White Esophageal Mucosa and Black Gastric Mucosa: Upper Gastrointestinal Injury Due to Hydrochloric Acid Ingestion

ingestion can cause severe injury to the esophagus and stomach. The severity and extent of esophageal and gastric damage resulting from caustic ingestion depend upon several factors. In the present report, we describe the case of a 55-year-old schizophrenic man who drank 400 mL of hydrochloric acid. Endoscopy indicated the presence of white esophageal mucosa and black gastric mucosa, which is evident in the images taken before and after ingestion (Fig. 1). Acid ingestion typically produces a superficial coagulation necrosis that results in thrombosis of underlying mucosal blood vessels and consolidation of connective tissue, thereby forming a protective eschar. 1 Because acid solutions cause pain upon contact with the oropharynx, the amount of acid in-gested tends to be limited. However, in the present case, the patient had schizophrenia, and despite experiencing pain, he drank 400 mL of hydrochloric acid. We believe that the excess hydrochloric acid injured the esophageal mucosa and subsequently turned the esophagus white, due to the development of mucosal edema, exudates, and superficial coagula-tion necrosis. Typically, when acid is ingested, it flows along the lesser curvature of the stomach towards the pylorus, and pylorospasm impairs emptying into the duodenum, producing stagnation and injury that is particularly prominent in the antrum. 2 However, in the present case, excess acid stagnated in the stomach, and as a result, we believe that the gastric mu-cosa was damaged up to the transmural layer, causing the black coloring of the mucosa. The severity and extent of esophageal and gastric damage resulting from caustic ingestion depend upon three major factors: corrosive properties of the ingested substance; duration of contact with the mucosa; and the amount, concentration , and physical form (solid or liquid) of the agent. 3,4 Most ingestions occur in children, whereas the other cases involve psychotic, suicidal, or alcoholic subjects. 5 The present case was a subject who was both psychotic and suicidal. Caustic ingestion is usually accidental in children under the age of 5 years and intentional in adults and adolescents. Highly concentrated acids (hydrochloric, sulfuric, and phosphoric acid) present in toilet bowl or swimming pool cleaners, anti-rust compounds, or in battery fluid are less frequently ingest-ed than alkalis. 4 When acid remains on the esophagus, burns can occur within 4 hours and perforation can occur within 6 hours; in such cases, urgent endoscopy is indicated. In the present case, we performed esophagogastroduodenoscopy (EGD) within 4 hours of ingestion. Alkali …