Esophagitis overview

# Overview
The esophagus is a part of the gastrointestinal tract which is responsible of moving the food from the mouth to the rectum. Esophagitis is a general term for any inflammation, irritation, or swelling of the esophagus.  The inflammation can be due to a variety of causes such as gastroesophageal reflux disease, viruses, or chemical injuries. Basing on the etiology and severity of disease, esophagitis into 4 types ( eosinophilic esophagitis, infectious esophagitis, pill induced esophagitis, and reflux esophagitis) and 4 grades (grade 1, grade 2, grade 3, and grade4) respectively. When ever esophagus gets irritated whether due to acid reflux or any other disease process inflammation sets in. If left untreated, chronic inflammation can lead to metaplasia of lower esophagus and ultimately leading to carcinoma of esopahgus. The most common symptoms of the esophagitis include halitosis, epigastric chest pain, often radiating to the back, dysphagia, odynophagia, hoarseness, oral ulcers and must be differentiated from other diseases such as  peptic ulcer disease, acute coronary syndrome, angina pectoris, cholecystitis, biliary colic, pulmonary embolism and esophageal perforation. Prognosis of esophagitis is generally good with appropriate treatment. Diagnosis of esophagitis is mostly clinical. The mainstay of therapy for reflux esophagitis is acid suppression therapy. Patients with infectious esophagitis are treated with antimicrobial therapy, whereas patients with eosinophilic esophagitis are treated with corticosteroids.

# Historical Perspective
GERD is believed to be first described and treated by the ancient Egyptians according to the papyrus which was discovered by Edwin Smith at Thebes. The esophagus itself was named by the ancient Greeks. Friedenwald, and Feldman described the symptoms of GERD in 1925. Robbins and Jankelson used the radiological procedures to observe GERD in 1926. In 1981, Picus and Frank reported a case of a 16-year-old boy with progressive dysphagia for 1.5 years, endoscopic findings were suggestive of multiple 1-mm nodular filling defects in the esophagus in an area of stricture with dilatation above. The radiology showed a luminal narrowing, wall rigidity, and high circulating eosinophil count assumed to be a variant of eosinophilic gastroenteritis.

# Classification
Esophagitis may be classified according to the Los Angeles Classification into 4 grades.

# Pathophysiology
The esophagus is a part of the gastrointestinal tract which is responsible of moving the food from the mouth to the rectum. Esophagitis is defined as inflammation of mucosal layer of esophagus. Based on the etiology of inflammation esophagitis can be classified into reflux esophagitis and eosinophilic esophagitis. Any condition that lead to the reflux of the gastric acidic contents into the esophagus results in reflux esophagitis. Eosinophilic esophagitis is an immunoallergic disorder resulting from the interaction between genetics and environmental triggers such as repeated exposure to food and aeroallergens. TH2 inflammatory cell response play a major role in the production of eosinophils. Activated TH2 response leads to the recruitment and activation of eosinophils and mast cells. Characteristic gross pathology findings of esophagitis include fixed esophageal ring, white exudates, longitudinal furrows/ fibrosis, mucosal pallor, Diffuse esophageal narrowing. Characteristic microscopic findings  of esophagitis include edema and basal hyperplasia (non-specific inflammatory changes), lymphocytic infiltration, neutrophilic infiltration, eosinophilic infiltration, goblet cell intestinal metaplasia or Barrett's esophagus and elongation of the papillae.

# Causes
Common causes of esophagitis include gastroesophageal reflux disease, Barrett's esophagus, caustic burns, and chemical injury by either alkaline or acid solutions.  Among immuncompromised patients, the most common causes of esophagitis are Candidiasis, Cytomegalovirus, and Herpes simplex virus

# Differentiating Esophagitis overview from Other Diseases
Esophagitis must be differentiated from gastritis, peptic ulcer disease, gastroesophageal reflux disease, acute coronary syndrome, angina pectoris, cholecystitis, biliary colic, pulmonary embolism and esophageal perforation, rupture and tears.

