Hospital Medicine

Right-upper quadrant abdominal pain

I. Problem/Condition.

Abdominal pain in general is perhaps one of the most difficult symptoms to evaluate. As a diagnostician, making an effort to specify location of the pain during history taking is very helpful in establishing a provisional diagnosis at the bedside and will aid in guiding further evaluation. It is also useful to understand a few basics about the pathophysiology of abdominal pain. In that respect abdominal pain can be classified into 3 varieties (visceral pain, parietal pain and referred pain):

Visceral pain

  • Caused by inflammation or ischemia of a visceral organ, obstruction and distension of a hollow viscus or stretching of a capsule.

  • Pain is carried along slow conducting C fibers hence it is dull in nature.

  • Often located at the midline because visceral innervation of abdominal organs is typically bilateral.

  • Pain is perceived in the abdominal region which corresponds to the diseased organ's embryonic origin, and hence:

    • Pain from organs proximal to the ligament of Treitz (embryonic foregut), including the hepatobiliary organs and spleen is felt in the epigastrium.

    • Pain from organs between the ligament of Treitz and the hepatic flexure of the colon (embryonic midgut) is felt in the periumbilical region.

    • Pain from organs distal to the hepatic flexure (embryonic hindgut) is perceived in the midline lower abdomen.

Parietal pain

  • Caused by direct irritation of the parietal peritoneal lining.

  • Parietal peritoneal afferents are A delta fibers with a rapid conduction velocity and hence parietal pain is sharp in nature.

  • Because parietal innervation is unilateral, lateralization of pain occurs.

Referred Pain

  • Occurs when visceral afferents carrying stimuli from a diseased organ enter the spinal cord at the same level as somatic afferents from a remote anatomic location e.g. pain of a sub-diaphragmatic process such as perforated duodenal ulcer or intraperitoneal hemorrhage may cause right shoulder pain due diaphragmatic irritation (C3, C4 and C5 dermatomes).

  • Typically well localized.

Right upper quadrant (RUQ) pain is pain that is localized in the right subcostal region of the abdomen. It may radiate superiorly over the lower anterior right hemithorax, medially as far as the epigastrium, posterolaterally towards the posterior right hemithorax or inferolaterally towards the right flank or right lower quadrant.

The pain can be of acute onset developing over a few hours or a few days or subacute to chronic being present over a few weeks to a few months. The quality of pain may vary from being described as a constant dull ache to a sharp pain which may be continuous or colicky and intermittent in nature. At times it may begin as colicky and then become continuous and persistent in nature.

II. Diagnostic Approach

A. What is the differential diagnosis for this problem?

In creating a differential diagnosis for Right-upper quadrant pain the very first step would be to divide the causes into:

  1. ABDOMINAL i.e. pain arising from a structure or organ in the region of the abdomen and

  2. EXTRA-ABDOMINAL i.e. "Referred Pain" arising from a structure or organ outside the abdominal region and being felt in the RUQ.

Abdominal causes

In general, a methodical way to think of abdominal pain is to subclassify it as arising from either one or a combination of the following layers from exterior towards the interior:

  • Abdominal wall

  • Peritoneum and peritoneal cavity

  • Viscera - intraperitoneal and retroperitoneal

  • Vasculature/lymphatics

Abdominal wall:

(i) Skin and subcutaneous tissues - cellulitis, herpes zoster (shingles).

(ii) Muscle - hematoma, rupture, strain.

Peritoneum and peritoneal cavity

(i) Peritonitis - localized to the RUQ e.g. after a perforated duodenal ulcer or ruptured gallbladder.

(ii) Intraperitoneal abscess/hemorrhage i.e. subdiaphragmatic abscess or ruptured abdominal aortic aneurysm

(AAA).

Viscera

In considering the etiologies under this heading the key concept would be to think of the RUQ in anatomic terms. This area primarily overlies the hepato-biliary system and disease states affecting this system are a very common cause of RUQ pain. Other relevant intra-abdominal viscera in this location include the duodenum, head of the pancreas, hepatic flexure of the colon, and the upper pole of the right kidney, and should be considered in the differential.

