Breath hydrogen in pneumatosis cystoides intestinalis

Intussusception associated with pneumatosis cystoides intestinalis in a male adolescent: A case report

Pneumatosis cystoides intestinalis is an uncommon disease that rarely causes intussusception. We report the case of a 16-year-old male patient with intermittent abdominal pain who was diagnosed with intussusception. The patient had no history of raw food ingestion, fever, diarrhea, or hematochezia. Computed tomography revealed intussusception characterized by a crab-finger appearance, and pneumatosis cystoides intestinalis was diagnosed by colonoscopy. Treatment with hyperbaric enema and low-flow oxygen therapy resulted in a prominent improvement of the lesion. No recurrence was observed for > 1 year. Intermittent abdominal pain without diarrhea or hematochezia in male adolescents may represent pneumatosis cystoid-related intussusception, and the addition of low-flow oxygen therapy may help avoid surgery.

Portal vein gas combined with pneumatosis intestinalis and emphysematous cystitis: A case report and literature review

BACKGROUND

Portal venous gas (PVG) is a rare clinical condition usually indicative of severe disorders, including necrotizing enterocolitis, bowel ischemia, or bowel wall rupture/infarction. Pneumatosis intestinalis (PI) is a rare illness characterized by an infiltration of gas into the intestinal wall. Emphysematous cystitis (EC) is relatively rare and characterized by intramural and/or intraluminal bladder gas best depicted by cross-sectional imaging. Our study reports a rare case coexistence of PVG presenting with PI and EC.

CASE SUMMARY

An 86-year-old woman was admitted to the emergency room due to the progressive aggravation of pain because of abdominal fullness and distention, complicated with vomiting and stopping defecation for 4 d. The abdominal computed tomography (CT) plain scan indicated intestinal obstruction with ischemia changes, gas in the portal vein, left renal artery, superior mesenteric artery, superior mesenteric vein, some branch vessels, and bladder pneumatosis with air-fluid levels. Emergency surgery was conducted on the patient. Ischemic necrosis was found in the small intestine approximately 110 cm below the Treitz ligament and in the ileocecal junction and ascending colon canals. This included excision of the necrotic small intestine and right colon, fistulation of the proximal small intestine, and distal closure of the transverse colon. Subsequently, the patient displayed postoperative short bowel syndrome but had a good recovery. She received intravenous fluid infusion and enteral nutrition maintenance every other day after discharge from the community hospital.

CONCLUSION

Emergency surgery should be performed when CT shows signs of PVG with PI and EC along with a clinical situation strongly suggestive of bowel ischemia.

Benign Pneumatosis Intestinalis: A Case Report and Review of the Literature

BACKGROUND

Pneumatosis intestinalis is the presence of gas within the walls of the intestine on imaging and has variable clinical significance, ranging from an incidental finding to a harbinger of intra-abdominal catastrophe. There are multiple mechanisms by which this radiographic finding develops, including bacterial gas production, increased intraluminal pressure within the gastrointestinal tract, mechanical disruption of the gut mucosa, and tracking of pulmonary gas along the mesenteric vasculature.

CASE PRESENTATION

We present the case of a 61-year-old male veteran who had sustained a remote anoxic brain injury resulting in chronic dependence on a gastrostomy tube for enteral nutrition, found incidentally to have pneumatosis intestinalis without signs of intra-abdominal catastrophe.

CONCLUSIONS

Appropriate interpretation of this finding can lead to life-saving interventions and avoid unnecessary surgical procedures.

Intestinal pneumatosis: differential diagnosis

Intestinal pneumatosis (IP) is an infrequent radiological sign defined as pathological gas infiltration into the bowel wall. It may be associated to different underlying clinical conditions-inflammatory bowel diseases, malignancies, chemotherapy, infections, immune deficiency status, trauma, intestinal ischemia, and necrosis-that are often related to emergency state and require a prompt diagnosis. All the imaging techniques, especially abdominal radiography and Computed Tomography, could detect the presence of IP and discern the forms related to emergency conditions. The differential diagnosis is essential to start an immediate clinical or surgical management and treatment. The aim of this article is to review the radiological features of IP in different illnesses, with particular attention to differential diagnosis.

Pneumatosis cystoides intestinalis: A case report

RATIONALE

Pneumatosis cystoides intestinalis (PCI) is a rare condition characterized by multiple gas-filled cysts in the intestinal wall, and can be caused by many conditions.

PATIENT CONCERNS

We reported a-69-year-old man with a long history of chronic obstructive pulmonary disease was admitted to the gastroenterology department because of alternating bowel movement and intermittent bloody stool.

DIAGNOSES

Colonoscopy revealed multiple nodular protuberances covered with normal-looking mucosa in the ascending and proximal transverse colon. Abdominal computed tomography scan and endoscopic ultrasound revealed multiple gas-filled cystic lesions in the submucosa. The diagnosis of PCI was confirmed by cyst collapse after puncturing with a fine needle.

