Abdominal Pain

Abdominal pain
Other names: Stomach ache, tummy ache, belly ache, belly pain, gut ache
Abdominal pain can be characterized by the region it affects
Specialty	General surgery
Types	Acute, chronic[1]
Causes	Common: Gastroenteritis, irritable bowel syndrome[2] Serious: Appendicitis, perforated stomach ulcer, pancreatitis, ruptured diverticulitis, ovarian torsion, volvulus, ruptured aortic aneurysm, lacerated spleen or liver, ischemic bowel[3]

Abdominal pain, also known as a stomach ache, is a symptom of discomfort anywhere in the abdominal region.^[4] It can be localized in one of the four quadrants or the abdomen or occur diffusely.^[3] Other symptoms such as nausea, vomiting, diarrhea, or constipation may be present.^[3][5] It may be divided into pain of sudden onset (acute) and long term pain (chronic).^[1]

Common causes include gastroenteritis and irritable bowel syndrome.^[2] About 15% of people have a more serious underlying condition such as appendicitis, gall bladder disease, ruptured abdominal aortic aneurysm, perforated peptic ulcer, pancreatitis, ovarian torsion, volvulus, diabetic ketoacidosis, diverticulitis, ischemic bowel, or ectopic pregnancy.^[2][3] In babies necrotizing enterocolitis, vulvulus, and intussuception should be considered.^[3] In a third of cases the exact cause is unclear.^[3]

Diagnosis may be based on the history of symptoms, examination, blood work, and medical imaging.^[3] An ECG may be done to rule out a heart attack.^[3] Treatment may include intravenous fluids and pain management.^[3] Depending on the underlying cause surgery may be required.^[3] About 10% of people in the emergency department are there for abdominal pain.^[3]

Differential diagnosis[edit | edit source]

The most frequent reasons for abdominal pain are gastroenteritis (13%), irritable bowel syndrome (8%), urinary tract problems (5%), inflammation of the stomach (5%) and constipation (5%). In about 30% of cases, the cause is not determined. About 10% of cases have a more serious cause including gallbladder (gallstones or biliary dyskinesia) or pancreas problems (4%), diverticulitis (3%), appendicitis (2%) and cancer (1%).^[2] More common in those who are older, mesenteric ischemia and abdominal aortic aneurysms are other serious causes.^[6]

Sudden onset[edit | edit source]

Acute abdomen can be defined as severe, persistent abdominal pain of sudden onset that is likely to require surgical intervention to treat its cause. The pain may frequently be associated with nausea and vomiting, abdominal distention, fever and signs of shock. One of the most common conditions associated with acute abdominal pain is acute appendicitis.

• Traumatic: blunt or perforating trauma to the stomach, bowel, spleen, liver, or kidney
• Inflammatory:
  • Infections such as appendicitis, cholecystitis, pancreatitis, pyelonephritis, pelvic inflammatory disease, hepatitis, mesenteric adenitis, or a subdiaphragmatic abscess
  • Perforation of a peptic ulcer, a diverticulum, or the caecum
  • Complications of inflammatory bowel disease such as Crohn's disease or ulcerative colitis
• Mechanical:
  • Small bowel obstruction secondary to adhesions caused by previous surgeries, intussusception, hernias, benign or malignant neoplasms
  • Large bowel obstruction caused by colorectal cancer, inflammatory bowel disease, volvulus, fecal impaction or hernia
• Vascular: occlusive intestinal ischemia, usually caused by thromboembolism of the superior mesenteric artery

By system[edit | edit source]

A more extensive list includes the following:^[7]

