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PubMed1983

A new type of low-lactose milk. Tolerance by lactose malabsorbers and evaluation of protein nutritional value.

By ultrafiltration of skim milk a new low-lactose milk powder was developed whose lactose content was reduced by 86%. The lactose was replaced by malto-dextrin. In contrast to lactose-hydrolyzed milk powder, no protein-destroying processes (Maillard reactions) could be demonstrated during production or after storage at standard conditions. Tolerance of the new low-lactose milk versus regular skim milk was tested in 35 well-nourished, adult Latin Americans with lactose malabsorption. The ingestion of 500 ml of the low-lactose milk gave rise to significantly (p less than 0.05) fewer symptoms than regular skim milk. After the intake of 250 ml there a tendency to fewer symptoms after the low-lactose milk, although the difference was not significant (0.05 less than p less than 0.1). The new milk may be of potential usefulness in the treatment of protein calorie malnutrition in the developing countries, where lactose malabsorption is highly prevalent.

Animals↗
PubMed2003

Lactose intolerance: analysis of underlying factors.

BACKGROUND: We studied the degree of lactose digestion and orocecal transit time (OCTT) as possible causes for the variability of symptoms of lactose intolerance (LI) in a sample of a population with genetically determined low lactase activity. METHODS: Lactose digestion index (LDI) was measured by the recently developed 13C-lactose/2H-glucose test. The OCTT was determined using the breath hydrogen test. Based on a 6-h symptom score (SSC) after a challenge dose of 25 g of lactose the subjects were divided into a tolerant group (T: n= 15; SSC = 0) and an intolerant group (IT: n= 28; SSC 1-40). The intolerant group was subdivided according to the severity of symptoms: group ITa (n = 17; mild symptoms without diarrhoea) and group ITb (n = 11; with diarrhoea). RESULTS: The LDI was lower in the intolerant group (0.34 +/- 0.14) (mean +/- SD) than in the tolerant group (0.47 +/- 0.14) (P = 0.008). The OCTT of group IT (60, 30-90 min) (median, quartiles) was significantly shorter than that of group T (105, 60-120 min) (P = 0.003) and was positively correlated with the LDI (P = 0.050). In groups ITa and ITb the OCTT (60, 30-90 min; 60, 26-83 min) and LDI (0.30 +/- 0.14; 0.39 +/- 0.14) were similar. CONCLUSIONS: Lactose digestion capacity, which is determined by small intestinal lactase activity as well as by OCTT, affects the occurrence of lactose intolerance. However, the major difference in intolerance symptoms is caused by differences in the colonic processing of maldigested lactose.

Adult↗
PubMed1975

Breath hydrogen as a diagnostic method for hypolactasia.

Breath hydrogen (H2), collected by end-expiratory sampling, was measured in twenty-five patients with abdominal symptoms or diarrhoea after ingesting 50 g. of lactose. This was compared with established tests of hypolactasia. Fifteen patients with a blood-glucose rise of more than 20 mg. per 100 ml. had less than 4 parts per million (p.p.m.) rise in breath H2 at 2 hours. In contrast, ten patients with blood-glucose rises of less than 20 mg. per 100 ml. had more than a 20 p.p.m. H2 rise (mean 85.8 p.p.m. plus or minus s.d. 44.3) at 2 hours. Similarly, two patients with normal jejunal lactase activity had no significant H2 production, whereas six patients with hypolactasia had more than a 20 p.p.m. rise in H2. Symptoms related to milk or lactose ingestion were found to be unreliable. End-expiratory sampling of breath H2 would seem to be a simple, non-invasive, and accurate method of diagnosing hypolactasia, which is also very acceptable to patients. This should make it a valuable tool both in diagnostic gastroenterology and in epidemiological surveys.

Biopsy↗
PubMed1987

Milk consumption, symptom response, and lactose digestion in milk intolerance.

