Laboratory Tests and Ancillaries
Laboratory Tests
Laboratory tests have
a minimal role in evaluating patients with uncomplicated PUD. A fasting serum
gastrin level may be measured in patients with duodenal ulcers in whom the
presence of other diagnoses (eg Zollinger-Ellison syndrome) is suspected.
H pylori testing is recommended for all patients with PUD for diagnosing and managing concomitant infection and may include rapid
urease test, serologic ELISA (IgG antibody), urea breath test or stool antigen
test. The test and treat strategy is recommended in areas where the H pylori
infection rate is >10% and in patients with past or active PUD, low-grade
gastric mucosa-associated lymphoid tissue (MALT) lymphoma, or a history of endoscopic
resection of early gastric cancer. A routine screening for H pylori in
asymptomatic individuals is not recommended.
Imaging
Diagnostic
Procedures
Esophagogastroduodenoscopy
Esophagogastroduodenoscopy is the diagnostic procedure of choice
in uncomplicated PUD to confirm the diagnosis and to rule out cancer. This identifies gastric
and duodenal ulcers and malignant lesions with 90% sensitivity and specificity.
NSAID-associated ulcers typically present as a shallow, flat, antral ulcer with
associated lesions. This is recommended in patients with evidence of bleeding to allow an accurate
diagnosis and for administration of endoscopic therapy, anemia, >10% weight loss,
chronic PUD, persistent vomiting, or any alarm features that may suggest
significant structural disease or malignancy (eg dysphagia, odynophagia, early
satiety, abdominal mass, lymphadenopathy, weight loss, or history of prior malignancy); in patients whose symptoms
do not respond to pharmacological therapy, and in >50-year-old patients with
new-onset dyspepsia.
Esophagogastroduodenoscopy
may be used for surveillance of ulcers. This should be considered in patients with
duodenal ulcers who have persistent symptoms despite appropriate therapy. This
may rule out refractory peptic ulcers and ulcers with non-peptic origin. This has
low yield if patients’ symptoms resolved after a course of acid suppression with
eradication treatment for H pylori and discontinuation of NSAIDs. Esophagogastroduodenoscopy may
identify gastric cancer early in patients with gastric ulcer, hence improving
survival. This should be performed depending on patients’ risk for gastric
ulcer. This should be considered in patients with gastric ulcer without clear
etiology and in those who did not undergo biopsy during index esophagogastroduodenoscopy. This should
be performed in patients with refractory PUD until the ulcer has healed or the
etiology has been identified.
Esophagogastroduodenoscopy allows biopsy of the lesion. This
is indicated for gastric ulcer with malignant features (eg associated mass
lesion, elevated irregular ulcer borders and abnormal adjacent mucosal folds).
Surveillance esophagogastroduodenoscopy with biopsy is recommended
for gastric ulcers even those without malignant features because of the higher
risk for malignancy. It must be
noted that biopsies should be taken from the margins of gastric ulcers because
of the risk of underlying gastric malignancy. If a duodenal ulcer or gastric
ulcer is identified during esophagogastroduodenoscopy, gastric mucosal biopsies
should be obtained to test for H pylori using histological exam and
culture or rapid urease testing. There is a 3- to 6-fold increased risk for gastric cancer to
develop from H pylori-associated ulcer. Initially, some malignant ulcers
may appear endoscopically benign. Approximately 2-5% of malignant ulcers may have false-negative biopsy
results. Even when
initial gastric ulcer biopsies are benign, repeat esophagogastroduodenoscopy
after about 8 weeks is traditionally performed to document healing, since up to
4% of ulcers that appear benign on initial endoscopy are later found to be
malignant. Ulcers that
are not healed after 8-12 weeks of medical therapy should have a repeat biopsy.
Routine cytologic brushings may add to sensitivity but are not advised as an
alternative or adjunct to endoscopic biopsy.
Peptic Ulcer Disease_Diagnostics 1Esophagogastroduodenoscopy may also be used in diagnosing, prognosticating, and managing complications of PUD. In bleeding PUD, esophagogastroduodenoscopy done within 24 hours of admission has been shown to reduce the need for blood transfusion, shorten intensive care unit (ICU) and hospital stays, decrease the need for surgery, and lower the mortality rate. Patients with features of high risk of rebleeding on endoscopy (eg presence of adherent clots, visible vessels, active arterial bleeding) should undergo endoscopic therapy (ie clips, bipolar electrocoagulation, heater probe, sclerosant) to attain hemostasis and to lower the risk of rebleeding. Endoscopic hemostasis using Epinephrine should be followed by another modality (eg fibrin glue, thrombin, alcohol). Repeat endoscopic therapy is advised prior to considering surgical or radiological intervention in patients who rebleed after initial endoscopic therapy. Esophagogastroduodenoscopy allows identification of ulcer penetration to adjacent organs like the liver and spleen through biopsy obtained via endoscopy. It is important in confirming the presence and distinguishing benign from malignant obstruction. Endoscopic balloon dilation has been used to manage benign gastric outlet obstruction, causing good to excellent short-term relief of symptoms in 67-83% of patients. This is contraindicated in patients with acute perforated peptic ulcer. In some studies, role has been limited in identifying perforation site and in guiding subsequent laparoscopic intercorporeal suture repair with omental patch.
Radiologic Upper Gastrointestinal Series
An upper gastrointestinal series may be an option when esophagogastroduodenoscopy is not available. This can be used for initial assessment in patients with suspected perforation. This is not effective in identifying ulcers <0.5 cm in size and does not allow biopsy.
Abdominal Computed Tomography (CT) Scan
An abdominal CT scan is recommended for diagnosing PUD complications (eg perforation and obstruction). A perforated ulcer will present with free air below the diaphragm on CT scan. This is not sensitive for diagnosing uncomplicated PUD and may miss superficial ulcers.
Peptic Ulcer Disease_Diagnostics 2