Viscera

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Viscera

The abdominal viscera are all the organs located in the abdominal cavity. All of these organs play a role in three vital functions: digestion, purification and reproduction. They can be affected by certain common pathologies (inflammation, tumors, malformations) or abnormalities which are specific to each organ. 

Anatomy of the abdominal viscera

The abdominal viscera are all the organs located in the abdominal cavity.

The viscera of the digestive tract

  • The stomach: a hollow muscular organ in the shape of a bean, it is located between the esophagus and the small intestine;
  • The small intestine: it includes a relatively fixed part, the duodenum, which is wrapped around the pancreas, and a mobile part, the jejuno-ileum composed of 15 or 16 U-shaped intestinal loops contiguous one after the other ;
  • The colon, or large intestine, is located between the small intestine and the rectum;
  • The rectum is the terminal segment of the digestive tract.

The viscera attached to the digestive tract 

  • The liver: located under the diaphragm, it is the largest organ in the human body. Triangular in shape, it has a reddish-brown appearance, crumbly and brittle, and its surface is smooth. It is made up of four lobes;
  • The gall bladder: a small bladder located under the liver, it is connected to the main bile duct (one of the ducts that drain the bile secreted by the liver) by the cystic duct;
  • The pancreas: located behind the stomach, this gland has two organs with internal and external secretion;
  • The spleen: a spongy, soft organ about the size of the fist, it is located just below the rib cage;
  • Kidneys: dark red bean-shaped organs, located on either side of the spine. The basic functional unit of the kidney, called the nephron, is made up of a filtering organ (the glomerulus) and an organ for diluting and concentrating urine (the tubule).

The vagina, uterus and ancillary organs (bladder, prostate, urethra) are urogenital viscera.

Physiology of the abdominal viscera

The abdominal viscera are involved in three major vital functions:

The digestion

In the digestive tract, ingested food is transformed into simple chemicals that can pass into the bloodstream.

  • The stomach performs a dual function: a mechanical function (stirring food) and a chemical function (the stomach contains hydrochloric acid which sterilizes food, and it secretes pepsin, an enzyme that breaks down proteins. );
  • In the intestine, the intestinal enzymes (those produced by the pancreas) and the bile excreted by the liver transform proteins, lipids and carbohydrates into elements that can be assimilated by the body;
  • The colon is the place where digestion ends thanks to the action of the microbial flora there. It is also a reservoir organ where food residues to be eliminated accumulate;
  • The rectum fills with the stools contained in the colon, resulting in the need to evacuate.

The liver is also involved in digestion:

  • It regulates blood sugar by converting excess glucose into glycogen;
  • It breaks down dietary fatty acids into products of high energy value;
  • It captures the amino acids that make up proteins and then stores them or lets them pass into the bloodstream according to the body’s needs.

Purification

Waste or toxic substances contained in the body are eliminated by:

  • The liver, which concentrates in the bile the substances to be excreted from which it has purified the blood which has passed through it;
  • The kidneys, which eliminate nitrogenous wastes and water-soluble toxins by making urine;
  • The bladder, which accumulates urine to be eliminated.

The reproduction

The vagina and uterus are viscera involved in reproduction.

Abdominal viscera abnormalities and pathologies

The stomach can be affected by the following abnormalities and pathologies:

  • Any wound in the abdomen can lead to damage to the stomach, which is manifested by contractures and the presence of air in the abdominal cavity.
  • Gastritis: chronic or isolated inflammation of the stomach lining
  • Stomach ulcer: loss of substance from the stomach lining
  • Tumors: they can be benign or cancerous
  • Stomach bleeding: this can be caused by ulcers, cancer, or hemorrhagic gastritis

The intestine can be affected by a number of conditions that can lead to obstruction, diarrhea, or a defect in the process that moves food through the intestinal barrier (malabsorption):

  • Congenital anatomical abnormalities such as the narrowing or absence of a portion of the intestine (congenital atresia)
  • Tumors
  • Twisting of the intestine around its point of attachment (volvulus)
  • Inflammation of the bowel (enteritis)
  • Intestinal tuberculosis
  • Intestinal or mesenteric infarction (retreat of the peritoneum that contains vessels that feed the intestine)

The colon can be affected by the following pathologies:

  • Inflammation of the colon of bacterial, toxic, parasitic, viral or autoimmune origin. It can result in diarrhea, and sometimes fever
  • Tumors manifested by hemorrhages, attacks of constipation or even intestinal obstruction
  • A functional colopathy, without functional damage, which manifests as spasms or diarrhea.

The pathologies that affect the rectum are as follows:

  • Traumatic injuries caused by foreign bodies, projectiles or impalement
  • Inflammation of the rectum (proctitis): frequent during hemorrhoid outbreaks, they can also be secondary to therapeutic irradiation of the pelvis
  • Benign (polyps) or cancerous tumors

The liver can be affected by a multitude of pathologies:

  • Hepatitis is inflammation of the liver of toxic, viral, bacterial or parasitic origin
  • Cirrhosis is degenerative disease of the liver tissue due to alcoholism (80% of cases) or other conditions (hepatitis, Wilson’s disease, obstruction of the bile ducts, etc.)
  • Parasitic disorders, including liver fluke disease often contracted from eating wild watercress
  • Liver abscesses of parasitic or bacterial origin
  • Benign tumors (cholangiomas, fibroids, hemangiomas)
  • Primary liver cancer that develops from liver cells

The liver can also be affected during cardiovascular diseases (heart failure, pericarditis, arterial embolism, thrombosis, etc.) and various general diseases, such as granulomatosis, thesaurismosis, glycogenosis or cancer of other organs, can localize in the liver. Finally, hepatic accidents can be observed during pregnancy.

