Lactose intolerance: clinical and genetic diagnosis

Abstract

Introduction: Lactose intolerance is a syndrome resulting from maldigestion of the disaccharide lactose due to lactase enzyme deficiency causing symptoms mainly gastrointestinal. It involves 4 main causes: congenital lactase deficiency; developmental lactase deficiency; primary lactose intolerance; and secondary lactase deficiency.

Objective: Review of the clinical presentation of lactose intolerance and the main methods available for its clinical diagnosis.

Methods: Literature review in the PubMed database, using the keywords “lactose intolerance” and “genetic test” and using the Boolean data type and. Only articles in English and published between the years 2017 and 2022 were included, totalizing 8 articles.

Results: The diagnosis of lactose intolerance is related to its type and uses the main diagnostic tests: oral lactose tolerance, genetic, expired hydrogen.

Conclusion: Regarding diagnostic methods, the expired hydrogen test is the one of choice, as it is not invasive, is easy to perform and has low cost. However, it does not dispense association with other diagnostic techniques. Genetic testing is also very usefull and its advantage is that there is no need to use the oral lactose tolerance test.