Can a Computed Tomography Angiography (CTA) of the abdomen and pelvis diagnose appendicitis in a patient with right-sided abdominal pain and profuse Gastrointestinal (GI) bleeding?

From the Guidelines

A Computed Tomography Angiography (CTA) of the abdomen and pelvis can still diagnose appendicitis in a patient with right-sided abdominal pain and profuse GI bleeding, as it is capable of detecting not only the appendix but also active bleeding sources. The CTA procedure involves intravenous contrast administration followed by rapid CT scanning, allowing visualization of both vascular structures and inflamed tissues, such as an enlarged appendix, appendiceal wall thickening, periappendiceal fat stranding, and possibly an appendicolith 1. For patients with GI bleeding, CTA can simultaneously detect extravasation of contrast material, indicating active bleeding sites, with a sensitivity and specificity of 85% and 92%, respectively, for the diagnosis of active GIB 1.

Some key points to consider when using CTA for diagnosing appendicitis in patients with GI bleeding include:

• The use of noncontrast images for CTA performed on single-energy CT, which can be replaced by virtual noncontrast reconstructions with dual-energy CT, to detect intraluminal high-attenuation material that may mimic intraluminal blood on contrast-enhanced images 1.
• The performance of multiphase acquisition, with a portal venous or a delayed phase, in addition to the angiographic phase, which can increase the sensitivity of CTA for detecting GIB 1.
• The avoidance of oral contrast, as it can render the examination nondiagnostic, and the use of oral water, which can dilute intraluminal hemorrhage 1.

Overall, CTA offers a valuable diagnostic tool for patients with right-sided abdominal pain and profuse GI bleeding, allowing for the simultaneous evaluation of appendicitis and active bleeding sources, and guiding further management and treatment.

From the Research

Diagnosis of Appendicitis with CTA Abdomen and Pelvis

• A Computed Tomography Angiography (CTA) of the abdomen and pelvis is primarily used to diagnose and manage acute gastrointestinal (GI) bleeding, as stated in the study 2.
• The study 2 highlights the role of CTA in providing diagnostic information to guide management of GI bleeding, but it does not specifically address the diagnosis of appendicitis.
• However, CTA can potentially identify appendicitis as it provides detailed images of the abdominal and pelvic structures, including the appendix.
• The presence of right-sided abdominal pain and profuse GI bleeding may indicate a condition such as a ruptured appendix, which could be visualized on a CTA scan.

Limitations of CTA in Diagnosing Appendicitis

• The studies 3, 4, and 5 focus on the management of upper gastrointestinal bleeding and do not provide direct evidence on the use of CTA for diagnosing appendicitis.
• The study 6 provides guidelines for the management of upper gastrointestinal and ulcer bleeding but does not address the diagnosis of appendicitis using CTA.
• While CTA can be useful in diagnosing various abdominal conditions, its primary use in the context of GI bleeding is to identify the source of bleeding, rather than to diagnose appendicitis specifically.

Potential for CTA to Identify Appendicitis

• Despite the lack of direct evidence, a CTA scan may still be able to identify appendicitis, especially if the appendix is ruptured or inflamed, as this would be visible on the scan.
• The study 2 suggests that CTA can provide diagnostic information to guide management, which could potentially include the diagnosis of appendicitis if the appendix is involved in the bleeding.
• However, a dedicated CT scan of the abdomen and pelvis without contrast (or with oral and IV contrast) is typically the imaging modality of choice for diagnosing appendicitis, rather than a CTA scan.