Diagnosis of angiodysplasia is often accomplished with endoscopy, either colonoscopy or esophagogastroduodenoscopy (EGD). Although the lesions can be notoriously hard to find, the patient usually is diagnosed by endoscopy. A new technique, pill enteroscopy, has been a major advance in diagnosis, especially in the small bowel which is difficult to reach with traditional endoscopy. With this technique a pill that contains a video camera and radio transmitter is swallowed, and pictures of the small intestine are sent to a receiver worn by the patient. Recently, multiphase CT angiography (without positive oral contrast) has been shown to play a promising role in the diagnoses of small and large bowel angiodysplasia, especially when associated with active hemorrhage

Angiodysplasiae in the small bowel can also be diagnosed and treated with double-balloon enteroscopy, a technique involving a long endoscopic camera and overtube, both fitted with balloons, that allow the bowel to be accordioned over the camera.

In cases with negative endoscopic findings and high clinical suspicion, selective angiography of the mesenteric arteries is sometimes necessary, but this allows for interventions at time of the procedure. An alternative is scintigraphy with red blood cells labeled with a radioactive marker; this shows the site of the bleeding on a gamma camera but tends to be unhelpful unless the bleeding is continuous and significant.

Diagnosis of gastric varices is often made at the time of upper endoscopy.

The Sarin classification of gastric varices identifies four different anatomical types of gastric varices, which differ in terms of treatment modalities.

Initial treatment of bleeding from gastric varices focuses on resuscitation, much as with esophageal varices. This includes administration of fluids, blood products, and antibiotics.

The results from the only two randomized trials comparing band ligation vs cyanoacrylate suggests that endoscopic injection of cyanoacrylate, known as gastric variceal obliteration or GVO is superior to band ligation in preventing rebleeding rates. Cyanoacrylate, a common component in 'super glue' is often mixed 1:1 with lipiodol to prevent polymerization in the endoscopy delivery optics, and to show on radiographic imaging. GVO is usually performed in specialized therapeutic endoscopy centers. Complications include sepsis, embolization of glue, and obstruction from polymerization in the lumen of the stomach.

Other techniques for refractory bleeding include:

- Transjugular intrahepatic portosystemic shunts (TIPS)

- Balloon occluded retrograde transvenous obliteration techniques (BORTO)

- Gastric variceal ligation, although this modality is falling out of favour

- Intra-gastric balloon tamponade as a bridge to further therapy

- a caveat is that a larger balloon is required to occupy the fundus of the stomach where gastric varices commonly occur

- Liver transplantation

The diagnosis of hemosuccus pancreaticus can be difficult to make. Most patients who develop bleeding in the gastrointestinal tract have endoscopic procedures done to visualize the bowel in order to find and treat the source of the bleeding. With hemosuccus, the bleeding is coming from the pancreatic duct which enters into the first part of the small intestine, termed the duodenum. Typical gastroscopes used to visualize the esophagus, stomach and duodenum are designed with fiber-optic illumination that is directed in the same direction as the endoscope, meaning that visualization is in the forward direction. However, the pancreatic duct orifice is located on the side of the duodenum, meaning that it can be missed on forward-viewing endoscopy. A side-viewing endoscope (known as a "duodenoscope", or "side-viewer") used for endoscopic retrograde cholangiopancreatography (ERCP), a procedure to visualize the bile ducts and pancreatic duct on fluoroscopy, can be used to localize the bleeding to the pancreatic duct. It can be confused with bleeding from the common bile duct on endoscopy, leading to the term "pseudohematobilia".

Liver function test is normal apart from an increased serum bilirubin in the event of pancreaticobiliary reflux. Serum amylase is normal outside episodes of acute pancreatitis. It is difficult to diagnose HP because the bleeding is usually intermittent. Endoscopy is essential in ruling out other causes of upper gastrointestinal bleeding and in rare cases; active bleeding can be seen from the duodenal ampulla. Even though endoscopy may be normal, it helps to rule out other causes of upper digestive bleeding (erosive gastritis, peptic ulcers, and oesophageal and gastric fundus varices, etc.). Ultrasonography can be used to visualize pancreatic pseudocysts or aneurysm of the peripancreatic arteries. Doppler ultrasound or dynamic ultrasound has been reported to be diagnostic. Contrast-enhanced CT is an excellent modality for demonstrating the pancreatic pathology and can also demonstrate features of chronic pancreatitis, pseudocysts, and pseudoaneurysms. On precontrast CT, the characteristic finding of clotted blood in the pancreatic duct, known as the sentinel clot, is seldom seen. Computed tomography may show simultaneous opacification of an aneurysmal artery and pseudocyst or persistence of contrast within a pseudocyst after the arterial phase. Again, these findings are only suggestive of the diagnosis. Ultimately, angiography is the diagnostic reference standard. Angiography identifies the causative artery and allows for delineation of the arterial anatomy and therapeutic intervention.

