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Biomedical subjects

H A Koetse

Publications and source records attributed to H A Koetse.

13 recordsLinked to original sources
PubMed2006

Combined LDI/SAT test to evaluate intestinal lactose digestion and mucosa permeability.

BACKGROUND: Intestinal mucosal damage causes impaired digestive capacity and increased mucosal permeability. Quantification of damage can be used to improve treatment options. Currently, the Lactose Digestion Index (LDI) and the Sugar Absorption Test (SAT) are used for evaluation. The investigation studied whether both tests could be combined to provide a useful multifunctional test and whether measurements in blood (LDI) could be replaced by measurements in urine. MATERIALS AND METHODS: The LDI (25 g 13C-lactose, 0.5 g 2H-glucose), the SAT (5 g lactulose, 1 g L-rhamnose) and the LDI/SAT combination test were performed in seven lactose-digesting and eight lactose-maldigesting adults. Plasma glucose 13C-enrichment was determined by gas-chromatography/combustion/isotope ratio mass-spectrometry (GC/C/IRMS), 2H enrichment determined by gas-chromatography/mass-spectrometry (GC/MS) and urinary sugars by gas-chromatography (GC). RESULTS: The results of the separate LDI test were not different from those of the LDI/SAT in the lactose-digester group (0.82 +/- 0.06 vs. 0.81 +/- 0.09), nor in the lactose-maldigester group (0.36 +/- 0.12 vs. 0.35 +/- 0.06). A significant correlation was found between the 10-h urinary-lactose/lactulose ratio and the LDI (R2 = 0.71, P < 0.01). There were no differences in the lactulose/L-rhamnose ratio between lactose-digesters and lactose-maldigesters using both the SAT and LDI/SAT tests. CONCLUSION: The LDI/SAT test is a reliable method of measuring digestion and permeability simultaneously. The 10-h period urinary lactose/lactulose excretion ratio following lactose consumption reflects lactose digestive capacity.

Adult↗
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↗
PubMed2001

The 13C/2H-glucose test for determination of small intestinal lactase activity.

To diagnose hypolactasia, determination of lactase enzyme activity in small intestinal biopsy material is considered to be the golden standard. Because of its strongly invasive character and the sampling problems, alternative methods have been looked for. We analysed the 13C-glucose response in serum after consumption of 25 g of naturally enriched 13C-lactose. As an internal standard, 0.5 g of 2H-glucose was added and the 2H-glucose response in serum was measured simultaneously. The studies were performed in healthy volunteers with a background of genetically determined lactase nonpersistence (n = 12; low lactase activity) and lactase persistence (n = 27; high lactase activity). The results were compared with those of the lactose hydrogen breath test, the lactose 13CO2 breath test and the previously described 13C-lactose digestion test. After consumption of 13C-lactose and 2H-glucose, the mean ratio 13C-glucose/2H-glucose concentration in serum at 45-75 min was 0.26 +/- 0.09 in the low lactase activity group and 0.93 +/- 0.17 in the high lactase activity group (P < 0.01). Threshold of the ratio between digesters and maldigesters was calculated as 0.46. Accuracy of the new test was superior to all other tests. We conclude that the 13C/2H-glucose test has the potential of determining the small intestinal lactase activity in vivo and of estimating the amount of lactose which is digested in the small intestine.

Adult↗
PubMed2000

Lactose (mal)digestion evaluated by the 13C-lactose digestion test.

BACKGROUND: The prevalence of genetically determined lactase nonpersistence is based on the results of the lactose H2 breath test. This test, however, is an indirect test, which might lead to misinterpretation. DESIGN: We determined lactase activity in healthy Chinese and Dutch students using a novel 13C-lactose digestion test. The cut-off value of this test was established in a Chinese population with a homogenous genetic background of lactase nonpersistence and was compared with the results obtained in a Caucasian population. Twenty-five grams of a 13C-lactose solution was consumed by 12 known H2-positive and 5 H2-negative Chinese students and 48 Dutch students and, subsequently, 13C-glucose concentration in plasma and H2 excretion in breath were measured. RESULTS: A similar 13C-glucose response curve was found in all Chinese students. The mean response curve in the Dutch students was more pronounced (P < 0.01). The 1 h (peak) plasma 13C-glucose concentration was the best discriminator between lactose digesting and maldigesting subjects. The cut-off level of 2 mmol L-1 13C-glucose in plasma was defined in the H2-positive Chinese students group. Based on the 13C-glucose response the prevalence of lactose maldigestion in the Dutch subjects was 25%; based on the lactose H2 breath test 17%. CONCLUSIONS: Using the 13C-lactose digestion test the results demonstrate a higher prevalence of lactose maldigestion in a Caucasian population than indicated by the results of the H2 breath test. A moderate increase in the plasma 13C-glucose concentration after consumption of 13C-lactose in the young adult Chinese subjects indicates a residual lactase activity in that age group, even when a positive H2 breath test result is obtained. These results indicate that the 13C-glucose concentration in plasma more accurately reflects the small intestinal lactose digestion capacity than the lactose H2 breath test.