INTERVENTIONS AND OUTCOMES

Considering that the patient had no peritonitis or other complications, conservative approaches, including oxygen inhalation and oral probiotics, were used. The patient was transferred to the anorectal department after 5days of clinical observation in good condition to further treat hemorrhoids.

LESSONS

PCI is a rare condition that may be secondary to many other diseases. Because of its atypical clinical manifestations, it can be misdiagnosed as other diseases, such as polyps, inflammatory bowel disease, and even cancer. The diagnosis of PCI depends on computed tomography, colonoscopy, and endoscopic ultrasonography. Fine-needle aspiration may be helpful in the diagnosis and treatment of PCI.

PaO2-guided Low-dose Oxygen Therapy for Pneumatosis Cystoides Intestinalis to Prevent Acute Exacerbation of Interstitial Pneumonia

We herein report the first case of low-dose oxygen therapy for pneumatosis cystoides intestinalis (PCI) using PaO₂ as a therapeutic index to prevent acute exacerbation of interstitial pneumonia. An 86-year-old man was admitted to our hospital with abdominal distension. PCI was diagnosed by abdominal computed tomography. Low-dose oxygen therapy was started to avoid acute exacerbation of interstitial pneumonia. The oxygen dose was adjusted so that the PaO₂ value was approximately 100 mmHg. After seven days of treatment, the colon gas had disappeared, and no acute exacerbation of interstitial pneumonia was observed. A PaO₂ value around 100 mmHg is effective for PCI without inducing acute exacerbation of interstitial pneumonia.

Idiopathic pneumatosis intestinalis secondary to lactulose use in patients with cirrhosis

BACKGROUND AND AIM

Few case reports exist that link lactulose use with pneumatosis intestinalis in cirrhotics. This study investigates the relationship between lactulose use and idiopathic pneumatosis intestinalis in a cohort of cirrhotic patients.

METHODS

This case series considers several notable cases of patients with idiopathic pneumatosis intestinalis and concurrent lactulose use. Idiopathic pneumatosis intestinalis was defined as pneumatosis intestinalis with no identifiable etiology. A cohort of 119 patients with cirrhosis and pneumatosis intestinalis were identified in a tertiary care setting, via chart review by a multidisciplinary team. Eleven of these patients were found to have idiopathic pneumatosis intestinalis. Nine of these patients were being treated with lactulose.

RESULTS

Six out of 9 patients with idiopathic pneumatosis intestinalis that were being treated with lactulose saw resolution of pneumatosis intestinalis following discontinuation of treatment.

CONCLUSIONS

The etiology of idiopathic pneumatosis intestinalis is likely multifactorial, but lactulose might play a preventable role in its formation.

Idiopathic Pneumatosis of Small Bowel and Bladder

An 81-year-old woman presented with multiple episodes of loose bowel movements. CT scan of the abdomen and pelvis revealed pneumatosis cystoides intestinalis and asymptomatic emphysematous cystitis. The patient had an extensive workup with no obvious identified pathology to explain diffuse pneumatosis of the small bowel and bladder. Her symptoms improved with symptomatic management, empirical antibiotics, and no surgical intervention.

Pneumatosis cystoides intestinalis: a case report and literature review

BACKGROUND

Pneumatosis cystoides intestinalis (PCI) is a low-incidence disease that confuses many doctors. A vast number of factors are suspected to contribute to its pathogenesis, such as Crohn's disease, intestinal stenosis, ulcerative colitis, drug use, extra-gastrointestinal diseases, and chronic obstructive pulmonary disease. Most consider its pathogenesis interrelated to an increase in intra-intestinal pressure and the accumulation of gas produced by aerogenic bacteria, and patients with atypical symptoms and imaging manifestations tend to be misdiagnosed.

CASE PRESENTATION

A 64-year-old man complained of a 3-month history of bloody stool without mucopurulent discharge, abdominal pain, or diarrhea. Colonoscopy revealed multiple nodular projections into the segmental mucosa of the sigmoid colon. Crohn's disease and malignant disease ware suspected first according to the patient's history, but laboratory examinations did not confirm either. Endoscopic ultrasound (EUS) revealed multiple cystic lesions in the submucosa. Moreover, computer tomography scan showed multiple bubble-like cysts. Combined with ultrasonography, computed tomography, and pathology findings, we ultimately made a diagnosis of PCI. Instead of surgery, we recommended conservative treatment consisting of endoscopy and oral drug administration. His symptoms improved with drug therapy after discharge, and no recurrence was noted on follow-up.

CONCLUSIONS

The incidence of PCI is low. Due to a lack of specificity in clinical manifestations and endoscopic findings, it often misdiagnosed as intestinal polyps, tumors, inflammatory bowel disease, or other conditions. Colonoscopy, computed tomography, and ultrasonography have demonstrated benefit in patients with multiple nodular projections in colon. Compared to the treatment of the above diseases, PCI treatment is effective and convenient, and the prognosis is optimistic. Therefore, clinicians should increase their awareness of PCI to avoid unnecessary misdiagnosis.