• Gastrointestinal
  • GI tract
    • Inflammatory: gastroenteritis, appendicitis, gastritis, esophagitis, diverticulitis, Crohn's disease, ulcerative colitis, microscopic colitis
    • Obstruction: hernia, intussusception, volvulus, post-surgical adhesions, tumors, severe constipation, hemorrhoids
    • Vascular: embolism, thrombosis, hemorrhage, sickle cell disease, abdominal angina, blood vessel compression (such as celiac artery compression syndrome), superior mesenteric artery syndrome, postural orthostatic tachycardia syndrome
    • Digestive: peptic ulcer, lactose intolerance, celiac disease, food allergies
  • Glands
    • Bile system
      • Inflammatory: cholecystitis, cholangitis
      • Obstruction: cholelithiasis, tumours
    • Liver
      • Inflammatory: hepatitis, liver abscess
    • Pancreatic
      • Inflammatory: pancreatitis
• Renal and urological
  • Inflammation: pyelonephritis, bladder infection, indigestion
  • Obstruction: kidney stones, urolithiasis, urinary retention, tumours
  • Vascular: left renal vein entrapment
• Gynaecological or obstetric
  • Inflammatory: pelvic inflammatory disease
  • Mechanical: ovarian torsion
  • Endocrinological: menstruation, Mittelschmerz
  • Tumors: endometriosis, fibroids, ovarian cyst, ovarian cancer
  • Pregnancy: ruptured ectopic pregnancy, threatened abortion
• Abdominal wall
  • muscle strain or trauma
  • muscular infection
  • neurogenic pain: herpes zoster, radiculitis in Lyme disease, abdominal cutaneous nerve entrapment syndrome (ACNES), tabes dorsalis
• Referred pain
  • from the thorax: pneumonia, pulmonary embolism, ischemic heart disease, pericarditis
  • from the spine: radiculitis
  • from the genitals: testicular torsion
• Metabolic disturbance
  • uremia, diabetic ketoacidosis, porphyria, C1-esterase inhibitor deficiency, adrenal insufficiency, lead poisoning, black widow spider bite, narcotic withdrawal
• Blood vessels
  • aortic dissection, abdominal aortic aneurysm
• Immune system
  • sarcoidosis
  • vasculitis
  • familial Mediterranean fever
• Idiopathic
  • irritable bowel syndrome (affecting up to 20% of the population, IBS is the most common cause of recurrent, intermittent abdominal pain)

By location[edit | edit source]

The location of abdominal pain can provide information about what may be causing the pain. The abdomen can be divided into four regions called quadrants. Locations and associated conditions include:^[8][9]

• Diffuse
  • Peritonitis
  • Vascular: mesenteric ischemia, ischemic colitis, Henoch-Schonlein purpura, sickle cell disease, systemic lupus erythematosus, polyarteritis nodosa
  • Small bowel obstruction
  • Irritable bowel syndrome
  • Metabolic disorders: ketoacidosis, porphyria, familial Mediterranean fever, adrenal crisis
• Epigastric
  • Heart: myocardial infarction, pericarditis
  • Stomach: gastritis, stomach ulcer, stomach cancer
  • Pancreas: pancreatitis, pancreatic cancer
  • Intestinal: duodenal ulcer, diverticulitis, appendicitis
• Right upper quadrant
  • Liver: hepatomegaly, fatty liver, hepatitis, liver cancer, abscess
  • Gallbladder and biliary tract: inflammation, gallstones, worm infection, cholangitis
  • Colon: bowel obstruction, functional disorders, gas accumulation, spasm, inflammation, colon cancer
  • Other: pneumonia, Fitz-Hugh-Curtis syndrome
• Left upper quadrant
  • Splenomegaly
  • Colon: bowel obstruction, functional disorders, gas accumulation, spasm, inflammation, colon cancer
• Around the belly button
  • Appendicitis
  • Pancreatitis
  • Inferior myocardial infarction
  • Peptic ulcer
  • Diabetic ketoacidosis
  • Vascular: aortic dissection, aortic rupture
  • Bowel: mesenteric ischemia, Celiac disease, inflammation, intestinal spasm, functional disorders, small bowel obstruction
• Lower abdominal pain
  • Diarrhea
  • Colitis
  • Crohn's
  • Dysentery
  • Hernia
• Right lower quadrant
  • Colon: intussusception, bowel obstruction, appendicitis (McBurney's point)
  • Kidney: kidney stone (nephrolithiasis), pyelonephritis
  • Pelvic: cystitis, bladder stone, bladder cancer, pelvic inflammatory disease, pelvic pain syndrome
  • Gynecologic: endometriosis, intrauterine pregnancy, ectopic pregnancy, ovarian cyst, ovarian torsion, fibroid (leiomyoma), abscess, ovarian cancer, endometrial cancer
• Left lower quadrant
  • Bowel: diverticulitis, sigmoid colon volvulus, bowel obstruction, gas accumulation, Toxic megacolon
• Right low back pain
  • Liver: hepatomegaly
  • Kidney: kidney stone (nephrolithiasis), complicated urinary tract infection
• Left low back pain
  • Spleen
  • Kidney: kidney stone (nephrolithiasis), complicated urinary tract infection
• Low back pain
  • kidney pain (kidney stone, kidney cancer, hydronephrosis)
  • Ureteral stone pain

