The role of gastrointestinal endoscopy in long-distance runners with gastrointestinal symptoms

BACKGROUND: Exercise-related gastrointestinal symptoms are not uncommon among athletes. The occurrence of gastrointestinal bleeding has been reported, especially in long-distance runners. We studied gastrointestinal mucosal damage, using gastrointestinal endoscopy, in competitive long-distance runners. Gastrointestinal blood loss and anaemia before and after running were also assessed. METHODS: Sixteen competitive long-distance runners (all men; age range 16-19 years) participated in the study. All runners completed a symptom questionnaire prior to a 20 km race. Stool occult blood and haematological studies (haemoglobin, haematocrit, serum iron, total iron-binding capacity [TIBC] and ferritin) were performed before and immediately after the race. Gastrointestinal endoscopy was performed to assess macroscopic changes. Colonoscopy was also performed on the patients who had positive stool occult blood before or after the race. RESULTS: Gastrointestinal symptoms were frequently experienced by the runners. Gastritis (n = 16), oesophagitis (n = 6) and gastric ulcer (n = 1) were found at gastroscopy. Colonoscopy was performed on four patients who had positive stool occult blood. One had multiple erosions at the splenic flexure and one had a rectal polyp. Five runners had anaemia, and all of these had at least one endoscopic lesion (three gastritis, two oesophagitis and one multiple erosion at the splenic flexure). There were significant changes in the following haematological parameters after the race: iron (decreased, P = 0.02), ferritin (decreased, P = 0.001) and TIBC (increased, P = 0.00005). CONCLUSIONS: Gastrointestinal symptoms and gastrointestinal mucosal damage are prevalent among long-distance runners. Prior to treatment, gastrointestinal endoscopy should be considered in long-distance runners with gastrointestinal symptoms and/or anaemia.     

Gastrointestinal blood loss associated with running a marathon

Gastrointestinal bleeding has been observed in long-distance runners. We prospectively studied participants of the Eighth Annual Marine Corps Marathon to determine the incidence of gastrointestinal blood loss associated with long-distance running. Of 600 runners contacted, 125 (21%) returned a questionnaire as well as pre- and postmarathon stool specimens. Stool specimens converted from Hemoccult negative to positive in 29/125 (23%) of the participants, indicating that running the marathon was associated with gastrointestinal blood loss (P<0.001). The incidence of this conversion (negative to positive) was significant for both males (N=68,P<0.001) and females (N=57,P<0.05). Gastrointestinal bleeding appeared to be independent of age, race time, abdominal symptoms, and the recent ingestion of aspirin, vitamin C, or steak.The opinions and assertions contained herein are the private views of the authors and are not to be construed as official policy or as reflecting the views of the Department of the Army or the Department of Defense.     

Effect of cimetidine on marathon-associated gastrointestinal symptoms and bleeding

Occult gastrointestinal bleeding occurs in 8–30% of marathon runners. We hypothesized that cimetidine would decrease bleeding by reducing acid-mediated injury and conducted a blinded, placebo-controlled prospective trial to determine the impact of cimetidine on gastrointestinal symptoms and bleeding during a marathon. Thirty participants in the 1989 Marine Corps or New York City marathons completed pre- and postrace: (1) a questionnaire evaluating demographic, medication usage, training history, and gastrointestinal symptoms; (2) three consecutive stool Hemoccult (HO) cards; and (3) a stool Hemoquant (HQ). Fourteen runners (CR) took 800 mg of cimetidine by mouth 2 hr before the start and 16 runners (PR) took placebo. Three subjects were HO+ prerace and were not analyzed. Three subjects failed to take drug as directed and were analyzed as PR. Five of 14 PR and two of 13 CR were HO+ postrace (P>0.05). Prerace HQ values (PR: 1.49 ±0.6 and CR: 0.60±0.1 mg hemoglobin/g stool) were not significantly different from postrace HQ values (PR:0.73±0.2 and CR:0.86±0.2 mg Hgb/g stool). Despite postrace HO+ conversion, no individual postrace HQ became abnormal. The frequency of gastrointestinal symptoms was similar for CR and PR, as well as HO- and HO+ individuals. Cimetidine did not significantly affect occult gastrointestinal bleeding as measured by HO or HQ results. This suggests that marathon-associated gastrointestinal symptoms and bleeding may be due to lesions other than acid-mediated disease or hemorrhagic gastritis.This work was presented in part at the 1990 Digestive Disease Week Annual Scientific Meeting, American Gastroenterological Association, San Antonio, Texas, May 16, 1990, and published in abstract form in Gastroenterology 98:A91, 1990.Work supported by: US Naval Medical Research and Development Command, Grant NN0007589 WR 00016.The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army, the Department of Defense, or the Uniformed Services University of the Health Sciences.     

