I. Problem/Condition.

Abdominal pain in general is perhaps one of the most difficult symptoms to evaluate. As a diagnostician, making an effort to ascertain location of the pain during history taking is helpful in establishing a provisional diagnosis at the bedside and will also aid in guiding further evaluation. 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 pain isDULL in nature.

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  • Oftenlocated 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 isSHARP in nature

  • Because parietal innervation is unilateral,lateralization of painoccurs.

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. diaphragmatic irritation caused by bowel contents from a doudenal perforation causing right shoulder pain through the C3, C4 and C5 dermatomes).

  • Typically well localized.

Right lower quadrant abdominal painis pain that develops in the area of the abdomen just superior to the right inguinal ligament.

It may be acute in onset of a few hours to a few days duration or subacute or chronic, having developed over weeks to months. The etiology of RLQ pain is most commonly related to disease processes such as infection, inflammation, perforation, obstruction, neoplasia, vascular events, etc. affecting the underlying intra-abdominal organs in this anatomic location. The quality, intensity and duration of pain also depends upon the pathophysiology of the process as discussed later in the chapter.

II. Diagnostic Approach

A. What is the differential diagnosis for this problem?

In creating a differential diagnosis for right lower quadrant (RLQ) pain, the very first step would be to divide the causes into the following categories:

1) ABDOMINAL i.e. pain arising from structures in the region of the abdomen, and

2) EXTRA-ABDOMINAL i.e. “referred pain” arising from structures outside the abdominal area but perceived in the RLQ.

Abdominal causes

A useful way to think of abdominal pain to establish its etiology 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

a)Abdominal wall

Skin & subcutaneous tissues – cellulitis, herpes zoster (shingles), tumor.

Muscle – hematoma, rupture, strain.

Inguinal canal – inguinal hernias (specific to the lower abdominal quadrants).

b)Peritoneum and peritoneal cavity

  • Peritonitis – localized to the RLQ e.g. as in acute appendicitis or cecal perforation.

  • Intraperitoneal abscess/hemorrhage e.g. diverticular abscess or ruptured abdominal aortic aneurysm (AAA).

c)Viscera: (Intraperitoneal and retroperitoneal)

In considering the etiologies under this heading, the key concept would be to think of the RLQ in anatomic terms. This area primarily overlies the Ileocecal junction and appendix and disease states affecting these organs are a common cause of RLQ pain.

Other relevant intra-abdominal viscera in this location include the proximal half of the ascending colon, lower pole of right kidney, right ureter and in females – the right ovary and fallopian tube and certain conditions affecting these organs should be considered in the differential.

Most common etiologies include:

  • Appendix – acute appendicitis.

  • Ileocecal junction – terminal ileitis (infectious, Crohn’s disease), irritable bowel syndrome.

  • Cecum – cecal volvulus and intestinal obstruction, cecal perforation.

Other common etiologies:

  • Proximal ascending colon –

    ◦ Colitis (infectious or inflammatory bowel disease)

    ◦ Intestinal obstruction

    ◦ Right sided diverticulitis and diverticular abscess (rare)

    ◦ Colonic perforation

    ◦ Colonic mass

  • Right kidney (lower pole) and ureter – nephrolithiasis (ureteric colic)

  • In females (gynecologic) –

    ◦ Right ovary – ovarian cyst rupture, ovarian torsion, endometriosis

    ◦ Right fallopian tube – acute pelvic inflammatory disease (salpingitis, tubo-ovarian abscess) and ruptured ectopic pregnancy

  • Retroperitoneal – iliopsoas abscess/hematoma


  • Mesenteric ischemia

  • Mesenteric adenitis

  • Vasculitis – Behcet’s, SLE, polyarteritis nodosa

Extra-abdominal causes
  • Femoral hernias – occur through the femoral canal inferior to the inguinal ligament and can cause referred pain to the RLQ.

  • Communicating scrotal hydrocele

  • Right hip pathology – osteoarthritis, intertrochanteric or acetabular fracture can cause referred pain to RLQ.

  • Pubic ramus fracture

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

History taking

Differentiate acute versus chronic pain.

