Symptom Finder - Right Lower Quadrant Pain
Right Lower Quadrant Pain
Most cases of acute RLQ pain are considered appendicitis until proven otherwise, but every physician has been fooled by this axiom more times than he or she would like to remember. For this reason, the astute clinician will want to have a good list of possibilities in mind. Anatomy is the key to recalling an inclusive list of causes of all RLQ pain. Visualizing the structures, layer by layer, one finds the skin and abdominal wall in the first layer; the terminal ileum, cecum, appendix, and Meckel diverticulum in the second layer; the ureters, tubes, and ovaries (in women) in the third layer; and the muscles, spine, and terminal aorta in the fourth layer. Now the organs can be cross-indexed with the various etiologies that may be encountered by using the mnemonic VINDICATE The following discussion emphasizes the most important diseases in the
differential diagnosis.
1. Skin and abdominal wall: Herpes zoster, cellulitis, contusion, and especially inguinal or femoral hernias are significant causes of RLQ pain.
2. Appendix: Appendicitis is a major cause of RLQ pain.
3. Terminal ileum: Regional ileitis, tuberculosis, or typhoid and intussusceptions may involve the ileum and cause severe pain. Mesenteric adenitis and infarcts may also affect the ileum.
4. Cecum: Diverticulitis, colitis (e.g., granulomatous or amebic), and colon carcinoma are culprits that may cause RLQ pain originating in the cecum. Impacted feces are also a possible cause.
5. Meckel diverticulum: This congenital anomaly may become obstructed and inflamed, develop a pancreatitis or a perforated peptic ulcer, or communicate with a periumbilical cellulitis. All of these may cause RLQ pain.
6. Ureters: Renal calculi and hydronephrosis may cause RLQ pain.
7. Ovary and fallopian tubes: A mumps oophoritis may cause pain in the RLQ. Ovarian cysts may twist on their pedicles or rupture, causing pain, as may the rupture of a small graafian follicle in the normal cycle (mittelschmerz). Three significant lesions may
involve the tube: salpingitis, endometriosis, and ectopic pregnancy. All three are painful.
8. Aorta: Dissecting aneurysms or emboli of the terminal aorta and its branches may seize the patient with acute pain.
9. Pelvis and spine: Osteoarthritis, ruptured disc, metastatic carcinoma, Pott disease, and rheumatoid spondylitis should be considered here.
10. Miscellaneous structures: A ruptured peptic ulcer or inflamed gallbladder may leak fluid into the right colic gutter and cause RLQ pain. Any of the numerous causes of intestinal obstruction (e.g., adhesions or volvulus) may cause pain. Omental infarcts are another miscellaneous cause. Referred pain from pneumonia or pulmonary infarct has encouraged some surgeons to insist on a chest x-ray prior to surgery.
Table
Approach to the Diagnosis
Obviously, acute RLQ pain is suspected to be acute appendicitis until proven otherwise. Now abdominal ultrasound or CT scan can establish the diagnosis before surgery in over 90% of cases. However, it is wise to order flat plate and upright films of the abdomen, CBC, urinalysis, and an amylase level before surgery to dodge a curveball. Some surgeons want a chest x-ray as well, because pneumonia and other chest conditions can present with RLQ pain. A pregnancy test should be ordered for women of childbearing age to help rule out a ruptured ectopic pregnancy, but ultrasonography is even better. Surprisingly, many patients get to the operating room without a rectal or vaginal examination. RLQ pain in a child less than 2 years old should be considered intussusceptions until proven otherwise. In cases of chronic RLQ pain, contrast studies such as a barium enema, IVP, upper GI series, and cholecystogram may be indicated. If these are not diagnostic, further investigation with colonoscopy, cystoscopy, culdoscopy, or laparoscopy may be needed. A CT scan of the abdomen and pelvis can often reveal the diagnosis.