Most common etiologies include:

  • Liver - acute hepatitis (viral, alcoholic), hepatomegaly, Budd-Chiari syndrome, Fitz-Hugh-Curtis syndrome (perihepatitis), hepatic mass.

  • Gall bladder - acute cholecystitis, cholelithiasis.

  • Biliary tree - acute bacterial cholangitis (also known as ascending cholangitis), choledocholithiasis.

Less common etiologies:

  • Duodenum - duodenal ulcer (with or without perforation)

  • Pancreas - acute or chronic pancreatitis

  • Colon - colitis, diverticulitis, colonic mass, obstruction

  • Kidney - pyelonephritis, perinephric abscess, nephrolithiasis.

  • Diaphragm - sub-diaphragmatic abscess

Vasculature/lymphatics

(i) Mesenteric ischemia

(ii) Mesenteric adenitis

Extra-abdominal causes

"Referred pain" arising from structures or organs outside the abdominal region and being felt in the RUQ.

(i) From right lung

  • Lower lobe pneumonia

  • Pulmonary embolism

  • Pneumothorax

  • Pleurisy

(ii) From rib cage - right lower rib fracture (post-traumatic or pathologic from bone metastases).

(iii) From thoracic spine - radicular pain from mid to lower thoracic compression fracture.

(iv) From heart - inferior wall myocardial infarction.

B. Describe a diagnostic approach/method to the patient with this problem

History taking

  • Differentiate acute versus subacute or chronic pain.

  • Make sure pain is non-traumatic i.e. there is no recent history of blunt abdominal trauma or recent abdominal surgery.

  • Explore abdominal causes first unless other non-abdominal symptoms are more prominent and compelling e.g. dyspnea and cough in the setting of a right lower lobe pneumonia suggesting an extra-abdominal cause of RUQ pain.

  • Focus on hepato-biliary disease since it is a very common cause of RUQ pain.

Physical examination

  • Establish severity of the problem with particular focus on ruling out an acute surgical abdomen.

  • Establish patient stability - check vital signs, mental status and pulmonary condition.

  • Based on history and physical, establish a "working diagnosis" to guide further evaluation.

Diagnostics

  • Data - check relevant labs and order appropriate abdominal imaging (Kidney-ureter-bladder [KUB], RUQ ultrasound or computed tomography [CT] of abdomen and pelvis):

    • An upright KUB is particularly useful in the inpatient setting when abdominal pain has developed acutely in a hospitalized patient and the exam does not show any "peritoneal signs" (see physical exam below). It is a quick way of looking for evidence of "free air under the diaphragm" if duodenal or colonic perforation is suspected, or if looking for air-fluid levels and distended bowel loops if obstruction is suspected. A KUB may also pick up a radio-opaque kidney stone.

    • If there is any concern for acute mesenteric ischemia or evidence of an acute abdomen with peritoneal signs, a CT Abdomen would be more appropriate.

  • Consultation -initiate surgical consultation urgently if signs of "peritonitis" or suspicion for "an acute surgical abdomen", and also early in the work-up if examination is inconclusive but still concerning.

1. Historical information important in the diagnosis of this problem.

1. When did the pain start or how long have you been having RUQ pain?

Acuity, intensity and duration of pain maybe helpful in assessing severity of disease. A sudden onset of pain suggests a serious intra-abdominal event such as an organ perforation (duodenal ulcer perforation, colonic diverticular perforation) or ischemia (ischemic colitis) or obstruction of a small tubular structure (renal pevis or ureteric stone).

A more gradual onset of symptoms (a few days) suggests an infectious or inflammatory cause (acute cholecystitis or gastroenteritis) or obstruction of a large tubular structure (colonic obstruction).

2. Any recent trauma to this area? Any recent abdominal surgery?

Rule out trauma as the cause of the pain.

3. Have you ever had this problem before?

If present, it suggests a chronic intermittent problem e.g. cholelithiasis, diverticulitis, nephrolithiasis.

4. Any history of gall bladder or liver disease? Any history of pancreatitis, peptic ulcer disease, diverticulosis, Crohn's disease or ulcerative colitis? Any history of coronary artery disease? Any prior abdominal surgeries - specifically cholecystectomy, biliary surgery or biliary stents?

This line of questioning helps rule out certain possibilities and make some more likely.

