THE ABDOMINAL MASS: SIGNS AND CAUSES

HepatomegalySigns of an enlarged liver area are:- it descends from below the right costal margin and costal angle- it moves with respiration- it is dull to percussion- its edges can be sharp or rounded and its surface smooth or irregular

The causes of enlargement of the liver are classified in 5 categories:1. Smooth generalized enlargement without jaundice

- congestive heart failure- cirrhosis- hepatic vein obstruction

2. Smooth generalized enlargement with jaundice- infective hepatitis- biliary tract obstruction (biliary stones, carcinoma of the head of the

pancreas).- angiocholitis (infection of the biliary tree)

3. Knobby generalized enlargement without jaundice- secondary carcinoma- macronodular cirrhosis- polycystic disease- primary liver carcinoma

4. Knobby generalized enlargement with jaundice- extensive secondary carcinoma- cirrhosis with hepatic failure

5. Localized swellings- secondary carcinoma- hydatic cyst- liver abscess- primary liver carcinoma

SplenomegalyThe causes of splenomegaly are best classified according to the underlying disease.

1. Infection- typhoid- tuberculosis- septicemia- syphilis- leptospirosis- malaria

2. Cellular proliferation- lymphatic leukaemia- pernicious anemia- spherocytosis

3. Congestion- portal hypertension - cirrhosis

- portal vein obstruction- congestive heart failure

4. Infarction- emboli from bacterial endocarditis, emboli from the left atrium during atrial fibrillation associated with mitral stenosis, emboli from the left ventricle after myocardial infarction.- splenic artery or vein thrombosis in polycytemia and retroperitoneal malignancy.5. Cellular infiltration

- amyloidosis- Gaucher’s disease

6. Space occupying lesions- true solitary cysts- polycystic disease- hydatic cyst- angioma- lymphoma

The physical signs of an enlarged spleen are:- it appears from below the tip of the left 10th rib and enlarges along the line of the rib towards the umbilicus.- it is firm, smooth with a definite notch on its upper edge- you cannot get above it- it moves with respiration, dull to percussion- it may be possible to bring it forwards

Enlargement of the kidneyThe common causes of enlargement of the kidney are:- hydronephrosis- pyonephrosis- perinephric abscess- carcinoma of the kidney- polycystic diseases

The physical signs of an enlarged kidney are:- it lies in the paracolic gutter or can be pushed back into this gutter; that is to say, it can be reduced into the loin.- it is usually only possible to feel the lower pole, which is smooth and hemi-ovoid.- it moves with respiration, slightly.- it is not dull to percussion because it is covered by the colon. Even when a large kidney reaches the anterior abdominal wall it has a band of resonance across it.- it can be felt bimanually.- it can be ballotted. This means that it can be bounced between the hands. This sign is diagnostic of a renal mass and depends upon the mass reducing into the loin.

Pancreatic pseudocystThis is a collection of pancreatic secretion caused by pancreatitis on the surface of the pancreas or in part of the whole of the lesser sac.If the cyst becomes infected the patient will develop severe pain, sweating and rigors, fever, tachycardia.The physical characteristics of a pancreatic pseudocyst are:- the epigastric region contains a firm, sometimes tender, mass with an indistinct lower edge. The upper limit is not palpable.- it is usually resonant to percussion because it is covered by the stomach.- it moves very slightly with respiration.- it is not possible to elicit fluctuation or a fluid thrill.

Carcinoma of the stomachAlthough stomach cancers are often large hard masses, they are difficult to feel because they are high in the abdomen, beneath the costal margin.If there is a palpable mass it will be hard and irregular, it will disappear beneath the costal margin so you cannot get above it and move with respiration.

The symptoms such as, abdominal pain or indigestion with loss of appetite and weight are far more significant than the physical signs.The common finding in a patient with carcinoma of the stomach is a normal or slightly tender epigastrium.Thus although carcinoma of the stomach can present with an abdominal mass the message is do not expect to feel a mass in a patient with carcinoma of the stomach.