Pneumatosis cystoides intestinalis: a case report and literature review

Background

Pneumatosis cystoides intestinalis (PCI) is a low-incidence disease that confuses many doctors. A vast number of factors are suspected to contribute to its pathogenesis, such as Crohn’s disease, intestinal stenosis, ulcerative colitis, drug use, extra-gastrointestinal diseases, and chronic obstructive pulmonary disease. Most consider its pathogenesis interrelated to an increase in intra-intestinal pressure and the accumulation of gas produced by aerogenic bacteria, and patients with atypical symptoms and imaging manifestations tend to be misdiagnosed.

Case presentation

A 64-year-old man complained of a 3-month history of bloody stool without mucopurulent discharge, abdominal pain, or diarrhea. Colonoscopy revealed multiple nodular projections into the segmental mucosa of the sigmoid colon. Crohn’s disease and malignant disease ware suspected first according to the patient’s history, but laboratory examinations did not confirm either. Endoscopic ultrasound (EUS) revealed multiple cystic lesions in the submucosa. Moreover, computer tomography scan showed multiple bubble-like cysts. Combined with ultrasonography, computed tomography, and pathology findings, we ultimately made a diagnosis of PCI. Instead of surgery, we recommended conservative treatment consisting of endoscopy and oral drug administration. His symptoms improved with drug therapy after discharge, and no recurrence was noted on follow-up.

Conclusions

The incidence of PCI is low. Due to a lack of specificity in clinical manifestations and endoscopic findings, it often misdiagnosed as intestinal polyps, tumors, inflammatory bowel disease, or other conditions. Colonoscopy, computed tomography, and ultrasonography have demonstrated benefit in patients with multiple nodular projections in colon. Compared to the treatment of the above diseases, PCI treatment is effective and convenient, and the prognosis is optimistic. Therefore, clinicians should increase their awareness of PCI to avoid unnecessary misdiagnosis.

Gastric Outlet Obstruction and Sigmoid Volvulus in a Patient with Pneumatosis intestinalis: An Etiology or a Complication

Pneumatosis intestinalis (PI) is a radiographic finding which refers to the presence of gas within the wall of any part of the gastrointestinal tract. While in some cases it is an incidental finding which usually represent its benign nonischemic etiology, it may indicate a catastrophic intra-abdominal condition and distinctly characteristic of ischemic enterocolitis. Herein, we discuss the clinical signs and symptoms, the radiological features, the surgical management and outcome of an extremely rare concurrent triad of PI, gastric outlet obstruction, and the sigmoid volvulus based on a case of a patient who underwent surgery in our hospital, which, we think, can emphasize the mysterious concept of PI's mechanical etiology.

Prolonged postoperative ileus in a patient with primary pneumatosis cystoides intestinalis: a case report

Background

Pneumatosis cystoides intestinalis (PCI) is a rare disease characterized by multiple gas-filled cysts in the intestinal wall and is associated with various comorbidities. We report herein a case of intractable paralytic ileus caused by primary PCI.

Case presentation

A 73-year-old man visited out hospital complaining of abdominal pain and vomiting. He had been hospitalized twice for intestinal obstruction in the past 2 months. Based on his history of appendectomy, mechanical bowel obstruction caused by adhesion was diagnosed, and the patient underwent surgery. However, laparotomy revealed small bowel dilatation despite the absence of obstruction or stenosis. Multiple nodules were found in the wall of the dilated bowel loops. The dilated jejunum was excised. Histological examination revealed that the nodules were small gas-filled cysts, suggesting PCI. We made a diagnosis of ileus with underlying PCI and managed the patient conservatively. A large amount of nasogastric tube drainage continued for a long period postoperatively. The patient underwent relaparotomy 35 days after the first operation. The upper jejunum was markedly dilated, although no mechanical stenosis was found. The atonic, dilated jejunum was excised and the ileal stump was anastomosed to the duodenum in a double tract fashion. The patient underwent hyperbaric oxygen therapy because the ileus persisted postoperatively. His condition gradually improved and he was discharged 53 days after the second operation.

Conclusions

Non-operative treatment is recommended for primary PCI of unknown etiology. Surgeons should be mindful of the possibility of primary PCI when considering surgical intervention for patients with bowel obstruction.

Pneumatosis intestinalis presenting as pneumoperitoneum in a teenage girl with pyloric stenosis

A 16-year-old girl presented with free gas under the diaphragm after endoscopic balloon dilation for pyloric stenosis. There was no perforation site identified on laparotomy. However, there was massive pneumatosis intestinalis involving the entire small bowel.

Pneumatosis cystoides intestinalis: a rare benign cause of pneumoperitoneum

Pneumatosis cystoides intestinalis is a rare gastrointestinal complication in the course of connective tissue diseases, especially in scleroderma, that can lead to pneumoperitoneum or obstruction. Findings on plain radiography may reveal radiolucent linear or bubbly circular air bubbles in the bowel wall, with or without free gas accumulation in the peritoneal cavity. Treatment of pneumatosis cystoides intestinalis ranges from supportive care to laparotomy.