Pathophysiology[edit | edit source]

Region	Blood supply[10]	Innervation[11]	Structures[10]
Foregut	Celiac artery	T5 - T9	Pharynx Esophagus Lower respiratory tract Stomach Proximal duodenum Liver Biliary tract Gallbladder Pancreas
Midgut	Superior mesenteric artery	T10 - T12	Distal duodenum Cecum Appendix Ascending colon Proximal transverse colon
Hindgut	Inferior mesenteric artery	L1 - L3	Distal transverse colon Descending colon Sigmoid colon Rectum Fever Superior anal canal

Abdominal pain can be referred to as visceral pain or peritoneal pain. The contents of the abdomen can be divided into the foregut, midgut, and hindgut.^[10] The foregut contains the pharynx, lower respiratory tract, portions of the esophagus, stomach, portions of the duodenum (proximal), liver, biliary tract (including the gallbladder and bile ducts), and the pancreas.^[10] The midgut contains portions of the duodenum (distal), cecum, appendix, ascending colon, and first half of the transverse colon.^[10] The hindgut contains the distal half of the transverse colon, descending colon, sigmoid colon, rectum, and superior anal canal.^[10]

Each subsection of the gut has an associated visceral afferent nerve that transmits sensory information from the viscera to the spinal cord, traveling with the autonomic sympathetic nerves.^[12] The visceral sensory information from the gut traveling to the spinal cord, termed the visceral afferent, is non-specific and overlaps with the somatic afferent nerves, which are very specific.^[13] Therefore, visceral afferent information traveling to the spinal cord can present in the distribution of the somatic afferent nerve; this is why appendicitis initially presents with T10 periumbilical pain when it first begins and becomes T12 pain as the abdominal wall peritoneum (which is rich with somatic afferent nerves) is involved.^[13]

Diagnostic approach[edit | edit source]

In order to better understand the underlying cause of abdominal pain, one can perform a thorough history and physical examination.

The process of gathering a history may include:^[14]

• Identifying more information about the chief complaint by eliciting a history of present illness; i.e. a narrative of the current symptoms such as the onset, location, duration, character, aggravating or relieving factors, and temporal nature of the pain. Identifying other possible factors may aid in the diagnosis of the underlying cause of abdominal pain, such as recent travel, recent contact with other ill individuals, and for females, a thorough gynecologic history.
• Learning about the patient's past medical history, focusing on any prior issues or surgical procedures.
• Clarifying the patient's current medication regimen, including prescriptions, over-the-counter medications, and supplements.
• Confirming the patient's drug and food allergies.
• Discussing with the patient any family history of disease processes, focusing on conditions that might resemble the patient's current presentation.
• Discussing with the patient any health-related behaviors (e.g. tobacco use, alcohol consumption, drug use, and sexual activity) that might make certain diagnoses more likely.
• Reviewing the presence of non-abdominal symptoms (e.g., fever, chills, chest pain, shortness of breath, vaginal bleeding) that can further clarify the diagnostic picture.

