Cerebral sinus thrombosis in ulcerative colitis

Neurology of inflammatory bowel disease

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions affecting the digestive system, comprising two main distinctive entities, ulcerative colitis (UC) and Crohn's disease (CD). Besides gastrointestinal manifestations, IBD causes extraintestinal manifestations in the central and peripheral nervous system. The incidence of neurological complications in IBD ranges from 0.25% to 47.5%. The pathophysiology of neurological manifestations of IBD is mostly immune mediated, but dysfunction of the brain-gut axis, arterial and venous thromboembolism, infections, nutritional deficiencies and side-effects of medications (steroids, metronidazole, sulfasalazine, anti-TNF-α, anti-integrin antibodies) are other contributory mechanisms. Patients with IBD have an increased risk of arterial and venous stroke, mainly during periods of exacerbations. Vasculitis is extremely rare. There is a bidirectional association between multiple sclerosis and IBD, with a relative risk for comorbidity of 1.54, being 1.53 for the risk of multiple sclerosis in IBD and 1.55 for the risk of IBD in multiple sclerosis patients. Anti-TNF-α therapy is contraindicated in the treatment of patients who have both IBD and multiple sclerosis. Demyelinating disorders can also be a rare complication of anti-TNF-α therapy. Optic neuritis, transverse myelitis, progressive myelopathy, central nervous system infections, epilepsy and encephalopathy are among other uncommon neurological complications. Peripheral nervous system manifestations include peripheral neuropathy, either demyelination and axonal, myasthenia gravis and polymyositis/dermatomyositis and localized forms of myositis.

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.

Neurologic manifestations of gastrointestinal and liver diseases

Hepatic and gastrointestinal disorders can produce a wide spectrum of neurologic complications both affecting the central nervous system (CNS) and the peripheral nervous system. These manifestations range in severity from coma in acute liver failure and acute pancreatitis, to minor cognitive changes in chronic portosystemic encephalopathy and hepatitis C. Cerebrovascular diseases can complicate hepatitis C infection and inflammatory bowel disease. Demyelinating disorders may co-exist with inflammatory bowel disease. Anti-tumor necrosis factor alpha drugs may induce demyelination. Ataxia may occur in malabsorption syndromes and in gluten related disorders. Characteristic movement disorders are key features of acquired hepatocerebral degeneration and of Whipple disease. Multiple types of neuropathy can be found in association with hepatitis, inflammatory bowel disease and gluten related disorders.

Neurologic manifestations of inflammatory bowel diseases

Inflammatory bowel diseases (IBD) are chronic, relapsing and remitting inflammatory conditions affecting the digestive system, comprising two main distinctive diseases, ulcerative colitis (UC) and Crohn's disease (CD). Besides the classic gastrointestinal manifestations, a variable number of IBD patients present with extraintestinal manifestations, including central and peripheral nervous system involvement. Peripheral neuropathy is one of the most common complications. An inflammatory myopathy has also been found. Cranial neuropathies include the Melkersson-Rosenthal syndrome, optic neuritis, and sensorineural hearing loss. Patients with IBD have a remarkable thromboembolic tendency and are at increased risk of both venous and arterial thrombotic complications. The prothrombotic state in IBD has multiple contributors. Ischemic stroke occurs through several mechanisms, including large artery disease, small vessel disease, paradoxical embolism, endocarditis, vasculitis, and associated with anti-TNF-α therapy. Thrombosis of the dural sinus and cerebral veins are at least as frequent as arterial stroke in IBD. Multiple sclerosis has been repeatedly associated with IBD. Up to 50% of IBD present asymptomatic white matter lesions. Other central nervous system complications include a slowly progressive myelopathy, epidural and subdural spinal empyema secondary to fistulous extension from the rectum, seizures, and encephalopathy.