Any intra-abdominal medical devices e.g. ventriculoperitoneal shunt presence raises index of suspicion for intra-abdominal infection (peritonitis, intra-abdominal abscess).

5. Is the pain dull and constant or is it colicky in nature?

May suggest biIiary colic, intestinal obstruction or nephrolithiasis.

6. Burning pain?

Seen in peptic ulcer disease.

7. Does it radiate to the back, to the shoulder or to the right flank?

Acute pancreatitis (pain radiates to the back), acute cholecystitis (pain may be referred to the right shoulder or right infrascapular region) and renal colic/ureteric colic pain may radiate to the right flank.

8. Any aggravating or relieving factors? Does it get worse after eating food?

Post-prandial pain of chronic mesenteric ischemia or duodenal ulcer.

9. Any relief from antacids?

If so, it suggests peptic ulcer disease.

10. Does sitting up make it worse or better?

Patients with acute pancreatitis may feel relief on sitting up and leaning forwards.

11. Does movement make it worse?

Indicates possibility of peritonitis.

12. Does deep inspiration or coughing aggravate the pain?

Suggests pulmonary causes of RUQ pain.

13. Any associated nausea or vomiting?

Though a non-specific complaint, in the presence of abdominal distension and constipation may indicate intestinal obstruction. Also a common symptom in peptic ulcer disease and cholelithiasis.

14. Any fever or chills?

Not specific but puts infectious and inflammatory conditions higher on the list (acute cholecystitis, acute cholangitis and diverticulitis).

15. Any diarrhea? If yes, then any recent antibiotic use within the past 6 - 8 weeks or recent consumption of restaurant or stale food?

ThinkC. difficile enterocolitis or other infectious colitis.

16. Any constipation? When was your last bowel movement? If no bowel movement, are you passing flatus? Any abdominal bloating or distension?

Think intestinal obstruction if constipation or obstipation present.

17. Have you noted yellow discoloration of your eyes or dark orange urine lately?

Jaundice with RUQ pain immediately suggests possibilities of hepatocellular disease (e.g. hepatitis), extrahepatic cholestatic disease (biliary obstruction as in choledocholithiasis or acute cholangitis) and gall bladder (GB) disease (acute cholecystitis).

18. Any black stools or bright red blood per rectum? If bright red blood, was it associated with straining on defecation or rectal pain during defecation?

In the acute setting this may suggest ischemic colitis; in the sub-acute or chronic setting it may suggest colon malignancy.

Bloody diarrhea may be suggestive of an infectious enterocolitis or inflammatory bowel disease.

19. Any hematuria, urinary frequency or dysuria?

Suggestive of pyelonephritis or nephrolithiasis.

20. Any vaginal discharge or history of sexually transmitted diseases?

In the setting of active pelvic inflammatory disease, RUQ pain may indicate perihepatitis (Fitz-Hugh-Curtis syndrome).

21. Any associated shortness of breath or cough?

Suggests pulmonary causes of RUQ pain.

22. Do you drink alcohol? Any cocaine use?

Heavy alcohol use raises the possibility of alcoholic hepatitis, hepatomegaly and acute pancreatitis as causes of RUQ pain. Cocaine use raises index of suspicion for mesenteric ischemia even in young patients.

2. Physical Examination maneuvers that are likely to be useful in diagnosing the cause of this problem.

Inspection

  • Examine the eyes for scleral icterus and pallor.

  • Expose the abdomen from the xiphisternum to the upper third of both thighs so that both inguinal areas are well in view.

  • Inspect the RUQ.

  • Does the abdominal wall move normally with respiration? Lack of movement whether localized or diffuse suggests peritonitis.

  • Look for any redness in the skin (cellulitis) or vesicular rash (shingles).

  • Make note of any old surgical scars - typical scars found in this location would be a subcostal incision from an open cholecystectomy or a small scar from a laparoscopic cholecystectomy.

  • Other less common scars - transverse scar extending into the epigastrium from prior pancreatic surgery (whipple procedure).

  • Look for any open wounds, bruises (signs of trauma).

  • Look for any obvious swelling or fullness in the RUQ (asymmetric abdominal enlargement) - suggests hepatomegaly or other Intra-abdominal mass.