Gastrointestinal bleeding in competitive runners

Competitive runners have been shown to develop previously undescribed clinical conditions, including runner's anemia. This has been shown to be an iron-deficiency anemia of several etiologies including gastrointestinal bleeding. Although 8–23% of runners have been shown to have guaiac-positive stools after a marathon, the incidence of significant and prolonged bleeding is unknown. We report four cases of competitive runners with iron-deficiency anemia, gastrointestinal bleeding coinciding with running, and no definitive gastrointestinal pathology despite extensive evaluation.Dr. McMahon is the recipient of a National Fund for Medical Education Postgraduate Fellowship.     

Hematologic and Biochemical Laboratory Parameters Before and After a Marathon Race

Marathon racing is a strenuous exercise that has a profound effect on many laboratory parameters. Participants in marathon races may require abstinence of exercise and the performance of laboratory assays several days after the event. The aim of this study was to evaluate the possible changes in blood cell count and biochemical parameters observed in participants in a marathon 3 days before and 3 days after and before and immediately after a cardiopulmonary exercise test. Incremental cycle ergometry up to maximal capacity was performed in 7 marathon runners, 3 days before and 3 days after the race. The % peak oxygen consumption (peak %VO₂) achieved was statistically significantly lower after than before the race (p = 0.02). No statistically significant differences were observed in cardiac frequency (p = 0.148) or blood cell count (p = 0.501). Also, the concentration of sodium, potassium, calcium, magnesium, lactate dehydrogenase (LDH), phosphocreatine kinase (CPK) and glucose, measured before and immediately after the pulmonary exercise test, did not differ significantly (p < 0.5). A significant percentage of the laboratory results were outside the standard reference rates. According to our data, exercise performance, as expressed by peak %VO₂, continued to be decreased in marathon runners 3 days after the race. The blood cell count and biochemical parameters did not differ significantly but many marathon runners were outside the standard reference rates. Unfortunately, only 7 subjects were available for this study. Further studies with larger samples and with samples obtained at multiple times during and after exercise are needed to clarify the effects of long-distance running.     

Gastrointestinal bleeding during an ultramarathon

Digestive symptoms and gastrointestinal bleeding occur in endurance runners and may contribute to runner's anemia. The cause is unknown, but the frequency of fecal blood loss has been reported to be 8–23% of marathon runners (1–7). Races of longer distances have not been investigated. An ultramarathon is a race that is longer than the 26.2 miles of a marathon and commonly involves distances of 30–100 or more miles and can last 24 hr or more. It differs from the marathon in duration, pace, and intrarace diet. The Old Dominion One Hundred Mile Endurance Run is held in the mountains of Virginia each June. It is open only to experienced ultrarunners who have completed a 50-mile race in less than 9 hr. This race offers a unique opportunity to study highly trained individuals undergoing a tremendous stress to not only their cardiovascular and musculoskeletal systems but also to their gastrointestinal system. The purpose of this prospective study is to determine the incidence of Hemoccult positivity occurring in association with an ultramarathon and evaluating, by means of a questionnaire, cofactors contributing to the gastrointestinal bleeding.The opinions and assertions contained herein are those of the authors and are not to be construed as reflecting the views of Walter Reed Army Medical Center, the Department of the Army or the Department of Defense.     

Echocardiographic assessment of the left ventricle of endurance athletes just before and after exercise

Fourteen normal subjects and 10 marathon runners were studied using postexercise echocardiography to assess left ventricular (LV) wall thickness, afterload and systolic performance. Cuff systolic blood pressures and M-mode echocardiographic recordings were obtained in the supine position before and within 2 minutes of termination of maximal treadmill exercise. Both groups had increased LV dimensional shortening (% fractional shortening) and stroke volume after exercise, although runners had larger increases compared to untrained normal subjects (p less than 0.05). Preload, as estimated by LV end-diastolic dimension, was greater in runners compared to normal subjects at rest (52 vs 48 mm, p less than 0.05). However, preload did not change after exercise in either group. Afterload, estimated by LV end-systolic wall stress, decreased after exercise in both groups; however, runners had lower afterload at rest and immediately after exercise compared to normal subjects (p less than 0.05). The runners' greater LV end-systolic wall thickness appears to account for their lower afterload. Data indicate that marathon runners have lower afterload at rest and greater decrease in afterload after maximal exercise, compared to untrained normal subjects.     