Adult↗
PubMed2000

13C-carbohydrate breath tests: impact of physical activity on the rate-limiting step in lactose utilization.

BACKGROUND: 13CO2 breath tests can be used to monitor carbohydrate digestion in the small intestine. However, after ingestion of 13C-substrates, 13CO2 excretion in breath originates from two sources: a digestive/oxidative fraction, derived from the small intestine, and a fermentation fraction, derived from undigested substrate spill-over in the colon. In this study, the determinants of the digestive/oxidative fraction were analysed in order to improve the sensitivity/specificity of the 13C-carbohydrate breath tests. METHODS: 13C-carbohydrate breath tests were performed in healthy adults using 13C-lactose, pre-digested 13C-lactose, 13C-glucose, and 13C-galactose as substrates. The effect of exercise (bicycling, 50 W), increasing the metabolism of digested/absorbed substrate, on the outcome of the test was analysed. RESULTS: In rest, no difference was observed in the 4-h cumulative percentage dose recovered in breath (4-h cPDR) after administration of glucose, pre-digested lactose, and lactose, which were 20.3 +/- 4.5%, 19.2 +/- 5.5%, and 19.9 +/- 4.9%, respectively. The 13CO2 excretion rate after 13C-galactose consumption was significantly slower than after 13C-glucose consumption. Exercise increased 4-h cPDR of 13C-glucose significantly: 76.0 +/- 1.0% vs. 22.7 +/- 2.3%. This effect was also observed using 13C-lactose as substrate: 66.1 +/- 6.2% vs. 19.6 +/- 3.9%. One subject had non-symptomatic lactose maldigestion indicated by a positive H2 breath test. The 13CO2 breath test of this subject in rest was indistinguishable from that of the others (4-h cPDR 16.6 vs. 19.6 +/- 3.9%), whereas the test was clearly indicative during exercise (4-h cPDR 20.5 vs. 66.1 +/- 6.2%). CONCLUSION: In healthy volunteers in rest, glucose oxidation is the rate-limiting step in lactose conversion into 13CO2. Increase of metabolism (for instance, by exercise) can shift this step to intestinal hydrolysis of lactose, making the 13C-lactose breath test more sensitive.

Adult↗
PubMed2000

Variations in colonic H2 and CO2 production as a cause of inadequate diagnosis of carbohydrate maldigestion in breath tests.

BACKGROUND: Lactose maldigestion is usually diagnosed by means of the H2 breath test. When 13C-lactose is used as substrate, a 13CO2 breath test can be performed simultaneously. In an earlier publication we described the relation between both the H2 and 13CO2 exhalation in breath and the measured intestinal lactase activity after consumption of 13C-lactose. We found a discrepancy between both breath test results in 36% of the cases. To investigate the possible cause of these incongruous breath test results, we studied gas production from carbohydrate in the colon, using 13C-lactulose as a non-absorbable substrate. METHODS: Experiments were performed in 21 subjects, by applying 5 different doses of 13C-lactulose. Repeatability studies were performed in six of these subjects, using 10 g substrate (three tests with 1-week intervals). RESULTS: Both the H2 and the 13CO2 excretion in breath varied strongly interindividually and intraindividually after consumption of 13C-lactulose. In both cases no dose-response relation was observed. A significant positive linear relationship was found between H2 and 13CO exhalation (r = 0.45, P < 0.005). Extrapolation of these results to 13C-lactose breath tests indicates that the colonic contribution of 13CO2 production to the total 13CO2 excretion in breath varies but is on the average large enough to cause false-negative 13CO2 breath test results. CONCLUSIONS: Excretion in breath of 13CO2 produced in the colon during a 13C-lactulose breath test correlates with the breath H2 excretion. This could explain the occurrence of false-negative 13CO2 lactose breath tests when colonic gas production is high and false-negative lactose H2 breath test results when gas production is low. It can also explain the improved sensitivity of the combined H2/13CO2 lactose breath test compared with both breath tests alone.

Adult↗
PubMed1999

Non-invasive detection of low-intestinal lactase activity in children by use of a combined 13CO2/H2 breath test.

