Carine Deprez

Detection of Helicobacter pylori infection in children with a standardized and simplified 13C-urea breath test.

BACKGROUND The 13C-urea breath test, a reliable noninvasive method of detection of Helicobacter pylori in adults, needs validation in children. METHODS In order to evaluate the diagnostic accuracy of 13C-urea breath test in children, the results of this test performed in 144 children were correlated with the histology and culture of contemporaneous gastric (antral and fundic) biopsy specimens. The test was performed with 2 mg/kg body weight 13C-Urea (maximum, 100 mg) ingested after a fat-rich test meal. Samples of expired breath taken at 0, 5, 10, 20, and 30 minutes were assayed with mass spectrometry. Results were considered positive when the curve of excretion of labeled carbon dioxide in the expired breath increased by 5%O or more above the baseline. RESULTS Discrepancies in H. pylori status were observed in 14 children. To improve and simplify the test, the results were reanalyzed using different cutoff values for each sampling time. The best results, with sensitivity of 95.7% and specificity of 95.2%, were obtained with a cutoff of 3.5%O at 20 minutes. CONCLUSIONS The 13C-urea breath test is a reliable method for the noninvasive detection of H. pylori infection in children. The test can be simplified and its accuracy improved using only the 0- and 20-minute breath samples and a cutoff of 3.5%O instead of the classical 5%O used in adults. The need for modification of the cutoff value may reflect the higher production of endogenous CO2 in children.

Effect of antimicrobial therapy on the specific serological response to Helicobacter pylori infection

The systemic immune response toHelicobacter pylori was studied in 247 infected adult patients before antimicrobial therapy and at different intervals following therapy. Endoscopy with simultaneous collection of biopsies was performed in all patients immediately before treatment, 4 to 6 weeks after the end of therapy and 6 to 12 months later. A14C-urea breath test was performed 3 to 6 months after the end of treatment. Biopsy specimens were cultured and examined histologically using Giemsa stain. Sera were tested forHelicobacter pylori IgG antibodies with a commercial enzyme immunoassay using species-specific antigens. Overall,Helicobacter pylori was eradicated in 120 patients while the other 127 remained infected with the organism. The follow-up period ranged from 4 weeks to 33 months (mean 10.2 months). Pretreatment IgG levels did not differ significantly between the two groups of patients. Six weeks after the end of treatment a slight but definite decrease in the IgG antibody levels was seen irrespective of treatment success. In the 127 patients who remainedHelicobacter pylori-positive, the level of IgG antibodies remained stable or increased with time. A continuous fall in antibody levels was observed following bacterial eradication in the other 120 patients, but the difference in antibody levels between treatment responders and nonresponders became significant only more than six months after the end of treatment (p=0.001). Serological testing may be useful for monitoring the outcome of long-term treatment ofHelicobacter pylori infection and obviate the need for endoscopy.

Use of a urea breath test versus invasive methods to determine the prevalence of Helicobacter pylori in Zaire

The prevalence ofHelicobacter pylori infection in Zaire was determined by means of a [14C] urea breath test in 133 asymptomatic subjects, by culture and histological examination of biopsies in 324 consecutive endoscopy patients with chronic epigastric complaints, and by both the breath test and culture/histology in a subset of 92 patients. Sixty healthy Belgian students or hospital laboratory workers were also included for comparison. The prevalence ofHelicobacter pylori was significantly higher in asymptomatic Zairian subjects (77.4 %) than in the Belgians (30 %; p<10−6). Infection was also acquired much earlier in life in Africans, 66% of the children aged 5 to 9 years already being infected versus none of the Belgian subjects below the age of 20 years. In Zaire, however, the prevalence ofHelicobacter pylori in patients with gastroduodenal disorders (87.5 %) was similar to that in the group of asymptomatic subjects (77.5 %) after adjustment for age and other epidemiological parameters (gender, place of residency, education level, smoking and drinking habits) in a multivariate analysis. The high rate of acquisition ofHelicobacter pylori infection in Zaire emphasizes the need to consider the baseline prevalence ofHelicobacter pylori in a defined population when studying its association with various diseases.

Listeria monocytogenes hepatitis in a liver transplant recipient: a case report and review of the literature

Listeria is an uncommon cause of hepatitis in adults. We report the case of a liver transplant recipient who presented with a clinical picture of acute hepatitis, 8 months after grafting. Blood cultures yielded Listeria monocytogenes. The patient made a full clinical recovery after adequate antimicrobial therapy (ampicillin and gentamicin intravenously for 4 weeks). Hepatitis was attributed to the Listeria infection. We believe this is the first reported case of Listeria hepatitis in an organ transplant recipient.

