Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. Making a definitive diagnosis of the cause of abdominal pain can be difficult, because many diseases can result in this symptom. Abdominal pain is a common problem. Most frequently the cause is benign and/or self-limited, but more serious causes may require urgent intervention.
Abdominal pain is traditionally described by its chronicity (acute or chronic), its progression over time, its nature (sharp, dull, colicky), its distribution (by various methods, such as abdominal quadrant (left upper quadrant, left lower quadrant, right upper quadrant, right lower quadrant)) or other methods that divide the abdomen into nine sections), and by characterization of the factors that make it worse, or alleviate it.
The pain associated with the abdomen of inflammation of the parietal peritoneum (the part of the peritoneum lining the abdominal wall) is steady and aching, and worsened by changes in the tension of peritoneum caused by pressure or positional change. It is often accompanied by tension of the abdominal muscles contracting to relieve such tension.
The pain associated with obstruction of a hollow viscus (as opposed to peritoneal and solid organ pain) is often intermittent or "colicky", coinciding with the peristaltic waves of the organ. Such cramps are exactly what is experienced with early acute appendicitis and gastroenteritis and are somewhat relieved by writhing and massage.
The pain associated with abdominal vascular disturbances (thrombosis or embolism) can be sudden or gradual in onset, and can be severe or mild. Pain associated with the rupture of an abdominal aortic aneurysm may radiate to the back, flank, or genitals.
Pain that is felt in the abdomen may be "referred" from elsewhere (e.g., a disease process in the chest may cause pain in the abdomen), and abdominal processes can cause radiated pain elsewhere (e.g., gall bladder pain—in cholecystitis or cholelithiasis—is often referred to the shoulder).
mechanical obstruction of hollow viscera such as the small intestine, the appendix associated with appendicitis, the large intestine (e.g. by intussusception), the biliary tree (e.g. by gallstones), or the ureter (e.g. by urinary calculi)
functional pain, Irritable Bowel Syndrome (affecting up to 20% of the population, IBS is the most common cause of recurrent, intermittent abdominal pain)
reproductive organs (in women): mittelschmerz, torsion of the ovary, ectopic pregnancy,
Recurrent abdominal pain (RAP) occurs in 5–15% of female children 6–19 years old. In a community-based study of middle and high school students, 13–17% had weekly abdominal pain. Using criteria for irritable bowel syndrome (IBS), 14% of high school students and 6% of middle school students fit the criteria for adult IBS. As with other difficult to diagnose chronic medical problems, patients with RAP [Recurrent Abdominal Pain] account for a very large number of office visits and medical resources in proportion to their actual numbers.
When a physician assesses a patient to determine the etiology and subsequent treatment for abdominal pain the patients history of the presenting complaint and physical examination should derive a diagnosis in over 90% of cases.
It is important also for a physician to remember that abdominal pain can be caused by problems outside the abdomen, especially heart attacks and pneumonias which can occasionally present as abdominal pain.
Investigations that would aid diagnosis include
Blood tests including Full Blood Count, Electrolytes, Urea, Creatinine, Liver function tests, pregnancy test and lipase.
Urinalysis
Imaging including erect Chest X-ray and plain films of the abdomen
An electrocardiograph to rule out a heart attack which can occasionally present as abdominal pain
If diagnosis remains unclear after history, examination and basic investigations as above then more advanced investigations may reveal a diagnosis. These as such would include
Computed Tomography of the Abdomen/Pelvis
Abdominal or Pelvic ultrasound
Endoscopy and Colonoscopy (not used for diagnosing acute pain)