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Right-lower quadrant abdominal pain - The Clinical Advisor

Right-lower quadrant abdominal pain
What's the evidence?
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.
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
Inguinal canal - inguinal hernias (specific to the lower abdominal quadrants).
b)
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 r
etroperitoneal)
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:
Ileocecal junction - terminal ileitis (infectious, Crohn's disease), irritable bowel syndrome.
Cecum - cecal volvulus and intestinal obstruction, cecal perforation.
Other common etiologies:
B. Describe a diagnostic approach/method to the patient with this problem
History taking
Differentiate acute versus chronic pain.
Make sure pain is non-traumtic 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.
Diagnostics
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.
Inspection
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.
Palpation
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:
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.
KIDNEY
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 -HCG radioimmunoassay is positive.
Diagnosis confirmed by pelvic ultrasonography.
Ovarian or adnexal torsion