BACKGROUND: The aim of the study was to diagnose hypolactasia with a higher accuracy than with the traditional H2 breath test. METHODS: We used a combined 13C-lactose 13CO2/H2 breath test, which was performed in 33 patients in whom lactase activity was measured. RESULTS: Lactase activity was reduced in 13 cases. The sensitivity and specificity of the H2 test were 54% and 90%; those of the 13CO2 test 69% and 70%. False-negative results did not always occur in the same patients. In five of six patients with both test results abnormal, lactase activity was low. In 13 of 15 patients with both test results normal, lactase activity was normal. In 6 of 12 cases with only 1 test abnormal, lactase activity was low. CONCLUSION: The combined H2/13CO2 breath test (sensitivity, 85%; specificity, 65%) is more adequate for diagnosis of hypolactasia than the H2 breath test alone.

Adolescent↗
PubMed1999

Vertebral osteomyelitis associated with cat-scratch disease.

We describe a patient with vertebral osteomyelitis and paravertebral soft-tissue collections associated with cat-scratch disease (CSD). Diagnosis was established on the basis of histologic examination and serological and polymerase chain reaction (PCR) tests. Treatment consisted of administration of antibiotics, and although skeletal lesions were persistently evident on radiography the patient showed complete clinical recovery. In addition, 15 cases of documented osteomyelitis associated with CSD are reviewed.

Cat-Scratch Disease↗
PubMed1995

Doppler ultrasound and angiography of the vasculature of the liver in children after orthotopic liver transplantation: a prospective study.

Despite the availability of Doppler ultrasound, angiography still forms part of the protocol for evaluating children after orthotopic liver transplantation (OLT) at our department. To investigate whether Doppler ultrasound is a reliable method for evaluating the patency of the hepatic artery, portal vein, inferior vena cava, and the anastomotic site of the portal vein in children after OLT, we performed a prospective study in which Doppler ultrasound was compared with angiography in 38 children with 40 transplants (ten examinations on clinical demand and 49 examinations according to protocol). Good correlation was found in relation to demonstrating a patent hepatic artery (sensitivity 96% and specificity 100%). Two false-negative Doppler ultrasound results were attributable to technical difficulties and rejection. For evaluating the patency of the portal vein, Doppler ultrasound agreed with angiography in 58 of the 59 examinations (98%). The one and only false-positive angiography result was explained by inadequate opacification. Doppler ultrasound visualized stenosis of the portal vein three times more often than angiography. In seven children, Doppler ultrasound findings suspicious of pathology of the inferior vena cava were confirmed using cavography or surgery. Doppler ultrasound proved to be a reliable technique for evaluating the patency of the hepatic artery, inferior vena cava, and portal vein and the anastomotic site of the portal vein.

Adolescent↗
PubMed1993

[Liver transplantation in children].

The liver transplant programme has been initiated after the first good results of the adult transplant programme have been obtained. Initially a few children were transplanted yearly and the lower age limit was 3 years. However, the good results and the introduction of reduced size liver transplants made liver transplantation even in infants possible. In this paper the results are presented of the first 40 children who got a liver transplant.

Child↗
PubMedDate not supplied

Preoperative assessment of the portal vein and hepatic artery in children with end-stage liver disease: is selective angiography still necessary?

BACKGROUND: Selective angiography involves increased risk for children and may cause vascular complications. The aim of this study was to determine whether selective angiography is still necessary for viewing the portal vein and hepatic artery. METHODS: Doppler ultrasound, abdominal aortography, and selective angiography were performed and interpreted independently in 62 children (median age = 1 year 3 months), with end-stage liver disease, who were candidates for orthotopic liver transplantation. RESULTS: Selective angiography agreed with the Doppler ultrasound findings of patency, flow direction, and diameter of the extrahepatic portal vein in 84%, 73%, and 79% of the children, respectively. Important additional information was obtained from selective angiography in only five of the 62 children (8%). Selective angiography showed an anomaly of the hepatic artery in 21 of the 62 children (33%). In 18 out of these 21 children (85%), an anomaly of the hepatic artery was already visible on the abdominal aortogram. CONCLUSION: Selective angiography did not play any significant role in the detection of an anomaly of the hepatic artery and should only be done if the Doppler ultrasound findings of the portal vein are inconclusive or if abdominal aortography cannot provide reliable information about the hepatic artery. For the evaluation of the portal vein and hepatic artery, we recommend Doppler ultrasound and abdominal aortography, a less invasive angiographic procedure.

Female↗