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

Age, gender, prior abdominal surgical history and abdominal medical history is important. Note any prior history of appendectomy, bowel surgery (e.g. hemicolectomy, adhesiolysis) and in females prior history of salpingo-oopherectomy. Note any history of chronic GI/GU problems such as Crohn’s disease/ulcerative colitis, diverticulitis, history of hernias or nephrolithiasis.

In elderly patients, keep a high index of suspicion for vascular causes such as mesenteric ischemia or aortic aneurysm rupture.

Physical examination
  • Establish severity of the problem with a particular focus on ruling out an “acute surgical abdomen”. Look for presence of “peritoneal signs” (see physical exam below).

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

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

  • Data – check relevant labs and order appropriate abdominal imaging (Kidney scan [KUB] or computed tomography [CT] abdomen and pelvis)

  • An upright or decubitus 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’s a quick way of looking for evidence of “free air under the diaphragm” if a cecal or colonic perforation is suspected or looking for air-fluid levels and distended bowel loops if obstruction is suspected. A KUB may also pick up a radio-opaque ureteric stone.

  • If there is any concern for acute mesenteric ischemia or evidence of an acute abdomen with peritoneal signs in the hospital setting would directly go to a CT abdomen for imaging.

  • 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 had the RLQ pain?

Acuity, intensity and duration of pain may be helpful in assessing severity of disease. A sudden onset of pain suggests a serious intra-abdominal event such as an organ perforation (appendiceal rupture, colonic diverticular perforation) or Ischemia (ischemic colitis) or obstruction of a small tubular structure (ureteric stone).

A more gradual onset of symptoms suggests an infectious or inflammatory cause (Crohn’s disease or gastroenteritis), or obstruction of a large tubular structure (colonic obstruction).

2. Has the pain changed location?

The pain of acute appendicitis may start in the periumbilical area (visceral pain) and then a few hours later localize in the RLQ as the peritoneum overlying the inflamed appendix gets affected (parietal pain).

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

Rule out trauma as the cause of pain.

4. Have you ever had this problem before?

A positive response would suggest a chronic intermittent problem e.g. inflammatory bowel disease (IBD), diverticulitis, nephrolithiasis.

5. Any history of diverticulitis, Crohn’s disease or ulcerative colitis, hernias or nephrolithiasis? Any family history of IBD? Any prior abdominal surgeries – specifically appendectomy, bowel surgery (e.g. hemicolectomy, adhesiolysis) and in females prior history of salpingo-oopherectomy?

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

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

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

May indicate intestinal obstruction or colitis.

7. Does it radiate to the groin or testes(in male), or labia(in females)?

A pain pattern seen in ureteric colic.

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

Postprandial pain of chronic mesenteric ischemia.

9. Does movement make it worse? Does coughing aggravate the pain?

Points to possibility of peritonitis.

10. Does defecation relieve the pain?

A positive response suggests IBD.

11. Any associated nausea or vomiting?

Though a non-specific complaint, in the presence of abdominal distension and constipation may indicate intestinal obstruction.

12. Any fever or chills?

Not specific but puts infectious and inflammatory conditions higher on the list (acute appendicitis, diverticulitis, IBD and in females pelvic inflammatory disease).

13. Any diarrhea?

If yes, then any recent antibiotic use within the past 6-8 weeks or recent consumption of restaurant or stale food? Think C. difficile enterocolitis or other infectious colitis.

14. 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.

15. Any change in bowel habits or stool consistency?

Think colon carcinoma if patient elderly.

16. Any black or maroon 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.

17. Any hematuria, urinary frequency or dysuria?

May be indicative of nephrolithiasis.

Additional questions in female patients if appropriate (patient in reproductive age group and/or reproductive anatomy intact):

18. Any vaginal bleeding or foul smelling vaginal discharge?

Presence of bleeding raises suspicion for possible ectopic pregnancy and a discharge may indicate pelvic inflammatory disease (PID).

19. Are you sexually active? Do you use any form of contraception particularly an IUD?

When was your last menstrual period? Any history of ectopic pregnancies or prior miscarriages?

Focus on risk factors associated with PID or ectopic pregnancies.

20. Have you lost any weight? If so, how much over how long?

This may be a harbinger of a malignancy e.g. colon cancer or a chronic GI illness such as IBD.

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

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

  • Inspect the RLQ.