Fitness in the fit: does physical conditioning affect cardiovascular risk factors in middle-aged marathon runners?

OBJECTIVE: The study was designed to assess cardiovascular risk factorsin marathon runners with different degrees of fitness. DESIGN: A total of 30 male middle-aged marathon runners were dividedaccording to their marathon running time into fit (265 ±8 min), fitter (222 ± 5 min) and fittest (178 ±12 min). The three groups of 10 runners each were comparablein age, weight, and body surface area. Cardiovascular risk factorswere assessed by measuring arterial pressure before and duringexercise (150 watts) and determination of plasma lipoproteins,uric acid, glucose and white blood cell count before and aftera marathon run. RESULTS: All measured laboratory values such as high-density lipoproteincholesterol (P<0.05), low-density lipoprotein cholesterol(P <0.05), total cholesterol (non-significant), triglycerides(non-significant), blood sugar (non-significant), uric acid(P <0.05), and white blood cell count (P <0.05) indicateda lower cardiovascular risk in the fastest when compared withthe slowest runners. Resting blood pressure was similar in thethree groups but consistently lower at all levels of exercisein the fittest when compared with the less fit runners. Thefittest runners also showed greater increases in high-densitylipoprotein cholesterol after the marathon run (14% vs 8% inthe slowest runners, P<0.05). CONCLUSIONS: We conclude that even at the extreme end of a continuum suchas represented by well-conditioned, middle-aged marathon runners,cardiovascular risk factors are related to the degree of fitness,as measured by the marathon running time.     

Inspiratory muscle performance in endurance athletes and sedentary subjects

OBJECTIVE: The aim of this study was to determine whether whole-body endurance training is associated with increased respiratory muscle strength and endurance. METHODOLOGY: Respiratory muscle strength (maximum inspiratory pressure (PImax)) and endurance (progressive threshold loading of the inspiratory muscles) were measured in six marathon runners and six sedentary subjects. RESULTS: PImax was similar between the two groups of subjects but the maximum threshold pressure achieved was greater in marathon runners (90 +/- 8 vs 78 +/- 10% of PImax, respectively, mean +/- SD, P < 0.05). During progressive threshold loading, marathon runners breathed with lower frequency, higher tidal volume, and longer inspiratory and expiratory time. At maximum threshold pressure, marathon runners had lower arterial O2 saturation, but perceived effort (Borg scale) was maximal in both groups. Efficiency of the respiratory muscles was similar in both groups being 2.0 +/- 1.7% and 2.3 +/- 1.8% for marathon runners and sedentary subjects, respectively. CONCLUSIONS: The apparent increase in respiratory muscle endurance of athletes was a consequence of a difference in the breathing pattern adopted during loaded breathing rather than respiratory muscle strength or efficiency. This implies that sensory rather than respiratory muscle conditioning may be an important mechanism by which whole-body endurance is increased.     

Diagnostic value of a guaiac occult blood test and faecal alpha 1-antitrypsin.

This study evaluates the diagnostic accuracy of a faecal occult blood test and faecal alpha 1-antitrypsin in the investigation of patients with gastrointestinal symptoms or iron deficiency anaemia. One hundred and seventy nine patients with either iron deficiency anaemia (n = 67), changed bowel habit and aged > 39 years (n = 107), or a history suggestive of melaena (n = 5) provided faecal samples. After investigation, 32 patients had a diagnosis of possible gastrointestinal bleeding and 139 patients had no evidence of gastrointestinal bleeding. Eight patients had a cause of enteric protein loss in the absence of gastrointestinal bleeding and were excluded from subsequent analysis. The faecal alpha 1-antitrypsin test was diagnostically more accurate than the guaiac test in identifying probable gastrointestinal bleeding (82% and 72% respectively, p < 0.05). This faecal alpha 1-antitrypsin test was also more specific (83% and 72% respectively, p < 0.05), but was not significantly more sensitive (78% and 72% respectively). The sensitivity of these tests was insufficient to recommend their use for most patients in this study.     