After gathering a thorough history, one should perform a physical exam in order to identify important physical signs that might clarify the diagnosis, including a cardiovascular exam, lung exam, thorough abdominal exam, and for females, a genitourinary exam.^[14]

Additional investigations that can aid diagnosis include:^[15]

• Blood tests including complete blood count, basic metabolic panel, electrolytes, liver function tests, amylase, lipase, troponin I, and for females, a serum pregnancy test.
• Urinalysis
• Imaging including chest and abdominal X-rays
• Electrocardiogram

If diagnosis remains unclear after history, examination, and basic investigations as above, then more advanced investigations may reveal a diagnosis. Such tests include:^[15]

• Computed tomography of the abdomen/pelvis
• Abdominal or pelvic ultrasound
• Endoscopy and/or colonoscopy

Management[edit | edit source]

The management of abdominal pain depends on many factors, including the etiology of the pain. In the emergency department, a person presenting with abdominal pain may initially require IV fluids due to decreased intake secondary to abdominal pain and possible emesis or vomiting.^[16] Treatment for abdominal pain includes analgesia, such as non-opioid (ketorolac) and opioid medications (morphine, fentanyl).^[16] Choice of analgesia is dependent on the cause of the pain, as ketorolac can worsen some intra-abdominal processes.^[16] Patients presenting to the emergency department with abdominal pain may receive a "GI cocktail" that includes an antacid (examples include omeprazole, ranitidine, magnesium hydroxide, and calcium chloride) and lidocaine.^[16] After addressing pain, there may be a role for antimicrobial treatment in some cases of abdominal pain.^[16] Butylscopolamine (Buscopan) is used to treat cramping abdominal pain with some success.^[17] Surgical management for causes of abdominal pain includes but is not limited to cholecystectomy, appendectomy, and exploratory laparotomy.

Emergencies[edit | edit source]

Below is a brief overview of abdominal pain emergencies.

