Herpes esophagitis is an infection of the esophagus, the muscular tube that carries food and liquid from the mouth to the stomach, caused by the herpes simplex virus (HSV). The infection destroys cells in the surface lining and produces small ulcers, which makes swallowing painful. It is also called herpes simplex esophagitis or HSV esophagitis.
Almost all cases are caused by herpes simplex virus type 1, the same virus responsible for cold sores around the mouth. This virus is very common: most adults have been infected at some point, usually in childhood, and after that first infection it stays permanently dormant in nerve cells. Carrying it is normal and is not a disease. Herpes esophagitis occurs when the dormant virus reactivates and travels to the esophagus, or occasionally during a first infection.
Herpes esophagitis is one of the two most common viral infections of the esophagus, alongside CMV esophagitis. It usually responds quickly to treatment, and in otherwise healthy people it often settles on its own. This article will help you understand the findings in your pathology report, what each term means, and why it matters for your care.
Herpes esophagitis develops when herpes simplex virus infects the squamous cells that form the surface lining of the esophagus. The virus multiplies inside these cells and destroys them, and as groups of cells die, the lining breaks down into small ulcers. Most cases represent reactivation of a virus that has been dormant since an earlier infection; a smaller number occur during a first infection, which is why the condition is sometimes seen in adolescents and young adults.
The infection is most common in people whose immune system is weakened, including:
It is worth being clear about a common misconception. Herpes esophagitis is not confined to people with serious immune problems. A meaningful number of cases occur in people who are otherwise entirely healthy, often after a period of significant physical or emotional stress, another infection, or a short course of steroids. If you have received this diagnosis and have no known immune condition, it does not necessarily mean one will be found. Your doctor will usually take a careful history and may check for an underlying cause, but in many healthy people no explanation is ever identified, and none is needed.
The most prominent symptom of herpes esophagitis is pain on swallowing, called odynophagia, which is often severe and characteristically comes on suddenly over a few days. Difficulty swallowing and chest pain behind the breastbone are also common, and the pain can be intense enough that people avoid eating and drinking.
Fever, sore throat, and a general feeling of being unwell frequently accompany the swallowing symptoms, particularly during a first infection. Cold sores on the lips or ulcers in the mouth are present in only a minority of people, so their absence does not argue against the diagnosis. Bleeding from an ulcer occurs occasionally and may appear as vomited blood or black stools.
The abrupt onset of severe painful swallowing in a previously well person is a fairly characteristic pattern, and it is one of the clues that prompts an endoscopy.
Herpes esophagitis is diagnosed by examining tissue taken from the esophagus during an upper endoscopy, in which a thin flexible tube with a camera is passed through the mouth. The typical appearance is many small, shallow, sharply outlined ulcers, most often in the lower esophagus, with normal-looking lining in between. The raised edges give these ulcers a distinctive appearance often described as volcano-like. In more advanced infection, the ulcers run together into larger raw areas, which can resemble other conditions.
Where the biopsies are taken from matters a great deal. Herpes simplex virus infects the squamous cells of the surface lining, and the infected cells are concentrated at the edge of each ulcer, where damaged lining meets healthy lining. Biopsies are therefore taken from the ulcer margins rather than from the crater. This is the opposite of CMV esophagitis, where the virus infects cells deep at the floor of the ulcer and biopsies must come from the base. Because sampling the wrong site can miss the infection, several samples are usually taken.
The tissue is examined by a pathologist, who looks for the changes described below. Samples are also checked for CMV and for fungal organisms, since more than one infection can be present at once in someone whose immune system is suppressed.
Under the microscope, herpes simplex virus produces a set of changes inside the infected squamous cells that are distinctive enough to make the diagnosis on their own. These are known collectively as viral cytopathic effects. Findings that may appear on your report include:
The first three findings are often grouped together as the three Ms of herpes infection: multinucleation, molding, and margination. When all three are present in squamous cells at an ulcer edge, the diagnosis is usually straightforward.
When the changes are subtle or only a few cells are affected, additional testing is used to confirm the diagnosis. Results may appear on your pathology report or on a separate laboratory report.
Blood tests for herpes antibodies are of limited value here. Because most adults carry the virus, a positive result simply confirms past exposure and does not show that the esophagus is infected.
Several infections can produce similar symptoms, and telling them apart matters because each is treated with a different medication.
The outlook for herpes esophagitis is good. In people with a normal immune system, the infection is usually self-limited, settling on its own over one to two weeks, and antiviral medication shortens that considerably, with most people improving within a few days of starting treatment. The ulcers heal without lasting damage, and recurrence in a healthy person is uncommon.
In people whose immune system is suppressed, the infection is more likely to be severe and prolonged, and treatment is more clearly necessary. It may also recur while immune suppression continues.
Complications are uncommon but can occur in either group, and include bleeding from an ulcer, narrowing of the esophagus from scarring, and rarely perforation or spread of the virus to other organs such as the liver or lungs. Prompt treatment reduces these risks, which is one reason antiviral medication is usually given even when the infection might have resolved on its own.
Herpes esophagitis is treated with antiviral medication. Acyclovir is the standard drug and is usually taken by mouth. When swallowing is too painful to take tablets, or when the infection is severe, or the immune system is significantly suppressed, it is given through a vein and switched to oral treatment once swallowing becomes comfortable. Valacyclovir and famciclovir are oral alternatives taken less frequently throughout the day.
Treatment usually runs for one to two weeks in a person with a normal immune system, and longer, commonly two to three weeks, when the immune system is suppressed or the infection is extensive. Most people notice a clear improvement within the first few days. If there is no response, the virus can be tested for resistance to acyclovir, and foscarnet is the usual alternative in that situation.
Because eating and drinking can be very painful in the first days, supportive care matters. Pain relief, attention to fluid intake, a soft or liquid diet, and sometimes an acid-suppressing medication to reduce further irritation of the ulcers are all commonly used. Occasionally fluids are given through a vein until swallowing improves.
Where the immune system is suppressed, the care team will consider whether immune-suppressing medication can be reduced or adjusted, balanced against the risk of rejection or of the underlying condition flaring. For someone with HIV, starting or resuming antiretroviral treatment is the most important long-term measure. For people with repeated episodes and ongoing immune suppression, preventive antiviral medication taken regularly is sometimes used.
A repeat endoscopy is not usually needed once symptoms have resolved. It may be arranged if symptoms persist, if the infection was unusually severe, or if there is another reason to look at the esophagus again.