# Epidemiology and Demographics
In the USA and Europe, the prevalence of GERD ranges from low of 10,000 per 100,000 persons to high of 20,000 per 100,000 people. In Asia, the prevalence of GERD is 5,000 per 100,000 people. The prevalence of EoE is approximately 50-100 per 100,000 individuals worldwide. In the USA, the incidence of GERD is 5,400 per 100,000 persons. In Europe, the incidence of GERD is 840 per 100,000 persons. The incidence of EoE is approximately 10 per 100,000 individuals worldwide. The prevalence of GERD increases with age. GERD affects all age groups but it affects more the people older than 40 years. Patients of all age groups may develop EoE. Men and women are affected equally by GERD. Males are more commonly affected by EoE than females. There is no racial predilection for GERD. EoE usually affects individuals of the white race.

# Risk Factors
Common risk factors in the development of esophagitis are immunosuppression, alcohol use, smoking, excessive vomiting, certain medications, and surgery or radiation to the chest.

# Screening
There is insufficient evidence to recommend routine screening for Esophagitis.

# Natural History, Complications, and Prognosis
If left untreated, 20% of patients with esophagitis may progress to develop esophageal stricture due to excessive acid in the lower esophagus. Common complications of esophagitis include esophageal ulcer, and esophageal adenocarcinoma. Prognosis of esophagitis is generally good with appropriate treatment.

# Diagnosis

## Diagnostic Criteria

## History and Symptoms
The most common symptoms of the esophagitis include halitosis, epigastric chest pain, often radiating to the back, dysphagia, odynophagia, hoarseness, oral ulcers.

## Physical Examination
The physical examination usually is not helpful in confirming the diagnosis of uncomplicated esophagitis. However, the examination may reveal other potential sources of chest or abdominal pain.

## Laboratory Findings
A complete blood count (CBC) is performed in patients with neutropenia or who are immunosuppressed. A CD4 count and HIV test are performed in patients with risk factors for HIV. A collagen workup (eg, antinuclear antibody , anti-dsDNA) may be performed based on the underlying disease.

## Electrocardiogram Findings
There are no specific electrocardiogram findings associated with esophagitis.

## X-ray
Barium studies cannot diagnose esophagitis but are helpful in identifying any underlying anatomical abnormalities such as strictures or rings.

## Echocardiogram/ultrasound findings
There are no echocardiography/ultrasound findings associated with esophagitis.

## CT
There are no CT scan findings associated with esophagitis. However, a CT scan may be helpful in the diagnosis of complications of esophagitis such as tears, perforation, strictures, etc.

## MRI
There are no MRI findings associated with esophagitis. however, MRI may be helpful in the diagnosis of complications of esophagitis such as tears, perforation, strictures, etc.

## Imaging Findings
There are no other imaging findings associated with esophagitis.

## Other Diagnostic Studies
The endoscope has been before one of the diagnostic tools for esophagitis. However, endoscopy is not recommended now for the diagnosis of esophagitis with the typical symptoms, however, it is used in screening for the esophagitis complications such as esophageal strictures, and barrett's esophagus.

# Treatment

## Medical Therapy
The mainstay of therapy for reflux esophagitis is acid suppression therapy. Patients with infectious esophagitis are treated with antimicrobial therapy, whereas patients with eosinophilic esophagitis are treated with corticosteroids. Supportive therapy for esophagitis includes proton pump inhibitors, topical pain medications (gargled or swallowed), smoking and alcohol cessation, and endoscopy to remove any lodged pill fragments.

## Surgery
Surgical intervention is not recommended for the management of esophagitis. However, esophageal dilation can be employed in cases of severe dysphagianot responding to medial therapy.

## Primary prevention
Effective primary preventive measures for esophagitis include weight loss, having head elevated while sleeping, and avoidance of certain foods that can trigger inflammation of esophagus.

## Secondary prevention
There are no established measures for the secondary prevention of esophagitis.