NF‐κB Activation and Severity of Gastritis in Helicobacter pylori‐Infected Children and Adults

In contrast to adults, Helicobacter pylori gastritis in children is reported as milder and ulcer disease as uncommon, but unequivocal data are lacking.

Chemotherapy-induced nuclear alterations of morphologic and genomic characteristics in a human colon cancer grafted onto nude mice

PURPOSE: A human Dukes B colonic adenocarcinoma was grafted onto 40 nude mice. The mice were divided into four groups, one control and three representing experimental conditions. Animals in the three experimental groups received either adriamycin (ADR), 5-fluorouracil (5-FU), or camptothecin (CPT) over a 25-day period beginning 34 days after grafting. Control animals received saline on an identical schedule. Animals were killed 105 days after grafting. METHODS: The effect of therapy was assessed by three techniques: 1) tumor size was periodically measured during the life of the animals, 2) modifications of APC, Ki-ras, and p53 genes were studied by polymerase chain reaction, dotblot analysis, restriction analysis, and DNA sequencing, and 3) image cytometry of Feulgen-stained material was used to characterize 15 parameters describing morphometric, densitometric, and textural features of tumor nuclei. RESULTS: When compared with controls, tumor growth (size) was maximumly suppressed by treatment with CPT (P<-0.001). Growth was inhibited significantly by treatment with 5-FU (P<-0 0.01); no statistical difference in tumor size was observed between controls and animals treated with ADR. Modifications of APC, Ki-ras, and p53 genes were not observed; however, treatment did inhibit amplification of APC and p53 genes. CONCLUSIONS: The 15 morphonuclear parameters were assessed to define populations of cell nuclei altered by chemotherapy. Although CPT maximally suppressed growth, it did not alter nuclear morphology when compared with controls. Treatment with either 5-FU or ADR resulted in nuclear morphologic alterations defined as distinct populations using multivariate analysis. Nonsupervised linear discriminant analysis was used to quantify the relative proportions of these populations. Four morphonuclear parameters were identified, which discriminated nuclei exposed to either ADR or 5-FU from controls.

Neoplastic diseases after liver transplantation

From January 1985 to January 1995, 125 adult patients underwent 135 liver transplantations (OLT). Hundred of them survived more than 3 months.

Diagnostic précoce des récidives anastomotiques après chirurgie pour cancer rectal: utilité de l'échoendoscopie

RésuméLe staging préopératoire des adénocarcinomes rectaux par endoscopie, radiologie ou CT scan est généralement très décevant à la fois dans la détermination du degré d’infiltration pariétale et dans la détection des adénopaties. De même, le diagnostic de récidive locale par les mêmes méthodes est bien souvent tardif et les chances de réintervention à visée curative sont très minces.Le but de la présente étude est de déterminer l’apport de l’échoendoscopie dans le diagnostic précoce des récidives locales.Durant une période de 40 mois, nous avons réalisé 136 échoendoscopies rectales (nous avons utilisé les échoendoscopes GF-UM2, GF-UM3 et CF-UM3) chez 81 patients dans le cadre d’un suivi après resection antérieure du rectum pour adénocarcinome. L’examen réalisé tous les 6 mois était centré sur la suture et les 10 cm de part et d’autre de celle-ci.Dans ce groupe de 81 patients, l’échoendoscopie a permis de suspecter une récidive locale dans 23 cas:— 14 patients ont bénéficié d’une 2e intervention avec confirmation de la récidive dans tous les cas.— 7 patients n’ont pas pu être réopérés pour différentes raisons.— 1 patient ne présente toujours pas de signe de récidive 20 mois après une échoendoscopie pourtant positive (1 faux positif).— 1 patient montrait à 2 reprises des signes de récidive mais a exigé un troisième examen avant d’accepter une réintervention. 58 patients n’avaient pas de signe échoendoscopique de récidive, aucun faux négatif n’a été démontré.Diverses modifications peuvent être mises en évidence dans la région anastomotique mais seule une image nodulaire hypoéchogène — dans la sous-muqueuse ou la muscularis propria — a une valeur diagnostique.Nos résultats montrent que l’échoendoscopie est une des meilleures méthodes dans le staging préopératoire des tumeurs rectales. De plus l’échoendoscopie est dans nos mains une méthode sensible et spécifique dans la détection précoce des récidives locales; ce diagnostic précoce permet une réintervention à visée curative.SummaryPreoperative staging of rectal carcinoma by endoscopy, conventional radiology or CT scan is usually very disappointing for both depth of the infiltration into the rectal wall or perirectal tissues and in detection of parietal lymph nodes. In the same way, local recurrences are diagnosed too late by the same methods and chances for curative reintervention are very low.The aim of this study is to evaluate the clinical value of EUS in early diagnosis of local recurrence.For 40 months, 136 EUS were performed [with the Olympus GF-UM2, GF-UM3 or CF-UM3 echoendoscope (7.5 MHz or 12 MHz)] in 81 patients as follow-up after surgical resection of a previous rectal carcinoma. We performed EUS examination of the rectal suture and 10 cm above and below, every 6 months.In the post-operative follow-up group of 81 patients 23 cases of recurrence were suspected by EUS,— 14 underwent second look surgery, with confirmation of the diagnosis in all of them (only 5 of 14 were positive at endoscopic biopsy),— 7 patients did not undergo for second look surgery— 1 had no evidence of recurrence 20 months after EUS.— 1 patient had 2 positive EUS but negative biopsies, the patient wanted like to have a third EUS before surgery. 58 patients demonstrated no recurrence at EUS (no false negative).Various abnormalities can be observed in the suture area but only hypoechoic nodule -usually in the submucosa or muscularis propria — is of diagnostic value.Our results show that EUS is one of the best procedures currently available for assessing parietal involvement and staging of rectal carcinoma. EUS might be able to guide therapeutical options.EUS is a sensitive method to early diagnose local recurrence and lets the surgeon the opportunity for a second surgical — maybe curative — resection.

