Distention of abdomen can be due to an underlying disease or due to accumulation of fat. Normal abdomen distention needs to be differentiated from that due to disease.
Generalized distension occurs in ascites, obesity and patients with excessive flatus. Localized distension occurs with individual visceromegaly and with neoplasms.
Here are the differentiating points.
Fat
In this case abdomen is pendulous. The abdomen with symmetrical, globular, enlarged and accentuated cutaneous folds.
Flatus
This is characterized by generalized tympany which is more at the periphery. Tympany is a hollow drum-like sound produced when a gas-containing cavity is tapped.
Feces
It produces generalized distension occurs which is more in the flanks. Some focal masses may be palpable.
Fetus
Usually there would be history of amenorrhoeoa but it is important to differentiate as few patient may fail to reveal it. It produces central dullness, tympany in the flanks.
Full bladder
Tender, rounded, cystic mass may be palpable above symphysis pubis . In conscious and neurologically intact patient, there might be pain and tenderness or urge to micturate.
New growth: Usually it pertains to malignancy. Abdomen is dull overlying the growth. In ovarian growth, the distance between the umbilicus and the symphysis pubis is greater than that between the xiphisternum and the umbilicus