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

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

  • Make note of any old surgical scars:

    Typical scars found in this location would be an open appendectomy incision (at McBurney’s point – junction of the lateral 1/3rd and medial 2/3rd of the spino-umbilical line in the RLQ) or a small scar from a prior laparoscopic appendectomy.

    The anterior portion of a nephrectomy scar as it wraps around the Right flank.

    Other scars to look for in females would be in the midline and suprapubic area from a prior hysterectomy and salpingo-oophorectomy.

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

  • Look for any obvious swelling or fullness in the RLQ (asymmetric abdominal enlargement) – suggests an abdominal wall mass or intra-abdominal mass.

  • Look for any inguinal or inguinoscrotal(in males) swelling – suggestive of an inguinal or femoral hernia.

  • Palpate the RLQ with the flat of your hand – 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” 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.

  • Hernias: signs of strangulation – redness, tenderness, loss of cough impulse and irreducibility.

Carnett's sign:
  • To confirm the abdominal wall as a cause of pain as opposed to an intra-abdominal organ palpate and find point of maximum tenderness.

  • While palpating with abdomen relaxed have patient tense abdominal wall by doing half a sit-up with the arms crossed or by having them flex their neck to make the chin touch the chest.

  • An increase in pain with the abdomen tensed suggests abdominal wall pathology.

Signs in acute apprendicitis
  • Rovsing’s sign: The examiner palpates the left lower quadrant (LLQ) and the test is positive if the patient experiences pain in the RLQ during LLQ palpation or when the examiner releases pressure in the LLQ.

  • Psoas sign: Pain in the RLQ when the right hip joint is passively extended with the patient lying on their left side. Positive in cases of a retrocecal appendix.

  • Obturator sign: Pain elicited when the examiner passively performs internal rotation with the flexed right thigh. May be positive in cases of a pelvic appendix.

NOTE: In limited studies these 3 signs show a low sensitivity of 15%-35% but a high specificity of 85%-95% for acute appendicitis. In addition, note the absence of RLQ tenderness on palpation in cases of “referred pain” from extra-abdominal causes of RLQ pain. Proceed to examine the right hip joint and inguinal area more carefully; point tenderness over these locations suggest hip joint or pubic rami pathology.

Peritoneal signs and symptoms
  • Abdominal pain is the hallmark of peritonitis.

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

  • Patient with peritonitis 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 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.

  • Complete blood count (CBC)

  • Basic metabolic profile

  • Urinalysis

  • KUB

  • CT Scan of abdomen and pelvis

  • Urine pregnancy test and/or quantitative serum β-HCG level (in female patients in reproductive age group and where appropriate)

  • Pelvic ultrasonography – in suspected PID, ovarian torsion or ectopic pregnancy

  • Hip or pelvic X-rays if appropriate

  • Stool studies – fecal leukocytes, SSYC (salmonella, shigella, yersinia, campylobacter), C. Difficile toxin, ova and parasites when appropriate

  • NAAT – Nucleic acid amplification testing for chlamydia and gonorrhea on endocervical mucus swabs in suspected PID

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

Appendix and ileo-cecal junction

Acute appendicitis

  • Most frequently a disease of young and healthy individuals.

  • Acute onset crampy abdominal pain usually begins in periumbilical area and then migrates to RLQ ; in pelvic appendix dysuria, urinary frequency, diarrhea or tenesmus may be prominent symptoms.

  • Nausea and vomiting usually follow the onset of pain.

  • Low-grade temperature; high fever (>39.4°C) may be a sign of a perforated appendix.

  • Exam:

    ◦ McBurney’s point of maximum tenderness – 2/3rds the distance from the umbilicus to the anterior superior iliac spine (in an anteriorly positioned appendix)

    ◦ Obturator sign (+) in pelvic appendix and psoas sign (+) in retrocecal appendix

  • Labs:

    ◦ White blood cels (WBC) may be elevated in approximately 70% patients; 95% will have a left shift

    ◦ Urinalysis – useful for ruling out a urinary tract infection (UTI)

    ◦ Urine β-HCG (pregnancy test) to rule out pregnancy and the possibility of an ectopic gestation.