If the anemia is severe, blood transfusion is required before any other intervention is considered. Endoscopic treatment is an initial possibility, where cautery or argon plasma coagulation (APC) treatment is applied through the endoscope. Failing this, angiography and emolization with particles is another microinvasive treatment option, which avoids the need for surgery and bowel resection. Here, the vessel supplying the angiodysplasia is selectively catheterized and embolizaed with microparticles. Resection of the affected part of the bowel may be needed if the other modalities fail. However, the lesions may be widespread, making such treatment impractical.

If the bleeding is from multiple or inaccessible sites, systemic therapy with medication may be necessary. First-line options include the antifibrinolytics tranexamic acid or aminocaproic acid. Estrogens can be used to stop bleeding from angiodysplasia. Estrogens cause mild hypercoaguability of the blood. Estrogen side effects can be dangerous and unpleasant in both sexes. Changes in voice and breast swelling is bothersome in men, but older women often report improvement of libido and perimenopausal symptoms. (The worries about hormone replacement therapy/HRT, however, apply here as well.)

In difficult cases, there have been positive reports about octreotide and thalidomide.

In severe cases or cases not responsive to either endoscopic or medical treatment, surgery may be necessary to arrest the bleeding.

Nutcracker syndrome can be diagnosed with:

- Left renal venography—considered to be the gold standard test.

- Computed tomography (CT).

- Abdominal ultrasonography—not definitive but has been found to be useful.

In emergency situations, care is directed at stopping blood loss, maintaining plasma volume, correcting disorders in coagulation induced by cirrhosis, and appropriate use of antibiotics such as quinolones or ceftriaxone. Blood volume resuscitation should be done promptly and with caution. The goal should be hemodynamic stability and hemoglobin of over 8 g/dl. Resuscitation of all lost blood leads to increase in portal pressure leading to more bleeding. Volume resuscitation can also worsen ascites and increase portal pressure. (AASLD guidelines)

Therapeutic endoscopy is considered the mainstay of urgent treatment. The two main therapeutic approaches are variceal ligation or banding and sclerotherapy.

In cases of refractory bleeding, balloon tamponade with a Sengstaken-Blakemore tube may be necessary, usually as a bridge to further endoscopy or treatment of the underlying cause of bleeding (usually portal hypertension). Esophageal devascularization operations such as the Sugiura procedure can also be used to stop complicated variceal bleeding. Methods of treating the portal hypertension include: transjugular intrahepatic portosystemic shunt, or a distal splenorenal shunt procedure or a liver transplantation.

Nutritional supplementation is not necessary if the patient is not eating for four days or less.

Terlipressin and octreotide for 1 to 5 days have also been used.

Dilated submucosal veins are the most prominent histologic feature of esophageal varices. The expansion of the submucosa leads to elevation of the mucosa above the surrounding tissue, which is apparent during endoscopy and is a key diagnostic feature. Evidence of recent variceal hemorrhage includes necrosis and ulceration of the mucosa. Evidence of past variceal hemorrhage includes inflammation and venous thrombosis.

Treatment of hemosuccus pancreaticus depends on the source of the hemorrhage. If the bleeding is identified on angiography to be coming from a vessel that is small enough to occlude, embolization through angiography may stop the bleeding. Both coils in the end-artery and stents across the area of bleeding have been used to control the hemorrhage. However, the bleeding may be refractory to the embolization, which would necessitate surgery to remove the pancreas at the source of hemorrhage. Also, the cause of bleeding may be too diffuse to be treated with embolization (such as with pancreatitis or with pancreatic cancer). This may also require surgical therapy, and usually a distal pancreatectomy, or removal of the part of the pancreas from the area of bleeding to the tail, is required.

Unlike oesophageal varices, rectal varices are less prone to bleeding, are less serious when a bleed does occur, and are easier to treat because of the more accessible location.

Typically, treatment consists of addressing the underlying portal hypertension. Some treatments include portosystemic shunting, ligation, and under-running suturing. Insertion of a transjugular intrahepatic portosystemic shunt (TIPS) has been shown to alleviate varices caused by portal hypertension. Successful treatment of portal hypertension that subsequently reduces anorectal varices provides a confirmation of the initial diagnosis, allowing for a distinction between varices and hemorrhoids, which would not have been alleviated by reduction of portal hypertension.

Since it is a rare disease, it remains a diagnosis of exclusion of other conditions with similar symptoms. The diagnosis is supported by the results of imaging studies such as computed tomography or magnetic resonance imaging, ultrasound of the abdomen (with or without doppler imaging) or intravenous urography.

Specialist vascular ultrasonographers should routinely look for left ovarian vein reflux in patients with lower limb varices especially if not associated with long or short saphenous reflux. The clinical pattern of varices differs between the two types of lower limb varices.