Gastrite associée au Campylobacter pylori: essai thérapeutique en double-insu amoxycilline versus placebo

RésuméUne étude contrôlée en double aveugle (amoxycilline vs placebo) a été réalisée chez des adultes porteurs d’une gastrite antrale associée à une infection à C. pylori. Dans la première partie de cette étude, les patients ont été traités par sirop d’amoxycilline (2 x1 gr) ou de placebo en deux prises quotidiennes pendant une semaine. Vingt deux patients ont reçu de l’amoxycilline et vingt trois du placebo. Après traitement, l’infection à C. pylori avait disparu chez 91 % (20/22) des patients traités par amoxycilline contre 16 % (4/23) chez les patients traités par placebo (p < 0.001). La gastrite active de l’antre a disparu chez 15/22 (68 %) patients dans le groupe amoxycilline mais chez seulement 2/23 (16 %) patients dans le groupe placebo (p < 0.001). Aucune amélioration significative n’a été observée en ce qui concerne la Symptomatologie et l’aspect endoscopique. Dans la deuxième partie de cette étude (simple aveugle), 19 patients devenus C. pylori négatifs après une semaine de traitement ont ensuite reçu du sirop placebo pendant 2 semaines: une réapparition de l’infection à C. pylori associée à une aggravation très significative de score histologique de la gastrite a été observée chez tous les patients. A l’inverse, 18 patients restés positifs après une semaine ont ensuite été traités en simple aveugle par sirop d’amoxycilline pendant 14 jours: la disparition du C. pylori, objectivée à la fin de cette période chez 13 d’entre-eux (72 %), était corrélée à une nette amélioration du score histologique de la gastrite. Parmi ces 13 patients, 8 ont été recontrôlés après un mois et tous présentaient à nouveau une infection à C. pylori et une aggravation significative des lésions de gastrite à l’histologie.Ces résultats montrent que le sirop d’amoxycilline à la dose de 2g/jour est efficace dans le traitement de la gastrite active associée à l’infection à C. pylori mais ne permet pas de prévenir les rechutes qui surviennent chez tous les patients dans le mois qui suit l’arrêt du traitement.SummaryA double-blind, placebo-controlled treatment study was performed in adults with antral gastritis associated with C. pylori. Patients received 20 ml of a placebo or an amoxycillin suspension (1g) two times daily for 8 days. Twenty-two patients received amoxycillin and twenty-three received a placebo. At the end of therapy 91 % (20/22) of patients treated with amoxycillin demonstrated clearance of the organism from the antrum compared to 16 % (4/23) in the placebo group (p < 0.001). Active antral gastritis resolved in 68 % (15/22) of patients in the amoxycillin group versus only 9 % (2/23) in the placebo group (p < 0.001). No significant improvement was observed in the assessment of clinical symptoms and endoscopic appearance. Reappearance of C. pylori and significant aggravation of the histological score was observed after 2 weeks in 100 % (19/19) of patients who demonstrated bacterial clearance after 8 days and had then received placebo for 14 days. Conversely, eighteen patients (not cleared from their bacteria after 8 days) received amoxycillin in single blind for 14 days. CLearance of bacteria associated with improvement or resolution of active gastritis was observed in 72 % (13/ 18) of patients. In this subgroup, 100 % (8/8) of patients observed at follow-up 1 month after stopping therapy were recolonized with C. pylori and again had histological active gastritis.These results indicate that amoxycillin suspension 2 g daily for 1 or 2 weeks is effective in treating active antral gastritis associated with C. pylori, but not in preventing relapses, which occur in all patients within one month after therapy.