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Biomedical subjects

M Gebel

Publications and source records attributed to M Gebel.

At least 55 records · Page 3Linked to original sources
PubMed1997

Colonoscopic allergen provocation (COLAP): a new diagnostic approach for gastrointestinal food allergy.

BACKGROUND: The clinical relevance of gastrointestinal food allergy in adults is largely unknown because the mechanisms are poorly understood and the diagnosis is difficult to confirm. AIMS: To improve the diagnostic means for confirming intestinal food allergy on an objective basis, a new colonoscopic allergen provocation (COLAP) test was developed. PATIENTS: The COLAP test was performed in 70 adult patients with abdominal symptoms suspected to be related to food allergy, and in five healthy volunteers. METHODS: During the COLAP test, the caecal mucosa was challenged endoscopically with three food antigen extracts, a buffer control, and a positive control (histamine). The mucosal weal and flare reaction was registered semiquantitatively 20 minutes after challenge, and tissue biopsy specimens were examined for mast cell and eosinophil activation. RESULTS: No severe systemic anaphylactic reactions were found in response to intestinal challenge. The COLAP test was positive to at least one food antigen in 54 of 70 patients (77%), whereas no reaction in response to antigen was found in healthy volunteers. Antigen induced weal and flare reactions were correlated with intestinal mast cell and eosinophil activation, as well as with patients' history of adverse reactions to food, but not with serum concentrations of total or specific IgE or skin test results. CONCLUSION: The COLAP test may be a useful diagnostic measure in patients with suspected intestinal food allergy and may provide a new tool for the study of underlying mechanisms.

Adolescent↗
PubMed1997

A sonographically guided technique for central venous access.

OBJECTIVE: The internal jugular vein (IJV) is an important access to the central venous system. We compared sonographically guided technique with the traditional anatomic landmark technique for IJV catheterization. SUBJECTS AND METHODS: In a prospective randomized trial, 100 patients underwent routine catheterization of the IJV (50 patients in the sonography group and 50 patients in the anatomic landmark group). Access time, failure rates, and complication rates were evaluated. In addition, the physicians' number of years of experience with catheter insertion was recorded. RESULTS: Access time was markedly shorter with the sonographically guided technique (mean, 15.2 sec; range, 8-76 sec) than with the anatomic landmark technique (mean, 51.4 sec; range, 3-820 sec) (p = .001). The failure rate was significantly lower with the sonographically guided technique (p = .002). Complications were fewer with the sonographically guided technique (neck hematoma, 2% versus 10%; plexus irritation, 4% versus 6%; carotid artery puncture, 0% versus 12%). We found that the number of years of postgraduate clinical training was greater in the group of physicians using the anatomic landmark technique. CONCLUSION: The sonographically guided technique is associated with less risk and less inconvenience for patients, especially critically ill patients, for whom the technique provides fast, safe, and easy IJV catheterization.

Catheterization, Central Venous↗
PubMed1997

Effect of respiration, exercise, and food intake on hepatic vein circulation.

Since the effects of respiration, nutrition, and exercise on blood flow in the hepatic vein are not well understood, the objective of this study was to determine the hemodynamic influence of these factors on hepatic venous circulation using Doppler ultrasonographic tracings. The venous blood flow of the middle hepatic vein was determined during arrested full inspiration, midinspiration, and expiration in 25 healthy subjects. The maximum velocity and the systolic-to-diastolic ratio of the blood flow were measured. The portal vein blood flow velocity was measured in 20 volunteers before and after food intake. The portal vein blood flow and the hepatic vein flow velocity were examined in eight volunteers after exercise. During inspiration, maximum blood flow velocity of the hepatic veins decreased compared to midinspiration (P < 0.001). With expiration the maximum velocity increased (P < 0.001). After food consumption, there was no change in the velocity of the hepatic veins, but the portal vein blood flow increased (P = 0.041). After physical exercises, the maximum velocity of the hepatic venous flow increased, on average, about 148% (P = 0.01), and the portal vein blood flow decreased about 44% (P = 0.027). To achieve standard measurements of hepatic venous blood flow, the state of respiration and physical exertion should be established. The nutritional status had only a minor influence on hepatic vein measurements.

Adult↗
PubMed1996

Quantitative assessment of intestinal eosinophils and mast cells in inflammatory bowel disease.