Transient Myocardial Tissue and Function Changes During a Marathon in Less Fit Marathon Runners

Background

Although regular physical activity improves health, strenuous exercise might transiently increase cardiac risk. Training and fitness might provide protection.

Methods

We prospectively studied 20 recreational marathon runners without known cardiovascular disease or symptoms: at peak training before, immediately after, and 3 months after a 42.2-km marathon. Changes in global/segmental myocardial function, edema, resting perfusion, and fibrosis were measured.

Results

At peak training, runners exercised 8.1 ± 2.3 hours and 62 ± 18 km per week with mean maximal oxygen consumption (VO₂max) of 53.2 ± 8.3 mL/kg/min. In response to the marathon, global left ventricular and right ventricular ejection fraction decreased in half of the runners; these runners had poorer peak training distance, training time, and fitness level. Change in global left ventricular ejection fraction was associated with VO₂max. Overall, 36% of segments developed edema, 53% decreased function, and 59% decreased perfusion. Significant agreement was observed between segment decreasing function, decreasing perfusion, and developing edema. Myocardial changes were reversible at 3 months.

Conclusions

Completing a marathon leads to localized myocardial edema, diminished perfusion, and decreased function occurring more extensively in less trained and fit runners. Although reversible, these changes might contribute to the transient increase in cardiac risk reported during sustained vigorous exercise.     

Early predictors of severe lower gastrointestinal bleeding and adverse outcomes: a prospective study.

BACKGROUND & AIMS: Unlike in upper tract bleeding, prognostic factors for ongoing or recurrent bleeding from the lower gastrointestinal tract have not been well-defined. The aim of this study was to identify risk factors for severe lower gastrointestinal bleeding and for significant adverse outcomes. METHODS: All patients seeking attention at a university emergency department for gastrointestinal bleeding were prospectively identified during a 3-year period. Ninety-four of 448 (21%) admitted patients had lower gastrointestinal bleeding. Clinical predictors available in the first hour of evaluation were recorded. The primary outcome, severe lower gastrointestinal bleeding, was defined as gross blood per rectum after leaving the emergency department associated with either abnormal vital signs (systolic blood pressure < 100 mm Hg or heart rate > 100/min) or more than a 2-unit blood transfusion during the hospitalization. Significant adverse outcomes, including death, were tabulated. RESULTS: Thirty-seven patients (39%) had severe lower gastrointestinal bleeding. Independent risk factors for severe lower gastrointestinal bleeding were initial hematocrit 100/min) 1 hour after initial medical evaluation (OR, 4.3; 95% CI, 1.4-12.5); and gross blood on initial rectal examination (OR, 3.9; 95% CI, 1.2-13.2). Nineteen patients (20%) experienced a significant adverse outcome, including 3 deaths. The main independent predictor of adverse outcomes was severe lower gastrointestinal bleeding (OR, 5.3; 95% CI, 1.7-16.5). CONCLUSIONS: Risk factors are available in the first hour of evaluation in the emergency department to identify patients at risk for severe lower gastrointestinal bleeding. Severe lower gastrointestinal bleeding is a significant risk factor for global adverse outcomes.     

Coronary atherosclerosis burden, but not transient troponin elevation, predicts long-term outcome in recreational marathon runners

We determined the prognostic value of transient increases in high-sensitive serum troponin I (hsTnI) during a marathon and its association with traditional cardiovascular risk factors and imaging-based risk markers for incident coronary events and all-cause mortality in recreational marathon runners. Baseline data of 108 marathon runners, 864 age-matched controls and 216 age- and risk factor-matched controls from the general population were recorded and their coronary event rates and all-cause mortality after 6 ± 1 years determined. hsTnI was measured in 74 marathon finishers before and after the race. Other potential predictors for coronary events, i.e., Framingham Risk Score (FRS), coronary artery calcium (CAC) and presence of myocardial fibrosis as measured by magnetic resonance imaging-based late gadolinium enhancement (LGE), were also assessed. An increase beyond the 99 % hsTnI-threshold, i.e., 0.04 μg/L, was observed in 36.5 % of runners. FRS, CAC, or prevalent LGE did not predict hsTnI values above or increases in hsTnI beyond the median after the race, nor did they predict future events. However, runners with versus without LGE had higher hsTnI values after the race (median (Q1/Q3), 0.08 μg/L (0.04/0.09) versus 0.03 μg/L (0.02/0.06), p = 0.039), and higher increases in hsTnI values during the race (median (Q1/Q3), 0.05 μg/L (0.03/0.08) versus 0.02 μg/L (0.01/0.05), p = 0.0496). Runners had a similar cumulative event rate as age-matched or age- and risk factor-matched controls, i.e., 6.5 versus 5.0 % or 4.6 %, respectively. Event rates in runners with CAC scores <100, 100–399, and ≥400 were 1.5, 12.0, and 21.4 % (p = 0.002 for trend) and not different from either control group. Runners with coronary events had a higher prevalence of LGE than runners without events (57 versus 8 %, p = 0.003). All-cause mortality was similar in marathon runners (3/108, 2.8 %) and controls (26/864, 3.0 % or 5/216, 2.4 %, respectively). Recreational marathon runners with prevalent myocardial fibrosis develop higher hsTnI values during the race than those without. Increasing coronary artery calcium scores and prevalent myocardial fibrosis, but not increases in hsTnI are associated with higher coronary event rates. All-cause mortality in marathon runners is similar to that in risk factor-matched controls.     