Percussion and palpation

Palpate and percuss the RUQ for hepatomegaly. Measure the Liverspan by percussion.

Palpate the RUQ - assess firmness and tenderness. If abdomen is soft, peritonitis is less likely to be present.

If firm or rigid, attempt to differentiate between "true rigidity" (involuntary guarding) and "voluntary guarding" as follows: Have the patient lay supine with legs flexed at the hips and the knees to relax the abdominal musculature. Place your hand flat over the abdomen using the flexor surface of all the fingers during palpation. Be careful not to use the tip of the fingers during palpation i.e. do not poke the abdomen. Palpate gently and as you are palpating ask the patient to take deep breaths in and out. Unlike true rigidity (involuntary muscle guarding), voluntary muscle guarding will disappear during expiration.

Murphy's Sign: Positive in acute cholecystitis - with the patient laying supine place your right hand just below the right costal margin at the lateral border of the right rectus abdominis muscle. Apply moderate pressure with the flat of your fingers and ask patient to take a deep breath in. In case of an acutely inflamed gall bladder, the patient will wince with a "catch" in their breath as the inflamed organ hits the examining hand at the height of inspiration.

Costovertebral angle tenderness - present in most cases of pyelonephritis and perinephric abscess.

Absence of RUQ tenderness on palpation suggests pain is "referred" from extra-abdominal causes of RUQ pain.

Peritoneal signs and symptoms

  • Abdominal pain is the hallmark of peritonitis.

  • Nausea and vomiting may be present due to associated ileus.

  • Patient with peritionitis is usually immobile since any movement worsens the pain.

  • On examination:

    • "Board-like" rigidity (involuntary muscle guarding).

    • "Silent abdomen" - bowel sounds none to minimal due to ileus.

    • Exquisitely tender on palpation along with rebound tenderness.

3. Laboratory, radiographic and other tests that are likely to be useful in diagnosing the cause of this problem

  1. Complete blood count (CBC)

  2. Basic metabolic profile

  3. Liver function tests (LFTs) and hepatitis serologies (in hepatocellular jaundice)

  4. Amylase and lipase

  5. Urinalysis

  6. 12 lead ECG

  7. Kidney-ureter-bladder (KUB)

  8. Right upper quadrant ultrasound

  9. CT scan of abdomen

  10. HIDA scan - for acute cholecystitis if RUQ ultrasound is inconclusive but index of suspicion is high and cholecystectomy is being considered.

C. Criteria for Diagnosing Each Diagnosis in the Method Above.

Hepatobiliary

Acute hepatitis

  • Acute to subacute onset of RUQ pain associated with jaundice.

  • Nausea, vomiting and anorexia.

  • May have history of alcohol abuse or a viral prodrome 4-6 weeks prior.

  • Exam: tender hepatomegaly, scleral icterus.

  • Labs: leukocytosis; markedly elevated AST, ALT (in thousands) and bilirubin (can be significantly high in alcoholic hepatitis, up to 30-35) ; elevated γ-GT (gamma glutamyl transpeptidase); acute hepatitis viral serologies may be positive in hepatitis A and B.

  • RUQ ultrasound - shows hepatomegaly.

Acute cholecystitis

  • Acute onset RUQ and/or epigastric pain with radiation to the right subscapular region or tip of shoulder.

  • May start off as "biliary colic" which usually last 4-6 hours but in this case becomes persistent.

  • Fever, chills

  • Nausea, vomiting

  • Leukocytosis

  • Normal or mildly elevated transaminases and bilrubin

  • RUQ tender on exam with localized guarding - positive Murphy's sign

  • Ultrasound - may show gallstones or sludge: a distended GB with thickened GB wall , pericholecystic fluid and Sonographic Murphy's sign is highly suggestive of acute cholecystitis

  • Positive HIDA scan

Cholelithiasis

  • Acute to subacute onset of colicky pain (biliary colic) - sometimes patient may have a chronic history of intermittent biliary colic.