CT scanning is used to exclude abdominal or pelvic pathology. CT-Angiography/Venography can often demonstrate left ovarian vein reflux and image an enlarged left ovarian vein but is less sensitive and much more expensive than duplex Doppler ultrasound examination. Ultrasound requires that the ultrasonographer be experienced in venous vascular ultrasound and so is not always readily available. A second specialist ultrasound exam remains preferable to a CT scan.

As a wide range of pelvic and abdominal pathology can cause symptoms consistent with those symptoms due to left ovarian vein reflux, prior to embolisation of the left ovarian vein, a careful search for such diagnoses is essential. Consultation with general surgeons, gynaecologists, and possibly CT scanning should always be considered.

Portal hypertensive gastropathy can also be treated with endoscopic treatment delivered through a fibre-optic camera into the stomach. Argon plasma coagulation and electrocautery have both been used to stop bleeding from ectatic vessels, and to attempt to obliterate the vessels, but have limited utility if the disease is diffuse.

Transjugular intrahepatic portosystemic shunt procedures, or TIPS involve decompressing the portal vein by shunting a portal venule to a lower pressure systemic venule, under guidance with fluoroscopy. Since it treats the root cause of portal hypertension gastropathy, it has been putatively used for the condition. The literature reports suggest both regression of portal hypertensive gastropathy on endoscopic images and improvement in bleeding after TIPS.

Finally, cryotherapy involves the use of pressurized carbon dioxide administered through the endoscope to freeze and destroy tissue in a focal area. It is being studied for the treatment of portal hypertensive gastropathy.

When Budd–Chiari syndrome is suspected, measurements are made of liver enzyme levels and other organ markers (creatinine, urea, electrolytes, LDH).

Budd–Chiari syndrome is most commonly diagnosed using ultrasound studies of the abdomen and retrograde angiography. Ultrasound may show obliteration of hepatic veins, thrombosis or stenosis, spiderweb vessels, large collateral vessels, or a hyperechoic cord replacing a normal vein. Computed tomography (CT) or magnetic resonance imaging (MRI) is sometimes employed although these methods are generally not as sensitive. Liver biopsy is nonspecific but sometimes necessary to differentiate between Budd–Chiari syndrome and other causes of hepatomegaly and ascites, such as galactosemia or Reye's syndrome.

In regards to the diagnosis of idiopathic sclerosing mesenteritis, a CT scan which creates cross-section pictures of the affected individuals body, can help in the assessment of the condition.

Several treatment options have been developed for portal hypertensive gastropathy. The first is the use of beta-blockers, which reduce portal pressures. Non-selective beta blockers (such as propranolol and nadolol) have been used to decrease the pressure of the portal vein in patients with esophageal varices, and have been shown to regress portal hypertensive gastropathy that has been worsened by medical treatment of varices. Propranolol has also been evaluated in patients with chronic cirrhosis and portal hypertensive gastropathy. Other medications that primarily treat bleeding, including anti-fibrinolytic medications such as tranexamic acid have also been used in case reports of patients with portal hypertensive gastropathy. These medications work by stabilizing deposits of fibrin at sites that ordinarily would bleed.

Finally, octreotide, an analogue of somatostatin that leads to vasoconstriction of the portal circulation, can be used for active bleeding due to portal hypertensive gastropathy. Sucralfate, a coating medication has also been used, but evidence is from animal models.

Diagnosis is very difficult, and usually one of exclusion. SMA syndrome is thus considered only after patients have undergone an extensive evaluation of their gastrointestinal tract including upper endoscopy, and evaluation for various malabsorptive, ulcerative and inflammatory instestinal conditions with a higher diagnostic frequency. Diagnosis may follow x-ray examination revealing duodenal dilation followed by abrupt constriction proximal to the overlying SMA, as well as a delay in transit of four to six hours through the gastroduodenal region. Standard diagnostic exams include abdominal and pelvic computed tomography (CT) scan with oral and IV contrast, upper gastrointestinal series (UGI), and, for equivocal cases, hypotonic duodenography. In addition, vascular imaging studies such as ultrasound and contrast angiography may be used to indicate increased bloodflow velocity through the SMA or a narrowed SMA angle.

Despite multiple case reports, there has been controversy surrounding the diagnosis and even the existence of SMA syndrome since symptoms do not always correlate well with radiologic findings, and may not always improve following surgical correction. However, the reason for the persistence of gastrointestinal symptoms even after surgical correction in some cases has been traced to the remaining prominence of reversed peristalsis in contrast to direct peristalsis.