Allergy in marathon runners and effect of Lactobacillus GG supplementation on allergic inflammatory markers

OBJECTIVE: We studied the prevalence of asthma and allergy in non-elite marathon runners and investigated the effects of probiotic supplementation on allergic inflammatory markers. METHODS: Asthma and allergies were surveyed by questionnaire, and blood eosinophils, serum eosinophil cationic protein (ECP), total IgE, and Phadiatop were measured in 141 Finnish marathon runners who took part in the Helsinki City Marathon. They were also randomized to receive either Lactobacillus GG (LGG) or placebo during the 3 months of the pollen season prior to the marathon. RESULTS: Lifetime prevalence of physician-diagnosed asthma was 4.3% (six out of 139 athletes), of allergic rhinitis 17.3% (24/139), of food allergy 5.0% (7/139), and of atopic eczema 4.3% (6/139). Prevalence of atopy was 31% (35/112), and 21% (24/112) of the athletes were sensitized to birch pollen. Asthma or allergy medication was used by 20% (28/139) of the athletes. During pollen season, serum ECP increased significantly in all athletes, and total IgE and Phadiatop in atopics. The marathon induced a significant eosinopenia but had no effect on serum ECP or total IgE. No differences in changes were seen between groups receiving LGG or placebo. CONCLUSION: Non-elite marathon runners have asthma and allergies similar to Finnish general population. LGG supplementation did not prevent the increase of allergic markers during the pollen season, or the eosinopenia induced by the marathon.     

Optimal assessment of gastrointestinal side effects induced by non-steroidal anti-inflammatory drugs. Endoscopic lesions, faecal blood loss, and symptoms not necessarily correlated, as observed after naproxen and oxindanac in healthy volunteers

Gastrointestinal side effects caused by naproxen and oxindanac (a developmental non-steroidal anti-inflammatory drug) were compared by combined endoscopy and determination of faecal blood loss in 16 healthy male volunteers in a randomized, double-blind, crossover study. Individual daily faecal blood loss was determined by means of 51Cr-labelled erythrocytes. Gastroduodenoscopy was performed before and after administration of naproxen, 750 mg/day, and oxindanac, 600 mg/day, for 1 week each. A washout period of at least 3 weeks was inserted between drug periods. Visual analogue scales (VAS) were used for endoscopic assessment of lesions and subjective complaints. Mean faecal blood loss increased from a base line 0.48 ml/24 h to 1.59 ml/24 h with naproxen (p less than 0.01) and from 0.56 ml/24 h to 1.31 ml/24 h with oxindanac (p less than 0.01). VAS scores for gastroduodenal lesions increased significantly with both drugs. Naproxen caused a significantly greater increase than oxindanac (p less than 0.05). There was no correlation between gastrointestinal blood loss and endoscopic findings. Subjective symptoms were correlated to faecal blood loss with naproxen, but not to endoscopic findings. No such correlations were observed for oxindanac. Naproxen caused a significant prolongation of bleeding time (p less than 0.01), whereas the increase caused by oxindanac was not significant (p = 0.09).     

