ACHOLIA: CAUSES, PATHOPHYSIOLOGY AND TREATMENT - MEDICINE - 2024

The acolia is the lack of coloration of the feces due to lack of bile pigments in its structure. The English equivalent, acholia, refers more to the absence of bile discharge than to fecal discoloration, but they do claim that one of the consequences of acholia is the expulsion of pale or white stools.

Its etymology is very simple: the prefix «a-» means «without» or «lacking», and the rest of the word, colia, refers to bile and not to color, as can be believed due to its similarity in what is written and what is spoken. It would be literally translated as "no bile" or "devoid of bile."

There are several causes of acholia, all of which are related to a lack or decrease in the production and release of bile into the duodenum. The main cause is the obstruction of the bile ducts, basically the common bile duct. Treatment will depend on the cause, and may be surgical or medical.

Causes

Cholestasis

It is the blockage or cessation of bile flow, which prevents the bile from reaching the small intestine, specifically the duodenum.

In addition to acholia, cholestasis presents with coluria, jaundice, and severe itching. This condition is divided into two large groups, depending on the level of the obstruction or the origin of the problem:

Intrahepatic cholestasis

In this type of cholestasis, the damage that causes it occurs directly in the liver or the obstructed bile ducts are still within the liver parenchyma. There are pathologies that cause acute or chronic intrahepatic cholestasis, among which are:

Sharp

- Viral hepatitis.

- Toxic hepatitis.

- Postoperative benign cholestasis.

- Hepatic abscesses.

Chronicle in pediatrics

- Biliary atresia.

- Caroli disease.

- Byler's disease.

- Arteriohepatic dysplasia.

- Alpha-1-antitrypsin deficiency.

Chronic in adults

- Sclerosing cholangitis.

- Biliary cirrhosis.

- Cholangiocarcinoma.

- Autoimmune hepatitis.

- Sarcoidosis.

- Amyloidosis.

Other

- Heart failure.

- Cholestasis of pregnancy.

- Hodgkin's disease.

- Recurrent benign cholestasis.

Extrahepatic cholestasis

In this case there is no direct damage to the liver, but rather an exogenous obstruction of the bile ducts due to different causes, including the following:

- Gallstones (choledocholithiasis).

- Tumors in the head of the pancreas.

- Cancer of the bile ducts.

- Cholangitis.

- Pancreatitis.

- Common bile duct cysts.

- Biliary ascariasis.

Drugs

Drug-induced hepatotoxicity accounts for up to 40% of cases of drug-caused liver failure, and its consequences include compromised bile flow and acholia.

There are many drugs capable of inducing liver damage, which is why only the most important are mentioned by group:

Antibiotics

- Cephalosporins.

- Macrolides.

- Quinolones.

- Penicillins.

Psychotropic

- Chlorpromazine.

- Haloperidol.

- Barbiturates.

- Sertraline.

Anti-inflammatories

- Diclofenac.

- Ibuprofen.

- Meloxicam.

- Celecoxib.

Antihypertensive

- Captopril.

- Irbesartan.

- Methyldopa.

Cardiovascular agents

- Diuretics.

- Clopidrogrel.

- Warfarin.

Hypoglycemic agents

- Glimepiride.

- Metformin.

Others

- Steroids.

- Statins.

- Ranitidine.

- Cyclophosphamide.

- Parenteral nutrition.

Pathophysiology

Bile, commonly known as gall, is produced by the liver and stored in the gallbladder. This substance not only fulfills digestive tasks, helping with the emulsion of fatty acids, but also helps with the transport and elimination of certain waste products.

This last task is important when it comes to the degradation of hemoglobin. The final elements when hemoglobin is separated are globin and the "heme" group, which is finally transformed into bilirubin and iron after being subjected to a series of biochemical processes in the liver.

Bilirubin

Bilirubin is initially found outside the liver in its unconjugated or indirect form. Transported by albumin, it reaches the liver where it binds to glucuronic acid, conjugates and then accumulates in the gallbladder. There it joins with other elements such as cholesterol, lecithin, bile salts and water, to form bile.

Bile

Once bile is formed and stored, certain specific stimuli are expected for its release. These stimuli are usually the intake of food and the passage of the same through the digestive tract. At that time, the bile leaves the gallbladder and travels to the duodenum, through the bile ducts and the common bile duct.

Once in the intestine, a certain percentage of the bilirubin that makes up the bile is transformed by the intestinal flora into urobilinogen and stercobilinogen, colorless and water-soluble compounds that follow different pathways. Stercobilinogen is oxidized and becomes stercobilin, which gives the stool a brown or orange hue.

This whole process can be altered when the production of bile is insufficient or when its release is partially or totally limited by an obstruction of the bile ducts.

Acholic stools

If the bile does not reach the duodenum, the bilirubin is not transported to the small intestine and the action of intestinal bacteria on it is not possible.

Due to this, there is no production of stercobilinogen and less of its oxidation product, stercobilin. As there is no element that stains the stool, they are expelled colorless or pale.

The authors give different shades to acholic stools. Some describe them as pale, clay-colored, putty, clear, chalk, or simply white.

What is significant about all this is that acholic stools will always be related to a disorder in the production or transport of bile, being a very guiding clinical sign for the doctor.

Treatment

To eliminate acholia, the cause of it must be treated. Among the therapeutic alternatives are medical and surgical.

Surgical treatment

Choledochal stones are often resolved through lower digestive endoscopies, but those that accumulate in the gallbladder require surgery.

The most common operation is cholecystectomy or removal of the gallbladder. Some tumors can be operated on to restore bile flow, as well as local strictures and cysts.

Medical treatment

Infectious causes of cholestasis, acute or chronic, should be treated with antimicrobials. Liver and bile abscesses are often caused by multiple germs, such as bacteria and parasites, so antibiotics and anthelmintics can be helpful. Penicillins, nitazoxanide, albendazole and metronidazole are of choice.

Autoimmune and depot pathologies are usually treated with steroids and immunomodulators. Many cancer diseases that cause cholestasis and acholia must be treated initially with chemotherapy, and then possible surgical alternatives are considered.

References

1. Rodés Teixidor, Joan (2007). Jaundice and cholestasis Common Gastrointestinal Symptoms, Chapter 10, 183-194.
2. Borges Pinto, Raquel; Reis Schneider, Ana Claudia and Reverbel da Silveira, Themis (2015). Cirrhosis in children and adolescents: An overview. Wolrd Journal of hepatology, 7 (3): 392-405.
3. Bellomo-Brandao MA et al. (2010). Differential diagnosis of neonatal cholestasis: clinical and laboratory parameters. Jornal de Pediatria, 86 (1): 40-44.
4. Morales, Laura; Velez, Natalia and Germán Muñoz, Octavio (2016). Hepatotoxicity: drug-induced cholestatic pattern. Colombian Journal of Gastroenterology, 31 (1): 36 - 47.
5. Wikipedia (2017). Acolia. Recovered from: es.wikipedia.org