT in bog bryophytes. Under laboratory conditions, following initial de-hardening, untreated Sphagnum shoots lacked DT; however, DT was induced by all hardening treatments except chilling, notably by slow drying, and in Sphagnum species of the section Cuspidata. In the field, sphagna in hollows and lawns developed DT several times during the growing season, responding to reduced precipitation and a lowered water table. Hummock and aquatic species developed DT only in late autumn, probably as a response to frost. Sphagnum protonemata failed to develop DT; hence, desiccation may limit Sphagnum establishment in drier habitats with suitable substrate chemistry. Desiccation avoiders among sphagna form compact hummocks or live submerged; thus, they do not develop DT in the field, lacking the initial desiccation experience, which is frequent in hollow and lawn habitats. We confirmed the morpho-physiological trade-off: in contrast to typical hollow sphagna, hummock species invest more resources in water retention (desiccation avoidance), while they have a lower ability to develop physiological DT.

Neuroprotective effect of lithium on hippocampal volumes in bipolar disorder independent of long-term treatment response.

BACKGROUND: Neuroimaging studies have demonstrated an association between lithium (Li) treatment and brain structure in human subjects. A crucial unresolved question is whether this association reflects direct neurochemical effects of Li or indirect effects secondary to treatment or prevention of episodes of bipolar disorder (BD). METHOD: To address this knowledge gap, we compared manually traced hippocampal volumes in 37 BD patients with at least 2 years of Li treatment (Li group), 19 BD patients with <3 months of lifetime Li exposure over 2 years ago (non-Li group) and 50 healthy controls. All BD participants were followed prospectively and had at least 10 years of illness and a minimum of five episodes. We established illness course and long-term treatment response to Li using National Institute of Mental Health (NIMH) life charts. RESULTS: The non-Li group had smaller hippocampal volumes than the controls or the Li group (F 2,102 = 4.97, p = 0.009). However, the time spent in a mood episode on the current mood stabilizer was more than three times longer in the Li than in the non-Li group (t(51) = 2.00, p = 0.05). Even Li-treated patients with BD episodes while on Li had hippocampal volumes comparable to healthy controls and significantly larger than non-Li patients (t(43) = 2.62, corrected p = 0.02). CONCLUSIONS: Our findings support the neuroprotective effects of Li. The association between Li treatment and hippocampal volume seems to be independent of long-term treatment response and occurred even in subjects with episodes of BD while on Li. Consequently, these effects of Li on brain structure may generalize to patients with neuropsychiatric illnesses other than BD.

[Traumatic rupture of thoracic aorta]. / Traumatická ruptura hrudní aorty.

INTRODUCTION: Thoracic aortic injury (TAI) is burdened with high mortality (80-90%). The diagnostic and therapeutic algorithm has changed radically over the last couple of years. The authors present their experience with diagnosis and treatment of TAI at the University Hospital Trauma Centre. MATERIAL AND METHODS: 24 TAIs were evaluated in a retrospective study, in 20 (83.3%) cases they were part of a polytrauma. The average age of the patients was 39.4 years (20-67). Traffic accidents formed the majority of TAIs (87.5%). Multi-detector computed tomography was used as a basic examination to detect TAI. Thoracic endovascular aortic repair (TEVAR) was the treatment of choice in 21 and open surgery in 3 injured patients. RESULTS: The 30-day postoperative mortality was 12.5%, in one case it was associated with TEVAR. 30-day morbidity was 37.5% (circulatory instability, respiratory insufficiency, bronchopneumonia, type I endoleak). CONCLUSION: MDCT and TEVAR are currently the methods of first choice in the diagnosis and treatment of TAI. TAI requires a highly specialized multidisciplinary approach within Trauma Centres providing complex cardiovascular services.

Are minimized perfusion circuits the better heart lung machines? Final results of a prospective randomized multicentre study.

INTRODUCTION: Minimized perfusion circuits (MPCs), although aiming at minimizing the adverse effects of cardiopulmonary bypass, have not yet gained popularity. This can be attributed to concerns regarding their safety, as well as lack of sufficient evidence of their benefit. METHODS: Described is a randomized, multicentre study comparing the MPC - ROCsafeRX to standard cardiopulmonary bypass in patients undergoing elective coronary artery bypass grafting and/ or aortic valve replacement. RESULTS: Five hundred patients were included in the study (252 randomized to the ROCsafeRX group and 248 to standard cardiopulmonary bypass). Both groups were well matched for demographic characteristics and type of surgery. No operative mortality and no device-related complications were encountered. Transfusion requirement (333 ± 603 vs. 587 ± 1010 ml; p=0.001), incidence of atrial fibrillation (16.3% vs. 24.2%; p=0.03) and the incidence of major adverse events (9.1% vs. 16.5%; p=0.02) were all in favour of the MPC group. CONCLUSION: These results confirm both the safety and efficacy of the ROCsafeRX MPC for a large variety of cardiac patients. Minimized perfusion circuits should, therefore, play a greater role in daily practice so that as many patients as possible can benefit from their advantages.

