In a clinical context, "red flags" (sometimes referred to as "alarm features") are symptoms or clinical findings that warrant further medical investigation or assessment because they may actually indicate a condition other than the one initially suspected.
Before we begin, let's do a quick recap of some of the characteristics of IBS.
IBS is a Disorder of Gut–Brain Interaction (DGBI). This means that symptoms arise from complex interactions between the gut and the brain.
IBS is diagnosed primarily based on a person's symptoms (using the Rome V criteria) and clinical history. Unlike many structural or inflammatory gastrointestinal diseases, there is usually no structural abnormality or blood test biomarkers that explains the symptoms of IBS.
Although some screening tests may be recommended to rule out or investigate other conditions, such as inflammatory bowel disease (IBD), coeliac disease and microscopic colitis, the investigations required depend on your symptoms and clinical presentation. If you're concerned about your symptoms, it's best to speak with your doctor about whether further testing is appropriate.
IBS itself does not cause gastrointestinal bleeding. Blood in the stool can indicate bleeding somewhere in the gastrointestinal tract and should therefore be medically assessed.
Black, tarry stools can be a sign of bleeding higher up in the gastrointestinal tract, while bright-red blood is more commonly associated with bleeding from the lower gastrointestinal tract, such as the rectum or colon. However, stool colour can have other causes, for example, iron supplements can make stools appear dark.
If you notice unexplained blood in your stool or black, tarry stools, it's important to speak with a healthcare professional to investigate the cause.
Anaemia occurs when the amount of red blood cells in the blood is lower than expected, which affects the amount of oxygen carried around the body. Symptoms can include fatigue, weakness, reduced concentration and shortness of breath.
Iron-deficiency anaemia can occur because of inadequate iron intake, impaired iron absorption or blood loss. Gastrointestinal bleeding and conditions such as coeliac disease can contribute to iron deficiency and anaemia.
Anaemia is not considered a typical feature of IBS. If anaemia is identified in someone with suspected or established IBS, further assessment may be needed to investigate other possible causes, including gastrointestinal blood loss or malabsorption.
Here, we are more concerned about unintentional or unexplained weight loss, particularly when it is persistent or significant. This is different from weight loss that occurs intentionally because of dietary changes or restrictions, such as reducing certain foods because they trigger IBS symptoms.
Some gastrointestinal diseases can cause weight loss because they affect appetite, nutrient absorption or the body's metabolism. Inflammatory or systemic illnesses can also increase energy requirements.
Fever isn't a typical feature of IBS. If you develop a fever alongside gastrointestinal symptoms, this may suggest an infection, inflammatory, or immune condition, or another illness that requires medical assessment.
IBS symptoms can fluctuate in severity and may be unpredictable. However, a persistent in or worsening change in your symptoms, particularly if symptoms are progressively worsening, suggests that a review with your doctor may be needed for further investigations.
IBS symptoms can occur at night, but diarrhoea or other gastrointestinal symptoms that consistently wake you from sleep are less typical of IBS. Nocturnal symptoms may therefore prompt your doctor to investigate other possible causes.
A family history of conditions such as gastrointestinal (bowel/colon) cancer, coeliac disease, IBD or other gastrointestinal conditions may increase a person's risk of developing these conditions. The level of risk varies depending on the condition and the specific family history. Many gastrointestinal conditions, especially in their early or mid stages, can also cause symptoms that overlap with IBS. This is why it's important to tell your GP, physician or gastroenterologist about any relevant family history.
Depending on your symptoms, age, family history and other risk factors, your doctor may recommend investigations such as blood tests, stool tests or endoscopic procedures.
If you're concerned about one or more of these red flags, please let your GP, physician or gastroenterologist know as soon as possible. They can perform a thorough and personalised clinical assessment and determine whether further investigation is needed.
The information provided in this blog is for educational and informational purposes only and is not intended as, nor does it replace, professional medical advice, diagnosis, or treatment. Always seek the advice of your physician, gastroenterologist, or another qualified healthcare provider with any questions you may have regarding a medical condition or dietary changes. If you are experiencing any medical emergency, please dial 000, 119, or your local emergency number, or head to your nearest emergency department immediately.
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