Previous studies on the frequency of intestinal mast cells and eosinophils in patients with inflammatory bowel disease yielded conflicting results. In the present morphometric study, we quantified mast cells and eosinophils in the lamina propria by histological and immunohistochemical methods in 64 patients suffering from Crohn's disease (33 cases) or ulcerative colitis (31 cases), and in 29 controls. Histological data from 206 biopsies were related to the presence of mucosal inflammation and clinical parameters. The number of eosinophils was increased in patients with inflammatory bowel conditions (mean +/- SE: 331 +/- 44/mm2) as compared to controls (258 +/- 27/mm2), and was dependent on disease activity and drug treatment. Mean mast cell numbers did not differ between patients and controls. However, a reduced mast cell number was found in toluidine blue-stained sections of actively inflamed tissue areas (143 +/- 16/mm2, versus 206 +/- 18/mm2 in non-inflamed tissue). Immunohistochemical studies using antibodies against the granule proteins tryptase and chymase suggest that this decrease in mast cell numbers is due to mast cell degranulation. The present data show that the number of intestinal mast cells and eosinophils is altered in patients with inflammatory bowel diseases, suggesting that both cell types are involved in the pathogenesis of chronic intestinal inflammation.

Adult↗
PubMed1996

Endoscopic management of biliary tract strictures in primary sclerosing cholangitis.

BACKGROUND AND STUDY AIMS: In a subgroup of patients, primary sclerosing cholangitis (PSC) is complicated by high-grade focal strictures of the bile ducts, and this can have an unfavorable influence on the natural course of the disease. The aim of this study was to evaluate the efficacy and safety of endoscopic treatment in this selected patient group. PATIENTS AND METHODS: Twelve symptomatic patients with primary sclerosing cholangitis and major ductal strictures were included in a prospective study of endoscopic treatment. All patients were managed by repeated angioplasty-type balloon dilation and nasobiliary catheter perfusion. A minimum of two treatment sessions was used, and therapy was continued until satisfactory reopening of the strictures was obtained. Routine endoscopic follow-up was performed after three, six, 12, 18, and 24 months, and then at yearly intervals. The efficacy of therapy was assessed by evaluating clinical symptoms, laboratory data, and cholangiograms. RESULTS: The long-term follow-up averaged 23 months (range: 12-50 months). Two to nine (mean: three) treatment sessions were required to obtain satisfactory reopening of major biliary strictures. Eight patients showed considerable and sustained improvement. The mean serum bilirubin, alkaline phosphatase, gamma-glutamyl-transpeptidase, and alanine aminotransferase levels felt significantly by 73% (P = 0.0164), 46% (P = 0.0022), 55% (P = 0.0022), and 58% (P = 0.0022), respectively. The average radiographic stricture score before treatment was 3.2 +/- 0.8 (P = 0.0033). Three patients required liver transplantation seven, 12, and 40 months after the initiation of endoscopic treatment, due to a deterioration in hepatic function or an inability to exclude complex biliary malignancy. No major procedure-related side effects were observed. CONCLUSIONS: Our results suggest that the endoscopic treatment of PSC patients with dominant bile duct strictures is effective, safe, and well-tolerated. However, it is important not to overlook the potential development of cholangiocarcinoma.

Adolescent↗
PubMed1996

[Importance of duplex velocity histograms in the diagnosis of liver cirrhosis].

PURPOSE: A prospective study was carried out to determine the diagnostic value of velocity histograms of hepatic veins in patients with liver cirrhosis and healthy subjects. METHODS: The hepatic veins of ten healthy subjects and ten patients with liver cirrhosis were examined by the Doppler method. The velocity histogram measures the velocity variation at a defined area in the duplex tracing. Within this tracing, the peak, mean, mode and velocity range were measured. RESULTS: A velocity range of 0.02 +/- 0.015 m/s was examined in healthy subjects, and a range of 0.06 +/- 0.013 was examined in liver cirrhosis patients (p < 0.001). The other measurement options showed no significant changes between the healthy subjects and the liver cirrhosis patients (p < 0.05). CONCLUSIONS: Until now, differentiation of the hepatic vein tracings was possible only on a qualitative basis. With the assessment of the velocity range it is possible to obtain a more objective differentiation between the duplex tracing in hepatic veins of liver cirrhosis patients and healthy subjects.

Adult↗
PubMed1996

Squamous cell carcinoma of the liver originating from a solitary non-parasitic cyst case report and review of the literature.

