Asymptomatic brain lesions on cranial magnetic resonance imaging in inflammatory bowel disease

Sensorineural hearing loss and ulcerative colitis in remission

INTRODUCTION

Sensorineural hearing loss (SNHL) has been reported in association with inflammatory bowel disease (IBD). However, SNHL as an extraintestinal manifestation of IBD is frequently underreported. In the present study, we compared the prevalence and severity of SNHL among patients with IBD-ulcerative colitis (IBD-UC) in remission with controls to find out any association between SNHL and IBD-UC in remission compared to controls.

METHODS

This single-center hospital-based prospective observational study included outdoor patients with IBD-UC in remission and healthy age- and sex-matched controls. Eligible patients and healthy participants were subjected to a battery of audiological tests (otoscopy, tympanometry and pure tone audiometry [PTN]) after thorough systemic and ear, nose and throat (ENT) examination.

RESULTS

A total of 100 patients were enrolled in the study: 50 in IBD-UC in the remission group and 50 in the control group. None of the demographic variables (age, gender, residence and habits) were significantly different between the two groups. Otoscopy and tympanometry were normal in all patients and controls. The difference between the two groups in respect to frequency and severity of SNHL on PTA and in respect to unilateral and bilateral distribution of the hearing loss was not statistically significant.

CONCLUSION

There is no statistically significant difference in frequency and severity of SNHL between patients with ulcerative colitis in remission and healthy age- and sex-matched controls.

Radiologically isolated syndrome is antiquated amidst evolving McDonald criteria for multiple sclerosis

The diagnosis of radiologically isolated syndrome (RIS) is untenable in the modern era as new diagnostic criteria for multiple sclerosis (MS) continue to evolve. Even without optic nerve involvement, the shift in the diagnostic criteria for MS forces clinicians to make a diagnosis at the earliest possible time and appropriate treatment initiated. In this analysis, we revisit the original RIS criteria as published and conclude that RIS as a diagnostic entity is obsolete.

Exploring joint patterns of brain structure and function in inflammatory bowel diseases using multimodal data fusion

BACKGROUND

A growing number of neuroimaging studies suggest distinct neural changes in inflammatory bowel diseases (IBDs). Whether such changes may show similar spatial patterns across distinct neural features within and between specific IBD is unclear. To address this question, we used multivariate multimodal data fusion analysis to investigate structure/function modulation in remitted patients with Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

Patients with IBD (n = 46; n = 31 with CD, n = 15 with UC) in stable remission and 17 healthy controls (HC) underwent structural magnetic resonance imaging (sMRI) and resting-state functional magnetic resonance imaging (rs-fMRI) as well as cognitive testing. Anxiety, depression, and fatigue were assessed using self-rating questionnaires. sMRI data were analyzed via voxel-based morphometry (VBM) and rs-fMRI data via amplitude of low-frequency fluctuations (ALFFs) and regional homogeneity (ReHo). Detection of cross-information between VBM, ALFF, and ReHo was conducted by means of a joint independent component analysis (jICA), followed by group-inference statistics.

KEY RESULTS

Joint independent component analysis detected structural alterations in middle frontal and temporal regions (VBM), and functional changes in the superior frontal gyrus (ReHo) and the medial as well as inferior frontal, inferior temporal, rectal, and subcallosal gyrus (ALFF). One joint component of extracted features of the three modalities differed significantly between IBD patients and controls (p = 0.03), and most distinctly between HC and patients with UC.

CONCLUSIONS AND INFERENCES

Using a multivariate data fusion technique, this study provides further evidence to brain alterations in IBD. The data suggest distinct neural differences between CD and UC, particularly in frontotemporal regions.

Aberrant brain structural large-scale connectome in Crohn's disease

BACKGROUND

Disturbed brain-gut interactions and a bidirectional relationship between inflammation and psychiatric symptoms such as anxiety and depression are being discussed in patients with inflammatory bowel diseases (IBD). Alterations of brain structure and function in IBD have been reported with heterogeneous results. Whether these changes reflect independent localized deficits or rather a systematic disruption in the anatomical organization of large-scale brain networks remains unclear. The present study investigated the gray matter structural connectome in patients with Crohn's disease (CD).

METHODS

Sixty participants (30 with quiescent CD and 30 matched healthy controls [HC]) underwent high-resolution brain MRI at 3 Tesla. Well-established graph theoretical metrics were analyzed at the global and regional network level and compared between groups.

KEY RESULTS

The networks in both groups followed a small-world organization, that is, an architecture that is simultaneously highly segregated and integrated. However, transitivity, a measure of global network segregation, was significantly reduced in patients (P = 0.003). Regionally, patients showed a reduction of nodal betweenness centrality in the right insula and cuneus and the left superior frontal cortex and reduced nodal degree within the left-hemispheric cingulate and the left lateral and right medial orbitofrontal cortex.

CONCLUSION AND INFERENCES

These findings lend support to the hypothesis that CD is accompanied by alterations in both global network organization and regional connectivity. A deeper understanding of neural central networks in IBD may facilitate the development of complementary strategies in the treatment of "extraintestinal" comorbid conditions such as depression or anxiety.

