Long-term effects of pyloromyotomy on pyloric motility and gastric emptying in humans

Controlled long term outcome of pyloromyotomy for pyloric stenosis: No long-term adverse effect

PURPOSE

Pyloromyotomy for pyloric stenosis is one of the more common surgical procedures performed on infants. The long-term effects of the procedure are however unclear. The purpose of this study was to study the effects into adult life, compare them with controls and to see if there is a need for structured follow up of patients.

METHODS

Of the 101 patients operated for pyloric stenosis between 1972 and 1974 at our tertiary referral center 91 could be traced. They were all invited to participate in the study and were sent validated questionnaires (PAGI-SYM, GIQLI) as well as a study-specific questionnaire examining the use of antacid drugs, incidence of gastroscopy and abdominal surgery. Sixty patients responded (66%, mean age 45 years, 46 male) and were included. Thereafter, 600 age and sex-matched controls were sent the same questionnaires. 132 responded (22%, 90 male) and were includes as controls.

RESULTS

No significant differences could be found in any of the examined parameters when looking at the whole material or the male patients. Female patients had higher PAGI-SYM-scores for post prandial fullness (mean 1.11 vs 0.43, P = 0.035) and heartburn (mean 0.59 vs 0.14, P = 0.043) when compared to controls.

CONCLUSIONS

The present study shows that most patients operated for pyloric stenosis during infancy experience no negative effects into adulthood. The finding in the female patient group is interesting but is unlikely to have any clinical implications. The results from this study strongly implicate that there is no need for follow up of patients into adulthood.

LEVEL OF EVIDENCE

Level III.

Case report: Late-onset hypertrophic pyloric stenosis in a 3-year-old boy: It is never too late

Hypertrophic Pyloric Stenosis (HPS) represents a relatively rare occurrence beyond infancy. Here, we present the case of a barely 3-year-old boy diagnosed with late-onset HPS and successfully treated with extra-mucosal pyloromyotomy. We review the literature, challenging the principle that more aggressive surgical approaches should be preferred over less invasive ones.

Targeting Mechano-Transcription Process as Therapeutic Intervention in Gastrointestinal Disorders

Mechano-transcription is a process whereby mechanical stress alters gene expression. The gastrointestinal (GI) tract is composed of a series of hollow organs, often encountered by transient or persistent mechanical stress. Recent studies have revealed that persistent mechanical stress is present in obstructive, functional, and inflammatory disorders and alters gene transcription in these conditions. Mechano-transcription of inflammatory molecules, pain mediators, pro-fibrotic and growth factors has been shown to play a key role in the development of motility dysfunction, visceral hypersensitivity, inflammation, and fibrosis in the gut. In particular, mechanical stress-induced cyclooxygenase-2 (COX-2) and certain pro-inflammatory mediators in gut smooth muscle cells are responsible for motility dysfunction and inflammatory process. Mechano-transcription of pain mediators such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) may lead to visceral hypersensitivity. Emerging evidence suggests that mechanical stress in the gut also leads to up-regulation of certain proliferative and pro-fibrotic mediators such as connective tissue growth factor (CTGF) and osteopontin (OPN), which may contribute to fibrostenotic Crohn's disease. In this review, we will discuss the pathophysiological significance of mechanical stress-induced expression of pro-inflammatory molecules, pain mediators, pro-fibrotic and growth factors in obstructive, inflammatory, and functional bowel disorders. We will also evaluate potential therapeutic targets of mechano-transcription process for the management of these disorders.

Microsomal Prostaglandin E Synthase-1 Plays a Critical Role in Long-term Motility Dysfunction after Bowel Obstruction

Motility dysfunction is present not only during bowel obstruction (BO), but after obstruction is resolved. Previous studies found that lumen distension associated mechano-transcription of COX-2 and production of PGE₂ in gut smooth muscle cells (SMC) account for motility dysfunction during obstruction. We hypothesized that PGE₂ may exert autocrine effect in SMC to induce microsomal prostaglandin E synthase-1 (mPGES-1), which contributes to motility dysfunction after obstruction is resolved. Partial colon obstruction was induced in rats with an obstruction band, which was released 7 days later. Rats were further studied in the post-BO state. Circular muscle contractility of the mid colon (previously distended during obstruction) remained suppressed, and colon transit was impaired in the post-BO state. The COX-2, mPGES-1, and PGE₂ levels were all increased in the distended bowel during obstruction. However, after obstruction was resolved, COX-2 expression returned to normal, whereas mPGES-1 and PGE₂ levels remained increased. Expression of mPGES-1 in colon SMC was inducible by stretch or PGE₂. Administration of mPGES-1 inhibitor Cay 10526 either before or after the release of obstruction normalized PGE₂ levels and improved motility in the post-BO rats. In conclusion, mPGES-1 plays a critical role in the continuous suppression of motor function in the post-BO state.