Long-term cardiac remodeling and arrhythmias in nonelite marathon runners

Long-term endurance sports are associated with atrial remodeling and atrial arrhythmias. More importantly, high-level endurance training may promote right ventricular (RV) dysfunction and complex ventricular arrhythmias. We investigated the long-term consequences of marathon running on cardiac remodeling as a potential substrate for arrhythmias with a focus on the right heart. We invited runners of the 2010 Grand Prix of Bern, a 10-mile race. Of 873 marathon and nonmarathon runners who applied, 122 (61 women) entered the final analysis. Subjects were stratified according to former marathon participations: control group (nonmarathon runners, n = 34), group 1 (1 marathon to 5 marathons, mean 2.7, n = 46), and group 2 (≥6 marathons, mean 12.8, n = 42). Mean age was 42 ± 7 years. Results were adjusted for gender, age, and lifetime training hours. Right and left atrial sizes increased with marathon participations. In group 2, right and left atrial enlargements were present in 60% and 74% of athletes, respectively. RV and left ventricular (LV) dimensions showed no differences among groups, and RV or LV dilatation was present in only 2.4% or 4.3% of marathon runners, respectively. In multiple linear regression analysis, marathon participation was an independent predictor of right and left atrial sizes but had no effect on RV and LV dimensions and function. Atrial and ventricular ectopic complexes during 24-hour Holter monitoring were low and equally distributed among groups. In conclusion, in nonelite athletes, marathon running was not associated with RV enlargement, dysfunction, or ventricular ectopy. Marathon running promoted biatrial remodeling.     

Changes in the Gastrointestinal Mucosa after Long-Distance Running

Two groups of long-distance runners were investigated for the effect of marathon running on the gastrointestinal mucosa. In one group gastric erosions with bleeding were found in five of nine subjects, mostly localized to the corpus region. The relative gastric blood flow measured by endoscopic laser Doppler flowmetry was slightly decreased in the cardia region (from 7.0 to 5.8; p < 0.05) but unchanged in the other parts of the stomach, including the erosive lesions. In another group (n = 8) all the subjects showed a substantial increase in the urinary excretion of ⁵¹Cr-labeled ethylenediaminetetraacetic acid after oral intake, which indicates an increase in the intestinal permeability. There is reason to suggest that long-distance running affects the integrity of the gastric and the intestinal mucosa.     

Association between prolonged bleeding time and gastrointestinal hemorrhage in 102 patients with liver cirrhosis: results of a retrospective study

BACKGROUND: Gastrointestinal bleeding is a frequent complication of liver cirrhosis (LC) and represents an important warning sign of imminent death. Platelet dysfunction is an abnormality occurring prevalently in severe liver failure, and could well predispose to bleeding. METHODS: One hundred and two patients with liver cirrhosis diagnosed by needle liver biopsy were studied. According to the Child-Pugh classification, 23 were A class, 42 B class and 37 C class cases. Prothrombin activity, aPTT, fibrinogen, FDPs, XDP and platelet count were measured in each patient; bleeding time was measured in all but 17 of them. Forty (39%) had experienced gastrointestinal bleeding during the last 3 years (2 A class, 12 B class, 26 C class). RESULTS: Patients with a history of previous gastrointestinal bleeding showed lower values for prothrombin activity and fibrinogen, and higher percentage of elevated FDP and XDP levels; moreover, they presented lower platelet counts and more prolonged bleeding times than patients without gastrointestinal blood loss. CONCLUSIONS: While our findings confirm the relationship between hyperfibrinolysis and bleeding, the association between bleeding time prolongation and gastrointestinal blood loss suggests studying platelet function prospectively in LC in order to analyze its role, if any, in favoring hemorrhage activity.     

Stomatocytic transformation of red blood cells after marathon running

We studied red blood cell morphology in two marathon runners before, immediately after, and 1 day after a marathon race. A discocyte-stomatocyte transformation was found by light microscopy of wet preparations and also by scanning electron microscopy, with about one-half the erythrocytes becoming cup-shaped after the marathon. These changes were completely reversible within 18 hr after the race.     

Gastrointestinal bleeding and protein-losing enteropathy after the fontan operation

Gastrointestinal bleeding has not been reported in patients with protein-losing enteropathy. The investigators describe 3 patients with protein-losing enteropathy and gastrointestinal bleeding after Fontan operations. Bleeding occurred at the onset of protein-losing enteropathy, was macroscopic, led to anemia, and required blood transfusion in all patients. Invasive testing failed to demonstrate gastrointestinal pathology as a source of bleeding. In conclusion, unexplained gastrointestinal bleeding may be part of the clinical spectrum of protein-losing enteropathy.