Usai-Satta Paolo, Scarpa Mariella, Oppia Francesco, Cabras Francesco
Paolo Usai-Satta, Mariella Scarpa, Francesco Oppia, Francesco Cabras, Gastroenterology Unit, Brotzu Hospital, 09100 Cagliari, Italy.
World J Gastrointest Pharmacol Ther. 2012 Jun 6;3(3):29-33. doi: 10.4292/wjgpt.v3.i3.29.
Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an autosomal recessive condition resulting from the physiological decline of lactase activity. Different methods have been used to diagnose LM. Lactose breath test represents the most reliable technique. A recent consensus conference has proposed the more physiological dosage of 25 g of lactose and a standardized procedure for breath testing. Recently a new genetic test, based on C/T13910 polymorphism, has been proposed for the diagnosis of adult-type hypolactasia, complementing the role of breath testing. LM represents a well-known cause of abdominal symptoms although only some lactose malabsorbers are also intolerants. Diagnosing lactose intolerance is not straightforward. Many non-malabsorber subjects diagnose themselves as being lactose intolerant. Blind lactose challenge studies should be recommended to obtain objective results. Besides several studies indicate that subjects with lactose intolerance can ingest up to 15 g of lactose with no or minor symptoms. Therefore a therapeutic strategy consists of a lactose restricted diet avoiding the nutritional disadvantages of reduced calcium and vitamin intake.Various pharmacological options are also available. Unfortunately there is insufficient evidence that these therapies are effective. Further double-blind studies are needed to demonstrate treatment effectiveness in lactose intolerance.
乳糖吸收不良（LM）是由于乳糖酶缺乏导致乳糖水解不完全，其可能作为原发性疾病出现，也可能继发于其他肠道疾病。原发性成人型低乳糖酶症是一种常染色体隐性疾病，由乳糖酶活性的生理性下降引起。已采用不同方法诊断LM。乳糖呼气试验是最可靠的技术。最近的一次共识会议提出了25克乳糖这一更符合生理剂量以及呼气试验的标准化程序。最近，一种基于C/T13910多态性的新型基因检测方法被用于诊断成人型低乳糖酶症，补充了呼气试验的作用。尽管只有部分乳糖吸收不良者也不耐受乳糖，但LM是腹部症状的一个常见原因。诊断乳糖不耐受并非易事。许多非吸收不良者自认为乳糖不耐受。应推荐进行盲法乳糖激发试验以获得客观结果。此外，多项研究表明，乳糖不耐受者可摄入高达15克乳糖而无或仅有轻微症状。因此，治疗策略包括限制乳糖饮食，避免因钙和维生素摄入量减少带来的营养劣势。也有多种药物选择。遗憾的是，没有足够证据表明这些疗法有效。需要进一步的双盲研究来证明对乳糖不耐受的治疗效果。