    ◦ Cervical cultures if PID suspected

  • Imaging of choice – CT abdomen and pelvis (sensitivity 94%, specificity 96%); findings:

    ◦ Thick appendiceal wall (>2mm)

    ◦ Increased appendiceal diameter (>7mm)

    ◦ An appendicolith (seen in 25% cases)

    ◦ A phlegmon or abscess

    ◦ Free fluid

    ◦ Stranding of adjacent fatty tissue

    ◦ Note: Non-visualization of appendix does not exclude appendicitis

    ◦ Note: Air in the appendix or a contrast-filled appendiceal lumen without other abnormalities on CT virtually eliminates a diagnosis of appendicitis.


  • IBD

  • Crohn’s disease:

    ◦ Has a predilection for the distal small intestine, cecum and proximal colon.

    ◦ Patient may present with acute onset severe RLQ pain (active inflammatory disease) and bloody diarrhea or in some cases with acute to subacute colicky and intermittent RLQ pain (obstructive symptoms).

    ◦ Associated presence of perianal disease (skin tags, fissures and fistulas) strongly suggests Crohn’s.

    ◦ Gross rectal bleeding & acute GI bleed is rare.

    ◦ Exam: RLQ tenderness with or without rebound; occasionally a mass may be felt due to partial obstruction in the bowel due to fibrotic stenoses.

    ◦ Labs: may have an elevated WBC with increased bands; increased C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) aid in the diagnosis.

    ◦ Imaging of choice – CT enterography or MR enterography.

    ◦ GI consultation for Ileocolonoscopy.

    ◦ Note: ulcerative colitis usually presents with bloody diarrhea, rectal bleeding, more diffuse abdominal pain and typically a more insidious onset.

Infectious enterocolitis

  • Acute onset of symptoms – abdominal cramping and diarrhea.

  • Distinguish between Inflammatory diarrhea and non-inflammatory diarrhea.

  • Inflammatory diarrhea – bloody, small volume associated with lower quadrant cramps, patients may be febrile and toxic.

  • Non-inflammatory diarrhea – large volume and watery, associated with nausea, vomiting and diffuse abdominal cramps.

  • If fever greater than 103°F, bloody diarrhea, tenesmus, dehydration and toxic appearing further work-up needed.

  • Labs – CBC, Fecal Leukocytes, Test for SSYC, E. coli O157:H7 andC. difficile (if h/o of antibiotic use), ova and parasites.

Irritable bowel syndrome

  • Rome III criteria

    ◦ Recurrent Abdominal pain or discomfort at least 3 days/month in the last 3 months associated with 2 or more of the following:

    ◦ Improvement with defecation

    ◦ Onset associated with a change in frequency of stool

    ◦ Onset associated with a change in form (appearance) of stool

  • Note: be cognizant of certain “red flags” which may warrant further investigation:

    ◦ Blood in the stool

    ◦ Family history of colon cancer, IBD or celiac disease

    ◦ Fever

    ◦ Onset after age 50

    ◦ Night-time symptoms (waking patient from sleep)

    ◦ Chronic diarrhea, severe chronic constipation or recurrent vomiting

    ◦ Travel history to area endemic for parasitic diseases

    ◦ Weight loss

    ◦ Physical exam shows any of the following:

    ▪ Abdominal mass

    ▪ Signs of intestinal obstruction

    ▪ Signs of malabsorption or thyroid dysfunction

    ▪ Anemia

    ▪ Active arthritis

    ▪ Occult or overt blood on rectal exam

    ▪ Dermatitis herpetiformis or pyoderma gangrenosum

Intestinal obstruction (ascending colonic obstruction or cecal volvulus)

  • Acute onset of lower abdominal cramping associated with constipation and/or obstipation.

  • Severe unremitting pain suggests gangrenous bowel.

  • Abdominal distension. Usually occurs over 2-3 days but will be acute in two-thirds patients with colonic volvulus.

  • 3 main causes – 1) colon cancer 2) benign stricture e.g. diverticular stricture 3) volvulus – sigmoid and cecal.

  • Patients with cecal volvulus often have a past history of abdominal surgeries and a history of chronic constipation and laxative use.

  • Nausea and vomiting may be a late symptom with large bowel obstruction.

