Gastrointestinal bleeding in patients with hereditary hemorrhagic telangiectasia

OBJECTIVE

Gastrointestinal bleeding occurs in a number of patients with hereditary hemorrhagic telangiectasia (HHT) and may lead to a high transfusion need. The aim of this study was to estimate the occurrence and severity of gastrointestinal bleeding in a geographically well defined HHT population.

METHODS

All HHT families in the county of Fyn, Denmark, (470,000 population) have been identified. Probands and their first degree relatives, and all descendants from probands for whom one parent had HHT were eligible for inclusion in the study. A total of 77 patients with HHT were identified; of these, 76 patients (mean age: 52 yr) were evaluated and interviewed with regard to gastrointestinal bleeding, that is, a history of either hematemesis or melena. Patients charts were reviewed.

RESULTS

A total of 25 HHT patients (33%) had a history of either hematemesis or melena. Of these, 12 (48%) had received blood transfusions. Seven patients had severe bleeding (that is, > or =6 units of blood within 6 months before inclusion in the study). Endoscopy had been performed in 16 of the 25 (64%) patients. Telangiectatic lesions were documented in nine at upper endoscopy and in one at sigmoidoscopy. Telangiectatic lesions were observed in all patients with severe bleeding, but in two patients epistaxis is likely to have contributed to the anemia. Among 51 HHT patients without a history of gastrointestinal bleeding, only five (10%) had previously received blood transfusions; however, none fulfilled the definition of severe bleeding. In the HHT population 29 patients were > or =60 yr old, but all patients with severe bleeding were > or =60 yr.

CONCLUSIONS

A history of gastrointestinal bleeding is common in patients with HHT (33%). This study documents that 25% of HHT patients > or =60 yr suffer from severe gastrointestinal bleeding.

Markers of coagulation and fibrinolysis as measures of disease activity in inflammatory bowel disease

BACKGROUND

Activation of coagulation and fibrinolysis occurs in patients with inflammatory bowel disease. Our aim was to study the course of a marker for activation of the coagulation cascade, prothrombin fragment 1 + 2 (F1+2), and fibrinolysis, fibrin degradation products (FbDP), in patients with ulcerative colitis and Crohn's disease before and during therapy with glucocorticoids.

METHODS

Twenty-seven patients with active ulcerative colitis and 42 with active Crohn's disease treated with glucocorticoids were studied. Plasma samples were drawn before, during, and at end of therapy or at time of treatment failure. F1+2 and FbDP were measured with commercially available enzyme immunoassays.

RESULTS

Mean base-line concentrations of F1+2 were significantly increased in patients with ulcerative colitis (4.77 +/- 0.50 nmol/l; P < 0.0001) and in Crohn's disease (4.66 +/- 0.59 nmol/l; P < 0.0001) compared with healthy controls (1.57 +/- 0.09 nmol/l). Mean base-line concentrations of FbDP were significantly increased in patients with ulcerative colitis (1264 +/- 161 microg FE/l; P < 0.0001) and in Crohn's disease (491 +/- 51 microg FE/l; P < 0.0001) compared with healthy controls (194 +/- 21 microg FE/l). During treatment with glucocorticoids the plasma concentrations of FbDP decreased in patients with Crohn's disease achieving remission and in patients with ulcerative colitis avoiding surgery but remained unchanged in patients not responding to therapy. In contrast, F1+2 remained increased in patients with Crohn's disease and ulcerative colitis irrespective of outcome.

CONCLUSION

The present data support the concept that coagulation cascade and fibrinolysis is activated in patients with active inflammatory bowel disease. F1+2 and FbDP correlate poorly with the clinical disease activity and acute-phase reactants. The clinical response to treatment with glucocorticoids is accompanied by a decrease in plasma concentrations of FbDP but not in F1+2. FbDP may emerge as a new marker in the assessment of disease activity in patients with inflammatory bowel disease.