The experience of adverse gastrointestinal symptoms (gas, abdominal pain, and diarrhea) after the oral ingestion of 360 mL whole milk was investigated in 25 adults who claimed to be milk intolerant. The level of customary milk consumption by all subjects was low compared with that of 13 control subjects who denied a history of milk intolerance. After drinking the milk, which was accompanied by a hydrogen breath test, most of the subjects experienced some of their accustomed intestinal discomfort and the degree of intolerance was similar for the nine (36%) who proved to be true lactose-maldigester subjects and the 16 (64%) who had flat hydrogen breath responses, ie, who were classified as lactose-digester subjects. There is a subpopulation of lactose-intolerant milk-rejector individuals that absorbs lactose efficiently and responds to other milk-related factor(s) with the same subjective symptoms and dietary conduct as do true lactose-maldigester individuals.

Adult↗
PubMed1983

Respiratory excretion of hydrogen and methane in Italian subjects after ingestion of lactose and milk.

Lactose malabsorption, by the breath hydrogen test, and lactose intolerance (presence of symptoms) were studied in twenty healthy Italian subjects after intake of 12.5, 25 and 50 g lactose, whole milk and low-lactose milk. A rise in respiratory concentration of hydrogen (greater than 20 ppm) (malabsorption) was found in fifteen subjects after 50 g lactose, in thirteen after 25 g and in seven after 12.5 g. Symptoms generally occurred in subjects presenting a rise in respiratory hydrogen excretion, but such a rise was often observed without symptoms. Thirteen subjects presented symptoms after 50 g lactose, but only three after 25 g and one after 12.5 g. Whole milk (500 ml) gave a lower incidence of lactose malabsorption than 25 g lactose (7/20 versus 13/20, P less than 0.05) and more subjects developed symptoms (7/20 versus 3/20, NS). Low-lactose milk produced no malabsorbers and one intolerant. Breath methane was detected constantly in seven subjects and in three on some of the days of observation. Respiratory methane excretion generally appeared to be unrelated to lactose ingestion.

Adult↗
PubMed1991

Milk-induced malabsorption in malnourished African patients.

Fifty malnourished rural African patients were randomly assigned to whole milk (50 g lactose/L), acidified milk (24 g lactose/L), or a commercial lactose-free diet (LFD) as a constant nasogastric infusion for 3 d, starting at 2 L/d and increasing to 3 L/d if tolerated. During the first 2 d mild symptoms of intolerance developed in 63% of patients on whole milk, 37% on acidified milk, and 54% on LFD whereas severe intolerance, necessitating withdrawal, was encountered in 22% receiving whole milk and none receiving LFD. Stool weights and fat excretion on day 3 were greater (P less than 0.02) in the remaining milk-fed patients whereas nitrogen balance remained strongly positive in all three groups. Eighty-seven percent of patients were methane producers, and high excretion rates were associated with better milk tolerance. The results suggest that although undiluted cow milk will not form a suitable tube feed for malnourished African patients, products such as acidified milk may prove cost effective.

Adult↗
PubMed1984

New principle for estimation of hydrogen in expired air.

A new device for estimation of hydrogen in expired air is described. The measuring principle consists of a semi-conductive detector with a high affinity for hydrogen. Experiments on reliability and reproducibility are satisfactory. A good correlation has been obtained with the results of gas chromatographic analysis of hydrogen in reference gases as well as in samples of expired air. Discrimination between lactose absorbers and lactose malabsorbers in 50 consecutive patients is the same when using both methods simultaneously. This so-called "Lactoscreen", supplied with separate collection systems for infants and for older children, provides a rapid estimation of breath hydrogen concentration. A built-in hydrogen generator produces hydrogen air mixtures of variable concentrations, thus obviating the need for external reference gases. The "Lactoscreen" appears to be reliable for routine screening for carbohydrate malabsorption in children and adults and is easy for medical assistants to handle.

Adult↗
PubMed1991

Late-onset hypolactasia in Hong Kong school children.

Three hundred and twenty Chinese school children aged between 6 and 19 years from six schools in Hong Kong were tested for their lactose digestion status. After an overnight fast, the children were challenged with cow's milk, 5 ml/kg bodyweight (i.e. lactose approximately 0.25 g/kg). Malabsorption was assessed by measuring hydrogen concentration from end-expiratory breath samples taken in duplicate before and at 90 and 180 minutes after the challenge. On average, 10% of the children showed an increase in breath hydrogen excretion within 3 h after the challenge, indicating malabsorption of lactose. None of the children complained of gastro-intestinal symptoms or showed any clinical sign of intolerance to the milk. The number of malabsorbers increased significantly (p less than 0.001) with age, starting at about 3% at the age of 8 and reaching about 27% at the age of 18 years. The sharpest rise occurred between 14 and 15 years. It is concluded that, despite the high prevalence of hypolactasia, Hong Kong Chinese children can consume normal amounts of milk without developing any untoward clinical symptom or sign.