[Alternative autologous arterial graft in cardiovascular surgery]. / Alternativní autologní tepenný step v kardiovaskulární chirurgii.

Arterial revascularization of myocardium is a method of choice for surgical treatment of ischemic heart disease. The descending branch of lateral femoral circumflex artery (DBLFCA) is one of possible alternative autologous arterial grafts. Up to now, since 2003, 12 of these grafts have been harvested and used for revascularization of myocardium at our department. All grafts have been used as a Y-graft to the left internal mammary artery for revascularization of target vessels on lateral and inferior heart wall. Graft patency was controlled by the angio-CT procedure after three months. One of the grafts was occluded at the control. It means patency rate after three months was more than 91%. No other complications (such as problematic wound healing, paraesthaesia of lower leg, bleeding, spasm of the graft, infection etc.) were observed with graft harvesting. DBLCFA is a high-quality and safe alternative arterial graft, available for arterial revascularization of myocardium.

Lithium response across generations.

OBJECTIVE: To describe and integrate observations from bipolar patients responsive to lithium stabilization and their children. METHOD: Selected findings are described from the clinical and biological investigations of adults meeting research criteria for bipolar disorder and for responsiveness to lithium stabilization; and from prospective studies of the children of lithium responders and non-responders. RESULTS: Response to prophylactic lithium identifies a valid subtype of bipolar disorder, however the search for biological markers of lithium response, while promising, has so far remained inconclusive. Adult responders to lithium stabilization exhibit definable clinical features which are also observable in their affected children. In prospective studies the children of bipolar parents develop symptoms earlier than reported previously, with marked differences between the offspring of lithium responders and non-responders. The illness evolves in predictable clinical stages, first from non-specific sleep and anxiety disorders to mood symptoms and then, often starting in adolescence, major depressive and later activated episodes. CONCLUSION: Investigating and comparing unequivocal responders and non-responders to long-term lithium treatment and their offspring is a fertile research strategy for addressing a multitude of clinical and research questions.

Beneficial effects of modern perfusion concepts in aortic valve and aortic root surgery.

Minimized perfusion circuits (MPC) were found to reduce side effects of standard extracorporeal circulation (ECC). We evaluated the safety and efficacy of the ROCsafe MPC for aortic valve and aortic root surgery. One hundred and seventy patients were randomized for surgery using either MPC [n = 85, 30 female/55 male, mean age: 69.8 +/- 11.8 years; aortic valve replacement (AVR): n = 40; AVR + coronary artery bypass graft (CABG): n = 31; David operation: n = 3; aortic root replacement (ARR): n = 11] or ECC [n = 85, 29 female/56 male, mean age: 67.7 +/- 9.5 years; AVR: n = 39; AVR+CABG: n = 35, David operation: n = 2; ARR: n = 9]. Neurological status, length of ICU stay, C-reactive protein (CRP), blood count, transfusion requirements and bleeding volume were analyzed. The MPC system provided ultrasound-controlled de-airing. A small roller pump and a flexible reservoir were used for left ventricular venting. As a control, we used a standard ECC with cardiotomy suction and hard-shell reservoir. Cross-clamp time (MPC: 76.5 +/- 29.5; ECC: 79.0 +/- 34.0 min) and bypass time (MPC: 103.0 +/- 37.9; ECC: 106.9 +/- 44.9 min) were comparable between groups. Transfusion requirements (red blood cells: MPC: 1.5 +/- 1.5 vs. ECC: 2.2 +/- 2.1 units [p = 0.05], frozen plasma: MPC: 1.2 +/- 1.8 vs. ECC: 1.9 +/- 2.4 units [p = 0.03]), postoperative bleeding (MPC: 521 +/- 283 vs. ECC: 615 +/- 326 ml/24 h, p = 0.09) were lower using MPC. ICU stay was shorter with MPC (1.6 +/- 1.6 days) compared to ECC (2.4 +/- 2.8 days, p = 0.001). One stroke occurred in each group. The ROCsafe MPC provides safe circulatory support for a wide range of aortic valve surgeries. Transfusion requirements, postoperative bleeding and length of ICU stay were markedly reduced compared to standard extracorporeal perfusion.

Effects of borneol and thymoquinone on TNBS-induced colitis in mice.

