[The most frequent febrile syndromes and autoinflammatory diseases in adulthood]. / Die häufigsten Fiebersyndrome und autoinflammatorischen Erkrankungen im Erwachsenenalter.

Autoinflammatory diseases are characterized by inflammatory manifestations in various organ systems, whereby recurrent febrile episodes, musculoskeletal complaints, gastrointestinal and cutaneous symptoms frequently occur accompanied by serological signs of inflammation. Autoinflammatory diseases include rare monogenic entities and multifactorial or polygenic diseases, which can manifest as a variety of symptoms in the course of time. Examples of monogenic autoinflammatory diseases are familial Mediterranean fever (FMF), cryopyrin-associated periodic syndrome (CAPS), tumor necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) and the recently described VEXAS (vacuoles, E1 enzyme, X­linked, autoinflammatory and somatic) syndrome. For non-monogenically determined autoinflammatory diseases, the most important representatives in adulthood are adult-onset Still's disease (AOSD) and the Schnitzler syndrome, in which a polygenic susceptibility and epigenetic factors are more likely to play a role.

VEXAS and Myelodysplastic Syndrome: An Interdisciplinary Challenge.

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a recently recognized systemic autoinflammatory disease caused by somatic mutations in hematopoietic progenitor cells. This case series of four patients with VEXAS syndrome and comorbid myelodysplastic syndrome (MDS) aims to describe clinical, imaging, and hematologic disease presentations as well as response to therapy. Four patients with VEXAS syndrome and MDS are described. A detailed analysis of imaging features, hemato-oncological presentation including bone marrow microscopy and clinical-rheumatological disease features and treatment outcomes is given. All patients were male; ages ranged between 64 and 81 years; all were diagnosed with MDS. CT imaging was available for three patients, all of whom exhibited pulmonary infiltrates of varying severity, resembling COVID-19 or hypersensitivity pneumonitis without traces of scarring. Bone marrow microscopy showed maturation-disordered erythropoiesis and pathognomonic vacuolation. Somatic mutation in the UBA1 codon 41 were found in all patients by next-generation sequencing. Therapy regimes included glucocorticoids, JAK1/2-inhibitors, nucleoside analogues, as well as IL-1 and IL-6 receptor antagonists. No fatalities occurred (observation period from symptom onset: 18-68 months). Given the potential underreporting of VEXAS syndrome, we highly recommend contemporary screening for UBA1 mutations in patients presenting with ambiguous signs of systemic autoinflammatory symptoms which persist over 18 months despite treatment. The emergence of cytopenia, especially macrocytic hyperchromic anemia, should prompt early testing for UBA1 mutations. Notably conspicuous, pulmonary alterations in CT imaging of patients with therapy-resistant systemic autoinflammatory symptoms should be discussed in interdisciplinary medical teams (Rheumatology, Hematology, Radiology and further specialist departments) to facilitate timely diagnosis during the clinical course of the disease.

Continuing versus tapering low-dose glucocorticoids in patients with rheumatoid arthritis and systemic lupus erythematosus in states of low disease activity or remission: A systematic review and meta-analysis of randomised trials.

OBJECTIVES: To study the benefit and harm associated with continuing versus tapering low-dose glucocorticoids (GCs) in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) who have achieved low disease activity/remission. METHODS: A protocolised (PROSPEROCRD42022325175) systematic review and meta-analysis of randomised trials was performed. Trials compared, in patients with low disease activity/remission and GCs at baseline, continued low-dose GCs (≤7.5 mg/d prednisone equivalent) with a taper. Co-primary outcomes were time to flare and adverse events (AEs), accompanied by secondary benefit and harm outcomes. We performed meta-analyses and evaluated risk of bias and quality of evidence (QoE). Subgroup analyses were conducted for patients with RA. RESULTS: Four trials (three: RA; one: SLE; study duration 24-104 weeks) with 472 participants were included. Tapering GCs resulted in a shorter time to flare (hazard ratio 3.41 [95 %-CI 1.96-5.93]; p<0.01; very low QoE). The risks of AEs, serious AEs, and withdrawal due to AEs were similar in both groups (very low to low QoE). There were more withdrawals due to lack of efficacy with tapered GCs (risk ratio 3.02 [1.56-5.87]; low QoE). In RA, the disease activity score-28 was lower with continued GCs (mean difference 0.49 [0.07-0.91]; low QoE). One of 238 patients in the tapering groups experienced adrenal insufficiency. Subgroup analyses yielded consistent results. CONCLUSION: In RA and SLE with low disease activity, continuing low-dose GCs may provide better sustained disease control, but QoE is insufficient. Adrenal insufficiency is very rare when tapering low-dose GCs. Longer-term safety concerns for GCs remain.

