Jaundice (jaundice): what is it exactly?
First thing to know: the bilirubin is a protein that results from the breakdown of red blood cells – this process is called hemolysis. Carried by albumin in the bloodstream, initially “unconjugated” bilirubin combines with a molecule (glucoronic acid) to form “conjugated” bilirubin. This is then filtered by the kidneys and then naturally eliminated in the urine.
What is jaundice? When the bilirubin elimination process is malfunctioning, this “waste” accumulates in the bloodstream: when the blood bilirubin level exceeds 40 μmol / L (micromole per liter of blood), a yellow coloration of the skin appears. – it is jaundice or “jaundice” in medical language.
Jaundice: what are the symptoms? ” The main symptom of excess plasma bilirubin is yellowing of the skin, as bilirubin is a yellow-ocher pigment. “explains Dr. Olivier-Jacques Bocrie-Jeantet, general practitioner. This yellow coloration (more or less marked: from straw yellow to egg yolk) is especially visible on the face, forehead, hands and mucous membranes.
” Added to this is a yellowish discoloration of the conjunctiva, i.e. the white of the eye, and possibly itching of the skin (pruritus) “specifies the general practitioner. It is possible to have a complete jaundice (the skin and the conjunctiva are yellowish) or simply a” conjunctival subicterus “(the coloring is visible only at the level of the eye).
Jaundice (jaundice): diagnosis and additional examinations
Diagnostic. “ An excess of conjugated bilirubin in the blood is clinically manifested by colored urine (brownish: we speak of choluria) and by acholic stools (that is to say: discolored), develops Dr. Olivier-Jacques Bocrie-Jeantet. Conversely, an excess of unconjugated bilirubin in the blood is manifested through clear urine. “
Additional tests. ” The main additional examination is a blood test for bilirubin (bilirubinemia), to find out if there is an excess of bilirubin in the blood and if the protein is conjugated or not. “explains the doctor. A complete blood count (CBC) can also make it possible to demonstrate too rapid destruction of red blood cells (hyper-hemolysis) and / or a defect in liver enzymes.
” If there is an excess of conjugated bilirubin in the blood, medical imaging tests may be prescribed: a ultrasound of the liver, an abdominal scan or an abdomino-pelvic scan “adds Dr. Olivier-Jacques Bocrie-Jeantet.
Jaundice (jaundice): what can be the causes?
An excess of unconjugated bilirubin in the blood may be related to:
- Gilbert’s disease: without seriousness, this syndrome corresponds to a partial deficit of the hepatic enzyme which makes it possible to conjugate bilirubin,
- Sickle cell disease: this genetic disease that affects the hemoglobin of red blood cells results in chronic anemia,
- Thalassemias: these blood diseases (which are genetic and hereditary) cause more or less severe anemia,
- Malaria: also called “malaria”, this disease is caused by a parasite transmitted to humans by the bite of a mosquito,
- Hyperhemolysis (accelerated destruction of red blood cells) and dyserythropoiesis (insufficient production of red blood cells),
- More rarely: poisoning from a poisonous snake bite.
” As a rule, an excess of unconjugated bilirubin in the blood corresponds to an accelerated destruction of red blood cells and is accompanied by pallor and splenomegaly – that is, an increase in volume of the spleen. It is often a question of hemopathy “analyzes Dr. Olivier-Jacques Bocrie-Jeantet.
An excess of conjugated bilirubin in the blood may result from:
- Hepatic cirrhosis: this liver disease can in particular be the consequence of excessive and prolonged alcohol consumption,
- Hepatitis: five types of virus can cause hepatitis A, B, C, D or E,
- A gallstones: that is to say the presence of stones in the bile ducts,
- A tumor of the gallbladder,
- More rarely: a parasitic infection of the bile or intestines.
“ In case of excess conjugated bilirubin in the blood, there may be a question of liver or extrahepatic damage, notes the general practitioner. Jaundice associated with pain that goes up to the right shoulder and a fever over 38.5 ° C should suggest a angiocholite, therefore to a bile infection of the main bile duct: it is a medical emergency! “
Thanks to Dr. Olivier-Jacques Bocrie-Jeantet, general practitioner for Medadom.
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