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PubMed1999

Ineffectiveness of breath methane excretion as a diagnostic test for lactose malabsorption.

BACKGROUND: In clinical and field conditions, breath gas analysis has been widely used in evaluating carbohydrate digestion. A field study was performed to determine the prevalence of lactose malabsorption in Myanmar children and to evaluate the possibility of using breath methane excretion to indicate lactose malabsorption in a field situation. METHODS: The study population consisted of 118 children aged 1 to 12 years. A hydrogen breath test after a lactose meal (2 g/kg, maximum 50 g) was used as a standard test. RESULTS: Lactose malabsorption was detected in 16.7% of children aged 1 to 2.9 years, with the prevalence increasing with age from 40.5% of those aged 3 to 5.9 years to 88.5% of those aged 6 to 8.9 years and reaching 91.7% in those aged 9 to 11.9 years. Lactose malabsorption was more prevalent when children were weaned before 4 months of age (87.2 vs. 41.1%; p < 0.01). Compared with lactose-tolerant children, those with lactose malabsorption had significantly higher concentrations of breath hydrogen excretion 60 minutes after the lactose test meal. Breath methane excretion was also significantly higher in samples at 120 minutes in children with lactose malabsorption. Breath methane excretion of greater than or equal to 2 parts per million at 180 minutes as a diagnostic test for lactose malabsorption had a sensitivity of 61.5% and a specificity of 84.6%. CONCLUSION: The breath methane test for lactose malabsorption has a lower sensitivity and specificity than the breath hydrogen test and therefore does not replace the lactose breath hydrogen test.

Breath Tests↗
PubMed1999

Occupational asthma induced by cephalosporins.

A 20-yr-old pharmaceutical worker who developed attacks of shortness of breath and wheezing 9 months after beginning work on a process in which cefadroxil powder was bottled or encapsulated will be described. Skin test with cefaxodril was negative. Baseline spirometry and methacholine inhalation test were normal. A controlled bronchial challenge test was carried out in a closed-circuit system with assessment of respirable dust concentration. Exposure to cefadroxil powder at a mean concentration of 10 mg x m(-3) for 10 min elicited an isolated immediate asthmatic response, but no response was observed to control challenge with lactose. Single-blind oral challenge test with amoxicillin up to 500 mg was well tolerated, whereas the oral challenge with cephalexin (25 mg) elicited an immediate asthmatic response. This patient had developed occupational asthma caused by inhalation of cefadroxil as confirmed by specific inhalation test. Since she tolerated oral amoxicillin, a synthetic penicillin with the side-chain identical to that of cefadroxil, it seems that she may be sensitized to the dihydrothiazine ring of cephalosporins.

Adult↗
PubMed1998

Lactose intolerance and self-reported milk intolerance: relationship with lactose maldigestion and nutrient intake. Lactase Deficiency Study Group.

BACKGROUND: The relationship between lactose-maldigestion, self-reported milk intolerance and gastrointestinal symptoms has not been clearly defined. OBJECTIVES: To evaluate: a) the prevalence of lactose maldigestion and lactose intolerance in a sample of the general population taken from a rural center; b) the frequency of self-reported milk-intolerance and its correlation with lactose-maldigestion; c) the influence of lactose maldigestion, lactose intolerance and self-reported milk intolerance on dietary habits and consumption of total calories, protein, and calcium. SUBJECTS: We studied a randomized sample of the general population in a small center in Sicily. 323 subjects (150 males, 173 females), age range 5 to 85 years (median 44) were included and underwent H2-breath test after 25 g lactose load. The preliminary dietary investigation spanned 7 consecutive days using a printed dietary form and was under the daily control of a team of dietitians. METHODS: The dietary investigation was completed in the first part of the study and the results were analyzed for nutrient composition by a computerized database. The subjects were then divided into self-reported milk-intolerants and self-reported milk-tolerants and they underwent H2 breath testing; subjects with H2 concentration >20 ppm over the baseline concentration were considered maldigesters and those with one or more symptoms were classified as intolerants. RESULTS: 104/323 subjects (32.2%) were lactose maldigesters but tolerants, while 13/323 (4%) were lactose maldigesters and intolerants. In each age-class group (pediatric, adult, and elderly subjects) only the lactose maldigester and intolerant subjects showed differences in nutrient intake with a significantly lower daily consumption of milk and a lower calcium intake. 49/323 subjects were self-reported milk-intolerants; of these, 26 (53%) were lactose maldigesters but tolerants, 18 (37%) were lactose digesters and tolerants and only 5 (10%) were lactose maldigesters and intolerants. In the whole group of self-reported milk-intolerants, dietary milk consumption was significantly reduced and calcium intake was lower than in all the other subjects studied (320 mg/day vs. 585 mg/day, p<0.05). CONCLUSIONS: In studies of the general population, the frequency of lactose intolerance is much lower than that of lactose maldigestion. Gastrointestinal symptoms after lactose load in self-reported milk-intolerants are found in only a very low number of these subjects. Furthermore, in these subjects we observed an unnecessary reduction in milk consumption and an insufficient dietary calcium intake.