Mycophenolate mofetil in giant cell arteritis.

Introduction: Giant cell arteritis (GCA) is a systemic granulomatous vasculitis affecting the large arteries. Abnormal lymphocyte function has been noted as a pathogenic factor in GCA. Mycophenolate mofetil (MMF) inhibits inosine monophosphate dehydrogenase and is therefore a highly lymphocyte-specific immunosuppressive therapy. We aimed to assess the efficacy of MMF for inducing remission in GCA. Methods: Seven patients (5 female, 2 male) with GCA under therapy with MMF and who were treated at the outpatient clinic for rare inflammatory systemic diseases at Hannover Medical School between 2010 and 2023 were retrospectively included in the study. All patients underwent duplex sonography, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET), magnetic resonance imaging (MRI), and/or biopsy to confirm the diagnosis. The primary endpoints were the number of recurrences, CRP levels at 3-6 and 6-12 months, and the period of remission. Results: All patients in this case series showed inflammatory activity of the arterial vessels in at least one of the imaging modalities: duplex sonography (n = 5), 18F-FDG PET (n = 5), MRI (n = 6), and/or biopsy (n = 5). CRP levels of all patients decreased at the measurement time points 3-6 months, and 6-9 months after initiation of therapy with MMF compared with CRP levels before MMF therapy. All patients with GCA in this case series achieved disease remission. Discussion: The results of the present case series indicate that MMF is an effective therapy in controlling disease activity in GCA, which should be investigated in future randomized controlled trials.

[Autoinflammatory syndromes]. / Autoinflammatorische Syndrome.

The concept of autoinflammation includes a heterogeneous group of monogenic and polygenic diseases. These are characterized by excessive activation of the innate immune system without antigen-specific T cells or autoantibodies. The diseases are characterized by periodic episodes of fever and increased inflammation parameters. Monogenic diseases include familial Mediterranean fever (FMF) and the newly described VEXAS (vacuoles, E1 enzyme, X­linked, autoinflammatory, somatic) syndrome. Heterogeneous diseases include adult-onset Still's disease and Schnitzler syndrome. Treatment is aimed at preventing the excessive inflammatory reaction in order to avoid long-term damage, such as amyloid A (AA) amyloidosis.

Rare diseases: why is a rapid referral to an expert center so important?

BACKGROUND: Patients with rare diseases usually go through years of diagnostic odysseys. The large number of rare diseases and the associated lack of expertise pose a major challenge to physicians. There are few physicians dealing with patients with rare diseases and they usually work in a limited number of specialized centers. The aim of this study was to evaluate the diagnostic efficiency of an expert center. METHODS: The diagnostic pathway of 78 patients of the outpatient clinic for rare inflammatory systemic diseases with renal involvement was analyzed retrospectively. For this purpose, each examination day was documented with the corresponding examinations performed from the onset of initial symptoms. Three time points were considered: The time when patients first visited a physician with symptoms, the time when patients consulted an expert, and the time when they received the correct diagnosis. In addition, it was documented whether the diagnosis could be made without the expert, or only with the help of the expert. The examinations that confirmed the diagnosis were also documented for each patient. RESULTS: A correct diagnosis was made without the help of the expert in only 21% of cases. Each patient visited an average of 6 physicians before consulting the expert. Targeted diagnostics enabled the expert to make the correct diagnosis with an average of seven visits, or one inpatient stay. However, referral to the expert took an average of 4 years. CONCLUSION: The data show that rapid and targeted diagnostics were possible in the expert center due to the available expertise and the interdisciplinary exchange. Early diagnosis is of great importance for many patients, as an early and correct therapy can be decisive for the course of the disease.

[Autoinflammatory syndromes]. / Autoinflammatorische Syndrome.

