There are many kind of stress cause of experimental ulceration. Water-immersion restraint stress is a famous one of them. In rats, water-immersion restraint stress is a model of experimental ulceration. This is a well-known method involving immersion of limbs in water for a long time to produce the stress response, i.e., ulceration. Stress ulcers are produced spotted or linear ulcers that occur only in the gastric corpus. We encountered a case in which multiple hemorrhagic gastric ulcers formed in the stomach in a setting similar to water-immersion restraint stress.

The subject was a 54-year-old man with a chief complaint of weakness of the entire body and a history of gastric ulcers. On the night of August 29, mistaken as a suspicious person, he was chased by police officers, and he slipped and fell into a river. He returned to the river bank after a while, but both ends of the bridge were perpendicular below the bridge (Figure 1), and he could not reach land from there. He had no means of communication and stayed under the bridge. As the embankment had no horizontal surface but only an inclined surface and the horizontal blocks were soaking in water, it was impossible to keep dry. He coped with hunger and thirst by consuming the water of the river. On September 15, he was discovered by a person fishing at the opposite bank and was transported by ambulance. His physique and nutrition were moderate and his clothes were wet. He was conscious but weak. His blood pressure was 138/68 mmHg, pulse rate 78 beats/min, and rectal temperature 33.4˚C. There was no anemia, jaundice, spontaneous pain, or tenderness.

The results of blood tests at the first visit are shown in Table 1. Because of renal impairment and hyperkalemia, hemodialysis was started at the outpatient clinic. Tarry stools were detected during dialysis, and thus, emergency upper gastrointestinal endoscopy was performed after dialysis. As shown in Figure 2, multiple hemorrhagic gastric ulcers were identified mainly in the gastric body. After endoscopic hemostasis with a heater probe, he was admitted to the hospital. The antibiotic drug administered was sulbactam/ampicillin (SBT/ABPC); however, 3 days later, lower abdominal pain developed. Abdominal computed tomography (CT) (Figure 3) revealed a thick intestinal wall extending from the ascending colon to the transverse colon. Colonoscopy revealed that there was a pseudo membrane extending from the ascending colon to the transverse colon (Figure 4). Pseudo membranous colitis was diagnosed. Vancomycin was orally administered and the symptoms were ameliorated. Seven days later, he started eating meals, and 12 days later, he was withdrawn from dialysis because of an increase in the urine volume. He followed a favorable course thereafter, and upper and lower gastrointestinal endoscopy showed improvement. Therefore, 25 days later, he was discharged from hospital. Examination performed during the course showed negative test results for Helicobacter pylori antibody. At the present time he is followed up in our hospital as outpatient.

There are a variety of possible causes for the development of ulcers. The most common cause is H. pylori infection [1] ; however, reported cases of acute ulcers show that there are various types of stress (cerebrovascular disorders, thermal burns, infection, etc.) causing ulcers. The following experimental methods have been invented: direct stimulation (using electrical currents or drugs) of the brain (hypothalamus) [2] ; restraint [3] [4] ; physical stimuli using light, sound, electricity, etc.; and circulatory changes such as blood removal and thermal burns. Of all others, prolonged immersion in water under restraint, also called water-immersion restraint stress, is a method by which many ulcers can be developed in a comparatively short time [5] [6] . In the earlier method of water-immersion restraint stress, limbs of rats were fixed to a plate and immersed in water; however, a disadvantage was the occurrence of necrosis. This led to the development of another method involving placement of rats in small wire netting and immersion of their limbs in water without fixation, thus preventing the disadvantage [7] . In ulceration by water-immersion restraint stress, mucosal damage begins to occur from the second hour, and fairly obvious stress ulceration occurs in 7 hours. Water temperatures of 25˚C or more reduce the incidence of ulcers, and water temperatures of 20˚C or less leads to death of the experimental animals; therefore, the recommended water temperature is around 23˚C. Stress ulcers are produced spotted or linear ulcers that occur only in the gastric corpus, and they are histologically “erosion,” which fails to penetrate the muscularis mucosa. This is common to ulcers induced by other methods. The reason why ulcers occur in the gastric corpus of the fundic gland region but not in the pyloric gland region is attributed to the difference in the structure of capillaries between the fundic gland and pyloric gland regions. That is to say, the capillaries in the fundic gland region are disposed densely and each of them is thin and long, while the capillaries in the pyloric gland region are distributed roughly and disposed in a dendritic pattern. If blood flow is impaired there, the blood flow in the thin and long capillaries will decrease instantaneously, resulting in a mucous membrane disorder [8] . The ulcers in our case were multiple shallow ulcers that occurred chiefly in the gastric corpus. The riverbank on which the patient stayed put after falling into the river would have been a setting similar to water-immersion restraint stress, and multiple stress ulcers would have formed in the stomach, resulting in bleeding. At that time, the temperature was 28˚C in the daytime and around 20˚C at night because of late-summer heat. The subject could have escaped from rain because he was under the bridge; however, he could not escape from the water of the river. Although there is no data regarding the river water temperature, the water temperature measured in the same period several years later was around 18˚C (Table 2). It is said that, in experiments to produce ulcers by water-immersion restraint stress, animals will die if the water temperature is less than 20˚C. However, in water-immersion restraint stress experiments, rats are always immersed in water as high as the level of the chest. In our case, as the water level is suspected to have been up to the lower limbs, water is assumed to have not conducted heat away from the patient’s body all the time, and that aided survival of the patient.

We encountered a case in which multiple hemorrhagic stress-related ulcers developed under conditions relatively

similar to water-immersion restraint stress. It has been assumed that the subject survived more than 2 weeks because of summer heat since he was not soaked in the river water throughout.

Authors declare no conflict of interests for this article.

YoshihiroInoue,YasuhisaFujino,MakotoOnodera,SatoshiKikuchi,MasayukiSato,HisahoSato,HironobuNoda,MasahiroKkojika,YasushiSuzuki,ShigeatsuEndo, (2015) A Case of Multiple Hemorrhagic Gastric Ulcers Developed via a Mechanism Similar to Water-Immersion Restraint Stress. Open Journal of Clinical Diagnostics,05,136-140. doi: 10.4236/ojcd.2015.54022