Since females between the ages of 10 and 30 are most frequently afflicted, it is not uncommon for physicians to initially and incorrectly assume that emaciation is a choice of the patient instead of a consequence of SMA syndrome. Patients in the earlier stages of SMA syndrome often remain unaware that they are ill until substantial damage to their health is done, since they may attempt to adapt to the condition by gradually decreasing their food intake or naturally gravitating toward a lighter and more digestible diet.

Treatment depends on the severity and symptoms. Treatments include:

- Endovascular stenting.

- Renal vein re-implantation.

- Gonadal vein embolization.

A varix (pl. varices) is an abnormally dilated vessel with a tortuous course. Varices usually occur in the venous system, but may also occur in arterial or lymphatic vessels.

Examples of varices include:

- Varicose veins, large tortuous veins usually found on legs

- Sublingual varices

- Esophageal varices, commonly stemming from cirrhosis of the liver, also known as oesophageal varicose

- Gastric varices, commonly stemming from cirrhosis of the liver

- Intestinal varices

- Scrotal varices

- Vulvar varices

- Pelvic varices

- Vesical varices, varicose veins associated with the urinary bladder

- Rectal varices, which can be similar to external haemorrhoids

There is a recent optical test, but it requires endoscopy (see Diagnosis). There are no specific blood tests for ischemic colitis. The sensitivity of tests among 73 patients were:

- The white blood cell count was more than 15,000/mm3 in 20 patients (27%)

- The serum bicarbonate level was less than 24 mmol/L in 26 patients (36%)

Plain X-rays are often normal or show non-specific findings. In a series of 73 patients, plain abdominal radiography (56%) showing colic distension in 53% or a pneumoperitoneum in 3%.

CT scans are often used in the evaluation of abdominal pain and rectal bleeding, and may suggest the diagnosis of ischemic colitis, pick up complications, or suggest an alternate diagnosis.

Endoscopic evaluation, via colonoscopy or flexible sigmoidoscopy, is the procedure of choice if the diagnosis remains unclear. Ischemic colitis has a distinctive endoscopic appearance; endoscopy can also facilitate alternate diagnoses such as infection or inflammatory bowel disease. Biopsies can be taken via endoscopy to provide more information. Visible light spectroscopy, performed using catheters placed through the 5 mm channel of the endoscope, is diagnostic (see Diagnosis).

The terms rectal varices and haemorrhoids are often used interchangeably, but this is not correct. Haemorrhoids occur due to prolapse of the rectal venous plexus and are no more common in patients with portal hypertension than those without. Rectal varices, however, are only found in patients with portal hypertension and are common in conditions such as cirrhosis.

In terms of possible treatment for the condition of idiopathic sclerosing mesenteritis, medications such as corticosteroids, tamoxifen and thalidomide have been used.

Intestinal varices are dilated submucosal veins in the intestine.

One treatment includes a transjugular intrahepatic portosystemic shunt.

The exact incidence of ischemic colitis is difficult to estimate, as many patients with mild ischemia may not seek medical attention. Ischemic colitis is responsible for about 1 in 2000 hospital admissions, and is seen on about 1 in 100 endoscopies. Men and women are affected equally; ischemic colitis is a disease of the elderly, with more than 90% of cases occurring in people over the age of 60.

The tests that are considered to evaluate of the passage of blood in the stool are based on the characteristics of bleeding (color, quantity) and whether or not the person passing blood has a low blood pressure with elevated heart rate, as opposed to normal vital signs. The following tests are combined to determine the causes of the source of bleeding.

- Digital rectal exam (DRE) and fecal occult blood test (FOBT)

- Colonoscopy

- Anoscopy

- Esophagogastroduodenoscopy (EGD)

- Capsule endoscopy

- CT Scan

Melena is defined as dark, tarry stools, often black in color due to partial digestion of the RBCs.

Hematochezia is defined as bright red blood seen in the toilet either inside of, or surrounding the stool.

Hematochezia is typically presumed to come from the lower portion of the GI tract, and the initial steps of diagnosis include a DRE with FOBT, which if positive, will lead to a colonoscopy. If the person has a large amount of blood in their stool, an EGD test may be necessary. If no source of active bleeding is found on these examinations, a capsule endoscopy may be performed, in order to more closely examine the small bowel, which cannot be seen with the other types of studies. With melena, a DRE with FOBT is often also performed, however the suspicion for a source from the upper GI tract is higher, leading first to the use of EGD with the other tests being required if no source is identified. The anoscopy is another type of examination, which can be used along with a colonoscopy, which exams the rectum and distal portion of the descending colon.

Anemia is a common complication of blood in the stool, especially when there is a large amount of blood or bleeding occurs over a long period of time. Anemia is also commonly associated with an iron deficiency, due to the importance of iron in the formation of red blood cells (RBCs). When anemia is diagnosed as a result of blood in the stool, vitamins that are important for RBC formation (folate, vitamin B12, and vitamin C) are frequently prescribed in order to ensure that all the materials are available for those cells that are made.