The concept of autoinflammation includes a heterogeneous group of monogenic and polygenic diseases. These are characterized by excessive activation of the innate immune system without antigen-specific T cells or autoantibodies. The diseases are characterized by periodic episodes of fever and increased inflammation parameters. Monogenic diseases include familial Mediterranean fever (FMF) and the newly described VEXAS (vacuoles, E1 enzyme, X­linked, autoinflammatory, somatic) syndrome. Heterogeneous diseases include adult-onset Still's disease and Schnitzler syndrome. Treatment is aimed at preventing the excessive inflammatory reaction in order to avoid long-term damage, such as amyloid A (AA) amyloidosis.

Safety and efficacy associated with long-term low-dose glucocorticoids in rheumatoid arthritis: a systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to assess the safety and efficacy of long-term low-dose glucocorticoids (GCs) in RA. METHODS: A protocolised systematic review and meta-analysis (PROSPERO No. CRD42021252528) of double-blind, placebo-controlled randomised trials (RCTs) comparing a low dose of GCs (≤ 7.5mg/day prednisone) to placebo over at least 2 years was performed. The primary outcome investigated was adverse events (AEs). We performed random-effects meta-analyses and used the Cochrane RoB tool and GRADE to assess risk of bias and quality of evidence (QoE). RESULTS: Six trials with 1078 participants were included. There was no evidence of an increased risk of AEs (incidence rate ratio 1.08; 95% CI 0.86, 1.34; P = 0.52); however, the QoE was low. The risks of death, serious AEs, withdrawals due to AEs, and AEs of special interest did not differ from placebo (very low to moderate QoE). Infections occurred more frequently with GCs (risk ratio 1.4; 1.19-1.65; moderate QoE). Concerning benefit, we found moderate to high quality evidence of improvement in disease activity (DAS28: -0.23; -0.43 to -0.03), function (HAQ -0.09; -0.18 to 0.00), and Larsen scores (-4.61; -7.52 to -1.69). In other efficacy outcomes, including Sharp van der Heijde scores, there was no evidence of benefits with GCs. CONCLUSION: There is very low to moderate QoE for no harm with long-term low dose GCs in RA, except for an increased risk of infections in GC users. The benefit-risk ratio might be reasonable forusing low-dose long-term GCs considering the moderate to high quality evidence for disease-modifying properties.

Digital health information on autoinflammatory diseases: a YouTube quality analysis.

Getting access to specialists for autoinflammatory diseases (AID) can be challenging. Therefore, an increasing number of patients and healthcare professionals are seeking information on AID via the Internet, using the video platform YouTube, for example. However, the quality of such videos has not yet been evaluated. A YouTube search was conducted to assess videos about AID to evaluate the quality and usefulness from both the patient's and healthcare professional´s perspectives. Video duration, number of views, likes, dislikes, comments, and uploading source on various AID were extracted. Video quality was evaluated by the modified global quality scale (GQS). The reliability was assessed by the modified five-point DISCERN score. In total, 140 videos were screened of which 105 videos met the inclusion criteria for further analysis. Based on the GQS, the overall quality of videos for patients was found to be low in 64.8%, intermediate in 27.6%, and high in 7.6% of videos. The quality of videos for professionals was similar (54.3% low, 23.8% intermediate, and 21.9% of high quality). Videos were more often targeting medical professionals (65.7%) and less often patients (34.3%). This analysis demonstrates that the majority of videos regarding AIDs are of limited quality. Available videos more often address users with a professional medical background. Only a small proportion of existing videos provide understandable and useful information for AID patients. Thus, there is a strong need to develop high-quality and audience-oriented videos in the context of educational campaigns for these rare disease groups.

Transcriptional licensing is required for Pyrin inflammasome activation in human macrophages and bypassed by mutations causing familial Mediterranean fever.

Pyrin is a cytosolic immune sensor that nucleates an inflammasome in response to inhibition of RhoA by bacterial virulence factors, triggering the release of inflammatory cytokines, including IL-1ß. Gain-of-function mutations in the MEFV gene encoding Pyrin cause autoinflammatory disorders, such as familial Mediterranean fever (FMF) and Pyrin-associated autoinflammation with neutrophilic dermatosis (PAAND). To precisely define the role of Pyrin in pathogen detection in human immune cells, we compared initiation and regulation of the Pyrin inflammasome response in monocyte-derived macrophages (hMDM). Unlike human monocytes and murine macrophages, we determined that hMDM failed to activate Pyrin in response to known Pyrin activators Clostridioides difficile (C. difficile) toxins A or B (TcdA or TcdB), as well as the bile acid analogue BAA-473. The Pyrin inflammasome response was enabled in hMDM by prolonged priming with either LPS or type I or II interferons and required an increase in Pyrin expression. Notably, FMF mutations lifted the requirement for prolonged priming for Pyrin activation in hMDM, enabling Pyrin activation in the absence of additional inflammatory signals. Unexpectedly, in the absence of a Pyrin response, we found that TcdB activated the NLRP3 inflammasome in hMDM. These data demonstrate that regulation of Pyrin activation in hMDM diverges from monocytes and highlights its dysregulation in FMF.