The gall bladderThe causes of enlargement of the gall bladder are:1. Obstruction of the cystic duct, usually by a gallstone, rarely by an intrinsic or extrinsic carcinoma.The patient is not jaundiced and the gall bladder will contain bile, mucus or pus. The pain is severe.2. Obstruction of the common bile duct, usually by a stone or a carcinoma of the head of the pancreas. The patient will be jaundiced. Courvoisier’s law states: ”when the gall bladder is palpable and the patient is jaundiced the obstruction of the bile duct causing the jaundice is unlikely to be a stone because previous inflammation will have made the gall bladder thick and non-distensible”.The physical features of an enlarged gall bladder are:- it appears from beneath the tip of the right 9th rib.- it is smooth and hemi-ovoid.- it moves with respiration.- you cannot feel a space between the lump and the edge of the liver.- it is dull to percussion.If the gall bladder is acutely inflammed it becomes surrounded by adherent omentum and bowel and loses some of its characteristics.A gall bladder mass is diffuse and tender, lies in the right hypocondrium and does not move much with respiration. As the infection subsides it becomes more discrete and mobile and less tender.

The urinary bladderThe physical features of an enlarged bladder are:- it arises out of the pelvis and so it has no lower edge.- it is hemi-ovoid in shape, usually deviated a little to one side. - it may vary in size; a very large bladder can extend up above the umbilicus.- it is not mobile.- it is dull to percussion.

- if it is large enough to permit the necessary simultaneous percussion and palpation it will have a fluid thrill.- direct pressure on the swelling often produces a desire to micturate.- it does not bulge into the pelvis and can only be felt indistinctly on bimanual examination.

Ovarian cystSmall ovarian cysts are common and are not palpable. When they enlarge they rise up out of the pelvis into the lower abdomen and become palpable.The physical features of a large ovarian cyst are:- like all cysts, it is smooth and spherical with distinct edges.- it arises from the pelvis so its lower limit is not palpable you cannot get below it.- it may be mobile from side to side but cannot be moved up and down.- it is dull to percussion.- its lower extremity may be palpable in the pelvis during rectal or vaginal examination and movement of the cyst may produce some mavement of the uterus.

FibroidsFibroids can grow to an enourmous size and fill the whole abdomen.They cause irregular and heavy periods, disturbed micturition, lower abdominal pain and backache.The physical signs of a fibroid uterus:- it arises out of the pelvis and so the lower edge is not palpable.- it is firm or hard bosselated or distinctly knobby - each knob corresponding to a fibroid.- the mass moves slightly in a transverse direction and any movement of the abdominal mass moves the cervix (PV + abdominal palpation).- it is dull to percussion.

The causes of a mass in the right iliac fossaA mass in the RIF is a common physical finding and there are many possible causes to remember when you are considering the diagnosis.Apendix massThis is a tender indistinct mass, dull to percussion fixed to the iliac fossa posteriorly. The patient will have a persistent fever and tachycardia.

Appendix abscess

This is a tender mass which in its late stages may fluctuate and be associated with oedema and reddening of the overlying skin. The patient will have a swinging fever and an increasing tachycardia.

Ileocecal tuberculosisThis is an inflammatory mass in the RIF which consists of the inflammed ileocecal lymph nodes and parts of the cecum and terminal ileum that are also inflammed. The mass is firm, tender and indistinct. The surface and the edge are difficult to define. If there is a tuberculous peritonitis the abdomen will be swollen and less flexible.

Carcinoma of the cecumThe mass is firm and distinct. Sometimes is fixed to the posterior abdominal wall but sometimes it is mobile. It is not tender and does not resolve with observation.

Crohn’s diseaseThe swollen terminal ileum forms an elongated sausage-shaped mass which is rubbery and tender. It lies in a transverse position and slips up and down the abdomen during palpation.

The causes of a mass in the LIF are identical to those of a mass in the RIF, with the exception of appendicitis, carcinoma of the cecum and tuberculosis which are replaced by diverticulitis and carcinoma of the sigmoid colon.

DiverticulitisDiverticular disease appear in the colon especially the sigmoid colon, these acquired diverticula appear probably as a result of change in the bowel motility and the hard consistence of the feces.When the diverticula become acutely inflamed, the condition is called diverticulitis.Examination. The LIF contains a very tender indistinct mass whose long axis lies parallel to the inguinal ligament. There may be a general or a local peritonitis and intestinal obstruction.

Carcinoma of the sigmoid colonThe mass is hard, easily palpable and not tender. It may be mobile or fixed. The colon above the mass may be distended with indentable feces.

Abdominal distension

The causes of abdominal distension can be remebered by using the letter “f” six times: fetus, flatus, feces, fat, fluid, fibroids and other solid tumors.

