Ulcerative Colitis: Symptoms, Treatment, and Why Early Treatment Changes the Course of the Disease

Ulcerative colitis is a chronic inflammation of the lining of the large intestine. Unlike acute intestinal inflammation—such as that caused by pathogens, which usually subsides after a few days—it does not heal on its own but progresses in flare-ups: periods of severe symptoms alternate with symptom-free periods.

The inflammation almost always begins in the rectum and spreads continuously from there toward the large intestine. If only the rectum is affected, specialists refer to it as proctitis; in cases of extensive involvement, the entire large intestine may be affected (pancolitis). A characteristic feature is the presence of small ulcers—medically known as “ulcers”—in the intestinal mucosa, which give the disease its name: ulcerative colitis literally means “ulcerative inflammation of the large intestine.” In the international medical literature, it is referred to as “ulcerative colitis”; the current study on early treatment initiation refers to the “early treatment of ulcerative colitis.”

Ulcerative colitis, along with Crohn’s disease, is one of the chronic inflammatory bowel diseases, abbreviated as IBD—also referred to as chronic inflammatory bowel diseases in the language of the guidelines. Both conditions result from a misdirected immune response against the body’s own intestines, but differ in the extent and depth of the inflammation. In Germany, an estimated several hundred thousand people live with a diagnosis classified as a chronic inflammatory bowel disease—ulcerative colitis is one of the most common.

To clarify: Ulcerative colitis affects the large intestine. Inflammation of the small intestine usually has other causes, such as infections or food intolerances, and typically presents with watery rather than bloody diarrhea. If symptoms persist, it’s always worth consulting a doctor to determine which section of the intestine is affected.

The exact cause remains unclear to this day. According to the German Society for Gastroenterology, experts believe it results from a combination of several factors:

• A misdirected immune response in which the immune system attacks the body’s own intestinal mucosa
• A genetic predisposition—first-degree relatives have an increased risk
• Changes in the gut microbiota
• Environmental factors such as diet, stress, or previous infections

It is therefore neither a classic infection nor purely a matter of lifestyle. First-degree relatives of people with ulcerative colitis are at increased risk of developing the disease themselves, although this does not allow for a definitive prediction in individual cases.

The role of the gut microbiota

Trillions of bacteria live in the large intestine; every single microorganism in this community contributes to digestion and the body’s defenses. In ulcerative colitis, this balance is often disrupted: the diversity of the gut microbiota is reduced, and protective bacterial strains are less prevalent. Whether this shift is a cause or a consequence of the inflammation is still being researched—what is clear is that the barrier function of the large intestine’s mucosa plays a central role in this process.

In its early stages, ulcerative colitis often presents with symptoms that can easily be confused with other digestive problems:

• Bloody diarrhea, often mixed with mucus
• Frequent, sudden urge to have a bowel movement
• Cramping abdominal pain, usually in the lower left abdomen
• Fatigue and exhaustion
• Unintentional weight loss
• Mild fever during a flare-up

If these symptoms persist for more than two to three weeks, it is advisable to seek medical evaluation. Additional symptoms outside the intestines are possible, as other complaints often affect the joints and skin: joint pain, skin changes, or eye inflammation may occur as accompanying symptoms in some affected individuals. Psychological distress is also a factor—studies describe an increased risk of depressive moods and anxiety disorders in cases with a chronic course.

The diagnosis is generally based on several factors:

• A detailed discussion of symptoms and the course of the disease
• Physical examinations, including palpation of the abdomen
• Blood tests to check for markers of inflammation and anemia
• A stool test for the inflammatory protein calprotectin and for pathogens to rule out an infection
• A colonoscopy, in which an endoscope visualizes the inside of the large intestine

During the initial diagnosis, a tissue sample is also taken from the intestinal mucosa and examined histologically. Only by considering these findings together is it possible to reliably diagnose the disease and distinguish it from other intestinal disorders.

Ulcerative colitis and Crohn’s disease are often confused—both are forms of IBD, but they differ significantly:

• Ulcerative colitis affects only the large intestine, and the inflammation spreads in a continuous pattern
• Crohn’s disease can affect the entire digestive tract, often in isolated, non-contiguous segments
• In ulcerative colitis, usually only the outermost layer of the mucosa is inflamed; in Crohn’s disease, all layers of the intestinal wall can be affected

Unlike Crohn’s disease, ulcerative colitis can generally be cured by completely removing the large intestine. Whether a patient has Crohn’s disease or ulcerative colitis therefore directly influences treatment—sometimes a definitive diagnosis can only be made as the disease progresses.

This is precisely where a recent study comes in: It shows that patients treated with biologics early in the course of the disease are less likely to develop a progressive, complicated course than those who receive these medications later.

Biologics are genetically engineered active ingredients that specifically target the overactive immune response, rather than—like older medications—suppressing the entire immune system. Among the established treatments is the TNF inhibitor infliximab. Early use could therefore not only control acute flare-ups more quickly but also prevent long-term damage to the intestinal mucosa.