Squamous cell carcinoma of the liver arising from a non-parasitic cyst is a rare entity of a primary liver tumor with an unfavourable prognosis. We report a case of a patient with a cyst in the right lobe leading to upper abdominal symptoms and respiratory discomfort. Malignancy was not suspected from the clinical findings or repeated cytological examination of the cyst fluid. However, the blood stained brown color of the cyst fluid was unusual. Cyst recurrence after six attempts of conservative treatment with sonography guided drainage over a period for more than one year led to laparotomy with cyst unroofing. Because frozen section from the cyst wall revealed the unexpected finding of squamous cell carcinoma right hemihepatectomy was performed during the same operation. The patient is alive more than four years after surgery without cyst or tumor recurrence. The difficulties in establishing diagnosis are confirmed by the review of other reports. In the diagnosis and treatment of symptomatic non-parasitic liver cysts possible malignancy has to be considered. In case of proven carcinoma radical surgery with partial hepatectomy should be performed.

Aged↗
PubMed1996

Diarrhea, massive ascites, and portal hypertension: rare case of a splenic arterio-venous fistula.

Portal hypertension is a result of chronic liver disease in the majority of cases. Rare, potentially curable causes of portal hypertension include vascular conditions such as hepatic or portal venous thrombosis and arterio-portal fistulas. We present the rare case of a spontaneous splenic arterio-venous fistula in a 40 year old multiparous woman. The young woman presented with massive diarrhea, ascites, abdominal pain, and an abdominal machinery type bruit and represents the second ever reported case with diarrhea as presenting symptom of splenic arterio-venous fistula. The diagnosis was confirmed by color Doppler ultrasound. Transfemoral aortography was performed to assess the possibility of catheter embolization. Surgical intervention was initially complicated by collateral arterial tributaries of the fistula and finally resulted in a dramatic recovery with persistent resolution of all symptoms. This case report demonstrates a curable form of portal hypertension that must be considered in acute onset portal hypertension in multiparous women and in the absence of liver disease. A machinery type bruit in the upper left abdominal quadrant represents an important and simple diagnostic symptom found by auscultation. Color Doppler ultrasound represents a non invasive, universally applicable and fast method of establishing the diagnosis. The literature and management of splenic arterio-venous fistulas are reviewed.

Adult↗
PubMed1996

Percutaneous endoscopic gastrostomy in AIDS and control patients: risks and outcome.

OBJECTIVES: Wasting is a major feature of advanced HIV infection. Enteral nutrition via percutaneous endoscopic gastrostomy (PEG) is a safe and efficient therapy in malnutrition, but limited experience exists in wasted HIV patients. Here we report on outcome and risk of PEG-feeding in HIV patients compared with HIV-seronegative patients and with HIV patients without PEG. METHODS: In 47 HIV-infected patients, PEG was placed because of wasting (n = 33), neurologic deficits (n = 11), or dysphagia (n = 3). Clinical, immunological, and nutritional data were compared with those of i) 15 HIV patients who refused PEG placement despite an appropriate indication, ii) 76 HIV patients without signs of malnutrition, and iii) 43 miscellaneous PEG patients. RESULTS: PEG was as safe in HIV-infected as in HIV-seronegative patients. PEG feeding resulted in significant increases of body weight (+3.3 +/- 3.6 kg, p < 0.001), serum albumin concentration (+4.5 +/- 7.2 g/L, p < 0.005), and total iron-binding capacity (+9.5 +/- 11.5 mumol/L, p < 0.001). Moreover, our data indicate that PEG feeding may improve survival in wasted AIDS patients. CONCLUSIONS: PEG feeding is safe and effective in the treatment of the AIDS wasting syndrome. Further prospective investigations are necessary to answer the question of whether treatment of wasting improves patient survival.

Acquired Immunodeficiency Syndrome↗
PubMed1995

[Possibilities and limits of a new color technique: ultrasound angiography--results of the "Heidelberg Round Table Discussion"].

