Milk Intolerance: Lactose Intolerance and Cow's Milk Protein Allergy

Lactose Intolerance versus Cow's Milk Allergy in Infants: A Clinical Dilemma

Due to its very early introduction, cow's milk is one of the first foods that can cause adverse reactions in human beings. Lactose intolerance (LI) and cow's milk allergy (CMA) are the most common adverse reactions to cow's milk. While LI is due to insufficient small intestinal lactase activity and/or a large quantity of ingested lactose, CMA is an aberrant immune reaction to cow's milk proteins, particularly casein or β-lactoglobulin. However, the clinical manifestations of LI and CMA, particularly their gastrointestinal signs and symptoms, are very similar, which might lead to misdiagnosis or delayed diagnosis as well as nutritional risks due to inappropriate dietary interventions or unnecessary dietary restriction. Formula-fed infants with LI should be treated with formula with reduced or no lactose, while those with CMA should be treated with formula containing extensive hydrolyzed cow's milk protein or amino acids. This review is therefore written to assist clinicians to better understand the pathophysiologies of LI and CMA as well as to recognize the similarities and differences between clinical manifestations of LI and CMA.

A novel approach for lactose determination in cow's milk exploiting smartphone-based digital-image photometry

Lactose, the main carbohydrate in cow's milk, may cause health problems for consumers with intolerance. Lactose determination in milk is hindered by the matrix complexity and lack of chromophore groups. Chromatography, volumetric, and spectrophotometric approaches involving chemical derivatization are time-consuming and require laborious sample preparation, which is incompatible with the high analytical demand. In this context, a novel approach is presented for lactose determination in milk exploiting smartphone-based digital-image photometry. It was based on a modification of the Benedict's method, involving formation of the violet Cu(I)/2,2'-biquinoline-4,4'-dicarboxylate (BCA) complex instead of the copper(I) oxide precipitate, aiming at improvement of sensitivity and precision. Sample pretreatment and analyte derivatization were performed in Eppendorf tubes with minimal reagent amounts and a smartphone camera was used for image acquisition under controlled conditions. Measurements were based on the RGB color system, taking channel G as the analytical response because of the complementarity with the color of the complex. Under the optimized conditions, the proposed procedure yielded a linear response up to 20 mg L-1 (r = 0.999), with a limit of detection of 1.5 mg L-1, which is compatible with determination of lactose in milk and dairy products categorized with low content of the sugar. The procedure takes less than 10 min, with a coefficient of variation of 3.0% (n = 12) and consumes as low as 160 μg Cu and 430 μg BCA per determination, thus being a more practical, fast, cost-effective, and environmental friendly analytical method.

The Neural Bases of Disgust for Cheese: An fMRI Study

The study of food aversion in humans by the induction of illness is ethically unthinkable, and it is difficult to propose a type of food that is disgusting for everybody. However, although cheese is considered edible by most people, it can also be perceived as particularly disgusting to some individuals. As such, the perception of cheese constitutes a good model to study the cerebral processes of food disgust and aversion. In this study, we show that a higher percentage of people are disgusted by cheese than by other types of food. Functional magnetic resonance imaging then reveals that the internal and external globus pallidus and the substantia nigra belonging to the basal ganglia are more activated in participants who dislike or diswant to eat cheese (Anti) than in other participants who like to eat cheese, as revealed following stimulation with cheese odors and pictures. We suggest that the aforementioned basal ganglia structures commonly involved in reward are also involved in the aversive motivated behaviors. Our results further show that the ventral pallidum, a core structure of the reward circuit, is deactivated in Anti subjects stimulated by cheese in the wanting task, highlighting the suppression of motivation-related activation in subjects disgusted by cheese.

Management of neonatal cow's milk allergy in high-risk neonates

BACKGROUND

We conducted a multicenter clinical survey to clarify the current attitudes to diagnosis or treatment of neonatal milk allergy (NMA) in institutions providing medical care for high-risk neonates in Japan.

METHODS

Questionnaires were distributed to 263 institutions that provide medical care for high-risk infants. Information was requested on the number of hospitalized neonates between January 2004 and December 2005, the number of neonates diagnosed with milk allergy, frequent clinical symptoms, and clinical tests performed routinely when NMA was suspected.

RESULTS

Responses were received from 145 institutions (55.1%). Of 69 796 hospitalized neonates, a diagnosis of cow's milk allergy was made in 0.21%. The incidence in infants with birthweight <1000 g was 0.35%. Gastrointestinal symptoms were identified as the most frequent symptoms that suggested NMA by 80% of institutions. A challenge test in each suspected case was performed in only 15% of institutions, even though it was considered to be the most significant test for diagnosis. Most institutions considered a specific immunoglobulin E test in cases of suspected NMA, but only one-third agreed on its diagnostic significance. A lymphocyte stimulation test was performed in only 5.5% of institutions.

CONCLUSIONS

This study is the first to show the incidence of NMA in institutions providing medical care for high-risk neonates in Japan. Current clinical tests may be insufficient for diagnosis of NMA in which non-immunoglobulin-E-mediated delayed allergic reactions are involved. Therefore, awareness of the clinical features of this disorder is required among neonatologists and allergists.

A re-appraisal of lactose intolerance

BACKGROUND

Lactose, beta-galactose-1,4-glucose, is hydrolysed by the enzyme lactase. Lactose intolerance occurs when lactase deficiency causes clinical symptoms.

AIMS

To provide an overview of lactose intolerance, including definition, aetiology and epidemiology, the clinical symptoms and diagnostic testing and management.

METHODS

A literature review was carried out to meet the aims of this paper. This resulted in the analysis of a database of patients tested for lactose intolerance to provide examples of the consequences of problems of terminology identified.

CONCLUSIONS

The terminology relating to lactose intolerance is confusing for clinicians and researchers. Clinicians need to ensure that these problematic terms do not cause diagnostic mistakes and inappropriate treatment. Researchers should be aware of inconsistent terminology in studies and resultant problems with the interpretation of results.