Pneumatosis cystoides intestinalis

Pneumatosis cystoides intestinalis (PCI) is a rare condition that may be associated with a variety of diseases. The presenting clinical picture may be very heterogeneous and represent a challenge for the clinician. In the present paper we describe both a common and an uncommon clinical presentation of PCI and review the pertaining literature. Our cases confirm that, apart from asymptomatic cases, the clinical presentation of PCI may be widely different and suggest that a new onset of stipsis might be the presenting symptom. Diagnosis might be suggested by a simple X-ray of the digestive tract showing a change in the characteristics of the intestinal wall in two-thirds of these patients. However, one third of the patients do not have a suggestive X-ray and require a computed tomography (CT) scan/nuclear magnetic resonance that may reveal a thickened bowel wall containing gas to confirm the diagnosis and distinguish PCI from intraluminal air or submucosal fat. CT also allows the detection of additional findings that may suggest an underlying, potentially worrisome cause of PCI such as bowel wall thickening, altered contrast mucosal enhancement, dilated bowel, soft tissue stranding, ascites and the presence of portal air. Our results also point out that clinicians and endoscopists should be aware of the possible presentations of PCI in order to correctly manage the patients affected with this disease and avoid unnecessary surgeries. The increasing number of colonoscopies performed for colon cancer screening makes PCI more frequently casually encountered and/or provoked, therefore the possible endoscopic appearances of this disease should be well known by endoscopists.

Pneumatosis cystoides intestinalis of the ascending colon related to acarbose treatment: a case report

Introduction

Pneumatosis cystoides intestinalis is characterized by the presence of multiple gas-filled cysts in the intestinal wall, the submucosa and/or subserosa of the intestine. The term pneumatosis cystoides coli is synonymous with pneumatosis cystoides intestinalis when the disorder is limited to the colon. It is a secondary finding caused by a wide variety of underlying gastrointestinal or extragastrointestinal diseases but rarely occurs in the course of treatment with an α-glucosidase inhibitor. This is the first report of pneumatosis cystoides intestinalis after 12 years of treatment with the α-glucosidase inhibitor acarbose.

Case presentation

A 65-year-old Caucasian German woman was referred to our hospital for hemicolectomy. She had been treated for type 2 diabetes mellitus with an α-glucosidase inhibitor (acarbose, 150 mg daily) for 12 years. Three months before referral, she had complained of left abdominal pain. 'Polyposis coli' in the ascending colon and diverticulosis were diagnosed. Colonoscopy and computed tomography scans of the abdomen were repeated and revealed pneumatosis cystoides coli located in the ascending colon, whereas diverticulosis of the sigmoid colon was confirmed. Histological examination of a biopsy specimen only showed colon mucosa. After discontinuing administration of the α-glucosidase inhibitor for 3 months and on repeated colonoscopy, the polypoid lesions had completely disappeared.

Conclusion

This case illustrates that pneumatosis cystoides coli can be a source of diagnostic confusion. Pneumatosis cystoides coli must be considered in the initial differential diagnosis of patients especially in the presence of multiple colonic polypoid lesions. It is important to take pneumatosis cystoides intestinalis into consideration when prescribing α-glucosidase inhibitors to patients with diabetes who have diabetic autonomic neuropathy with decreased intestinal motility, or to patients taking steroids.

Influence of previously ingested wheat on fasting breath hydrogen in celiac patients

The excretion of hydrogen in breath commonly persists, despite an overnight fast. Although the elevation of hydrogen concentration above the fasting value after the administration of a test sugar is evidence of malabsorption, the level of the fasting value itself in untreated celiac patients is unknown. Therefore, we studied the fasting breath hydrogen (FBH(2)) concentration in 40 healthy controls, 35 subjects with functional bowel disorders, and 30 patients of untreated celiac disease with and without bread or wheat diet one day before the test. The fasting level of hydrogen concentration in untreated celiac patients (28.7 +/- 19.5 ppm) was significantly higher than those in healthy volunteers (9.5 +/- 3.4 ppm) and subjects with functional bowel disorders (10.6 +/- 4.5 ppm). The percentage of patients with elevated H(2) fasting levels in untreated celiac disease (82.5%) was significantly higher than that in healthy controls (10%) and subjects with functional bowel disorders (17.1%). In 30 celiac patients, studied with and without wheat-free diet one day before the test, the fasting hydrogen levels decreased from 28.7 +/- 19.5 ppm to 10.6 +/- 3.5 ppm, and becoming normal in all patients of celiac disease. Our results show that the patients of untreated celiac disease should be instructed not to eat things made up of wheat one day before hydrogen breath testing so that the normal fasting hydrogen concentration can be obtained and false-negative hydrogen breath test results can be avoided.

