Dieulafoy lesions are often asymptomatic unless the mucosa overlying the vessel erodes, resulting in bleeding. The signs and symptoms are related to blood loss either due to intermittent or massive gastrointestinal hemorrhage. Melena is the most common presentation followed by hematemesis, hematochezia, iron deficiency anemia (IDA), hemoptysis, or hemodynamic instability. In rare circumstances, Dieulafoy lesion of the gall bladder may present with upper abdominal pain in the absence of overt bleeding.[11] 

Direct endoscopic visualization of the Dieulafoy lesion is the gold standard method for diagnosis. Most patients are diagnosed after a single endoscopy; however, poor visualization of the GIT due to food particles or blood may require multiple endoscopies. The endoscopic visual diagnostic criteria that are necessary for a diagnosis of Dieulafoy lesion is as following:

• Normal mucosa around the small defected mucosal lesions which has active pulsatile bleeding smaller than 3 mm
• The visualization of a protruding vessel from a slight defect or normal mucosa
• The observation of a fresh clot attached to a defect of normal mucosa[12]

If lesions are not detected by endoscopy, angiography, and capsule endoscopy can be used to confirm the diagnosis. On angiogram, there is extravasation of contrast into the GIT from the eroded artery. The presence of tortuous vessels in the arterial phase with no early venous return is also indicative of Dieulafoy lesions. The source of the bleeding is visualizable using technetium-99m red blood cell scanning or computerized tomography (CT) angiography.[13] 

The first-line treatment modality for Dieulafoy lesion is endoscopy.[14] In the past, surgical treatment with gastrostomy or gastrectomy was performed; however, it has been primarily replaced by endoscopy since 1986. The three commonly performed endoscopic treatment procedures include:

• thermal, heat probe or argon plasma coagulation
• regional injection-epinephrine (EPI) or norepinephrine(NOR) injection and sclerotherapy
• Mechanical banding and hemoclips[6][15]

Mechanical hemostasis comprising of banding and hemoclips is the safest and most effective treatment.[16] A study by Alis et al. revealed that endoscopic band ligation (EBL) was associated with a lower risk of recurrent bleeding and shorter hospital stay compared with sclerotherapy.[15] Hemoclipping has proven effective in the treatment of Dieulafoy lesions with a success rate of 95%.[17] Combination therapy has better outcomes when compared with monotherapy for Dieulafoy lesions. During endoscopic treatment, the bleeding site is often tattooed with India ink for ease of future identification in the event of a recurrent bleed.[18] If endoscopic treatment fails, surgical treatment is performed, which includes wide wedge resection or partial /wedge gastrectomy.[19] 

Dieulafoy lesion has a vast number of differential diagnoses based on the patients’ age, presence of comorbidities, and overall health. Angiodysplasia is an important differential due to similar presenting symptoms. It can be differentiated on angiography, by the presence of arteriovenous shunting and vascular ectasia, and by histological examination of the lesion which reveals the presence of abnormal submucosal vessels. Other similar conditions should be differentiated from Dieulafoy lesion based on presenting signs and symptoms, endoscopy, and angiography. These include diverticulosis, telangiectasias, vascular neoplasms, mucosal spider nevi, and connective tissue disorders.

The mortality and morbidity of Dieulafoy lesions have significantly reduced to 8.6% since the development of endoscopy.[8] Hemostasis is successfully achievable in 80 to 85% of the cases treated with endoscopy.

Due to the subtle nature of the disease, it is often missed as a diagnosis initially and may result in delayed treatment resulting in adverse complications. The most common complication is massive spontaneous gastrointestinal hemorrhage that may be fatal if left untreated. Intermittent blood loss may lead to iron deficiency anemia (IDA) and, in severe cases, hemodynamic instability. In some cases, it may lead to the worsening of pre-existing co-morbidities.

Patients need to minimize the risk factors for Dieulafoy lesion by avoiding the use of nonsteroidal anti-inflammatory drugs (NSAIDs) and alcohol. Regular follow up with a gastroenterologist is necessary to monitor the condition and prevent a recurrence.

Most cases of Dieulafoy lesion go undiagnosed due to lack of awareness, acute onset of signs and symptoms, intermittent bleeding pattern, and difficulty in visualization on endoscopy. On endoscopy, Dieulafoy lesion may be difficult to diagnose due to its small size or the presence of normal-appearing surrounding mucosa.[9] 

Excessive blood in the GIT may also prevent visualization and further delay diagnosis. For these reasons, physicians and endoscopists should consider this condition as a differential diagnosis for intermittent or massive GIT bleeding. Radiologists should also be aware of the subtle nature of this condition that may be missed in a patient with gastrointestinal bleeding. Once diagnosed, endoscopy should be the preferred treatment since it has replaced invasive surgery due to better health care outcomes. During the evaluation of the lesion, it is essential to determine the focal point of the bleeding for the management of future episodes.