Lactose intolerance can occur if the baby has an illness like diarrhea, which causes a transient intolerance that may persist.
By Dr Saugata Acharya
Lactose intolerance is a disorder that affects people with a decreased ability to digest lactose, a sugar found in dairy products. Lactose intolerance can be of three types—congenital lactose intolerance, which occurs due to a deficiency of the enzyme lactase that metabolises the lactose we consume. So, congenitally, if a child or baby is deficient in lactase, it’s termed congenital lactose intolerance, which is a rare disease. Prevalent in Finland, where it’s found in one among 60,000 babies, it’s also referred to as the “Finnish type”. In primary lactose tolerance, babies are born with low lactase levels. Meanwhile, secondary lactose intolerance may occur if the baby has a certain illness, for instance, diarrhea which causes a transient lactose intolerance that may persist.
How to diagnose lactose intolerance
There are mainly three factors behind the diagnosis of lactose intolerance—abdominal pain, flatulence and diarrhea. If a newborn, fed on milk, suffers from recurring diarrhea and severe flatulence, or has colicky abdominal pain and is not gaining weight, then we can suspect food intolerance to be behind it. In some babies, it could be lactose intolerance and in others, it may be cow’s milk or protein intolerance.
On suspicion of lactose intolerance, certain tests are conducted. The Dimona test for lactose intolerance is a hydrogen breath test, which is not feasible for little children. Therefore, for babies, a stool test is conducted, and if it’s acidic (the PH of the stool less than 5.5, with a presence of reducing substance above 5 per cent), then it can be postulated that the baby has a possibility of lactose intolerance.
Treating lactose intolerance
The clinical findings need to be corroborated with the symptoms. For instance, not gaining weight, recurrent diarrhea, recurrent abdominal pain or vomiting are associated features of lactose intolerance. If the stool test is further suggestive of lactose intolerance, then lactose has to be eliminated from the diet. There are quite a few lactose-free formulas available in the market, which can be recommended by doctors. There can be some controversies on the need or continuation of breastfeeding since breast milk also contains lactose. Some authorities recommend that breastfeeding should be continued unless the child is highly symptomatic. Others recommend that it’s better to abstain from breast milk for a while to see if the symptoms improve. There may be a trial period where lactose is eliminated altogether from the feed and once the baby’s weight and symptoms are evaluated, suitable measures can be adopted.
If there is primary lactose intolerance, then the lactose-free diet needs to be continued for a prolonged period of time.
In case of secondary lactose intolerance, sometimes after an attack of diarrhea or dysentery, there can be a transient phase and milk-based feeds can be stopped during this span. Usually, children recover from secondary lactose intolerance and, after a while, they can start digesting lactose. However, if similar symptoms persist then the child has to undergo a medical retest and to decide if a lactose-free diet has to be continued for a longer period. There is no restriction with other diets barring lactose. After a lactose-free diet, it has been observed that such babies start gaining weight and symptoms improve to a large extent.
It’s important to know that lactose intolerance in a baby can occur anytime and not just during the weaning period. If a child has primary and congenital lactose intolerance, then he will be symptomatic from birth itself. For a child with symptoms of recurrent pain, diarrhea, flatulence or colic, the stool needs to be tested, which can be at six months, one year or anytime after an attack of diarrhea to detect evidence of lactose intolerance. If a child has been weaned, lactose can be eliminated easily as by then, solid diet has been usually introduced. If the child is diagnosed with lactose intolerance when he is predominantly milk fed, then a lactose-free formula needs to be introduced.
(The writer is a pediatric surgeon at Dept. of Paediatrics, CK Birla Hospitals–CMRI.)