Pneumatosis coli in a dog

A 17-year-old, castrated male Maltese was presented with chronic polyphagia and a 2-week history of tenesmus, diarrhea, hematochezia, weight loss, and ribbon-like feces. Pneumatosis coli was diagnosed by abdominal radiography. Concurrent hyperadrenocorticism was suspected. The clinical signs of colorectal disease resolved within 2 days of initiating a lowresidue diet and oral metronidazole. Pneumatosis coli should be considered as a differential diagnosis for colorectal disease in dogs.

Pneumatosis intestinalis in adults: management, surgical indications, and risk factors for mortality

BACKGROUND

Pneumatosis intestinalis (PI) is an unusual finding that can exist in a benign setting but can indicate ischemic bowel and the need for surgical intervention. We present a series of cases of PI in adults to illustrate factors associated with death and surgical intervention.

METHODS

We reviewed the radiology database of the Mount Sinai Medical Center for cases of PI between 1996-2006 in adult patients. Chi-square and multivariable logistic regression analyses were used to identify factors significant for surgery and death.

RESULTS

Forty patients developed PI over a 10-year span. The overall in-hospital mortality rate was 20%, and the surgical rate was 35%. Factors independently associated with surgical management on multivariable analysis were age >or= 60 years (p = 0.03), the presence of emesis (p = 0.01), and a WBC > 12 c/mm3 (p = 0.03). Pre-existing sepsis was independently associated with mortality (p = 0.03) while controlling for surgery.

CONCLUSION

Patients with the concomitant presence of PI, a WBC > 12 c/mm3, and/or emesis in the >60-year-old age group were most likely to have surgical intervention, whereas PI patients with sepsis had the highest risk for death. A management algorithm is proposed, but further research will be needed to determine which patients with PI may benefit most from surgery.

Pneumatosis cystoides intestinalis in a patient with dermatomyositis

Images

Pneumatosis intestinalis and portal vein gas after blunt abdominal trauma

The authors report on a 2-year-old boy in whom pneumatosis intestinalis (PI) and portal vein gas (PVG) resulted from blunt abdominal trauma after child abuse. The presumed pathophysiology of PI and PVG is mechanical in this setting. Its presence establishes mucosal injury but does not necessarily imply intestinal necrosis.

Alkyl halides, super hydrogen production and the pathogenesis of pneumatosis cystoides coli

BACKGROUND AND AIMS

The colons of patients with pneumatosis cystoides coli produce excessive H2. Exposure to alkyl halides could explain this. Six consecutive patients who had pneumatosis cystoides coli while taking chloral hydrate (1-5+ g/day) are reported. Patients 2 and 3 were investigated after they had ceased chloral hydrate treatment. One produced methane, the other did not. (Pneumatosis cystoides coli patients are non-methanogenic according to the literature.) Both had overnight fasting breath H2 of less than 10 ppm. A literature review disclosed just one patient who was using chloral at the time of diagnosed pneumatosis cystoides coli, but an epidemic of the disease in workers exposed to trichloroethylene.

METHODS

(i) In vitro experiments with human faeces: chloral or closely related alkyl halides were added to anaerobic faecal cultures derived from four methane-producing and three non-methanogenic human subjects. H2 and CH4 gases were measured. (ii) In vivo animal experiment: chloral hydrate was added to drinking water of four Wistar rats, and faecal H2 compared with control rats.

RESULTS

Alkyl halides increased H2 up to 900 times in methanogenic and 10 times in non-methanogenic faecal cultures. The Ki of chloral was 0.2 mM. Methanogenesis was inhibited in concert with the increase in net H2. In the rat experiment, chloral hydrate increased H2 10 times, but did not cause pneumatosis.

CONCLUSIONS

Chloral and trichloroethylene are alkyl halides chemically similar to chloroform, a potent inhibitor of H2 consumption by methanogens and acetogens. These bacteria are the most important H2-consuming species in the colon. It is postulated that exposure to these alkyl halides increases net H2 production, which sets the scene for "counterperfusion supersaturation" and the formation of gas cysts. In recent times, very low prescribing rates for chloral have caused primary pneumatosis cystoides to become extremely rare. As with primary pneumatosis, secondary pneumatosis cystoides, which occurs if there is small bowel bacterial overgrowth distal to a proximally located gut obstruction, is predicted by counterperfusion supersaturation. "Inherent unsaturation" due to metabolism of O2 is a safety factor, which could explain why gas bubbles do not form more often in tissue with high H2 tension.

Computed tomography in pneumatosis intestinalis: differential diagnosis and therapeutic consequences

Case reports of five patients with pneumatosis intestinalis diagnosed by computed tomography (CT) are presented. Etiology, differential diagnoses, and clinical consequences arising from CT imaging are discussed. In four of the patients, pneumatosis was found to be secondary to gastric ulcer, colon carcinoma, metastasis in the mesentery, and trauma-induced mesenteric ischemia. In one patient, the etiology remained elusive. Using CT, both the extent and the distribution pattern of pneumatosis could be depicted, allowing for differentiation of primary and secondary forms and assessment of prognosis. Evaluation with a lung window is a pre-requisite for reliable diagnosis of pneumatosis with CT. The presence of gas in the mesenteric or portal venous system in mesenteric ischemia is indicative of an unfavorable prognosis.

