Many people are alarmed when they hear the term „occult blood” and immediately assume the worst. Whilst it can indeed indicate a more serious problem, it is important to know that there can be numerous causes, and early detection is key to successful treatment. But what exactly is occult bleeding, what symptoms might indicate it, and most importantly: what should you do if you suspect you have it? In this article, we explore the topic in depth so that you can feel confident in understanding the issue and take the necessary steps to protect your health.
What is occult bleeding?
Occult bleeding, also known as hidden bleeding, is bleeding originating from the digestive system that is not visible to the naked eye in the stools. The amount is so small that it can only be detected by specialised laboratory tests, such as a faecal occult blood test. The blood may originate from any part of the digestive tract, from the oesophagus right down to the rectum. The location of the source of the bleeding influences the appearance of the blood in the stools: in the case of upper gastrointestinal (stomach, oesophagus), the blood is digested, which may result in black, tarry stools (melaena), whilst bleeding from the lower sections (large intestine, rectum) tends to appear as fresh, red blood (haematochezia). In the case of occult bleeding, however, the colour and consistency of the stools may appear completely normal.
What symptoms might indicate hidden bleeding?
As the blood loss is minimal and chronic, occult bleeding often remains completely asymptomatic for a long time. The most common sign that draws attention to the condition is iron-deficiency anaemia of unknown origin. If you experience any of the following symptoms, you should definitely consult a doctor to investigate the underlying causes:
- Constant tiredness and weakness: Iron deficiency prevents the body from producing sufficient haemoglobin, which is responsible for transporting oxygen. A lack of haemoglobin can lead to general weakness and reduced physical and mental performance.
- Paleness: Pallor of the skin, lips and nail beds is also a classic sign of anaemia.
- Dizziness, shortness of breath: In cases of more severe anaemia, shortness of breath or dizziness may occur even with minimal exertion.
- Abdominal discomfort or pain: Although they do not always occur, abdominal pain, bloating or cramps may also indicate a problem with the digestive system.
- Changed bowel movements: Persistent constipation or diarrhoea can also be a warning sign.
- Weight loss of unknown cause: If you are not on a diet but are still losing weight, you should definitely seek medical advice.
It is important to emphasise that these symptoms are non-specific and can be caused by a number of other conditions. However, if the symptoms persist, and particularly if you have been diagnosed with iron-deficiency anaemia, the possibility of hidden bleeding should definitely be considered.
What can cause hidden bleeding?
Hidden bleeding may be caused by a number of conditions of varying severity. These can be categorised according to the source of the bleeding into the upper and lower gastrointestinal tracts.
Causes relating to the upper gastrointestinal tract (oesophagus, stomach, duodenum)
- Stomach and duodenal ulcers (peptic ulcers): Ulcers are lesions of the mucous membrane, often caused by the bacterium _Helicobacter pylori_ or certain medicines (e.g. non-steroidal anti-inflammatory drugs, NSAIDs). These ulcers may bleed.
- Gastritis and oesophagitis: Inflamed mucous membranes are more fragile and more prone to bleeding.
- Oesophageal varices: In cases of severe liver disease (e.g. cirrhosis), varicose veins may develop in the oesophagus; if these rupture, they can cause severe bleeding, although minor, oozing bleeding may also occur.
- Vascular tumours (angiodysplasia): Small, abnormal growths located beneath the mucous membrane that bleed easily.
- Tumours: Benign and malignant tumours of the oesophagus and stomach can also cause bleeding.
Causes relating to the lower gastrointestinal tract (small bowel, large bowel, rectum)
- Colon polyps: Small growths on the intestinal wall, some of which may become malignant over time (colon cancer). The surface of polyps is fragile, which can lead to oozing bleeding. This is one of the most common and most significant causes of occult bleeding.
- Colorectal cancer: Malignant tumours arising from polyps often cause occult bleeding. A positive result for blood in the stool may be one of the earliest signs of the disease.
- Inflammatory bowel diseases (IBD): Crohn’s disease and ulcerative colitis are characterised by chronic inflammation, which causes the intestinal wall to bleed.
- Diverticula: Small pouches (diverticula) that form in the wall of the large bowel, which can become inflamed (diverticulitis) and bleed.
- Hemorrhoids (nodus haemorrhoidalis): Although haemorrhoids are usually associated with fresh, red bleeding, which can be seen on toilet paper or on the surface of the stool, in some cases they may also cause minor, hidden bleeding.