Biological variation of International Normalized Ratio for prothrombin times, and consequences in monitoring oral anticoagulant therapy: computer simulation of serial measurements with goal-setting for analytical quality

Oral anticoagulant therapy (OAT) has a well-established efficacy in prophylaxis and treatment of thromboembolic disorders. Because complications are related to intensity of OAT, optimal control of treatment is mandatory. In studies of OAT, as many as 30% of International Normalized Ratio (INR) measurements for prothrombin times fall outside the therapeutic interval. Preanalytical, analytical, and biological variation all contribute to this. Computer simulations of serial INR measurements were performed for various assumed in-treatment setpoints within the therapeutic interval INR 2.0-3.0 and for an "in-treatment within-subject variation" (CV) of 10.1%. Results are presented in difference plots with therapeutic intervals and critical differences. If the in-treatment setpoint is mid-interval (INR = 2.5), only 5% of simulated INR values fall outside the therapeutic interval. Setpoints deviating from the mid-interval and increases in the in-treatment within-subject variation considerably increase the number of observations outside the therapeutic interval and the critical differences. In conclusion, random variation, biological or analytical, and setpoints (targets) deviating from mid-interval explain a substantial number of the INR values outside therapeutic intervals observed in clinical studies. Analytical imprecision should be kept < 5% and analytical bias < +/- 0.2 INR.

Graphical interpretation of analytical data from comparison of a field method with reference method by use of difference plots

Various viewpoints have been offered regarding the appropriate use of scatter plots or difference plots (bias plots or residual plots) in comparing analytical methods. In many of these discussions it seems the basic concepts of identity (within inherent imprecision) and acceptability based on analytical goals (analytical quality specifications) have been forgotten. With the increasing number of Reference Methods in laboratory medicine, these basic concepts are becoming more important in validation of field methods. Here we describe a simple and effective graphical test of these hypotheses (identity and acceptability) by use of difference plots. These plots display the underlying hypothesis before the measured differences are plotted and allow interpretation of the results according to specific criteria. We further describe simple but effective interpretations of the data, when the hypothesis is not fulfilled, by using two data sets drawn from comparisons of field methods for S-creatinine with a Reference Method for this analyte. The difference plot is a graphical tool with related simple statistics for comparison of a field method with a Reference Method, focusing on (a) identity within the inherent analytical imprecision or (b) acceptability within analytical quality specifications. Calculation of the standard deviation of the differences is an indispensable tool for evaluation of aberrant-sample bias (matrix effects).

Serum concentrations of orosomucoid: improved decision-making for tapering prednisolone therapy in patients with active inflammatory bowel disease?

BACKGROUND

The reliability of clinical judgment for the tapering of glucocorticoids in patients with active inflammatory bowel disease has been questioned.

METHODS

The current study compared decision-making strategies on the basis of a combination of disease indices and serum concentrations of orosomucoid (strategy A) and disease indices only (strategy B) for the tapering of prednisolone. Twenty-nine patients with clinically active ulcerative colitis and 59 patients with Crohn's disease and increased concentrations of S-orosomucoid participated. The initial dose of prednisolone was 40 or 75 mg, which was tapered off over a minimum of 6 or 8 weeks.

RESULTS

The tapering schedule was completed in 11 of 44 (25%) patients treated in accordance with strategy A, whereas 28 of 44 patients (64%) and prednisolone completely tapered, in accordance with strategy B. At follow-up 4 of 11 patients (36%) and 17 of 28 patients (61%) treated in accordance with strategies A and B, respectively, had clinical relapse (0.10 > P > 0.05). By means of multiple regression analysis a high serum concentration of orosomucoid and previous disease activity were identified as predictors of relapse.

CONCLUSION

A therapeutic end-point of normalization of an increased level of S-orosomucoid in addition to clinical remission may be difficult to use, as serum concentrations may be continuously increased in spite of clinical remission. However, this goal may still be relevant, as a trend towards higher risk of relapse was found in patients with increased orosomucoid concentrations after completing therapy.

[Legionella infection with rhabdomyolysis]

Rhabdomyolysis complicating infection with Legionella pneumophila has previously been reported and may in some cases have led to acute tubular interstitial necrosis. We report a case of severe Legionnaires' disease complicated with rhabdomyolysis, myoglobinuria and neurological symptoms. Treatment with erythromycin and rifampicin was initiated early in the course of disease. The myoglobinuria was treated with forced diuresis and alkanization and renal failure did not develop. The frequency of rhabdomyolysis as a complication to Legionnaires' disease is not known. In addition, the pathogenesis and possible risk factors have not yet been determined. Considering the seriousness of this complication and until further investigations have been performed we recommend that routine determinations of creatine phosphokinase are performed in the evaluation of these patients.