Does counterperfusion supersaturation cause gas cysts in pneumatosis cystoides coli, and can breathing heliox reduce them?

The pathogenesis of pneumatosis cystoides coli remains obscure in the absence of an explanation for why pockets of gas should form in the first place and why they should be maintained in the wall and mesentery of the colon. Counterperfusion supersaturation could explain the formation and location of the gas cysts, which occur mostly near blood vessels on the mesenteric border of the colon, and the absence of methane gas in them. The hypothesis can be tested by treating patients with pneumatosis cystoides coli with heliox.

Pneumatosis cystoides intestinalis and high breath H2 excretion: insights into the role of H2 in this condition

Patients with pneumatosis cystoides intestinalis have been reported to excrete excessive H2 because of a lack of H2-consuming intestinal bacteria. This study describes a patient with bacterial overgrowth and pneumatosis of the small intestine whose colonic flora avidly consumed H2 but whose small bowel flora produced but did not consume H2. There is no commonly accepted mechanism whereby excessive luminal H2 causes intramural gas. An explanation is proposed in which an initial, transitory source of intramural gas is distinguished from the mechanism that results in the persistence of the gas. Independent of the initial source of gas, rapid diffusion of H2 from the lumen into an intramural gas bubble would cause N2, O2, and CO2 to diffuse from the blood into the bubble. As a result, the bubble would expand and then persist indefinitely as long as H2 continued to diffuse from the lumen to the intramural gas collection.

Detection of malabsorption of low doses of carbohydrate: accuracy of various breath H2 criteria

BACKGROUND

Although the accuracy of breath H2 testing to detect malabsorption of small (< 50 g) doses of carbohydrate has never been evaluated, studies suggest that its accuracy is limited by a high prevalence of "H2 nonproducers." The aim of this study was to determine the accuracy of H2 breath testing in the detection of malabsorption of 10 g of carbohydrate.

METHODS

In 55 healthy subjects, we determined the ability of breath H2 measurements to distinguish between the ingestion of 10 g of a nonabsorbable carbohydrate (lactulose) and two control meals, a nonabsorbable electrolyte solution or glucose (10 g).

RESULTS

The conventional criterion of a 20 ppm increase in breath H2 had 100% specificity but failed to identify lactulose malabsorption in 47% and 24% of subjects at 4 and 8 hours of testing. In contrast, a breath H2 of > 6 ppm at 5 or 6 hours had near perfect specificity and sensitivity. A sum of breath H2 at 5, 6, and 7 hours of > 15 ppm yielded perfect separation between lactulose and control solutions.

CONCLUSIONS

True "H2 nonproducers" are extremely rare. Using appropriate criteria, breath H2 testing provides a very accurate means of identifying malabsorption of low doses of carbohydrate.

Impaired hydrogen metabolism in pneumatosis cystoides intestinalis

BACKGROUND

Pneumatosis cystoides intestinalis (PCI) is characterized by high levels of breath hydrogen. Clinical features of PCI may be due to abnormal H2 metabolism.

METHODS

Breath levels of H2 and CH4 were measured in 3 patients and total gas in 2 patients with PCI on a polysaccharide-free (basal) diet and after administration of 15 g of lactulose. Metabolic activities and counts of methanogenic (MB) and sulfate-reducing (SRB) bacteria were measured in feces. Ten volunteers were also studied.

RESULTS

Total H2 levels in patients were 383-420 mL/day on the basal diet and 1430-1730 mL/day after lactulose administration compared with 35 +/- 6 mL/day and 262 +/- 65 mL/day, respectively, in controls. Basal breath H2 levels in controls were 27 +/- 6 vs. 214 +/- 27 mL/day in patients and after lactulose ingestion, 115 +/- 18 vs. 370 +/- 72 mL/day. Four controls were methanogenic and had high fecal MB counts. The other controls had high SRB counts and sulfate reduction rates. All patients were nonmethanogenic and had low sulfate reduction rates.

CONCLUSIONS

Patients with PCI excrete more H2 than controls. In normal subjects, H2 is consumed by MB or SRB; the activity of these bacteria is virtually absent in PCI. This may explain the gas accumulation in these patients.

Methodological aspects of breath hydrogen (H2) analysis. Evaluation of a H2 monitor and interpretation of the breath H2 test

The reliability of end-expiratory hydrogen (H2) breath tests were assessed and the significance of some important pitfalls were studied, using a compact, rapid H2-monitor with electrochemical cells. The H2 response was shown to be linear and stable. The reproducibility of the breath collection technique was determined in 20 patients following ingestion of lactulose. The increment between consecutive means of duplicate samples indicative of a significant rise of H2 concentration never exceeded 10 p.p.m., the mean coefficient of variation of the duplicate samples was below 5%. Fasting H2 levels were studied in 10 healthy adults during a 4-month period and they showed very marked inter- and intra-individual variability (16% above 40 p.p.m.). Initial peaks (early, short-lived H2 rises unrelated to carbohydrate malabsorption) were identified in 25% of the breath tests (in 4% above 20 p.p.m). It is concluded that the technique used for interval sampling of end-expiratory breath samples for H2 concentration gives reliable results. The biological significance of H2 concentration increments can only be evaluated if the limitations of the technical procedures and the individual ability to produce H2 is known.