Mitochondrial neurogastrointestinal encephalopathy: a clinicopathological mimic of Crohn's disease

Background

Mitochondrial neurogastrointestinal encephalopathy (MNGIE), due to mutations in TYMP, often presents with gastrointestinal symptoms. Two sisters, initially managed for Crohn’s disease based upon clinical, imaging and pathological findings, were later found to have MNGIE. The cases provide novel clinicopathological insight, for two further reasons: both sisters remain ambulant and in employment in their late 20s and 30s; diagnosis in one sister was made after a suspected azathioprine-precipitated acute illness.

Case presentation

A 25-year-old female presented with diarrhoea, vomiting, abdominal pain, and bloating. Faecal calprotectin, colonic biopsies and magnetic resonance enterography were consistent with a diagnosis of Crohn’s disease. Azathioprine initiation preceded admission with a sore throat, headache, myalgia, and pyrexia. Withdrawal led to rapid clinical improvement. MRI brain revealed persistent, extensive white matter changes. Elevated plasma and urine thymidine and deoxyuridine, and genetic testing for TYMP variants, confirmed MNGIE. Testing of the patient’s sister, also diagnosed with Crohn’s disease, revealed identical variants. In this context, retrospective review of colonic biopsies identified histological findings suggestive of MNGIE.

Conclusions

Azathioprine interference in nucleic acid metabolism may interact with the mitochondrial DNA depletion of MNGIE. Nucleotide supplementation, proposed for treatment by manipulating mitochondrial nucleoside pools, may require caution. The late onset and mild phenotype observed confirms presentation can occur later in life, and may reflect residual thymidine phosphorylase activity. Clinicians should consider measuring plasma thymidine levels in suspected Crohn’s disease to rule out MNGIE, particularly if white matter abnormalities are identified on neuroimaging.

Structural brain lesions in inflammatory bowel disease

Central nervous system (CNS) complications or manifestations of inflammatory bowel disease deserve particular attention because symptomatic conditions can require early diagnosis and treatment, whereas unexplained manifestations might be linked with pathogenic mechanisms. This review focuses on both symptomatic and asymptomatic brain lesions detectable on imaging studies, as well as their frequency and potential mechanisms. A direct causal relationship between inflammatory bowel disease (IBD) and asymptomatic structural brain changes has not been demonstrated, but several possible explanations, including vasculitis, thromboembolism and malnutrition, have been proposed. IBD is associated with a tendency for thromboembolisms; therefore, cerebrovascular thromboembolism represents the most frequent and grave CNS complication. Vasculitis, demyelinating conditions and CNS infections are among the other CNS manifestations of the disease. Biological agents also represent a risk factor, particularly for demyelination. Identification of the nature and potential mechanisms of brain lesions detectable on imaging studies would shed further light on the disease process and could improve patient care through early diagnosis and treatment.

Psychiatric comorbidity in the treatment of patients with inflammatory bowel disease

Ulcerative colitis and Crohn’s disease, commonly known as inflammatory bowel disease (IBD), draw attention from specialists of various disorders, including gastroenterology, psychiatry, and radiology. The involvement of a cortical influence in the brain-gut axis as well as the interaction of the hypothalamic-pituitary-adrenal axis and the peripheral nervous system provide an initial explanation of the psychological symptoms associated with IBD. The involvement of structures the limbic system, such as the anterior cingulate cortex, the prefrontal cortex, and the amygdala, paves the way for the discovery of the mechanisms underlying depression depression, anxiety, alexithymia, personality traits, and other psychological impairments following the onset of IBD. Psychiatric therapy in IBD patients is almost as important as the gastroenterological approach and consists of pharmacological treatment and psychotherapy. Neither of the available psychiatric treatment methods is considered the golden standard because both methods have side effects, and psychotropic medication can provoke the worsening of IBD symptoms. Thus, both approaches must be applied with awareness of the possibility of side effects. We suggest that psychiatrists and gastroenterologists work together to reach a consensus on IBD therapy to ensure success and to reduce side effects and relapse to the lowest possible rates.

Inflammatory bowel disease: An increased risk factor for neurologic complications

Only a very few systematic studies have investigated the frequency of neurologic disorders in patients with Crohn’s disease (CD) and ulcerative colitis (UC), which are the two main types of inflammatory bowel disease (IBD). Results have been inconsistent and variable, owing to differences in case-finding methods and evaluated outcomes in different studies. The most frequent neurologic manifestations reported in CD and UC populations are cerebrovascular disease (with either arterial or venous events), demyelinating central nervous system disease, and peripheral neuropathy (whether axonal or demyelinating); however, the literature describes numerous nervous system disorders as being associated with IBD. The pathogenesis of nervous system tissue involvement in IBD has yet to be elucidated, although it seems to be related to immune mechanisms or prothrombotic states. The recently-introduced tumor necrosis factor (TNF) inhibitors have proven successful in controlling moderate to severe IBD activity. However, severe neurologic disorders associated with TNF inhibitors have been reported, which therefore raises concerns regarding the effect of anti-TNF-α antibodies on the nervous system. Although neurological involvement associated with IBD is rarely reported, gastroenterologists should be aware of the neurologic manifestations of IBD in order to provide early treatment, which is crucial for preventing major neurologic morbidity.