Important for those affected: The study findings are encouraging, but they do not replace an individual medical evaluation. Whether early biologic therapy is an option depends on the severity and extent of the inflammation, as well as other factors. The goal of therapy is to achieve remission—that is, a symptom-free phase—as quickly as possible and to maintain it long-term.

Drug therapy is tailored to the severity and course of the disease. Common treatment options include:

• 5-aminosalicylates (5-ASA), such as mesalazine: reduce inflammation in the mucous membrane; often the first choice for mild to moderate cases—administered as suppositories, foam, or tablets, depending on the extent of the condition
• Corticosteroids (cortisone): effective during acute flare-ups; due to their side effects, steroids are not suitable for long-term therapy
• Immunosuppressants: Active ingredients such as azathioprine broadly suppress the immune system and are used in cases of moderate disease; in severe flare-ups, cyclosporine can stabilize the condition in the short term
• Biologics and JAK inhibitors: Targeted antibody therapies as well as small molecules such as tofacitinib, increasingly used early in the course of the disease
• Surgical treatment (colectomy): In severe, treatment-resistant cases, the large intestine is surgically removed—depending on the procedure, either with a colostomy or with a pouch that replaces the removed rectum as a reservoir. More on surgery for ulcerative colitis

Pain relievers should be chosen with care: Conventional anti-inflammatory pain relievers (NSAIDs) can trigger flare-ups. Antibiotics, too, are used only selectively for specific complications, not routinely. Both should be discussed with the treating physician.

There is no specific diet for ulcerative colitis—tolerance varies greatly from person to person. However, during an acute flare-up, many people report recurring patterns:

• Easily digestible, low-fiber foods are often better tolerated
• Several small meals instead of a few large portions
• Drink enough fluids to compensate for fluid loss due to diarrhea
• Raw foods, very fatty foods, and foods that cause significant gas are often less well tolerated
• Sugar substitutes such as sorbitol can worsen diarrhea

During the remission phase, a normal, balanced diet is usually possible. It is important to avoid unintentional weight loss and malnutrition: blood loss and reduced nutrient absorption can lead to iron, vitamin B12, or zinc deficiencies. Consultation with a nutritional medicine specialist helps identify individual intolerances without unnecessarily restricting the diet.

Studies show that nonsmokers and former smokers develop the disease slightly more often than current smokers, and that smoking may slightly improve the course of the disease in some patients. This does not in any way mean that smoking is recommended: the risks to the heart, lungs, and cancer far outweigh this potential benefit. Above all, this association highlights just how complex the immune system’s response is in this disease.

A single flare-up often lasts several weeks, depending on its severity and treatment. With appropriate treatment, the disease can be well controlled in most patients, and life expectancy is generally not significantly reduced. Ulcerative colitis is therefore usually not fatal, but it can lead to serious complications if left untreated.

A rare but dangerous complication is toxic megacolon, an acute, severe dilation of the large intestine. Typical warning signs:

• Severe abdominal pain, usually with a sudden onset
• A distended, tender abdomen
• High fever
• Rapid heartbeat and circulatory problems
• Decreased or absent bowel movements despite an acute flare-up

This is a life-threatening emergency that requires immediate medical attention. In addition, long-term, extensive disease increases the risk of colorectal cancer. For this reason, regular screening colonoscopies are recommended once the disease has been present for about eight years.

There is no way to prevent the disease itself. However, it is certainly possible to extend the time between flare-ups:

• Take maintenance therapy consistently, even during symptom-free periods
• Attend follow-up appointments and undergo screening exams
• Avoid triggers such as NSAID pain relievers and gastrointestinal infections
• Reduce stress—stress is considered a potential trigger for relapses
• Check your vaccination status, especially before starting immunosuppressive treatment

For many people living with this condition, life with the disease means, above all, regaining the ability to plan ahead with confidence. A support group can help you share practical experiences—from finding restrooms while out and about to dealing with your employer and health insurance provider.

You should seek medical advice if you experience:

• Bloody or mucus-containing stools lasting several days
• Persistent diarrhea with abdominal pain
• Fever combined with digestive symptoms
• A sudden worsening of symptoms during a known flare-up

Patients can find specialized care in gastroenterology, the medical specialty that deals with diseases of the digestive tract. In cases of severe or treatment-resistant disease, surgery is discussed in collaboration with a surgical department.

Ulcerative colitis is highly treatable when therapy is tailored to the individual’s course of the disease. The new study results on early biologic therapy offer hope that severe, progressive cases can be prevented more frequently in the future and that more patients will achieve long-term, stable remission. Anyone who has just been diagnosed with inflammatory bowel disease should openly discuss the causes of ulcerative colitis, its treatment, and the long-term risk of colorectal cancer with their treating physician.