11 March 2019 Although it may affect any part of the digestive tract, from the mouth to the anus, it is usually located in the final segment of the small intestine (ileum) and the large intestine . The inflammation can affect all layers of the digestive wall and ulcers may form. It may also not be continuous with inflamed areas alternating with healthy areas. When does Crohn's disease appear? In Crohn's disease, periods of active disease alternate with periods with no symptoms, which may last months or even years. It is impossible to predict any of these phases or how long they will last. Periods of remission may be: The result of treatment with medication; The result of a surgical procedure; Spontaneous (very rarely). The inflammation in new episodes of the disease may occur in the same place or close to previous ones, though it can also affect other areas . Who can develop Crohn's disease? Although it can affect people of any age, in most cases Crohn's disease is diagnosed in young adults. Its incidence is similar in men and women. It is higher in smokers and there may be a genetic predisposition. What causes Crohn's disease? The cause of Crohn's disease is not known . However, the possible causes may be: Alterations in the immune system; Infection by an unknown micro-organism; A reaction to certain foods. Changes in the immune system are common in people with Crohn's disease. Although it is not completely clear whether they are a cause or consequence of the disease, it is more likely that it is caused by dysfunctions plus environmental effects. Crohn's disease is considered an autoimmune disease. Regardless of its cause, in Crohn's disease the organism produces an incorrect, excessive reaction in the form of a chronic inflammatory process. This reaction is due to food or other compounds in the digestive tract that are harmless but not recognised as such. What are the symptoms of Crohn's disease? Given that Crohn's disease can affect any part of the digestive tract , the symptoms vary and are related to the location of the disease. The most common are: Diarrhoea; Abdominal pain; Fever; Loss of appetite; Weight loss. Nonetheless, because of the possible common complications of Crohn's disease in the digestive system (stenosis, fistulas, abscesses, anal fissures) and other locations, there may be other symptoms , such as: Constipation; Fatigue; Anal pain; Rectal bleeding; Symptoms of a bowel obstruction; Bloody stools; Nutritional deficiencies; Joint pain; Skin lesions; Symptoms of kidney stones and gallstones; Alterations in the eyes; Among others. Children with Crohn's disease may also show signs of retarded growth . Symptoms and their severity may vary in successive episodes of the disease. How is Crohn's disease diagnosed? Crohn's disease is diagnosed on the basis of: Clinical history; Symptoms; Examination of the patient; Any other necessary exams or tests. These may include: Blood tests, which may suggest the existence of an inflammation; Stool analysis, which may reveal blood loss; X-rays with contrast to locate inflammation, ulcers or stenoses and help assess their severity; A colonoscopy to view the interior of the colon, determine the distribution and severity of lesions and inflammation, detect possible complications and collect samples to confirm the diagnosis. More recently, video capsule endoscopy has been used in the diagnosis of Crohn's disease. How is Crohn's disease treated? There is no cure for Crohn's disease. The aim is therefore to improve the quality of life of patients by treating the symptoms and attempting to prolong symptom-free periods. Treatment of Crohn's disease varies on the basis of: The location and severity of the lesions; The existence of complications (fistulas, stenoses, obstructions, etc); Extra-intestinal manifestations; Response to previous treatments. In milder cases and during remission periods, no treatment may actually be necessary. As a rule, Crohn's disease is treated with medication . We therefore endeavour to combat the symptoms and prevent any side effects of long-term treatments. If medication is not effective in more advanced or severe cases of the disease and especially if there are complications, it may be necessary to perform surgery. If the disease is located in the bowel, surgery may involve removing the affected parts and joining the healthy ends. If this join is not possible, the healthy end of the bowel will be connected to an opening in the abdominal wall (ostomy) to remove stools. Around 75% of people with Crohn's disease are estimated to need surgery at some stage of the disease. In most cases, surgical procedures are needed to resolve complications , however. This is because the possible location of Crohn's disease in the digestive tract and the fact lesions from subsequent episodes are not always in the same place mean surgical treatment may not offer a cure. Although surgery significantly improves the quality of life of patients and is normally associated with a log period of remission, in most cases they experience episodes of the disease after some time. Gastroenterologists and general surgeons can help treat this disease. Are there any preventive measures for someone suffering from Crohn's disease? There are no direct effects of diet on the inflammation associated with Crohn's disease. Some measures are normally taken in terms of diet, however , in order to help control the symptoms. A low-fibre diet is normally recommended or even a liquid diet for more severe cases. It may also be necessary to take mineral, vitamin or other nutrient supplements , if there are absorption problems. This article was written with the support of physicians from the Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