Effectiveness and Safety of JAK Inhibitors in Autoinflammatory Diseases: A Systematic Review.

Introduction: Autoinflammatory diseases (AID) are rare diseases presenting with episodes of sterile inflammation. These involve multiple organs and can cause both acute organ damage and serious long-term effects, like amyloidosis. Disease-specific anti-inflammatory therapeutic strategies are established for some AID. However, their clinical course frequently includes relapsing, uncontrolled conditions. Therefore, new therapeutic approaches are needed. Janus Kinase inhibitors (JAKi) block key cytokines of AID pathogenesis and can be a potential option. Methods: A systematic review of the literature in accordance with the PRISMA guidelines was conducted. Three databases (MEDLINE, Embase and Cochrane Central Register of Controlled Trials) were searched for publications regarding the use of JAKi for AID. Data from the included publications was extracted and a narrative synthesis was performed. Criteria for defining treatment response were defined and applied. Results: We report data from 38 publications with a total of 101 patients describing the effects of JAKi in AID. Data on Type I Interferonopathies, Adult-Onset Still's Disease (AOSD), Systemic Juvenile Idiopathic Arthritis (sJIA), Familial Mediterranean Fever (FMF), and Behçet's Syndrome (BS) was identified. From a total of 52 patients with type I interferonopathies, in seven patients (7/52, 13.5%) a complete response was achieved, most (35/52, 67.3%) showed a partial response and a minority (10/52, 19.2%) showed no treatment response. For AOSD, a complete or a partial response was achieved by eleven (11/26, 42.3%) patients each. Two sJIA patients achieved complete response (2/4, 50%) and in two cases (2/4, 50%) a partial response was reported. Half of FMF patients showed a complete response and the other half had a partial one (3/6, 50.0%). Amongst BS patients most achieved a partial response (8/13, 61.5%). Five patients showed no response to therapy (5/13, 38.5%). Overall, the most frequent AEs were upper respiratory tract infections (17), pneumonia (10), BK virus viremia (10) and viruria (4), herpes zoster infection (5), viral gastroenteritis (2) and other infections (4). Conclusion: The results from this systematic review show that JAKi can be beneficial in certain AID. The risk of AEs, especially viral infections, should be considered. To accurately assess the risk benefit ratio of JAKi for AID, clinical trials should be conducted.

Rheumatology residency in a European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases centre: opportunities and challenges.

Rheumatology is a growing medical speciality with many attractive points to young doctors. Residency is a demanding period of a physician's life, and choosing the right hospital for one's residency may not be easy. We report on our personal experience as Rheumatology residents in European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases (ERN-ReCONNET) centres.

[What is confirmed in the diagnostics of autoinflammatory fever diseases?] / Was ist gesichert in der Diagnostik von autoinflammatorischen Fiebererkrankungen?

Periodic fever syndromes (PFS) are a group of rare autoinflammatory diseases, which are characterized by disorders of the innate immune reaction and life-long recurrent episodes of inflammatory symptoms. This article describes the diagnostic approach. In addition to the patient medical history, physical examination and laboratory determinations, gene tests are becoming increasingly more important. The panel diagnostics using high throughput sequencing or next generation sequencing (NGS) is the method of choice for the detection of a genetic cause of PFS. This article discusses the diagnostic decision support systems (DDSS) that can play a future role in the diagnosis of rare diseases, especially those with complex patterns of symptoms.

[What is confirmed in the treatment of autoinflammatory fever diseases?] / Was ist gesichert in der Therapie von autoinflammatorischen Fiebererkrankungen?