The kidneys can be affected by different conditions classified according to the damaged tissue and the type of lesion:

  • Primary glomerulopathies, involving the glomerulus, can be benign and transient while others can progress to chronic renal failure. They result in a more or less important elimination in the urine of the proteins normally retained by the glomerulus. They are often associated with the emission of urine containing blood (hematuria) and sometimes with high blood pressure;
  • Secondary glomerulopathies appear during general diseases such as renal amyloidosis or diabetes;
  • Tubulopathies are damage to the tubule that can be acute when caused by ingestion of a toxic substance, or chronic. In the second case, they result in a defect of one or more tubular functions 
  • Kidney conditions that affect the supporting tissues between the two kidneys, called interstitial nephropathies, often result from urinary tract disease;
  • Conditions that affect the vessels in the kidneys, called vascular nephropathies, can lead to nephrotic syndrome or high blood pressure 
  • Kidney malformations such as hypoplasia (failure in the development of a tissue or organ) or polycystosis (progressive appearance of cysts along the tubule) are common 
  • Kidney failure is a decrease or suppression of the purifying function of the kidney. It results in an increase in urea and creatinine (a waste of metabolism) in the blood, often with edema and high blood pressure 
  • The kidneys can also be affected by surgical conditions such as trauma due to shock in the lumbar region, infections or tumor lesions. 
  • Nephroptosis (or a descended kidney) is a disease characterized by abnormal mobility and a low position of the kidney.

The vagina may be affected by congenital malformations (complete or partial absence of the vagina, partitions), vaginal tumors or fistulas which cause the vagina to communicate with the digestive tract or the urinary tract. An inflammatory condition in the lining of the vagina, called vaginitis, results in white discharge, burning, itching, and discomfort with intercourse.

The uterus may have birth defects (double, septate, or unicornuate uterus) which may cause infertility, abortions, or abnormal fetal presentations. It can present abnormalities of position, or be the seat of infections or benign or malignant tumors.

The bladder can be traumatic. A decrease in the rate of urine flow can lead to the development of stones in the bladder. Bladder tumors most often show up as bloody urine.

The urethra can be the site of a stricture, a stone or a tumor.

The most common condition of the prostate is prostatic adenoma, a benign tumor that manifests as an increased frequency of urination, changes in the pattern, and sometimes acute retention of urine. The prostate can also be the site of cancer or inflammation.

Treatments

Disorders of the digestive system (stomach, intestine, colon, rectum, liver, pancreas, gall bladder, spleen) are all managed by a gastroenterologist. In the event of specific rectal disorders, it is possible to consult a proctologist (specialist in the rectum and anus). Pathologies of the liver, spleen and bile ducts can be dealt with more specifically by a specialist in these organs, the hepatologist.

Medical management of kidney pathologies is provided by a nephrologist, and that of pathologies of the female genital system (vagina, uterus) by a gynecologist.

Diseases that relate to the urinary tract (bladder, urethra) and male genitalia (prostate) are managed by a urologist. The latter also provides surgical management of diseases of the kidney or the woman’s genital tract.

Diagnostic

The clinical examination

It involves palpation and percussion of the abdomen which can make it possible to detect significant changes in the volume and consistency of the liver, or to perceive a large kidney.

Functional exploration

There is a whole set of tests to explore how well the different abdominal viscera are functioning.

The secretory function of the pancreas can be explored by:

  • A test of an enzyme (amylase) in the blood and urine
  • Duodenal tubing: a probe is introduced into the duodenum to collect the pancreatic sugar obtained after stimulation of the excretion of the gland
  • A stool examination: pancreatic insufficiency causes poor digestion which results in abundant, pasty and fatty stools

Functional exploration of the kidney includes:

  • A chemical examination of the urine to detect elimination of proteins in the urine which indicates a dysfunction of the filter function of the glomerulus
  • Urea and creatinine blood tests to check the effectiveness of the kidney cleansing blood

X-ray of the abdomen

  • Spotting foreign bodies in the stomach
  • Stomach cancer
  • The radiological examination of the stomach makes it possible to highlight inflammations of the lining of the stomach

Digestive radiography

It consists of swallowing a product opaque to X-rays and studying the progression of this product through the esophagus, stomach, duodenum and bile ducts. It allows a morphological study of the internal walls of these different organs. Fasting is essential to allow the product to adhere to the digestive walls. It is used in the diagnosis of gastric bleeding.

Endoscopy

This examination consists in introducing an optical tube fitted with a lighting system into a cavity to examine it. When the endoscopy is to look at the stomach, duodenum, liver, or genitals, the test is called esogastroduodenal endoscopy or “esogastroduodenal endoscopy, and the tube is inserted through the mouth. When performed to observe the colon, liver, bladder, or rectum, the endoscope is introduced through the anus. Endoscopy is performed in particular for the diagnosis of gastric hemorrhage, stomach cancer, colon tumor, inflammatory colon disease, liver abnormalities, etc.

Scintigraphy

Also called gamma radiography, it consists of examining an organ thanks to the accumulation at its level of chemical elements that emit gamma rays. Thanks to a ray detector which moves while scanning the surface to be studied, an image of the organ is obtained where the radioactive density indicates the proportion of fixed substance. Scintigraphy is used to explore:

  • Liver. It makes it possible to highlight cysts, abscesses, tumors or metastases.
  • The kidney. It allows to compare the symmetry of the two kidneys.

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