Adolescent↗
PubMedDate not supplied

Lactose intolerance in protein-energy malnutrition: a clinical case study and family study using a hydrogen (H2) breath-analysis test for carbohydrate malabsorption.

A non-invasive, interval sampling hydrogen (H2) breath-analysis test for carbohydrate malabsorption was used in a 3 year-old Guatemalan child with severe protein-energy malnutrition (kwashiorkor) and in this relatives: mother half-sister and step-father to examine genetic and nutritional factors in lactose intolerance in young children. Clinical lactose intolerance was present in the patient on admission, and lactose malabsorption, even of 0.88 g per kg of weight, persisted after complete nutritional recobly due to gastric retention of the substrate. Malabsorption of a physiological dose of lactose, 12.5 g, was detected in the mother and step-father while their daughter exhibited normal growth and development and normal lactose absorption at 8 months of age. The H2 breath test proved to be a sensitive, well-tolerated procedure for both adults and young children. Pitfalls, such as delayed gastric emptying, absence of normal bacterial flora, prior use of antibiotics, must be considered in interpreting H2 breath test results in children.

Adult↗
PubMed2001

Relationship between lactose digestion, gastrointestinal transit time and symptoms in lactose malabsorbers after dairy consumption.

BACKGROUND: The relationship of symptoms with objective measurements, as well as some of the mechanisms involved in lactose tolerance after yoghurt consumption, remain unclear. METHODS: The trial had a double-blind design in which 22 lactose malabsorbers received 25 g daily lactose in fresh (living bacteria > 108 cfu/g) yoghurt or heated (< 102 cfu/g) yoghurt for 15 days, followed by a cross-over (15 days) after a wash-out period (14 days). The lactose digestion was determined by the breath H2 test, the gastric emptying (GE) with a 13C-acetate breath test and the revealed transit time (OCTT) by 15N-lactose-ureide test. Subjects reported their gastrointestinal symptoms (GIS) in a validated questionnaire. RESULTS: Breath H2 test indicated more effective lactose digestion after fresh yoghurt intake. The OCTT was shorter after heated yoghurt ingestion as compared with the fresh. There was lower severity of GIS (P < 0.05) after fresh yoghurt intake, and this showed an inverse correlation with OCTT (P < 0.05). CONCLUSIONS: Delayed orocoecal transit time was associated with fewer gastrointestinal symptoms. The improved lactose digestion and tolerance of fresh yoghurt should be mainly attributed to the presence of living bacteria.

Adult↗
PubMed1984

Hydrogen breath test quantification and clinical correlation of lactose malabsorption in adult irritable bowel syndrome and ulcerative colitis.

Lactose malabsorption was studied, by hydrogen breath test, in 72 adults suffering from irritable bowel syndrome, in 20 ulcerative colitis patients, and in 69 healthy subjects. The minimum dose of lactose required to cause a positive breath test was determined, and the symptoms caused and the resulting hydrogen eliminated quantified. A high incidence of lactose malabsorption was shown at standard doses (up to 50 g) in both the healthy subjects (70%) and the patients (86% and 85%, respectively). In the irritable bowel syndrome and the ulcerative colitis groups, symptoms occurred with a smaller quantity of breath hydrogen, presumably in association with a greater individual sensitivity of the colon to distension. The threshold lactose dose was notably lower in the diseased subjects who registered as evidence a prevalence of malabsorption at a 20-g lactose load. The pathogenetic role of lactose malabsorption in the irritable bowel syndrome is emphasized, as is the importance of the personal lactose tolerance.

Adolescent↗
PubMed1979

[Diagnostic significance of lactose level in milk. 1. Lactose level in first quarter milk samples following artificial udder irritation and infection].

Studies were conducted into lactose levels of milk in response to experimentally irritated or artificially infected udder quarters. Milk lactose was found to be suitable as a model parameter by which to objectivate pathophysiological processes in the udder in the context of research, such as experiments on artificial udder infection or testing of udder tolerance of certain medicaments.

Animals↗