One of the great advances in medicine in the 20th century was the introduction of oral rehydration therapy. Thanks to this simple, affordable therapy, mortality from acute diarrhoea has all but disappeared in middle and high income countries. It also has reduced mortality in low income countries but there is still much work to do. This work includes the World Health Organisation’s plan to end preventable child deaths from diarrhoea by 2025 (WHO 2013). While this is a first priority in the treatment of children with diarrhoea, another important step is to reduce the burden of disease.
Acute diarrhoea is commonly caused by infectious gastroenteritis. The most frequent cause remains rotavirus infections (although, thanks to the vaccine, it is also decreasing). And since some infections result in transient lactose intolerance it sounds logical to avoid lactose for a while.
Logical, yes. But is it practical?
Infants are usually the most affected by acute diarrhoea, and milk (either human or cow’s milk) is a main component of their diet. Is it possible to remove lactose from their diet? The answer is yes, but again, a lot of questions emerge. Do we temporarily suspend breastfeeding to avoid human milk lactose? Do we switch to a lactose-free formula? Do we dilute the formula to reduce lactose concentration?
And more important, is it worth it? How much does it help?
A Cochrane review (MacGillivray 2013) examined the effect of lactose avoidance in children under five years with acute diarrhoea. The review included 33 trials (2,973 children) and found that lactose free feedings reduced the duration of diarrhoea by 18 hours. It also reduced treatment failure, defined as the discontinuation of the intervention or withdrawal from the trial or change in nutritional management due to worsening diarrhoea or vomiting.
There are a few caveats, however, to this review. Most trials were conducted in the 1980’s and 1990’s, at a time when the rotavirus vaccine wasn’t available. Back then clinical trials did not follow strict reporting guidelines. Thus, the quality of the evidence ranges from moderate to very low. Also, none of the trials were conducted in low income countries. Most excluded predominantly breastfed infants or had no information about breastfeeding.
Diluted lactose-containing milk did not seem to reduce the duration of diarrhoea. And neither intervention had a significant effect on need for hospitalisation, duration of hospital stay, or stool volume.
So, what do we do?
Almost a day less of diarrhoea probably sounds good to any parent. But we can only apply the results to infants that are predominantly formula fed and live in middle or high income countries. The main focus of treatment should continue to be oral rehydration. Lactose avoidance, along with other supplementary therapies such as probiotics or zinc, may be considered in certain infants.
See the Evidence for Clinicians column published in the December 2014 issue of Paediatrics & Child Health commenting on the Cochrane review: http://bit.ly/1A7fZdS
- MacGillivray S, Fahey T, McGuire W. Lactose avoidance for young children with acute diarrhoea. Cochrane Database of Systematic Reviews 2013, Issue 10. Art. No.: CD005433. DOI: 10.1002/14651858.CD005433.pub2. See summary here.
- Lazzerini M, Ronfani L. Oral zinc for treating diarrhoea in children. Cochrane Database of Systematic Reviews 2013, Issue 1. Art. No.: CD005436. DOI: 10.1002/14651858.CD005436.pub4. See summary here.
- Allen SJ, Martinez EG, Gregorio GV, Dans LF. Probiotics for treating acute infectious diarrhoea. Cochrane Database of Systematic Reviews 2010, Issue 11. Art. No.: CD003048. DOI: 10.1002/14651858.CD003048.pub3. See summary here.
- Ending Preventable Child Deaths from Pneumonia and Diarrhoea by 2025: The integrated Global Action Plan for Pneuomnia and Diarrhoea (GAPPD). (2013). WHO report.
About Dr. Giordano Pérez-Gaxiola:
Dr. Giordano Pérez-Gaxiola is a paediatrician in Culiacán, México. He works in a public paediatric hospital and also has a private practice. He is currently one of the coordinators of the Mexican Branch of the Iberoamerican Cochrane Centre and is one of the Spanish editors of Testing Treatments interactive.