Brief overview
- Symptoms: During an attack, the eyes and possibly the skin turn yellow, and sometimes symptoms such as headaches, abdominal pain, tiredness and loss of appetite occur.
- Treatment: Treatment or a special diet are not normally necessary, but abstaining from alcohol and nicotine is helpful.
- Causes: Meulengracht’s disease is caused by changes in the genetic material that reduce the activity of an enzyme required for the breakdown of red blood pigment.
- Risk factors: Factors that favor an attack include infections, fasting, alcohol and nicotine, a low-fat diet, certain medications and physical exertion.
- Diagnosis: A blood test reveals elevated bilirubin levels. In addition, a fasting or nicotinic acid test leads to an increase in the bilirubin level.
- Course of the disease: The disease is harmless, the symptoms often occur in episodes and usually become less frequent with age.
- Prevention: As the metabolic disorder is genetic, it is not possible to prevent it, but the symptoms can be alleviated or avoided by avoiding the risk factors.
What is Meulengracht’s disease?
Haemoglobin is found in red blood cells (erythrocytes). After a lifespan of around 120 days, these are sorted out by the body and broken down to make room for fresh blood cells. During this process, the haemoglobin is released and broken down in the spleen, liver and bone marrow.
The organism first converts it into bilirubin, which is not soluble in water. In this form, it reaches the liver. There is an enzyme there, known as UDP-glucuronosyltransferase, which makes the bilirubin water-soluble.
The water-soluble bilirubin then enters the intestine with the bile, which is responsible for the yellowish color. There it is further converted to dark brown stercobilin and finally excreted in the stool. A certain proportion of the bilirubin (around 20 percent) is absorbed back into the body by the intestine and a small proportion is excreted by the kidneys. This is why the urine is yellow in color.
Hemoglobin breakdown in Meulengracht’s disease
In Meulengracht’s disease, the UDP-glucuronosyltransferase is less functional and only performs about 30 percent of the normal degradation work. As a result, the concentration of non-water-soluble bilirubin in the blood increases. In this case, doctors speak of hyperbilirubinemia.
In Meulengracht’s disease, the liver is not damaged. Only the enzyme activity in the organ is reduced. The amount of bilirubin produced poses no danger to the body. In some other metabolic diseases, such as Crigler-Najjar syndrome, the situation is different: in this case, UDP-glucuronosyltransferase is almost completely absent. The concentration of water-insoluble bilirubin then rises so sharply that the consequences can be serious.
Who is affected by Meulengracht’s disease?
Around nine percent of the population have this metabolic disorder. Men are more likely to suffer from Meulengracht’s disease, and white-skinned people are more frequently affected than dark-skinned people.
What are the symptoms of Meulengracht’s disease?
The main symptom of Meulengracht’s disease is a yellowing of the part of the eyeball that otherwise appears white (so-called sclera). In rare cases, the skin also turns yellow. Unlike many liver or biliary diseases, however, there is no itching. The symptoms usually only appear after puberty and are often the first and only sign of Meulengracht’s disease.
- Tiredness, exhaustion, fatigue
- Headaches and even migraine attacks
- Abdominal pain and nausea
- Loss of appetite
- Upset moods
The extent of the symptoms does not correlate with the level of bilirubin.
What to do with Meulengracht’s disease?
As Meulengracht’s disease does not cause any symptoms in many cases and does not pose a serious risk to health, treatment is usually not necessary. With a few rules of conduct, it is also possible for those affected to keep the bilirubin content in the blood low.
Meulengracht’s disease: diet
It is generally advisable for people with Meulengracht’s disease to eat a normal, balanced diet.
Prolonged periods of hunger, for example during fasting, lead to an increase in bilirubin in the blood. Low-fat food also causes the bilirubin content in the blood to rise. If the skin and eyes turn yellow during a diet, this is not normally a cause for concern as the metabolic disorder is not a disease.
Two stimulants also increase the bilirubin content in Meulengracht’s disease: alcohol and nicotine. It is therefore advisable for people who find the yellowing of their skin and eyes disturbing to avoid both.
Appropriate dietary supplements only make sense if there is actually a vitamin D deficiency. As an oversupply of vitamin D is associated with health risks, those affected should definitely have a doctor check whether they really need it. The costs of such a test are normally covered by statutory health insurance.
Alternative medicine and home remedies for Meulengracht’s disease
It is not known whether alternative medicine or naturopathic methods have a positive effect on the metabolic disorder. If physical symptoms occur with Meulengracht’s disease, appropriate procedures may be able to provide relief. These include, for example, relaxation techniques for headaches or herbal teas such as fennel, camomile or peppermint tea for abdominal pain. Simple household remedies such as a hot-water bottle can also sometimes provide good relief.
Home remedies have their limits. If the symptoms persist over a longer period of time and do not improve or even get worse, you should always consult a doctor.
Cause and risk factors
Certain factors increase the bilirubin content in the blood and therefore intensify the symptoms of Meulengracht’s disease. The factors that may trigger such an attack include
- infections
- fasting
- Alcohol consumption
- Nicotine consumption (smoking)
- Very low-fat diet
- Certain medications
- Major sporting exertion
The reason why sporting activities increase the symptoms is a certain muscle protein: myoglobin, which has similar properties to haemoglobin. It supplies the muscles with oxygen and is broken down in the same way as haemoglobin. Accordingly, the bilirubin level rises with increased muscle strain.
There is no clear answer as to how long an episode of Meulengracht’s disease lasts. However, it is helpful to avoid the risk factors in order to reduce the bilirubin level – and thus the symptoms.
UDP-glucuronosyltransferase and the effect of medication
There are also drugs that further reduce the activity of UDP-glucuronosyltransferase. So-called protease inhibitors, which doctors use in HIV therapy, are an example of this.
- Cholesterol-lowering agents such as simvastatin or atorvastatin
- Oestrogen-containing preparations such as the contraceptive pill
- Painkillers such as ibuprofen, paracetamol or buprenorphine
Those affected should therefore always discuss the use of medication with their doctor.
Examinations and diagnosis
The doctor often diagnoses Meulengracht’s disease during a routine blood test if the level of bilirubin in the blood is elevated. Sometimes those affected also notice the yellowing of the sclera beforehand. In this case, it is advisable to consult a doctor. The doctor will first inquire about the exact course of the yellowing and other symptoms. This is followed by a physical examination.
The total bilirubin level in the blood should be less than 1.1 milligrams per deciliter. People with Meulengracht’s disease often have values between two and five milligrams per deciliter. Higher values indicate a different disease. Crigler-Najjar syndrome, for example, is often associated with bilirubin levels above 20 milligrams per milliliter. Different values apply for newborns.
Course of the disease and prognosis
In most cases, Meulengracht’s disease is completely harmless and only very rarely do the symptoms affect those affected. The older those affected get, the less frequent the attacks and symptoms occur. They often disappear completely in old age.
It is assumed that the mortality rate of people with mild hyperbilirubinemia is not increased. Some studies even suggest that elevated bilirubin levels protect against certain lung diseases and reduce mortality. The cosmetic problem caused by the yellowing of the eyes is sometimes a burden for people with Meulengracht’s disease.
Prevention
The metabolic disorder itself cannot be prevented, but it is possible to keep the bilirubin level in the blood low with simple measures, such as abstaining from alcohol and nicotine.
