Transient Bloating of the Abdomen
Abdominal bloating is one of the common symptoms that a person experiences, either with disease or even in the absence of disease, yet it is not always easily explained. In most instances it is fluctuating and therefore referred to as transient bloating. However, sometimes abdominal bloating is persistent, either staying constant, increasing or decreasing distension. The two most commonly thought of causes for transient bloating is gas or fluid accumulation. However, gas in the gut is rarely able to distend the abdomen to a degree that causes noticeable bloating without the gas first being evacuated through either end of the gut.
Fluid accumulation in the abdominal cavity, or more specifically the abdominal cavity, is unlikely to cause noticeable distention unless it is in excess of 1 liter of fluid. A mass is unlikely to be the cause of transient abdominal distention. Only very large masses can cause noticeable distention and it usually increases with size or may shrink over a long period of time. Therefore abdominal distention that fluctuates on a daily basis cannot be due to any solid or fluid-filled growth.
Functional bloating is a condition where abdominal distension occurs for no known reason. It arises in the absence of any disease. This is often the reason for transient abdominal distention in most people. Some of the more common lifestyle and physiological causes of persistent bloating includes :
- Air swallowing (aerophagia).
- Excessive intake of carbonated beverages.
Persistent Bloating Causes
Persistent bloating, particularly when the abdominal distension is worsening day by day, needs to be investigated. It may often be due to harmless causes similar to that of transient bloating. However, serious causes of bloating need to be excluded. In most cases persistent bloating is due to some underlying disease and other symptoms will inadvertently arise over time. Therefore the bloating along with the other symptoms need to be considered as a whole in order to reach a diagnosis.
The six F’s of abdominal distension should always be considered :
- Flatus – gas.
- Fetus – pregnancy.
- Fat – abdominal obesity.
- Feces – constipation.
- Fluid – ascites.
- Female – menstrual bloating.
More specific causes of persistent bloating includes :
Abdominal Wall or Peritoneal Cavity
- Trauma - injury to the abdominal wall
- Hematoma – collection of blood in the abdominal wall.
- Ascites – fluid accumulation in the peritoneal cavity.
- Peritonitis – inflammation of the peritoneum lining the cavity.
- Hemoperitoneum – collection of blood in the peritoneal cavity.
- Internal bleeding – usually after trauma or post-operatively.
- Peritoneal dialysis.
- Abscess – collection of pus in the peritoneal cavity (intraperitoneal), behind it (retroperitoneal) or below diaphgragm (subphrenic).
- Hernia – weakening and protrusion of portion of the abdominal wall.
- Abdominal migraine – particularly in children.
- Gastroenteritis – stomach flu.
- Perforation – tear in the stomach usually from a complication of stomach ulcers.
- Stomach cancer.
- Gastroenteritis – inflammation of the stomach and small intestine mainly viral in origin.
- Diverticulitis – inflammation of the abnormal pouches of the bowels.
- Celiac disease – immune reaction in the bowels to gluten-containing foods (gluten intolerance).
- Inflammatory bowel disease – chronic inflammation of the bowels (Crohn’s disease / ulcerative colitis) and sometimes the upper gut Crohn’s disease only).
- Irritable bowel syndrome – functional bowel disorder which is either constipation or diarrhea predominant.
- Intestinal obstruction – partial or complete in small or large intestine.
- Ischemic bowel disease – blood supply to the bowel wall is interrupted and it may progress to an infarct.
- Lactose intolerance – dairy.
- Fructose malabsorption – fruit sugar.
- Intestinal parasites – infestation with parasitic worms (helminths).
- Laceration (bowel) – usually due to trauma.
- Toxic megacolon – inflammation of the colon with abnormal widening.
- Colorectal cancer – malignancy of the colon and/or rectum.
- Small bowel cancer – small intestines.
- Perforation – from ulcers, with injury or surgery.
- Pancreatitis – inflammation of the pancreas.
- Pancreatic cyst – fluid filled pocket within pancreas.
- Pancreatic cancer
- Splenic rupture – blood leaks from spleen into abdominal cavity.
- Splenomegaly – enlargement of the spleen.
- Splenic cancer – usually metastatic (originated elsewhere and spread to spleen) and includes leukemia and lymphoma.
Liver and Gallbladder
- Hepatitis – inflammation of the liver but is usually not responsible for bloating except in babies.
- Liver rupture – bleeding from the liver into the abdominal cavity often due to trauma.
- Liver abscess – collection of pus within liver.
- Gallstones and bile duct stones.
- Gallbladder empyema – collection of pus within gallbladder.
- Liver cancer
- Gallbladder cancer
Kidneys and Urinary Tract
Disorders of the urinary tract does not often cause abdominal distension.
- Kidney stones
- Polycystic kidney disease
- Uterine cancer
- Ovarian cancer
- Chronic leukemias
- Carcinoid syndrome
- Kwashiorkor (severe protein deficiency)
- Foreign body in the gut