  • KUB will show a massively dilated cecum with distended loops of small bowel indicating the proximal small bowel obstruction.


Nephrolithiasis – right ureteric colic

  • Acute to subacute onset – may begin with a dull ache in the RLQ and right flank progressing to intense pain which begins to wax and wane and occurs in paroxysms (ureteric colic).

  • Patients may have passed a stone or gravel in urine.

  • As the stone migrates down the renal pelvis and ureter the pain may radiate to the scrotum in males and labia in females.

  • 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 may show evidence of hematuria or pyuria; CBC – may have a leukocytosis; BMP may show an elevated BUN and creatinine if patient dehydrated or there is significant ureteral obstruction.

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

Gynecologic conditions

Ectopic pregnancy

  • Occurs in sexually active women of reproductive age group whether or not they are using contraceptives or have undergone tubal sterilization.

  • Most common symptom – abdominal pain, absence of menses (interval of amenorrhea usually 6 weeks or more) and irregular vaginal bleeding.

  • Before rupture occurs, pain may be vague soreness or colicky and may be generalized or unilateral. Pain intense during rupture of fallopian tube. Other symptoms following rupture – dizziness and urge to defecate.

  • Vaginal bleeding usually characterized as spotting and rarely as heavy as in spontaneous abortion.

  • Signs – abdominal tenderness and adnexal tenderness on bimanual pelvic exam.

  • Labs – decreased hematocrit; quantitative serum β-HCG radioimmunoassay is positive.

  • Diagnosis confirmed by pelvic ultrasonography.

Ovarian or adnexal torsion

  • Occurs most commonly in the reproductive years with the average patient being in their mid-20s.

  • Also a complication of benign ovarian tumors in post-menopausal women.

  • Pregnancy predisposes women to torsion with an incidence of 1 in 5 women being pregnant when the condition is diagnosed.

  • Typically patient presents with acute onset severe unilateral lower quadrant abdominal pain.

  • Commonly associated with nausea and vomiting.

  • Fever and leukocytosis develop if ovarian necrosis sets in.

  • Pelvic exam will reveal a severely tender adnexal mass.

  • The diagnosis can be confirmed by pelvic vaginal ultrasonography.

Pelvic inflammatory disease (acute)

  • Sexually active female patient.

  • Lower abdominal discomfort associated with mucopurulent vaginal discharge.

  • Lower abdominal tenderness on exam or on pelvic exam evidence of cervical motion tenderness, or adnexal tenderness.

  • Fever, leukocytosis, elevated ESR and CRP.

III. Management while the Diagnostic Process is Proceeding

A. Management of right-lower 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 RLQ pain. If any history of such obtain CT abdomen to rule out intra-abdominal traumatic bowel injury and/or 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 GI Bleed (melena or stool occult blood positive) consider possibility of mesenteric ischemia.

If evidence or suspicion of Peritonitis suspect :

◦ A perforated viscus (inflamed appendix rupture or colonic perforation) or

◦ Intra-abdominal ischemiaI infarction such as in prolonged intestinal obstruction or ovarian infarction in case of prolonged torsion.

If toxic appearing female patient with high fever, chills and mucopurlent vaginal discharge suspect – PID.

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 and metronidazole + diflucan and consult surgery urgently.

◦ Order appropriate abdominal imaging after the above initiated.

◦ Consult appropriate service (surgery or OB/GYN) early

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 systemic 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.

The pregnant

Due to the presence of the gravid uterus, the intra-abdominal anatomy is somewhat temporarily distorted and certain acute abdominal syndromes may not present in the same fashion as they would in the non-pregnant state. For example in pregnancy, the appendix may be displaced cephalad and consequently the signs of peritoneal irritation may not be seen at McBurney’s point in the RLQ. Physicians should be aware of such possibilities when evaluating abdominal pain in the pregnant patient.

What's the evidence?

Press, SM, Smith, AD. “Urology Incidence of negative hematuria in patients with acute urinary lithiasis presenting to the emergency room with flank pain”. Urology. vol. 45. 1995. pp. 753

Kobayashi, T, Nishizawa, K, Mitsumori, K, Ogura, K. “Impact of date of onset on the absence of hematuria in patients with acute renal colic.”. J Urol. vol. 170. 2003. pp. 1093