Adolescent↗
PubMed1986

Two-hour lactose breath hydrogen test.

Current requirements for the lactose breath hydrogen test (LBHT) include serial expired air samplings and multiple hydrogen (H2) determinations. One hundred thirty-two consecutive LBHTs were evaluated to determine whether multiple samplings are indeed necessary for detection of lactose malabsorption. Expired air samples were collected at 0, 30, 60, 90, 120, 150, and 180 min following ingestion of lactose. Fifty-five LBHTs were positive for lactose malabsorption. All tests showed abnormally elevated breath H2 concentrations at 120 min. The mean value of the change in parts per million (delta ppm) of H2 at 120 min (51.1 +/- 4.7 SEM) was higher than at any other time point. If only the 120-min samples were examined without subtracting the initial concentrations, four of the 77 negative tests (5.2%) would have been falsely positive. Thus, the values of H2 at 0 and 120 min were sufficient to define lactose malabsorption in all cases. We conclude that just as a single blood sample now suffices for determining xylose malabsorption, so expired air sampling at only 0 and 120 min during the LBHT is a reliable method for detecting lactose malabsorption and diminishes the need for acquiring and analyzing multiple samples.

Adolescent↗
PubMed2005

Evaluation of a new DNA test compared with the lactose hydrogen breath test for the diagnosis of lactase non-persistence.

BACKGROUND AND AIMS: Recent publications have found that the CC genotype of the DNA variant -13910 T/C upstream of the LCT gene is associated with lactase non-persistence. We therefore compared the value of DNA testing for this variant (DNA test) with the lactose hydrogen breath test (H2 test), which is the clinical standard for the diagnosis of lactase non-persistence. PATIENTS AND METHODS: One hundred and twenty-three consecutive patients with suspected lactose malabsorption were tested for the presence of the -13910 T/C variant by polymerase chain reaction-restriction fragment length polymorphism analysis. These patients also underwent the H2 test after ingestion of 50 g lactose. RESULTS: Thirty-seven subjects had a CC genotype of the -13910 T>C polymorphism suggesting lactase non-persistence; 36 (97%) had also a positive H2 test. Eighty-six subjects had either a TC or a TT genotype suggestive of lactase persistence. Seventy-four (86%) of these tested negative on the H2 test, while 12 patients had a positive H2 test. In eight of these 12 patients duodenal biopsies showed no evidence of small bowel disease. One patient carrying a CC genotype had a negative H2 test. In this patient the rise in serum glucose after oral lactose was normal, furthermore H2 non-excretion was also excluded. CONCLUSIONS: An excellent correlation is observed between a CC genotype and a positive H2 test, whereas the correlation between a TC or TT genotype and a negative H2 test result is less strong. Analysis of the -13910 T/C variant can be considered a good test for predicting the presence of lactase non-persistence in a patient population with suspected lactose malabsorption.

Adolescent↗
PubMedDate not supplied

Test-retest reproducibility of hydrogen breath test for lactose maldigestion in preschool children.

The test-retest reproducibility of the H2 breath test within the same individual has not been rigorously evaluated in preschool children. In the present study, 10 children--5 of whom were diagnosed as lactose-digesters on their first testing, and 5 of whom were diagnosed as lactose-maldigesters at first screening--were retested under identical conditions of a second opportunity. In each case, the same diagnostic classification was provided, for a reproducibility of 100%. Regression of the area under the curve of the change in breath H2 concentration during the 3 h of the test had a Pearson's correlation coefficient of 0.59 (p = 0.05). The time-course of 3-h H2 breath tests in 43 children with lactose maldigestion revealed a peaking of the concentration of H2 most commonly 120 min following the oral dose of 240 ml whole milk. Seventy-seven percent of the children who eventually proved to be lactose maldigesters were so diagnosed by the end of the second hour of the breath test. Thus, even the abbreviated breath sampling schedule used in children is sensitive, and few maldigesters would go undetected because of a late rise in breath H2 concentration.

Animals↗