Fasting breath hydrogen in celiac disease

We studied the possible clinical significance of high basal levels of H2 by analyzing the breath excreted by the following fasting subjects: 50 healthy volunteers, 149 subjects with functional bowel disorders, 16 patients with small bowel bacterial overgrowth proven by bacteriology, 34 patients with untreated celiac disease, 40 patients with celiac disease on a gluten-free diet, and 40 patients with disorders of the small intestine other than celiac disease (disease controls). The fasting levels of H2 in untreated celiac patients (mean 22.5 +/- 19.3 ppm) were significantly higher than those in healthy volunteers (5.8 +/- 3.1 ppm), patients with functional bowel disorders (6.6 +/- 4.4 ppm), treated celiac patients (9.9 +/- 8.1 ppm), and disease controls (7.0 +/- 6.7 ppm). No significant difference was found between patients with untreated celiac disease and bacterial overgrowth (mean 14.7 +/- 14.0 ppm). The percentage of patients with elevated H2 fasting levels in untreated celiac disease (58.8%) was significantly higher than that in the other groups, except for the patients with bacterial overgrowth (43.7%). In 14 celiac patients, studied before and after a gluten-free diet, fasting H2 levels decreased from 26.6 +/- 18 to 11.6 +/- 10 ppm, becoming normal only in those patients with healing of intestinal lesions. Our results show that high fasting H2 levels are a frequent feature of untreated celiac disease and that the return to normal of these levels is predictive of villous regrowth.

A new health problem due to trichloroethylene: pneumatosis cystoides intestinalis

The relationship between pneumatosis cystoides intestinalis (PCI) and occupation was studied in 66 patients reported in Japan during a 5-yr-period from 1979-1983. Information concerning their occupation was obtained from 37 (56.1%) patients; 16 patients had secondary PCI and 21 had primary PCI. No particular characteristics were noted in the occupations of secondary PCI patients. Primary PCI, occurring more frequently in females (15/21), affected predominantly the large intestine (20/21), locally involving the sigmoid colon in the majority (14) of the patients. Most patients with primary PCI (16/21) were factory workers, of whom 15 (71.4%) were engaged in degreasing of manufacturing products with trichloroethylene. The high percentage of trichloroethylene workers among the patients with primary PCI suggests that occupational exposure to this agent constitutes an etiological factor in the development of this disease.

Pneumatosis cystoides intestinalis. A review of the literature

Pneumatosis cystoides intestinalis is a condition in which submucosal or subserosal gas cysts are found in the wall of the small or large bowel. Both fulminant and benign forms exist. Fulminant pneumatosis cystoides intestinalis is associated with an acute bacterial process, sepsis, and necrosis of the bowel, while benign pneumatosis cystoides intestinalis can be totally asymptomatic and observed as an incidental finding at laparotomy. Many different causes of pneumatosis cystoides intestinalis have been proposed, including mechanical and bacterial causes. A review of the literature is presented with emphasis on the etiology of pneumatosis cystoides intestinalis, which probably can be attributed to bacterial and mechanical factors. Diagnosis and different forms of therapy and their efficacy are also discussed.

The hydrogen (H2) breath test. Sampling methods and the influence of dietary fibre on fasting level

Three end-expiratory breath hydrogen (H2) sampling methods were compared in a patient group (n = 12) and a laboratory staff group (n = 12) on two separate occasions. H2 samples obtained with each method showed significantly different concentrations (p less than 0.001) but no significant differences in coefficient of variation when individual triplicate samples were evaluated. There was a high correlation between the breath H2 concentrations obtained by the three methods (r = 0.93-0.96). Fasting breath H2 values after an overnight fast and an unrestricted diet the day before the investigation were compared with values obtained after an overnight fast and a low-fibre diet the day before the test in two patient groups (n = 39 and 39) with a comparable distribution of diagnoses and in one group of healthy volunteers (n = 17). Fasting breath H2 concentrations were significantly lower after a low-fibre diet in the patient groups (p less than 0.005) and in healthy volunteers (p less than 0.02). We conclude that each of the three end-expiratory sampling methods can be chosen for use in H2 breath tests depending on suitability and convenience and that a low-fibre diet the day before the H2 breath test lowers fasting breath H2 concentration.