Condition	Presentation	Diagnosis	Management
Appendicitis[18]	Abdominal pain, nausea, vomiting, fever Periumbilical pain, migrates to RLQ	Clinical (history & physical exam) Abdominal CT	Nothing by mouth IV fluids as needed General surgery consultation, possible appendectomy Antibiotics Pain control
Cholecystitis[18]	Abdominal pain (RUQ, radiates epigastric), nausea, vomiting, fever, Murphy's sign	Clinical (history & physical exam) Imaging (RUQ ultrasound) Labs (leukocytosis, transamintis, hyperbilirubinemia)	Patient made NPO (nothing by mouth) IV fluids as needed General surgery consultation, possible cholecystectomy Antibiotics Pain, nausea control
Acute pancreatitis[18]	Abdominal pain (sharp epigastric, shooting to back), nausea, vomiting	Clinical (history & physical exam) Labs (elevated lipase) Imaging (abdominal CT, ultrasound)	Patient made NPO (nothing by mouth) IV fluids as needed Pain, nausea control Possibly consultation of general surgery or interventional radiology
Bowel obstruction[18]	Abdominal pain (diffuse, crampy), bilious emesis, constipation	Clinical (history & physical exam) Imaging (abdominal X-ray, abdominal CT)	Patient made NPO (nothing by mouth) IV fluids as needed Nasogastric tube placement General surgery consultation Pain control
Upper GI bleed[18]	Abdominal pain (epigastric), hematochezia, melena, hematemesis, hypovolemia	Clinical (history & physical exam, including digital rectal exam) Labs (complete blood count, coagulation profile, transaminases, stool guaiac)	Aggressive IV fluid resuscitation Blood transfusion as needed Medications: proton pump inhibitor, octreotide Stable patient: observation Unstable patient: consultation (general surgery, gastroenterology, interventional radiology)
Lower GI Bleed[18]	Abdominal pain, hematochezia, melena, hypovolemia	Clinical (history & physical exam, including digital rectal exam) Labs (complete blood count, coagulation profile, transaminases, stool guaiac)	Aggressive IV fluid resuscitation Blood transfusion as needed Medications: proton pump inhibitor Stable patient: observation Unstable patient: consultation (general surgery, gastroenterology, interventional radiology)
Perforated Viscous[18]	Abdominal pain (sudden onset of localized pain), abdominal distension, rigid abdomen	Clinical (history & physical exam) Imaging (abdominal X-ray or CT showing free air) Labs (complete blood count)	Aggressive IV fluid resuscitation General surgery consultation Antibiotics
Volvulus[18]	Sigmoid colon volvulus: Abdominal pain (>2 days, distention, constipation) Cecal volvulus: Abdominal pain (acute onset), nausea, vomiting	Clinical (history & physical exam) Imaging (abdominal X-ray or CT)	Sigmoid: Gastroenterology consultation (flexibile sigmoidoscopy) Cecal: General surgery consultation (right hemicolectomy)
Ectopic pregnancy[18]	Abdominal and pelvic pain, bleeding If ruptured ectopic pregnancy, patient may present with peritoneal irritation and hypovolemic shock	Clinical (history & physical exam) Labs: complete blood count, urine pregnancy test followed with quantitative blood beta-hCG Imaging: transvaginal ultrasound	If patient is unstable: IV fluid resuscitation, urgent obstetrics and gynecology consultation If patient is stable: continue diagnostic workup, establish OBGYN follow-up
Abdominal aortic aneurysm[18]	Abdominal pain, flank pain, back pain, hypotension, pulsatile abdominal mass	Clinical (history & physical exam) Imaging: Ultrasound, CT angiography, MRA/magnetic resonance angiography	If patient is unstable: IV fluid resuscitation, urgent surgical consultation If patient is stable: admit for observation
Aortic dissection[18]	Abdominal pain (sudden onset of epigastric or back pain), hypertension, new aortic murmur	Clinical (history & physical exam) Imaging: Chest X-Ray (showing widened mediastinum), CT angiography, MRA, transthoracic echocardiogram/TTE, transesophageal echocardiogram/TEE	IV fluid resuscitation Blood transfusion as needed (obtain type and cross) Medications: reduce blood pressure (sodium nitroprusside plus beta blocker or calcium channel blocker) Surgery consultation
Liver injury[18]	After trauma (blunt or penetrating), abdominal pain (RUQ), right rib pain, right flank pain, right shoulder pain	Clinical (history & physical exam) Imaging: FAST examination, CT of abdomen and pelvis Diagnostic peritoneal aspiration and lavage	Resuscitation (Advanced Trauma Life Support) with IV fluids (crystalloid) and blood transfusion If patient is unstable: general or trauma surgery consultation with subsequent exploratory laparotomy
Splenic injury[18]	After trauma (blunt or penetrating), abdominal pain (LUQ), left rib pain, left flank pain	Clinical (history & physical exam) Imaging: FAST examination, CT of abdomen and pelvis Diagnostic peritoneal aspiration and lavage	Resuscitation (Advanced Trauma Life Support) with IV fluids (crystalloid) and blood transfusion If patient is unstable: general or trauma surgery consultation with subsequent exploratory laparotomy and possible splenectomy If patient is stable: medical management, consultation of interventional radiology for possible arterial embolization

Epidemiology[edit | edit source]

Abdominal pain is the reason about 3% of adults see their family physician.^[2] Rates of emergency department visits in the United States for abdominal pain increased 18% from 2006 through 2011. This was the largest increase out of 20 common conditions seen in the ED. The rate of ED use for nausea and vomiting also increased 18%.^[19]

References[edit | edit source]

External links[edit | edit source]

Classification	ICD-10: R10 ICD-9-CM: 789.0 MeSH: D015746 DiseasesDB: 14367
External resources	MedlinePlus: 003120