Sonographic diagnostics has been essentially enlarged by blood flow measurements with the color Doppler technique. Nevertheless, the method has certain limitations, especially when employed to visualize extremely slow blood flow velocities, which occur e.g. in malignant tumors due to neovascularization. Recently, a new technique, the so-called angio-color procedure, has been presented, which is supposed to overcome the above-mentioned limitations. The way of coding the signal differs considerably from that in conventional color Doppler: The amplitude is color coded, not the frequency deviations. Results and first experiences with the new procedure in various domains were discussed at a 'Heidelberg Round Table' and are summarized in the present article. In the obstetrics/gynecology there are clear advantages in the representation of blood flow in the placenta. In eutrophic fetuses a blood flow over the entire placental breadth was detected, in dystrophic fetuses, however, only on the margins of the placenta. Conventional color Doppler could not visualize blood flow in the placenta at all. Blood flow assessment in the fetal organs also provided different results with the two procedures: the angio-color method showed color pixels even in the peripheral areas. In 8 malignant breast tumors the same observation was made, the angio-color procedure seemed to visualize more color pixels. In 4 of 6 benign lesions blood flow could be measured with the traditional color Doppler, but in 5 of 6 patients with the angio-color Doppler. This was also observed in ovarian tumors. Angio-color representation of renal transplants with normal function resulted in blood flow information reaching deep into the renal capsule, whereas in cases of renal transplants with impaired function a clearly reduced perfusion was visualized. These differences were not so evident with the conventional Doppler method. In lymph node diagnosis, too, marked differences between malignant and reactive lymph nodes could be visualized. In the diagnosis of arteriosclerotic plaques, blood flow in the residual lumen could also be detected more exactly with the angio-color technique. Color representation of liver tumors also showed a higher color signal density with ultrasound angiography. In summary, ultrasound angiography can provide additional information in the color representation of vessels with slow flow velocities. However, an obvious problem is the unability to quantify detected low blood flow. The new procedure will not replace but usefully complete the established sonographic techniques.

Arteriosclerosis↗
PubMed1995

Which is the best surgery for Budd-Chiari syndrome: venous decompression or liver transplantation? A single-center experience with 50 patients.

The optimal treatment of Budd-Chiari syndrome (BCS) remains an open question. It is still a matter of controversial discussion whether venous decompression or liver transplantation is superior. To elucidate the role and prognosis of both surgical options in our own experience, a consecutive series of 50 patients treated between 1981 and 1993 was retrospectively analyzed. Twelve patients had different types of portosystemic shunts or local decompressive procedures, and transplantation was performed in 43 cases, including five with previous conventional surgery. The overall mortality of 18 of 50 was conventional surgery. The overall mortality of 18 of 50 was concentrated within the early postoperative period, with no patient lost after 1 year. In the venous decompression group, the success rate was only 29%, and treatment failure was closely related to the finding of cirrhosis or technical problems like vascular thrombosis. After transplantation, early complications were rejection, primary nonfunction, or graft necrosis, and contributed significantly to the risk of sepsis. Thirty of 43 liver recipients are currently alive, including four rescued after failed decompressive surgery, with 1- and 10-year survival of 69%, and excellent recurrence-free rehabilitation. These results clearly indicate that patient selection plays a dominant prognostic role in the treatment of BCS. Venous decompression and liver transplantation should both be integrated in a common therapeutic concept, and the individual decision for the preferred approach must be based on the leading clinical symptom: portal hypertension or liver failure, together with the assessment of reversibility of hepatic damage, and the potential of cure of the underlying disease.

Adolescent↗
PubMed1994

Tracheal stenting for malignant tracheoesophageal fistula.

Palliative intubation of the esophagus for a malignant tracheoesophageal fistula is often complicated by difficulty in obtaining a tight seal. We have overcome the problem in three instances by placing a bifurcated, foam-cuffed stent in the trachea.

Aged↗
PubMed1994

Tissue characterization using intelligent adaptive filter in the diagnosis of diffuse and focal liver disease.

In ultrasonic imaging an adaptive two-dimensional filter (ATDF) can suppress randomly generated speckle using the ratio of the local variance to the local mean as the speckle recognition feature (R). The degree of smoothing depends on the difference between the recognition feature in the region to be filtered and the selected reference tissue. We have investigated the clinical application of ATDF for ultrasound B-mode images of liver abnormalities. Using the R values of normal liver as reference values, the ATDF images were displayed. Normal livers (n = 17, R = 2.19 +/- 0.14 M +/- SEM), fatty livers (N = 16, R = 1.89 +/- 0.15) and those with acute hepatitis (N = 10, R = 2.25 +/- 0.18) appeared smooth after application of the adaptive filter, but those diseases with higher R values, such as chronic hepatitis (N = 10, R = 3.04 +/- 0.30), cirrhosis (n = 16, R = 4.44 +/- 0.30), metastases (N = 16, R = 6.43 +/- 0.53) and hepatocellular carcinomas (N = 8, R = 7.92 +/- 0.85), were largely unsmoothed. In conclusion, ATDF allows differentiation of some forms of liver disease and may be helpful in the detection of microfocal echogenic textural lesions.

Adult↗
PubMed1994

Bifurcate tracheal stent with foam cuff for tracheo-esophageal fistula: utilization of reconstruction modes of spiral computed tomography.

