Various conditions may cause some pain, but primarily cause other more prominent symptoms like vomiting or diarrhea that lead a patient to seek care. Those aren’t addressed here; we’re now dealing with the patient whose main concern is new-onset pain in the lower part of their belly.
Causes of Acute Lower Abdominal / Pelvic Pain
|xRight Lower Quadrant (RLQ)|
• Kidney Stone ?
• Muscle Strain
• Tubal Infection (PID) *
• Ectopic Pregnancy *
• Miscarriage *
• Mittelschmerz / xxxDysmenorrhea (menstrual xxxxxxxpains) *
• Ovarian Disease *
• Testicular Disease ? **
• Herpes Zoster (Shingles)
? = usually in Flank, but also sometimes here
• Bladder Infection (UTI)
• Uterine Infection xxxx(endometritis) *
• Muscle Strain
• Mittelschmerz /
xxxDysmenorrhea (menstrual xxxxxxxpains) *x*****
xxxx* Women only
xxxx** Men only
|xxLeft Lower Quadrant (LLQ)|
• All conditions that cause xxxxxxRLQ pain
NOTE: Some patients we may send right to ER for tests / exam by a surgeon:
- Severe pain and/or tenderness (the abdomen is as hard as a board)
- Fever (unless we diagnose urinary tract infection by symptoms & urinalysis)
- Elderly or Immunocompromised (poor immunity due to other diseases), because they’re more likely to have serious illness with minimal or atypical symptoms
How we Approach New RIGHT Lower Abdominal Pain (in patients not very ill)
1. Think about Appendicitis
- Send to ER if getting progressively worse AND tender to palpation (especially if nausea or vomiting; especially if fever or extremely tender)
- If pain is vague, very subtle tenderness — OK to see what happens during the next day. If gets worse, go to ER
- Symptoms going on for several days or more are NOT appendicitis
2. Women with any possibility at all of being → get a Pregnancy Test
- Using birth control does not mean 100% for sure there’s no pregnancy
- If positive, send to ER to rule out Ectopic Pregnancy or Miscarriage in progress
- ER does Transvaginal Ultrasound, measures blood levels of hCG hormone, and repeats those tests every 3 days if diagnosis uncertain.
3. Non-Pregnant Women — Perform a Pelvic Exam
- Pelvic exam diagnoses PID (Fallopian tube infection) by finding tenderness, esp. if there’s an IUD or risks for STDs. STD test results come back later.
- If moderate-to-severe Tenderness, we may send to ER for Ultrasound to rule out Tubal Abscess and Ovarian Diseases (esp. Ovarian Torsion), particularly if nausea, fever, or we feel a mass.
- No tenderness on exam suggests Mittelschmerz (midcycle pain), Dysmenorrhea if during period (Menstrual Cramps), ruptured Ovarian Cyst (after midcycle), or non-pelvic conditions (see below)
4. Men, and Women without the above conditions
- Look for Hernia if the pain is really in the groin, where we’d find it on groin exam
- Kidney Stone is rarely felt in lower abdomen alone (usually in the flank too). We’d suspect it if sudden onset pain, nausea, no tenderness, and blood on urinalysis.
- Urinary Tract Infection if also urinary symptoms (painful urination, frequent urge to urinate small amounts). We diagnose it with Urinalysis.
- Men might feel Testicular Diseases in the low abdomen, but always in the testicles too
- Herpes Zoster (Shingles) can only be diagnosed once a splotchy red rash appears, usually with some blisters (pain often starts 1-2 days before)
- Muscle Strain is a very common cause of mild low abdominal pain.
- We suspect it if none of the other conditions above seems likely.
- We diagnose it if pain occurs with certain movements, or if we find tenderness to palpation while the patient is tensing the muscles (like doing a sit-up)
How We Approach New LEFT Lower Abdominal Pain (in patients NOT very ill)
The same as for the Right Side [see above], except:
- No appendicitis
- Diverticulitis: usually >50 yrs. old, gradual onset over 3-4 days. Antibiotics may work, but the older or sicker the patient, the better it is to get a CT scan in an ER.
- Constipation: Rarely to blame for a new pain, unless constipation and symptoms began at the same time, and pain is relieved with defecation.
How We Approach New Suprapubic Pain (in patients who don’t look very ill)
The same as for the Right Lower Quadrant [see above], except:
- We don’t consider herpes zoster or kidney stone, and it’s probably not appendicitis.
- If urinary symptoms (painful urination, and frequent urge to urinate small amounts), we obtain a Urinalysis and diagnose Urinary Tract Infection (UTI) if it’s positive
- If no UTI, no hernia, not pregnant, & no gynecological conditions above, probably a Muscle Strain
See Acute Low Abdominal Pain — Full Text for more in-depth explanations and discussions.