  • Attacks may be brought on by ingestion of fatty foods

  • Typical attacks subside within 4-6 hours

  • May have associated nausea and vomiting

  • Negative Murphy's sign

  • Normal CBC and LFTs

  • Ultrasound - shows gallstones without pericholecystic fluid

Acute bacterial cholangitis

  • Charcot's triad - acute onset sharp RUQ pain, fever and jaundice

  • Reynold's pentad - Charcot's triad, mental status changes and septic shock

  • May have a history of choledochlithiasis, cholelithiasis or recent biliary stenting or instrumentation

  • Ill-appearing, febrile and anorexic

  • Exam: moderate to severe RUQ tenderness, scleral icterus

  • Labs: leukocytosis; mild to moderate elevation of transaminases (typically in hundreds) and predominantly direct hyperbilirubinemia suggestive of cholestasis. Blood cultures positive in 50% cases.

  • RUQ ultrasound - may show biliary dilatation (CBD > 1cm); may show gallstones or common bile duct (CBD) stones.

Choledocholithiasis

  • RUQ colicky pain - acute to subacute onset

  • No fever

  • Jaundice may or may not be present

  • Exam: mild RUQ tenderness

  • Labs: Leukocytosis; mild to moderate elevation of transaminases (typically in low one hundreds) and predominantly direct hyperbilirubinemia suggestive of cholestasis.

  • RUQ ultrasound - shows CBD stones and may show biliary dilatation (CBD > 1cm).

Other viscera

Peptic ulcer disease (duodenal ulcer [DU])

  • Usually present with epigastric pain but occasionally may radiate to the RUQ.

  • Pain from DU typically is post-prandial occurring 2 to 5 hours after food ingestion.

  • Burning, gnawing and hunger like quality.

  • Relieved by antacids, anti-secretory agents and food.

  • DU with perforation - acute worsening of pain associated with peritoneal signs on exam (tender and rigid RUQ and epigastrium).

  • If suspected perforation, urgently obtain upright and decubitus KUB to look for "free air" (about 60% sensitive). CT abdomen much more sensitive for perforation.

Acute pancreatitis

  • Typically acute onset of epigastric and RUQ sharp "bandlike" pain radiating to the back.

  • Pain may be relieved by siting up and leaning forwards.

  • May begin as biliary colic (gallstone pancreatitis) or within 1-3 days of an alcoholic binge (alcoholic pancreatitis).

  • Associated with nausea & vomiting.

  • Exam: based upon severity and can range from mild epigatric tenderness to severe tenderness with guarding. Typically, exam less impressive than the severity of symptoms.

  • In some cases, flank ecchymoses (Grey-Turner's sign) or periumbilical ecchymoses (Cullen's sign) develop when there is pancreatic necrosis with hemorrhage.

  • Labs: elevated amylase and lipase; leukocytosis; may have elevated transaminases in gallstone pancreatitis.

  • No further imaging necessary if clinical and biochemical picture consistent with acute pancreatitis.

  • CT abdomen with IV and oral contrast is the imaging of choice if patient does not improve with conservative treatment or who are suspected of having developed complications (pancreatic pseudocyst, pancreatic necrosis).

Kidney

Nephrolithiasis

  • Acute to subacute onset - may begin with a dull ache in the RUQ and right flank progressing to intense pain which begins to wax and wane and occurs in paroxysms (renal colic). Patient may have passed a stone or gravel in urine.

  • As the stone migrates down the renal pelvis and ureter, the pain may show a "loin to groin" pattern of distribution.

  • Hematuria - gross or microscopic seen in 70-90% patients.

  • Nausea and vomiting; urgency and dysuria particularly with distal ureteric stones.

  • Exam: patient uncomfortable due to pain, tender right flank but typically soft unless there is voluntary guarding.

  • Labs: Urinalysis (UA) may show evidence of hematuria or pyuria; CBC - may have a leukocytosis; basic metabolic panel (BMP) may show an elevated blood urea nitrogen (BUN) and creatinine if patient deydrated or there is significant ureteral obstruction.

  • Imaging of choice - non-contrast CT abdomen and pelvis.

Pyelonephritis

  • Acute onset of RUQ or right flank pain.

  • Fever (>100°C), malaise, nausea.

  • Costovertebral angle tenderness.

  • UA - pyuria and/or white blood cell (WBC) casts.

  • No imaging necessary unless suspicion for perinephric abscess.

