[VIPoma : a rare etiology of diarrhea with hypokalemia]. / VIPome : étiologie rare d'une diarrhée hypokaliémiante.

VIPoma or Verner Morrison syndrome is a very rare disease with an incidence rate of 1 case per 10 000 000 person-years. It is a neuroendocrine tumor issue from ß-pancreatic islets leading to profuse diarrhea, hypokalemia and gastric achlorydria due to secretion of vasoactive intestinal polypeptide (VIP) hormone. Diagnosis is based on histology of tumor and the dosage of VIP in a blood sample. Somatostatin analog is a simple and efficient treatment for diarrhea. Curative treatment with surgery could be proposed for a localized disease. For disseminated disease, there are different treatments and a multimodal assessment that should be discussed in a multidisciplinary team might be curative.

Le VIPome ou syndrome de Verner Morrison est une maladie très rare, avec une incidence annuelle estimée à 1/10 000 000 habitants. Il s'agit d'une tumeur neuroendocrine issue des îlots ß pancréatiques qui sécrète une hormone appelée vasoactive intestinal polypeptide (VIP), à l'origine d'une achlorhydrie gastrique et de diarrhées profuses entraînant une hypokaliémie. Le diagnostic est posé à partir d'une analyse anatomopathologique de la tumeur et du dosage du VIP sanguin. Le traitement symptomatique par les analogues de la somatostatine est efficace sur la diarrhée. Un traitement curatif par la chirurgie peut être proposé pour une maladie tumorale localisée. Pour les maladies disséminées, différentes modalités thérapeutiques existent et dans certains cas une approche multimodale discutée dans un colloque spécialisé peut être curative.

Long-standing type II diabetes mellitus is not a risk factor for slow gastric emptying in critically ill patients.

OBJECTIVE: Delayed gastric emptying (GE) is common both in critical illness and in patients with diabetes mellitus (DM). The effect of DM on the incidence of slow GE in these patients is unknown. We evaluated the effect of DM on liquid GE in critically ill patients. METHODS: Retrospective analysis of GE using a standard [13C]octanoic acid breath test in 12 type 2 DM patients compared with (a) 44 critically ill patients without DM, including (b) a subgroup of 15 age- and sex-matched patients and (c) 15 healthy volunteers. We determined the gastric emptying coefficient (GEC) and the gastric half-emptying time (t50). Mean APACHE II scores, blood glucose levels and use of morphine were similar between patient groups. RESULTS: GE was faster in critically ill patients with DM (t50 122 +/- 11 min, GEC: 3.8 +/- 0.3) than in patients without DM (t50 168 +/- 16 min, GEC 2.8 +/- 0.1) and in age- and sex-matched controls (t50 165 +/- 13 min, GEC 2.7 +/- 0.2) and was similar to that in healthy volunteers (t50 148 +/- 13 min, GEC 3.5 +/- 0.1). The proportion of patients with slow emptying (GEC < 3.2) was greater in non-DM (all = 56%, matched = 60%) than in DM patients (25%) and healthy subjects (26%). CONCLUSION: Long-standing type diabetes mellitus is not a risk factor for slow GE in critically ill patients.

Distal small bowel motility and lipid absorption in patients following abdominal aortic aneurysm repair surgery.

AIM: To investigate distal small bowel motility and lipid absorption in patients following elective abdominal aortic aneurysm (AAA) repair surgery. METHODS: Nine patients (aged 35-78 years; body mass index (BMI) range: 23-36 kg/m(2)) post-surgery for AAA repair, and seven healthy control subjects (20-50 years; BMI range: 21-29 kg/m(2)) were studied. Continuous distal small bowel manometry was performed for up to 72 h, during periods of fasting and enteral feeding (Nutrison). Recordings were analyzed for the frequency, origin, length of migration, and direction of small intestinal burst activity. Lipid absorption was assessed on the first day and the third day post surgery in a subset of patients using the (13)C-triolein-breath test, and compared with healthy controls. Subjects received a 20-min intraduodenal infusion of 50 mL liquid feed mixed with 200 microL (13)C-triolein. End-expiratory breath samples were collected for 6 h and analyzed for (13)CO(2) concentration. RESULTS: The frequency of burst activity in the proximal and distal small intestine was higher in patients than in healthy subjects, under both fasting and fed conditions (P<0.005). In patients there was a higher proportion of abnormally propagated bursts (71% abnormal), which began to normalize by d 3 (25% abnormal) post-surgery. Lipid absorption data was available for seven patients on d 1 and four patients on d 3 post surgery. In patients, absorption on d 1 post-surgery was half that of healthy control subjects (AUC (13)CO(2) 1323+/-244 vs 2646+/-365; P<0.05, respectively), and was reduced to the one-fifth that of healthy controls by d 3 (AUC (13)CO(2) 470+/-832 vs 2646+/-365; P<0.05, respectively). CONCLUSION: Both proximal and distal small intestinal motor activity are transiently disrupted in critically ill patients immediately after major surgery, with abnormal motility patterns extending as far as the ileum. These motor disturbances may contribute to impaired absorption of enteral nutrition, especially when intraluminal processing is necessary for efficient digestion.