Selective blockade of leukotriene production by a single dose of the FPL 64170XX 0.5% enema in active ulcerative colitis

5-Lipoxygenase products of arachidonic acid metabolism are thought to play a central role in the secondary amplification of the inflammatory response of several inflammatory diseases, including ulcerative colitis. FPL 64170XX is a selective inhibitor of the enzyme 5-lipoxygenase. Concentrations of leukotriene B4 and prostaglanding E2 in rectal dialysis fluid from 23 males with clinically and sigmoidoscopically active, distally located ulcerative colitis were measured by radioimmunoassays in a double-blind, placebo-controlled, parallel design study before and after rectal administration of an enema containing 0.5% of FPL 64170XX. Repeated measures analysis of leukotriene B4, after adjusting for baseline, showed a significant treatment effect (P = 0.0014). The concentration of leukotriene B4 from rectal dialysates in patients receiving the active drug dropped to 15% (95% confidence interval 5-40%) of the placebo level in the second dialysis following administration of FPL 64170XX 0.5%. By contrast, prostaglanding E2 concentrations doubled (P = 0.0068) in patients receiving FPL 64170XX 0.5% with no change in the placebo group. These findings demonstrate that a single dose of FPL 64170XX 0.5% enema selectively blocks the generation of the 5-lipoxygenase product, leukotriene B4, to a mean of 85% in the target tissue of inflammation. Topical administration of this new leukotriene synthesis inhibitor may prove to be a clinically useful approach to the treatment of active, distally located ulcerative colitis.

Seromarkers of collagen I and III metabolism in active Crohn's disease. Relation to disease activity and response to therapy

Crohn's disease is characterised by gradual development of intestinal fibrotic lesions containing large amounts of collagen type I, III, and V. Measurement of circulating connective tissue metabolites has emerged as a useful tool for assessment of fibroproliferative activity in various diseases. Serum concentrations of procollagen peptides, N-terminal propeptide of type III procollagen (PII-INP), and C-terminal propeptide of type I procollagen (PICP), reflect the synthesis rate of the parent collagens, while the C-terminal telopeptide of type I collagen (ICTP) reflects its degradation. S-PIIINP, S-PICP, and S-ICTP were measured by radioimmunoassays in 29 patients with active Crohn's disease. S-ICTP was significantly increased, median 6.2 micrograms/l (95% CI 5.2 to 8.7 micrograms/l) versus controls 2.6 micrograms/l (2.5 to 2.7 micrograms/l) (p < 0.0001), S-PICP reduced, 100 micrograms/l (80 to 110 micrograms/l) versus 132 micrograms/l (124 to 141 micrograms/l) (p = 0.001), and S-PIIINP did not differ from controls. Patients with sustained clinical remission during prednisolone therapy exhibited an increase in S-PICP (p = 0.0052). S-PIIINP changed significantly (p = 0.0002), however, exhibiting a biphasic pattern. S-ICTP decreased (p = 0.015) in treatment responders but remained above the upper normal limit even when clinical remission had been achieved. Non-responders showed no significant changes in any of the marker molecules of collagen synthesis or degradation. Correlations were found between S-PIIINP and S-PICP (p < 0.005) and S-ICTP (p < 0.02), and between S-ICTP and S-orosomucoid (p < 0.005) and S-C reactive protein (p < 0.02). By contrast, there was no relation between the connective tissue metabolites and Harvey Bradshaw Index. These data provide evidence that collagen I degradation is increased not only in active Crohn's disease, but also in patients entering clinical remission. The concurrent normal/low-normal values of markers of collagen formation may reflect a changed local or systemic elimination of the propeptides.

Interpretation of serial measurements of international normalized ratio for prothrombin times in monitoring oral anticoagulant therapy

Despite careful monitoring of oral anticoagulant treatment (OAT), some international normalized ratio (INR) for prothrombin time values will fall outside the therapeutic range. Considerable changes in serial INR results from OAT patients may be caused by random fluctuation alone, and, for statistical reasons, a fraction of the INR values will fall outside therapeutic range and interfere with dose adjustments. On the basis of therapeutic intervals and statistical evaluation of reference changes, we suggest and discuss an alternative method for interpretation of serial INR measurements. Retrospective evaluation of serial measurements of INR from OAT patients revealed an "overshooting" phenomenon. When a dose was adjusted on the basis of insignificant change in INR value, the subsequent INR value generally fell in the opposite direction. If a further change of dose was initiated because of the new INR value, a similar course in the opposite direction was observed. This "ping-pong" effect renders patients in a fluctuating state of anticoagulation and may introduce increased risk of complications. The suggested method provides an objective criterion for dose adjustments in OAT, which should reduce patients' risk.