The mucosal changes and pathogenesis of pneumatosis cystoides intestinalis

The clinical and pathologic findings in 11 patients with pneumatosis cystoides intestinalis (PCI) are described. Symptoms were variable but localized to the gastrointestinal tract. Only one patient had obstructive airway disease. Although gas cysts of varying sizes were present in the colonic wall in all cases, distinctive changes were also observed in the mucosa. Architectural disturbances were seen in 11 of 13 specimens, and changes mimicking those of inflammatory bowel disease, including cryptitis, crypt abscesses, chronic inflammation, and granulomas, were present. In addition, crypt dilation and partial crypt rupture, with formation of intramucosal cysts, were seen in association with clusters of small gas cysts in the lamina propria. The transgression of gas cysts through the muscularis mucosae and the presence of larger giant cell-lined cysts in the submucosa suggested entry of gas generated in the colonic lumen or within inflamed crypts from the mucosal aspect. Other postulated pathogeneses of PCI are discussed.

Is raised breath hydrogen related to the pathogenesis of pneumatosis coli?

Clinical and physiological studies were carried out in five patients with pneumatosis coli in order to investigate the origin of the high fasting breath hydrogen concentration in this condition and to determine its possible significance in the pathogenesis of the disease. All five patients excreted abnormally high fasting concentrations of hydrogen in their breath (69 +/- 9 ppm, mean +/- SEM). Moreover, analysis of the contents of the gas filled cysts revealed between 2% and 8% of hydrogen gas. Colonic washout significantly reduced breath hydrogen concentrations to 9 +/- 6 ppm, but did not abolish the cysts. Conversely, deflation of the cysts was achieved with oxygen or antibiotics, though this only reduced breath hydrogen concentrations to about 66% of their original value. After feeding a radiolabelled meal, breath hydrogen concentrations rose before the meal appeared to reach the colon, suggesting overgrowth of anaerobic bacteria in the small intestine. Despite this, 14C glycocholate breath tests were within normal limits. An alternative possibility is that the high levels of hydrogen excreted in the breath may be produced in the intestinal lumen possibly from the fermentation of copious amounts of colonic mucus. Finally, measurement of whole gut transit time and stool weight suggested that patients were constipated despite passing mucus and blood. The relevance of our observations to the pathogenesis of submucosal cysts is unclear, but the data favour the hypothesis that these are produced by invasion of the colonic submucosa with anaerobic bacteria.

Prolonged small-intestinal transit time in cystic fibrosis

A lactulose hydrogen breath test was performed on 10 patients with cystic fibrosis and 15 control subjects matched for age and sex. All normal subjects had a fasting breath hydrogen concentration of less than 20 ppm. In contrast, seven of the patients with cystic fibrosis had high concentrations (25-170 ppm), which fell to 20 ppm or below on prolonged fasting (14-23 hours). Two patients showed no rise in breath hydrogen concentrations after lactulose, and in one patient the breath hydrogen concentration rose at 15 minutes, suggesting bacterial colonisation of the small bowel. Seven of the patients had prolonged small-bowel transit times (160-390 minutes) compared with those in the control group (50-150 minutes).

Oxygen therapy in pneumatosis coli. What is the minimum oxygen requirement?

Breathing high concentrations of oxygen at atmospheric pressure has been effective in achieving prompt objective and subjective relief in pneumatosis coli. A 22-year-old man was treated with 40% oxygen--a smaller concentration than used by previous physicians--supplied through a nonrebreathing mask. During meals, oxygen was given at 5 1/minute by nasal cannula. Oxygen therapy was maintained for seven days. A year after treatment the patient was still asymptomatic and free from disease. Using this therapeutic measure the benefit/risk ratio of oxygen therapy could be increased.

Pneumatosis cystoides intestinalis associated with pyloric stenosis

Pneumatosis cystoides intestinalis is a rare condition characterized by the presence of gas-filled cysts in the bowel wall. A case is reported which was associated with peptic ulcer and in which there was involvement of the ileum and pre-pyloric region of the stomach. Stomach involvement is a rare occurrence. Chronic pneumoperitoneum was also present. The mechanism of its occurrence is discussed.

Pneumatosis coli: case report documenting time from X-ray appearance to onset of symptoms

Pneumatosis coli was diagnosed in a 66-year-old atopic woman with a 6-month history of chronic cough and intermittent wheeze. A sequence of chest x-rays demonstrated the appearance of gas-filled cysts in the splenic flexure of the colon approximately 2 months before the development of bowel symptoms. The pneumatosis coli and symptoms disappeared in 6 days with the administration of oxygen at a flow rate of 6 liters/min by nasal prongs. The case demonstrates the slow progression of the condition from x-ray recognition to development of symptoms and the simple, effective treatment of the condition with nasal oxygen.

Pneumatosis coli and sigmoid volvulus: a report of 4 cases

Pneumatosis coli is an uncommon disease which is frequently misdiagnosed and inappropriately treated. The condition can usually be managed conservatively but complications requiring surgical treatment are occasionally encountered. We describe 4 patients with pneumatosis coli and associated volvulus of the sigmoid colon. Some of the factors that may have contributed to pneumocyst formation in these 4 patients are discussed with reference to recent advances in our understanding of the pathogenesis of pneumatosis coli.