Erythromycin dose of 70 mg accelerates gastric emptying as effectively as 200 mg in the critically ill.

OBJECTIVE: To compare the effectiveness of 70-mg and 200-mg doses of intravenous erythromycin in improving gastric emptying in critically ill patients. DESIGN: Gastric emptying was measured on consecutive days; day 1 (pre-treatment), day 2 (post-treatment) after an intravenous infusion of either 70 or 200 mg erythromycin or saline placebo (0.9%), in a randomized double-blind fashion. SETTING: Mixed medical/surgical intensive care unit, tertiary referral. PATIENTS AND PARTICIPANTS: Thirty-five randomly selected, mechanically ventilated, enterally fed critically ill patients (median APACHE II score 19 on admission). INTERVENTIONS: On day 2 either 70 or 200 mg erythromycin or saline was administered intravenously over 20 min. MEASUREMENTS AND RESULTS: Gastric emptying was measured using the [13C]octanoic acid breath test. The gastric emptying coefficient (GEC) and half-emptying time (t1/2) were calculated from the area under the 13CO2-recovery curve. Pre-treatment gastric emptying measurements were similar in all three patient groups. Treatment with both doses of erythromycin significantly reduced the gastric t1/2: 70 mg, 98 min (IQR 88-112); 200 mg, 86 min (75-104); vs. placebo, 122 min (102-190) (p<0.05). The GEC was higher with both doses of erythromycin: 70 mg, 3.8 (3.3-4.0); 200 mg, 4.0 (3.6-4.2); vs. placebo, 2.9 (2.5-3.7) (p<0.05). There was no difference in gastric emptying post-treatment between the two doses of erythromycin. The effect of erythromycin was greatest in patients with delayed gastric emptying. CONCLUSIONS: Treatment with 70 and 200 mg intravenous erythromycin are equally effective in accelerating gastric emptying in the critically ill.

Evaluation of the 13C-triolein breath test for fat malabsorption in adult patients with cystic fibrosis.

BACKGROUND AND AIMS: A simple non-invasive test not requiring the use of radioactive isotopes is required to assess fat malabsorption in adult cystic fibrosis (CF) patients. Breath tests using substrates labeled with 13C meet these conditions. The 14C-triolein breath test is sensitive and specific for measuring fat malabsorption, but involves radiation exposure. The aim of this study was to examine the utility of a test using a 13C label and to determine whether pancreatic replacement therapy would return the test to the values of a normal control group. METHODS: 13CO2 recovery was assessed after an overnight fast in six adult patients with CF, both with and without pancreatic enzyme replacement therapy (PERT) in the usual dose for a light snack, in a randomized order, on different days. Studies were also performed in eight healthy volunteers after oral ingestion. Subjects drank 50 mL of a liquid meal mixed with 200 microL 13C-triolein and breath samples were collected by blowing through a straw into collection tubes every 30 min for 6 h. The effect of gastric emptying was assessed by comparison of oral ingestion with intraduodenal infusion. Intra-individual variability was assessed in nine volunteers by repeating the breath test after drinking the test meal on a separate day. RESULTS: Compared with healthy subjects there was virtually no recovery of 13CO2 in CF patients without PERT. The median (interquartile range) cumulative percentage dose recovery (cPDR) at 6 h was 3% (0-8) in CF patients compared with 28% (22-41) in healthy controls (P < 0.01). Fat absorption was normalized (37%) (36-43) after ingestion of PERT. Gastric emptying delayed the peak in 13CO2 recovery, but there was no difference in the cPDR at 6 h. There was no difference in recovery between days 1 and 2. CONCLUSIONS: The 13C-triolein breath test is a simple and reproducible method to measure fat malabsorption. The test provides a screening technique for fat malabsorption in adult CF patients and may be useful for monitoring the lowest effective dose of PERT.