In the last 20 years the clarification of monogenic periodic febrile diseases has led to the independent concept of autoinflammation. In this heterogeneous group polygenic complex diseases are also now included. The spectrum of symptoms is continuously growing. The main difference to autoimmunity is an excessive activation of the innate immune system without formation of autoantibodies or antigen-specific T­cells. The cardinal symptom is recurrent fever episodes accompanied by signs of inflammation, which in the periodic manifestations alternate with intervals of general well-being. The classical monogenic diseases are also known as hereditary recurrent fever (HRF). Examples are familial Mediterranean fever (FMF), cryopyrin-associated periodic syndrome (CAPS), tumor necrosis factor receptor 1­associated periodic syndrome (TRAPS), adenosine deaminase 2 (ADA2) deficiency and mevalonate kinase deficiency (MKD, hyper-IgD syndrome). The polygenic diseases are also known as nonhereditary fever syndromes. These include adult-onset Still's disease (AoSD), Adamantiades-Behçet disease, the PFAPA syndrome (periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis) and gouty arthritis. All autoinflammatory fever syndromes are accompanied by a long-term risk of development of amyloid A amyloidosis, depending on the individual severity and treatment success. In some diseases severe complications can sometimes occur.

Aberrant Salience Is Related to Dysfunctional Self-Referential Processing in Psychosis.

BACKGROUND: A dysfunctional differentiation between self-relevant and irrelevant information may affect the perception of environmental stimuli as abnormally salient. The aberrant salience hypothesis assumes that positive symptoms arise from an attribution of salience to irrelevant stimuli accompanied by the feeling of self-relevance. Self-referential processing relies on the activation of cortical midline structures which was demonstrated to be impaired in psychosis. We investigated the neural correlates of self-referential processing, aberrant salience attribution, and the relationship between these 2 measures across the psychosis continuum. METHODS: Twenty-nine schizophrenia patients, 24 healthy individuals with subclinical delusional ideation, and 50 healthy individuals participated in this study. Aberrant salience was assessed behaviorally in terms of reaction times to task irrelevant cues. Participants performed a self-reference task during fMRI in which they had to apply neutral trait words to them or to a public figure. The correlation between self-referential processing and aberrant salience attribution was tested. RESULTS: Schizophrenia patients displayed increased aberrant salience attribution compared with healthy controls and individuals with subclinical delusional ideation, while the latter exhibited intermediate aberrant salience scores. In the self-reference task, schizophrenia patients showed reduced activation in the ventromedial prefrontal cortex (vmPFC), but individuals with subclinical delusional ideation did not differ from healthy controls. In schizophrenia patients, vmPFC activation correlated negatively with implicit aberrant salience attribution. CONCLUSIONS: Higher aberrant salience attribution in schizophrenia patients is related to reduced vmPFC activation during self-referential judgments suggesting that aberrant relevance coding is reflected in decreased neural self-referential processing as well as in aberrant salience attribution.

Prefrontal and Striatal Glutamate Differently Relate to Striatal Dopamine: Potential Regulatory Mechanisms of Striatal Presynaptic Dopamine Function?

Theoretical and animal work has proposed that prefrontal cortex (PFC) glutamate inhibits dopaminergic inputs to the ventral striatum (VS) indirectly, whereas direct VS glutamatergic afferents have been suggested to enhance dopaminergic inputs to the VS. In the present study, we aimed to investigate relationships of glutamate and dopamine measures in prefrontostriatal circuitries of healthy humans. We hypothesized that PFC and VS glutamate, as well as their balance, are differently associated with VS dopamine. Glutamate concentrations in the left lateral PFC and left striatum were assessed using 3-Tesla proton magnetic resonance spectroscopy. Striatal presynaptic dopamine synthesis capacity was measured by fluorine-18-l-dihydroxyphenylalanine (F-18-FDOPA) positron emission tomography. First, a negative relationship was observed between glutamate concentrations in lateral PFC and VS dopamine synthesis capacity (n = 28). Second, a positive relationship was revealed between striatal glutamate and VS dopamine synthesis capacity (n = 26). Additionally, the intraindividual difference between PFC and striatal glutamate concentrations correlated negatively with VS dopamine synthesis capacity (n = 24). The present results indicate an involvement of a balance in PFC and striatal glutamate in the regulation of VS dopamine synthesis capacity. This notion points toward a potential mechanism how VS presynaptic dopamine levels are kept in a fine-tuned range. A disruption of this mechanism may account for alterations in striatal dopamine turnover as observed in mental diseases (e.g., in schizophrenia). SIGNIFICANCE STATEMENT: The present work demonstrates complementary relationships between prefrontal and striatal glutamate and ventral striatal presynaptic dopamine using human imaging measures: a negative correlation between prefrontal glutamate and presynaptic dopamine and a positive relationship between striatal glutamate and presynaptic dopamine are revealed. The results may reflect a regulatory role of prefrontal and striatal glutamate for ventral striatal presynaptic dopamine levels. Such glutamate-dopamine relationships improve our understanding of neurochemical interactions in prefrontostriatal circuits and have implications for the neurobiology of mental disease.