Malignant tracheo-esophageal fistulae can be palliated with bifurcate tracheal stents. However, stents must be manufactured according to the individual anatomy. In these instances a foam cuff can result in better sealing of the fistulized area. We present a successful implantation of a bifurcate tracheal stent with foam cuff. To facilitate preoperative planning reconstruction possibilities offered by spiral computed tomography were used.

Adult↗
PubMed1994

Clinical application of three-dimensional sonography in hepatobiliary disease.

The diagnostic value of a novel three-dimensional (3D) ultrasound method was analyzed in 93 patients with chronic liver disease, and was compared with conventional 2D sonography. In 26 of 93 patients (28%) 3D sonography was superior to 2D sonography. 3D sonography improved the assessment of the extent and localization of liver tumors (9/20). In 2 of 5 Budd Chiari patients 3D sonography refined the visualization of vascular thrombi. Correct detection of the number of gallstones and their localization within the biliary tree was enhanced by 3D sonography (8/16), especially in cases of cystic duct and prepapillary stones. The assessment of the extent of biliary tract alterations in primary sclerosing cholangitis was superior in 3D sonography (4/7). In contrast, 3D imaging did not add important information in diffuse liver disease. Our results indicate that 3D imaging is superior to routine sonography in the anatomical assignment of complex vascular and biliary duct alterations, while there is no obvious benefit in diffuse liver disease so far.

Adult↗
PubMed1994

The Budd-Chiari syndrome: clinical presentation and diagnostic findings in 45 patients treated by surgery.

We report on the clinical presentation and diagnostic findings in 45 patients with Budd-Chiari syndrome. The diagnosis was confirmed by histology at the time of liver transplantation (n = 37) or shunt surgery (n = 8). An underlying disorder could be established only in half of the patients, oral contraceptives as predisposing factor were known in 18 cases. Clinically, abdominal pain and distension as well as hepatomegaly and ascites were most frequent findings, whereas changes in laboratory data were more or less unspecific. By use of repeated ultrasound, a definite diagnosis of a Budd-Chiari syndrome could be confirmed in all cases by obligatory demonstration of obstruction or thrombosis of at least one major liver vein. Hepatic venography revealed only one false-negative result. Celio-mesenteric arteriography plus portography, cavography and preoperative liver biopsy did not present additional diagnostic information. These techniques may contribute to treatment planning of portosystemic shunt surgery or hepatic transplantation. In conclusion, the presence of hepatosplenomegaly, ascites, abdominal pain and distension, especially in combination with a known hypercoagulable state, should alert to the possibility of a Budd-Chiari syndrome. Ultrasound is the diagnostic tool of choice. Hepatic venography should only be performed if even repeated ultrasound is not conclusive.

Adolescent↗
PubMed1994

Helicobacter pylori infection and serum pepsinogen A, pepsinogen C, and gastrin in gastritis and peptic ulcer: significance of inflammation and effect of bacterial eradication.

OBJECTIVES: To study the relationship between Helicobacter pylori infection, gastric inflammatory scores, and fasting gastrin and pepsinogen A and C concentrations, and to evaluate the effect of treatment on these parameters. METHODS: Gastrin and pepsinogen A and C concentrations were measured in 36 patients with gastritis, 10 gastric ulcer patients, 12 duodenal ulcer patients, and in 15 subjects with normal gastric mucosa, by standard radioimmunoassay techniques. Fifteen patients with H. pylori infection underwent triple therapy (bismuth subsalicylate, amoxicillin, metronidazole) and were reassessed 1 month later. RESULTS: Fasting gastrin and pepsinogen A and C concentrations were significantly higher in H. pylori-positive gastritis and peptic ulcer patients than in subjects with normal mucosa and in patients with H. pylori-negative gastritis. There was a significant correlation between inflammatory scores and serum gastrin (r = 0.45, p < 0.0001), and pepsinogen A (r = 0.33, p < 0.006) and pepsinogen C (r = 0.55, p < 0.0001) concentrations. Neither sex nor age affected basal gastrin and pepsinogen concentrations. Eradication of H. pylori infection was successful in 12 patients and resulted in a significant fall in serum gastrin and in pepsinogen A and C concentrations, and in a concomitant improvement of the inflammatory scores. Serum peptide levels and gastritis scores were unchanged in those patients in whom H. pylori infection persisted. CONCLUSIONS: These findings suggest that hypergastrinemia and hyperpepsinogenemia are secondary to H. pylori infection and are related to mucosal inflammation.

Amoxicillin↗