Cytomegalovirus esophagitis is one of the many types of infections caused by the cytomegalovirus and is primarily seen in immunocompromised individuals. Odynophagia, pain in the epigastric region, swallowing difficulties, vomiting, and nausea are some of the most important symptoms. A detailed clinical workup, microbiological studies, and upper endoscopy are vital components of the diagnostic workup.
Cytomegalovirus (CMV) is described as a causative agent of numerous end-organ infections in clinical practice  , and is mainly identified in immunocompromised hosts, such as those suffering from human immunodeficiency virus (HIV) infection, organ transplant recipients, dialysis patients, or other disorders that induce a severe immunosuppression (use of corticosteroids, congenital immunodeficiencies, etc.)   . However, a growing number of studies report CMV infection in the immunocompetent, both in children and adults   . Cytomegalovirus esophagitis, after CMV colitis, is the second most common site of gastrointestinal tract infection by this viral pathogen , and the clinical presentation ranges from asymptomatic with mild upper-GI related complaints (typical for immunocompetent) to severely debilitating  . Symptomatic patients present with odynophagia and dysphagia (swallowing of solid foods is particularly unpleasant and painful, whereas liquids are better tolerated), as well as pain in the epigastric, substernal or pharyngeal region     . Pain may be accompanied by a burning sensation and is often pronounced by ingestion of acidic beverages . Difficulties with swallowing might reach up to a point where patients suffer from weight loss and dehydration, which can be further aggravated by nausea and vomiting, two frequent complaints in cytomegalovirus esophagitis  . Fever is also reported in a minority of patients .
The differential diagnosis of symptoms related to the upper GI tract is broad. For this reason, physicians should obtain a proper patient history that will identify underlying immunosuppressive disorders that could point toward CMV esophagitis. After a detailed physical examination, the two most important parts of the workup are microbiological testing and imaging studies of the esophagus. Various methods have been described in the literature as a means of detecting CMV as the causative agent, including viral cultures, immunohistochemical staining, and serology, but the emergence of molecular methods, such as polymerase chain reaction (PCR) and reverse-transcriptase PCR (RT-PCR), has greatly improved the overall success of microbiological diagnosis   . To obtain a viable sample for testing, however, it is necessary to perform an upper endoscopy that allows a biopsy with subsequent histopathological examination, which is also useful in confirming CMV as the culprit . This procedure is equally important for solidifying CMV as the cause of esophagitis, as it allows a direct view of the esophageal lining. Although lesions may not be visible in all patients, erythema, exudation, erosions, and edema are common findings . A more concrete diagnosis of CMV esophagitis can be made in the presence of large solitary or multiple ulcers (often referred to as "punched-out" lesions) in the distal or middle part of the esophagus, considered as hallmarks of this infection    .