FetusPregnancy is the most common cause of abdominal distension.The uterus enlarges to the xiphisternum by the 36th week of pregnancy.The diagnosis of pregnancy is more difficult in the first 20 weeks when the uterus is smaller and there are no fetal movements.A pregnant uterus is a smooth, firm, dull swelling arising out of the pelvis.The diagnosis is made with a bimanual examination which reveals that the mass cannot be moved independently of the cervix and the cervix is soft and patulous.

FlatusGas in the intestine can cause considerable abdominal distension.In the early stages the distension may be localized to the part of the abdomen containing the distended gut such as the epigastrium when the stomach is distended or the right iliac fossa when the cecum is distended but as the distension progresses through the gut the whole abdomen swells.The distension will remain localized if the bowel twists into a volvulus. This is a common complication of a long sigmoid colon combined with a narrow base of the mesocolon.The only diagnostic feature is hyperresonance and when there is obstruction, visible peristalsis. The bowel sounds may be hyperactive.Percussion causes a splashing sound as the fluid in the distended bowel splashes about.This is known as a succusion splash and is particularly common in gastric distension secondary to pyloric stenosis.The causes of flatus are acute dilatation of the stomach, mechanical intestinal obstruction and paralytic ileus.

FecesFecal impaction may present as abdominal distension or an abdominal mass.The physical characteristics of feces are:- the masses lye in that part of the abdomen occupied by the colon; the flanks and the lower part of the epigastrium.- feces feel firm but are indentable. This means that they can be dented by firm pressure with the fingers and this dent persists after releasing the pressure.

- there may be multiple separate masses in the line of the colon but in gross cases the feces coalesce to form one vast mass which is easy to mistake for a tumour.- when there is no mechanical obstruction, rectal examination will reveal a rectum full of rock-hard feces but if there is a blockage in the lower colon, the rectum will be empty.The diagnosis can usually be suspected from the history of the patients’s bowel habits.The common causes are Hirschsprung’s disease, acquired megacolon, chronic intestinal obstruction and chronic constipation.

FatFat rarely causes distension but frequently makes the patient pot-bellied. A large fat abdomen may be caused by a thick layer of subcutaneous fat or by excess fat in the omentum and mesentery.

FluidAscites - fluid that is free in the peritoneal cavity is called ascites.It is caused by a variety of conditions but they all fall into four groups: those which raise the portal venous pressure, those which lower the plasma proteins, those which cause a peritonitis and those which allow a direct leak of lymph into the peritoneal cavity.The causes of increased portal venous pressure1. Prehepatic- portal vein thrombosis

- compression of the portal vein by lymph nodes2. Hepatic- cirrhosis

- multiple hepatic metastases3. Posthepatic- obstruction of the hepatic veins4. Cardiac - constrictive pericarditis

- right heart failure5. Pulmonary - pulmonary hypertension

- right heart failure

The causes of hypoproteinemia1. kidney disease associated with albuminuria2. cirrhosis3. malignancies and starvation4. protein-loosing enteropathies

The causes of chronic peritonitis

1. Physical - post irradiation - talc granuloma

2. Infection - tuberculous peritonitis

3. Neoplasms - secondary peritoneal deposits of carcinoma - mucous-forming tumours (pseudomyxoma peritonei)

The causes of chylous ascitisChylous ascites is caused by leakage from the cisterna chyli or its branches as a result of congenital abnormalities, trauma and primary or secondary lymph gland disease.

The physical signs of ascites are:- a fluid thrill- shifting dullnessA fluid thrill is elicited by flicking one side of the abdomen with your fingers and feeling the vibrations when they reach the other side of the abdomen with your other hand.Before doing this you must place the edge of an assistant’s hand on the abdomen at the umbilicus to prevent the percussion wave being transmitted in the abdominal wall.Shifting dullness is a dull area which moves or changes shape when the patient changes position.The dullness of ascites is found in the flanks and across the lower abdomen.Percuss the medial limits of the flank dullness carefully. Then ask the patient to turn on his side to an angle of 45 degrees. Wait a few seconds and percuss again. If there is free fluid moving under the influence of gravity the medial limit of dullness will have extended towards the mid-line on the lower side of the abdomen and retracted on the upper side.

Fluid trapped in a cyst will have a fluid thrill, be dull to percussion but not shift.The following cysts or fluid-filled swellings may become large enough to present as abdominal distension: ovarian cysts, polycystic kidney, pancreatic cysts, hydatid cysts.

Solid tumours

The solid tumours which can become so large that they may cause abdominal distension are: fibroids, hepatomegaly, splenomegaly, large cancers of the colon, pancreas, kidney, liver.