Interpretation of serial measurements of international normalized ratio for prothrombin times in monitoring oral anticoagulant therapy

Despite careful monitoring of oral anticoagulant treatment (OAT), some international normalized ratio (INR) for prothrombin time values will fall outside the therapeutic range. Considerable changes in serial INR results from OAT patients may be caused by random fluctuation alone, and, for statistical reasons, a fraction of the INR values will fall outside therapeutic range and interfere with dose adjustments. On the basis of therapeutic intervals and statistical evaluation of reference changes, we suggest and discuss an alternative method for interpretation of serial INR measurements. Retrospective evaluation of serial measurements of INR from OAT patients revealed an "overshooting" phenomenon. When a dose was adjusted on the basis of insignificant change in INR value, the subsequent INR value generally fell in the opposite direction. If a further change of dose was initiated because of the new INR value, a similar course in the opposite direction was observed. This "ping-pong" effect renders patients in a fluctuating state of anticoagulation and may introduce increased risk of complications. The suggested method provides an objective criterion for dose adjustments in OAT, which should reduce patients' risk.

Blockade of leukotriene production by a single oral dose of MK-0591 in active ulcerative colitis

BACKGROUND

5-Lipoxygenase products of arachidonic acid metabolism are thought to play a central role in the secondary amplification of the inflammatory response in a number of human inflammatory diseases, such as ulcerative colitis. MK-0591 (3-(1((4-chlorophenyl)methyl)-3((1,1-dimethyl-ethyl)thio)-5(quinolin+ ++-2ylmethyl-oxy)-1H-indol-2yl)-2,2-dimethyl-propanoate) exerts its effect by binding to the 5-lipoxygenase activating protein, thereby inhibiting the translocation and activation of 5-lipoxygenase.

METHODS

Concentrations of leukotriene B4 (LTB4) and prostaglandin E2 (PGE2) in rectal dialysis fluid, ex vivo biosynthesis of LTB4 in whole blood, and urinary excretion of leukotriene E4 (LTE4) from 16 patients with mild to moderately active distally located ulcerative colitis were measured by use of radioimmunoassays in a double-blind, placebo-controlled parallel-design study before and after oral administration of a 250 mg dose of MK-0591 or placebo.

RESULTS

The mean LTB4 concentration in rectal dialysis fluid was lowered after MK-0591 by > 90% (p < 0.05) from 4 to 8 hours, with a maximum inhibition of 97.5% +/- 3.4% (mean +/- SD) at 20 to 24 hours after dosing, whereas PGE2 was unchanged. In whole blood, MK-0591 decreased ex vivo biosynthesis of LTB4 (p < 0.01), with a maximum inhibition of 96.4% +/- 2.1% at 4 hours after dosing. Urinary excretion of LTE4 was reduced by more than 85% (p < 0.001) from 4 to 48 hours. No adverse events were observed.

CONCLUSION

These findings show that a single oral 250 mg dose of MK-0591 results in nearly complete blockade of systemic leukotriene production and LTB4 formation in the target tissue of inflammation (the rectum). Controlled multiple-dose trials to assess the clinical efficacy of this novel 5-lipoxygenase-activating protein inhibitor seem to be worthwhile.

Treatment of ulcerative colitis with high doses of oral prednisolone. The rate of remission, the need for surgery, and the effect of prolonging the treatment

Treatment of acute attacks of ulcerative colitis in 89 patients with doses of prednisolone above or equal to 40 mg resulted in an overall remission in 67%. Remission rate and colectomy rate were 47% and 42%, respectively, when the disease was severe, 80% and 13% when moderate, and 84% and 3% when mild. The need for surgery was 28% in pancolitis, 11% in left-sided colitis, and 5% in proctitis. After subsequent treatment episodes colectomy was performed in 35% of patients with pancolitis, in 37% with left-sided colitis, and in 5% with proctitis. The median total duration of therapy in patients who went into clinical remission was 4 months, and the median dose just above 3 g prednisolone. Patients who stayed in remission during the follow-up received a significantly higher start dose and total dose of prednisolone in the treatment episode than patients who had a relapse. In 25 patients treatment with doses equal to or above 75 mg of prednisolone was continued beyond 10 days, and 11 patients experienced remission whereas 14 patients had surgery performed. Orally administered corticosteroids produce results comparable to those obtained after the previously suggested intravenous regimen.

[Cesarean section. Changes in frequency and indications in the county of South Jutland during a 10-year period]

During recent years, the frequency of Caesarean section has changed everywhere. Changes during a ten-year period in the Department of Gynaecology in Sønderborg Hospital were registered and involve mainly the groups of imminant foetal death, previous Caesarean section, foeto-pelvic disproportion and placental insufficiency. Alterations in the obstetric services in the County of South Jutland and improved neonatal service have played an important part in development of the frequency of Caesarean section of Sønderborg Hospital.