Mesenteric ischemia

  • Acute onset severe periumbilical pain out of proportion to findings on clinical exam.

  • Typical patients - elderly with known risk factors such as atrial fibrillation, heart failure, peripheral vascular disease and history of hypercoagulability or young patient with an inherited hypercoagulable state (e.g. factor V Leiden mutation).

  • Exam: may be benign initially but may quickly progress as bowel infarction sets in and the abdomen may be distended and firm with peritoneal signs.

  • Useful labs: BMP may show a low bicarbonate suggestive of a metabolic acidosis; LACTATE may be elevated

  • Imaging of choice - CT abdomen and pelvis with IV contrast.

III. Management while the Diagnostic Process is Proceeding

A. Management of right-upper quadrant abdominal pain.

  • Check patient's vital signs to ensure hemodynamic stability and then closely monitor.

  • Assess patient's level of alertness, orientation and pulmonary status.

  • Quick focused history to rule out trauma (blunt or otherwise) as a cause of RUQ pain. If any history of such obtain CT abdomen to rule out intra-abdominal traumatic liver injury and hemorrhage.

  • During physical examination look for evidence of an overt or occult GI bleed and focus on need to rule out an "acute abdomen" i.e. look for any peritoneal signs.

  • If evidence of a gastro intestinal (GI) bleed (melena or occult blood positive) consider possibility of mesenteric ischemia.

  • If evidence or suspicion of peritonitis suspect a perforated viscus (duodenal ulcer or colonic perforation).

  • If patient with high fever, chills, jaundice and is toxic appearing, suspect ascending cholangitis.

  • If any of the above:

    • Establish IV access - initiate generous IV fluid hydration or if patient hypotensive, aggressive hydration.

    • For suspected perforation initiate broad spectrum IV antibiotics - piperacillin/tazobactam, metronidazole, diflucan and consult surgery urgently.

    • For suspected cholangitis - draw 2 sets of blood cultures and then start IV antibiotics - ampicillin/sulbactam or piperacillin/tazobactam OR a carbapenem, fluoroquinolone or cephalosporin. Add metronidazole for the non β-Lactam/β-Lactamase inhibitor regimens. Obtain urgent GI consultation for endoscopic biliary tree decompression and drainage.

  • Order appropriate abdominal imaging after the above is initiated.

  • If pulmonary symptoms/signs prominent - dyspnea, hypoxia and tachypnea consider work-up for pulmonary embolism and pneumonia.

  • In cases where the initial exam was unrevealing and symptoms persist, conduct serial abdominal exams to assess for development of any peritoneal signs.

B. Common Pitfalls and Side-Effects of Management of this Clinical Problem

Two special circumstances to be aware of when evaluating abdominal pain:

The elderly

This population does not always present with the classic signs and symptoms associated with different acute abdominal syndromes. In addition, historical information may be difficult to obtain and typical physical exam findings may be absent or hard to elicit. For example, fever and leucocytosis may not be a prominent finding in the presence of intra-abdominal infection in these patients. Thus, when evaluating this group, a carefully obtained history, a thorough physical exam and a high index of suspicion are very helpful in making the right diagnosis and correct management decisions.

The immunocompromised

In general, immunocompromised patients may lack the definitive signs of acute abdominal syndromes usually seen in immunocompetent patients. As in the elderly, they also may not mount a robust sytstemic response to acute illness and may lack a fever, leucocytosis or even peritoneal signs in acute abdominal crises. A high index of suspicion is required in evaluating this subset of patients. Certain acute abdominal syndromes are unique to immunocompromised hosts such as neutropenic colitis, graft-versus-host disease, drug-induced pancreatitis, pneumatosis ntestinalis, cytomegalovirus (CMV) and Fungal Infections.

What's the evidence?

Bengiamin, RN, Budhram, GR, King, KE, Wightman, JM. "Abdominal Pain". Rosen's Emergency Medicine,. Molsby Melsevier. 2009.

Millham, FH. "Acute Abdominal Pain". Sleisenger and Fordtran's Gastrointestinal and Liver Disease,. Saunders. 2010.

Das, S. A Manual on Clinical Surgery,. Oxford Handbook. 2001.

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