Aberrant Salience Is Related to Reduced Reinforcement Learning Signals and Elevated Dopamine Synthesis Capacity in Healthy Adults.

The striatum is known to play a key role in reinforcement learning, specifically in the encoding of teaching signals such as reward prediction errors (RPEs). It has been proposed that aberrant salience attribution is associated with impaired coding of RPE and heightened dopamine turnover in the striatum, and might be linked to the development of psychotic symptoms. However, the relationship of aberrant salience attribution, RPE coding, and dopamine synthesis capacity has not been directly investigated. Here we assessed the association between a behavioral measure of aberrant salience attribution, the salience attribution test, to neural correlates of RPEs measured via functional magnetic resonance imaging while healthy participants (n = 58) performed an instrumental learning task. A subset of participants (n = 27) also underwent positron emission tomography with the radiotracer [(18)F]fluoro-l-DOPA to quantify striatal presynaptic dopamine synthesis capacity. Individual variability in aberrant salience measures related negatively to ventral striatal and prefrontal RPE signals and in an exploratory analysis was found to be positively associated with ventral striatal presynaptic dopamine levels. These data provide the first evidence for a specific link between the constructs of aberrant salience attribution, reduced RPE processing, and potentially increased presynaptic dopamine function.

Reduced default mode network connectivity in schizophrenia patients.

In the present study, we explored possible alterations in the default mode network (DMN) and its functional connectivity in 41 schizophrenia patients and 42 age-matched healthy controls. Schizophrenia patients displayed reduced activation in the ventromedial prefrontal cortex, left superior temporal gyrus including auditory cortex and temporal pole. Psychophysiological interaction analysis revealed reduced connectivity between left superior temporal gyrus including auditory cortex and the left temporal pole in schizophrenia patients compared to healthy subjects.

Altered amygdala activation in schizophrenia patients during emotion processing.

Dysfunctional emotion processing in patients suffering from schizophrenia is a prominent clinical feature of great importance for social functioning and subjective well-being. The neurobiological underpinnings are still poorly understood. Here we investigated a large sample of schizophrenia patients and matched healthy controls with an event-related fMRI task during emotion processing using emotional pictures from the International Affective Picture System (IAPS). Schizophrenia patients revealed stronger right amygdala activation during negative and attenuated response during positive affective picture processing compared to healthy controls. Further analysis indicated that medication status influences activation of the ventral anterior cingulate cortex during negative affective stimuli processing. These results might represent a correlate of altered emotional experience in schizophrenia patients who are known to report less positive and more negative affective states in daily life situations.

Neurobiological correlates of delusion: beyond the salience attribution hypothesis.

Dopamine dysfunction is a mainstay of theories aimed to explain the neurobiological correlates of schizophrenia symptoms, particularly positive symptoms such as delusions and passivity phenomena. Based on studies revealing dopamine dysfunction in addiction research, it has been suggested that phasic or chaotic firing of dopaminergic neurons projecting to the (ventral) striatum attribute salience to otherwise irrelevant stimuli and thus contribute to delusional mood and delusion formation. Indeed, several neuroimaging studies revealed that neuronal encoding of usually irrelevant versus relevant stimuli is blunted in unmedicated schizophrenia patients, suggesting that some stimuli that are irrelevant for healthy controls acquire increased salience for psychotic patients. However, salience attribution per se may not suffice to explain anxieties and feelings of threat that often accompany paranoid ideation. Here, we suggest that beyond ventral striatal dysfunction, dopaminergic dysregulation in limbic areas such as the amygdala in interaction with prefrontal and temporal cortex may contribute to the formation of delusions and negative symptoms. Neuroleptic medication, on the other hand, appears to interfere with anticipation of reward in the ventral striatum and can thus contribute to secondary negative symptoms such as apathy and avolition.