- Tumours or ulcers of the small intestine: Although less common, lesions in the small intestine – such as tumours or ulcers caused by medication – may also be the source of the bleeding.
Diagnosing occult bleeding: what should I do?
If you suspect hidden bleeding based on the symptoms listed above, the first and most important step is to consult your GP or a specialist gastroenterologist. Do not delay getting checked! Early diagnosis significantly improves the chances of successful treatment, particularly in the case of cancer. The Endomedix Gastroenterology Centre Our specialists, equipped with modern diagnostic tools and a wealth of experience, are on hand to identify the causes of hidden bleeding.
The steps involved in the investigation are as follows:
- Faecal occult blood test: As a first step, the doctor will usually request a stool test. There are two main types: the guaiac-based test (gFOBT) and the more modern, more specific immunochemical test (FIT). The FIT test specifically detects human haemoglobin, so it is not affected by food consumed (e.g. red meat) and is more sensitive to bleeding from the large bowel.
- Laboratory tests: A complete blood count is essential for confirming or ruling out iron-deficiency anaemia.
- Endoscopic examinations: In the event of a positive faecal occult blood test or unexplained anaemia, the next essential step is an endoscopic examination, which allows the gastroenterologist to directly examine the mucous membranes of the digestive tract.
- Colonoscopy (colonoscopy of the colon): This is the „gold standard” for detecting abnormalities in the large bowel, particularly polyps and tumours. During the examination, a flexible instrument (a colonoscope) is inserted through the anus and guided along the entire length of the large bowel. Not only can the source of any bleeding be identified during the examination, but any polyps found can be removed immediately (polypectomy), and a tissue sample (biopsy) can also be taken from suspicious areas. Many people are apprehensive about this examination, but it is important to know that it can now be carried out under general anaesthesia, making it completely painless. The Endomedix Gastroenterology Centre It places great emphasis on patients’ comfort and enables pain-free examinations.
- Gastroscopy (gastroscopy of the stomach): If a colonoscopy fails to identify the source of the bleeding, or if the symptoms suggest the bleeding originates in the upper gastrointestinal tract, a gastroscopy is required. In this case, a thin, flexible instrument is passed through the mouth into the oesophagus, stomach and duodenum.
- Capsule endoscopy: If gastroscopy and colonoscopy fail to reveal anything, but occult bleeding persists, an examination of the small intestine is required. During capsule endoscopy, the patient swallows a small capsule fitted with a camera, which travels through the entire digestive tract and takes images of the small intestine – an area that is difficult to reach with conventional endoscopes.
Treatment of occult bleeding
Treatment always depends on the underlying cause. Once the gastroenterologist has identified the source of the bleeding, targeted treatment can begin:
- Removal of polyps: Removing polyps during a colonoscopy eliminates both the source of the bleeding and a potential precancerous condition.
- Medication: In the event of an ulcer or inflammation, your doctor may prescribe acid-reducing medication, anti-inflammatory drugs, or a course of antibiotics to eradicate _Helicobacter pylori_.
- Endoscopic haemostasis: In the event of an active source of bleeding (e.g. an ulcer, angiodysplasia), the bleeding can be stopped immediately during the endoscopic examination using various techniques (e.g. clip application, electrocoagulation).
- Surgery: In the case of a malignant tumour or another lesion that cannot be treated endoscopically, surgery may be required.
- Iron supplementation: To treat anaemia, the doctor prescribes oral iron supplements or, in more severe cases, intravenous iron replacement therapy.
The importance of prevention
Hidden bleeding and the often serious underlying conditions, such as bowel cancer, can be prevented or detected at an early stage. Regular bowel cancer screening is recommended for people aged 50 and over (and, according to some guidelines, from the age of 45), even if they have no symptoms. The simplest way to do this is through an annual faecal occult blood test, followed by a colonoscopy if the result is positive. In cases of a family history of the disease, screening should begin earlier.
A Guide to Recovery
Hidden blood in the stools is a warning sign that should not be ignored. Whilst it is understandable to be apprehensive about undergoing tests, modern medicine now offers gentle and painless procedures. Early detection can save lives.
If you are suffering from iron-deficiency anaemia or are experiencing the symptoms described above, don’t delay! Book an appointment at a reputable gastroenterology centre. The Endomedix Gastroenterology Centre Its experienced doctors and empathetic staff will help you to reach a diagnosis and choose the right treatment, so that you can regain your health and peace of mind as soon as possible.
