浅表性胃炎是指胃黏膜表层发生的炎症，其主要特征是胃壁红肿和水肿。浅表性胃炎的患者常常出现持续消瘦的情况，这与疾病本身以及相关的生理机制有关。

首先，浅表性胃炎导致了食欲减退。胃是食物消化的重要器官，但当胃黏膜受到炎症影响时，它的消化功能可能会受到一定程度的抑制。这会导致患者食欲减退、胃口不振，进而影响食物的摄入量和消化吸收。

Firstly, superficial gastritis leads to decreased appetite. The stomach is an important organ for food digestion, but when the gastric mucosa is inflamed, its digestive function may be inhibited to some extent. This can result in decreased appetite and a loss of interest in food, thereby affecting the intake and absorption of nutrients.

其次，胃炎引发了胃酸分泌的紊乱。正常情况下，胃酸是帮助消化食物的重要物质。然而，浅表性胃炎使得胃酸分泌受到干扰，可能导致胃酸的分泌过多或过少。胃酸分泌异常会影响胃内的酸碱平衡，并影响食物的消化和吸收。这种酸碱平衡失调可能导致患者出现腹胀、腹痛等不适症状，进而影响食欲和体重。

Secondly, gastritis disrupts the secretion of gastric acid. Under normal circumstances, gastric acid is an important substance for food digestion. However, superficial gastritis can interfere with the secretion of gastric acid, leading to either excessive or insufficient secretion. Abnormal gastric acid secretion affects the acid-base balance in the stomach and impairs digestion and absorption of food. This imbalance in acid-base ratio may cause symptoms such as bloating and abdominal pain, which further affects appetite and weight.

此外，浅表性胃炎还可能引发胃溃疡。胃溃疡是胃黏膜受损后形成的创面，其特点是剧烈的疼痛和消化道出血。患者可能会因为疼痛而不愿进食，从而导致食物摄入不足和体重下降。

Furthermore, superficial gastritis can also lead to gastric ulcers. Gastric ulcers are wounds that form on the gastric mucosa after it is damaged, characterized by severe pain and gastrointestinal bleeding. Patients may be reluctant to eat due to the pain, resulting in inadequate food intake and weight loss.

最后，慢性炎症状态对机体的代谢也会产生影响。浅表性胃炎是一种慢性炎症疾病，持续发炎可能导致机体消耗增加，促使身体分解脂肪和肌肉组织，从而导致消瘦。

Lastly, the chronic inflammatory state can also affect the body's metabolism. Superficial gastritis is a chronic inflammatory disease, and persistent inflammation can lead to increased energy consumption in the body, promoting the breakdown of fat and muscle tissue, resulting in weight loss.

总结起来，浅表性胃炎引起的消瘦可以归因于食欲减退、胃酸分泌紊乱、胃溃疡和慢性炎症状态对机体代谢的影响。这些因素共同作用，导致了患者的持续消瘦。因此，在治疗浅表性胃炎的过程中，除了抑制炎症和维护胃黏膜健康外，还应重视营养支持，以保证患者的摄入量和吸收能力。

In conclusion, weight loss caused by superficial gastritis can be attributed to decreased appetite, disrupted gastric acid secretion, gastric ulcers, and the impact of chronic inflammatory states on the body's metabolism. These factors work together to result in sustained weight loss in patients. Therefore, in the treatment of superficial gastritis, in addition to suppressing inflammation and maintaining gastric mucosal health, nutritional support should be emphasized to ensure adequate intake and absorption for the patients.

注：The information provided is for educational purposes only and should not be considered as medical advice. It is always important to consult with a healthcare professional for proper diagnosis and treatment.