Components of plant essential oils have been reported to have health benefit properties, including antioxidative, anti-tumour, antimicrobial, anti-stress, and immunomodulative activities. We examined the anti-inflammatory effects of thymoquinone, the active ingredient in the volatile oil of Nigella sativa seeds, and borneol, the active component of Salvia officinalis essential oil, on TNBS-induced colitis in mice. Thymoquinone was added to the commercial diet at a concentration of 0.05 % and borneol at two concentrations (0.09% and 0.18%) and fed to ICR mice 5 days before induction of TNBS colitis. Seven days after TNBS administration the mice were killed and macroscopic and histological scores were evaluated. Cytokine mRNA expression in colonic tissue was assessed using quantitative realtime RT-PCR. We did not detect any significant changes in macroscopic and histological scores between experimental and control groups, but we observed a significant decrease in proinflammatory cytokine (IL-1beta and IL-6) mRNA expression in colon tissue in the 0.09% and 0.18% borneol-treated groups of mice in comparison to the control group. Surprisingly, we were not able to confirm anti-inflammatory effects of thymoquinone in TNBS colitis. In conclusion, our data show that borneol is able to significantly suppress proinflammatory cytokine mRNA expression in colonic inflammation, although no significant morphological changes are visible.

Different functional responsibility of the small intestine to high-fat/high-energy diet determined the expression of obesity-prone and obesity-resistant phenotypes in rats.

The objective of the present experiment was to assess the involvement of small intestine in expression of susceptibility or resistance to the high-fat/high-energy diet. The investigation was carried out in adult male Sprague-Dawley rats fed either standard laboratory diet (3.2 kcal/g, 9.5 % fat) or high-fat (HF) diet (4.04 kcal/g, 30 % fat) for 4 weeks as well as in HF rats that were retrospectively designated on the bases of their higher or lower weight gain as sensitive (DIO) or resistant (DR) to obesity. Our results revealed in HF group significant increase in energy intake, food efficiency, weight gain and Lee s index of obesity. Moreover, in comparison with controls, a significantly increased duodenal and jejunal alkaline phosphatase (AP) and alpha-glucosidase activity as well as hypertrophy of jejunal mucosa (increased protein/DNA ratio) were observed in HF fed rats. In contrast, intestinal function was inversely related to energy intake or to the development of adiposity in DIO vs. DR rats. The DR rats had significantly greater AP and alpha-glucosidase activity and more pronounced suppression of energy intake than obese DIO rats. It indicates that the increase of enzyme activities and the lowered effectiveness of nutrient absorption might be a significant factor preventing the expression of obesity proneness. This information contributes to a better understanding of a complex interaction between HF diet feeding and small intestinal adaptability, which determines the energy homeostasis and predict the ability to resist or develop obesity in these phenotypes.

Tumor markers in pleural effusions.

AIM: The aim of this study was to determine the diagnostic capabilities of tumor markers in pleural effusion and their importance for assessment of the etiology of pleural effusions. PATIENTS AND METHODS: In pleural effusions from 166 patients hospitalized during the period 2003-2005 at the Department of Oncology and Radiotherapy, Faculty Hospital in Pilsen, the following tumor markers were determined: thymidine kinase (TK), neuron-specific enolase (NSE), cytokeratins [tissue polypeptide antigen (TPA), tissue polypeptide-specific antigen (TPS) and cytokeratin fragment 19 (CYFRA 21-1)], carcinoembryonic antigen (CEA) and mucinous markers (CA 15-3, CA 19-9, CA 125). The inflammatory marker procalcitonin-PCT was also assessed. RESULTS: Tumor markers CA 125, TPA, TPS were significantly elevated in exudates, irrespective of the etiology, as a non-specific reaction in mesothelial cells. TK had a sensitivity of over 80% for all the types of cancer examined, while CA 15-3 had a sensitivity of over 90%. CONCLUSION: Significant positivity of PCT and CA 15-3 in pleural effusions indicate a suspicion of inflammatory disease. Positivity of TK and CA 15-3 indicate a strong suspicion of malignant exudates.

Clinical and demographic characteristics of psychiatric patients seropositive for Borrelia burgdorferi.

PURPOSE: Borrelia burgdorferi (Bb) infection can affect the central nervous system and possibly lead to psychiatric disorders. We compared clinical and demographic variables in Bb seropositive and seronegative psychiatric patients and healthy controls. METHOD: Nine hundred and twenty-six consecutive psychiatric patients were screened for antibodies to Bb and compared with 884 simultaneously recruited healthy subjects. RESULTS: Contrary to healthy controls, seropositive psychiatric patients were significantly younger than seronegative ones. None of the studied psychiatric diagnostic categories exhibited stronger association with seropositivity. There were no differences between seropositive and seronegative psychiatric patients in hospitalization length, proportion of previously hospitalized patients and proportion of subjects with family history of psychiatric disorders. CONCLUSION: These findings elaborate on potential association between Bb infection and psychiatric morbidity, but fail to identify any specific clinical 'signature' of Bb infection.