Other Useful Tests
1. Stool for occult blood (mesenteric thrombosis, neoplasm)
2. Stool for ova and parasites
3. Gallium or indium scan (diverticulitis, abscess)
4. CT angiography or catheter angiogram (mesenteric thrombosis)
5. X-ray of lumbar spine (herniated disc, etc.)
6. Urine culture, sensitivity, and colony count
7. Chemistry panel
8. Sedimentation rate (inflammation)
9. Lymphangiogram (Hodgkin lymphoma)
10. Urine porphobilinogen (porphyria)
11. Small-bowel series (Meckel diverticulum)
12. Blood lead level
13. Capsule endoscopy (small bowel lesion)
Most cases of acute RLQ pain are considered appendicitis until proven otherwise, but every physician has been fooled by this axiom more times than he or she would like to remember. For this reason, the astute clinician will want to have a good list of possibilities in mind. Anatomy is the key to recalling an inclusive list of causes of all RLQ pain. Visualizing the structures, layer by layer, one finds the skin and abdominal wall in the first layer; the terminal ileum, cecum, appendix, and Meckel diverticulum in the second layer; the ureters, tubes, and ovaries (in women) in the third layer; and the muscles, spine, and terminal aorta in the fourth layer. Now the organs can be cross-indexed with the various etiologies that may be encountered by using the mnemonic VINDICATE The following discussion emphasizes the most important diseases in the
differential diagnosis.
1. Skin and abdominal wall: Herpes zoster, cellulitis, contusion, and especially inguinal or femoral hernias are significant causes of RLQ pain.
2. Appendix: Appendicitis is a major cause of RLQ pain.
3. Terminal ileum: Regional ileitis, tuberculosis, or typhoid and intussusceptions may involve the ileum and cause severe pain. Mesenteric adenitis and infarcts may also affect the ileum.
4. Cecum: Diverticulitis, colitis (e.g., granulomatous or amebic), and colon carcinoma are culprits that may cause RLQ pain originating in the cecum. Impacted feces are also a possible cause.
5. Meckel diverticulum: This congenital anomaly may become obstructed and inflamed, develop a pancreatitis or a perforated peptic ulcer, or communicate with a periumbilical cellulitis. All of these may cause RLQ pain.
6. Ureters: Renal calculi and hydronephrosis may cause RLQ pain.
7. Ovary and fallopian tubes: A mumps oophoritis may cause pain in the RLQ. Ovarian cysts may twist on their pedicles or rupture, causing pain, as may the rupture of a small graafian follicle in the normal cycle (mittelschmerz). Three significant lesions may
involve the tube: salpingitis, endometriosis, and ectopic pregnancy. All three are painful.
8. Aorta: Dissecting aneurysms or emboli of the terminal aorta and its branches may seize the patient with acute pain.
9. Pelvis and spine: Osteoarthritis, ruptured disc, metastatic carcinoma, Pott disease, and rheumatoid spondylitis should be considered here.
10. Miscellaneous structures: A ruptured peptic ulcer or inflamed gallbladder may leak fluid into the right colic gutter and cause RLQ pain. Any of the numerous causes of intestinal obstruction (e.g., adhesions or volvulus) may cause pain. Omental infarcts are another miscellaneous cause. Referred pain from pneumonia or pulmonary infarct has encouraged some surgeons to insist on a chest x-ray prior to surgery.
Table
Approach to the Diagnosis
Obviously, acute RLQ pain is suspected to be acute appendicitis until proven otherwise. Now abdominal ultrasound or CT scan can establish the diagnosis before surgery in over 90% of cases. However, it is wise to order flat plate and upright films of the abdomen, CBC, urinalysis, and an amylase level before surgery to dodge a curveball. Some surgeons want a chest x-ray as well, because pneumonia and other chest conditions can present with RLQ pain. A pregnancy test should be ordered for women of childbearing age to help rule out a ruptured ectopic pregnancy, but ultrasonography is even better. Surprisingly, many patients get to the operating room without a rectal or vaginal examination. RLQ pain in a child less than 2 years old should be considered intussusceptions until proven otherwise. In cases of chronic RLQ pain, contrast studies such as a barium enema, IVP, upper GI series, and cholecystogram may be indicated. If these are not diagnostic, further investigation with colonoscopy, cystoscopy, culdoscopy, or laparoscopy may be needed. A CT scan of the abdomen and pelvis can often reveal the diagnosis.
Other Useful Tests
1. Stool for occult blood (mesenteric thrombosis, neoplasm)
2. Stool for ova and parasites
3. Gallium or indium scan (diverticulitis, abscess)
4. CT angiography or catheter angiogram (mesenteric thrombosis)
5. X-ray of lumbar spine (herniated disc, etc.)
6. Urine culture, sensitivity, and colony count
7. Chemistry panel
8. Sedimentation rate (inflammation)
9. Lymphangiogram (Hodgkin lymphoma)
10. Urine porphobilinogen (porphyria)
11. Small-bowel series (Meckel diverticulum)
12. Blood lead level
13. Capsule endoscopy (small bowel lesion)