Morphine inhibits secretion of bicarbonate from the human duodenal mucosa. Possible role of endogenous opioids in the regulation of human duodenal mucosal bicarbonate secretion

Mucus and bicarbonate secreted from the epithelium are thought to be important for the protection of the duodenal mucosa against acid and pepsin, but so far little is known about the regulation of human duodenal mucosal bicarbonate secretion. After isolating a segment of the proximal human duodenum from gastric and pancreaticobiliary secretion we quantified the secretion of bicarbonate from the human duodenal mucosa. The method was evaluated by measurements of basal and prostaglandin E1 analogue-stimulated bicarbonate secretion. The duodenal mucosal bicarbonate secretion was inhibited 70% after intravenous infusion of morphine in a dose of 73.6 micrograms/kg/h and increased after intravenous administration of naloxone. Thus, the inhibition is most likely mediated by mu-receptors, and the results suggest a role of endogenous opioids in the regulation of the secretion of bicarbonate from the human duodenal mucosa.

[Defence mechanisms of the gastroduodenal mucosa. The significance of epithelial and subepithelial factors for the development of acute and chronic ulceration]

Extra-epithelial, epithelial and sub-epithelial defence mechanisms protect the gastroduodenal mucosa against acid and pepsin. The epithelial mechanisms include epidermal growth factor, surface active phospholipids on the luminal membrane of the epithelial cells, sulfhydryl compounds and rapid epithelial restitution after damage. The sub-epithelial mechanisms include mucosal blood flow supplying the mucosa with bicarbonate needed for neutralization of the acid which penetrates the epithelium and the protective effect of the process of acid secretion. Prostaglandins, which partially protect the gastroduodenal mucosa against damaging agents, stimulate several of the abovementioned defensive factors but the precise mechanism of the action of prostaglandins is still unknown. The results of several experiments support the idea of the defensive factors being of importance in the development of acute and chronic gastroduodenal ulceration. At present, the therapeutic possibilities seem to be restricted and nothing indicates that stimulation of the defensive factors, only, is more effective in the treatment of peptic ulcer than inhibition of aggressive factors as acid and pepsin.

Duodenal disappearance rate of acid during inhibition of mucosal bicarbonate secretion

In order to investigate the relation between duodenal mucosal and pancreaticobiliary bicarbonate secretion, we have studied the effect of inhibition of mucosal bicarbonate secretion by indomethacin on the disappearance rate of acid and the concomitant plasma secretin concentrations. 10 healthy subjects were studied twice, with and without indomethacin pretreatment. By means of a double-lumen tube the duodenum was perfused with increasing amounts of acid (0, 3.0, 6.0 and 9.5 mmol/h) and the disappearance rate of acid, pH of duodenal aspirate and plasma secretin were measured. In both experiments nearly all acid, even at the highest acid load, disappeared (pH greater than 6). Inhibition of the duodenal mucosal bicarbonate secretion did not decrease the acid-neutralizing capacity of the human duodenum. In fact, the disappearance rate of acid at the highest acid load was a little greater when mucosal bicarbonate secretion had been inhibited than when not (10.3 +/- 0.5 vs. 9.2 +/- 0.2 mmol/h). The pancreaticobiliary secretion of bicarbonate, as judged by plasma secretin concentrations, increased, however, earlier when mucosal bicarbonate secretion had been inhibited than when not (3.7 vs. 3.0 pmol/l at an acid load of 6.0 mmol/h). This indicates that bicarbonate from the duodenal mucosa normally plays a role in the in lumen neutralization of acid in the human duodenum.

[Defense mechanisms of the gastroduodenal mucosa: the role of mucus and bicarbonate in the development of peptic ulcer]

The existing knowledge of the mucus and bicarbonate production of the gastroduodenal mucosa is reviewed. Mucus and bicarbonate are produced in the surface epithelium of both duodenum and ventricle. The production is regulated by neural stimuli, gastrointestinal hormones and local synthesis of prostaglandins. Several of the factors suspected of being of importance to the development of peptic ulcers also have a negative influence on the production of mucus and bicarbonate. This indicates that mucus and bicarbonate are important in the pathogenesis of peptic ulcer. Two newly registered so-called mucosaprotective anti-ulcer drugs (De-Nol, Succralfat) both exert positive influences on the production of mucus and bicarbonate.