by Jason Wasserman MD PhD FRCPC
June 28, 2023
CMV esophagitis is caused by infection of the cells on the inside of the esophagus with cytomegalovirus (CMV).
People who have a weakened immune system are at risk for developing CMV esophagitis. A weakened immune system can be caused by medications such as those taken after a solid organ or bone marrow transplant, corticosteroids or immune modulators, and HIV infection. CMV esophagitis is rare in people with a normal immune system.
The most common symptoms of CMV esophagitis are difficulty swallowing or pain when swallowing foods or liquids.
The diagnosis of CMV esophagitis can be made after your doctor examines the inside of your esophagus with a camera called an endoscope. During the examination, small white abnormal areas of tissue called ulcers may be seen on the inside of the esophagus. A procedure called a biopsy may be performed to remove a small piece of tissue from the affected area. The tissue will be sent to a pathologist for examination under the microscope.
The cells that normally cover the inside of the esophagus are called squamous cells and they form a barrier called the epithelium. Below the epithelium is a thin layer of connective tissue called lamina propria. Within the lamina propria are blood vessels that are lined by endothelial cells. The lamina propria also contains fibroblasts which support the other cells. In CMV esophagitis, both the endothelial cells and the fibroblasts can be infected with the virus. When examined under the microscope, the infected cells have an abnormally large nucleus (the part of the cell that holds the genetic material) that often contain blue/purple dots called intranuclear inclusions. Inflammatory cells, including neutrophils, lymphocytes, and histiocytes, may also be seen around the infected cells.
Your pathologist may perform a test called immunohistochemistry (IHC) which allows them to see the virus inside infected cells. This confirms the diagnosis of CMV esophagitis.