Adult idiopathic hypertrophic pyloric stenosis

Idiopathic hypertrophic pyloric stenosis (IHPS) is a predominantly infantile disease. The adult type of IHPS is extremely rare but it has been well recognized since the 19(th) century. We report a case of a 47-year-old male patient who presented with postprandial nausea and vomiting. He underwent upper gastrointestinal endoscopy, and gastric outlet obstruction was discovered. The upper gastrointestinal barium study showed a distended stomach with delayed gastric emptying due to pyloric stenosis. The abdominal computed tomography revealed thickening of the distal stomach. Since gastric malignancy could not be excluded, he underwent antrectomy with Billroth I anastomosis. The pathology revealed no malignancy but showed hypertrophy and hyperplasia of the inner circular muscle of the pylorus, which was compatible with IHPS. We reported the case to remind young physicians of this rare disease.

Advances in infantile hypertrophic pyloric stenosis

Infantile hypertrophic pyloric stenosis (IHPS) is a common condition in infancy, characterized by an acquired narrowing of the pylorus, which requires surgery. These infants usually present with projectile, nonbilious vomiting, with a palpable 'olive' in the abdomen and sometimes a 'peristaltic wave' after being fed with formula or breast milk. Although IHPS is a common disorder, its etiology is largely unknown. Surgical intervention is the standard treatment, preoperative preparation, however is essential to optimal outcome. In this review, the latest advances in IHPS regarding epidemiology, etiology, diagnostics and treatment will be discussed.

Late-onset hypertrophic pyloric stenosis: definition of diagnostic criteria and algorithm for the management

BACKGROUND AND PURPOSE

Gastric outlet obstruction (GOO) may be caused by various congenital and acquired conditions in children. The authors report 11 cases of GOO caused by muscular hypertrophy of the pylorus, which was proven histologically in 7. They describe this entity as "late-onset hypertrophic pyloric stenosis (HPS)," define the diagnostic criteria of the disease, and produce an algorithm for its management.

MATERIALS AND METHODS

The medical records of patients with GOO treated from 1999 and 2009 were retrospectively reviewed. Patients with infantile HPS and GOO secondary to corrosive ingestion or neoplasm were not included. Age, sex, family history, presenting symptoms and signs, radiologic methods and findings, type of management, histopathologic features, and outcome were noted for each patient.

RESULTS

Eleven patients (4 male, 7 female) ranging in age from 2 to 8 years (mean, 3.6 years) were included in the study. The symptoms were nonbilious vomiting (n = 11), abdominal pain (n = 4), and weight loss (n = 2). Abdominal ultrasound (n = 6) and upper gastrointestinal contrast studies were obtained (n = 11). Gastroscopy revealed complete (n = 6) or partial (n = 5) obstruction of the pylorus. Balloon dilatation of the pylorus was performed in 5 cases and repeated in 3 cases. Conservative treatment was initially attempted in 11 patients. Two patients with chronic gastritis and Helicobacter pylori (n = 2) were treated with amoxicillin-clavulanic acid, clarithromycin, and lansoprazole. A Billroth I procedure was performed in 7 cases. Hypertrophied pyloric muscle was noted in 7 patients and chronic gastritis in 2. The postoperative course was uneventful.

CONCLUSION

Hypertrophic pyloric stenosis is rarely seen after infancy. Analysis of our results and review of the literature prompted us to redescribe this entity as "late-onset HPS" and define the diagnostic criteria. Late-onset HPS is probably an acquired disease of unknown etiology. The management of late-onset HPS has been summarized in an algorithm, which will also be useful in the treatment of GOO in children caused by etiologies other than classical infantile HPS.

Endoscopic pyloroplasty with full-thickness transgastric and transduodenal myotomy with sutured closure

BACKGROUND

Pyloroplasty with myotomy and sutured closure is a surgical treatment for gastric outlet obstruction. It has not been previously performed at flexible endoscopy.

OBJECTIVE

To develop and test a method for performing a sutured pyloroplasty at flexible endoscopy.

DESIGN

A Heinicke-Miculicz pyloroplasty was performed, forming a linear myotomy through the pylorus from the gastric side into the duodenal bulb. This was subsequently sutured transversely to increase the opening. The operation was performed in 3 nonsurvival studies in pigs. The safety and the efficacy was then studied in 7 animals followed for up to 4 weeks after the procedure.

SETTING

The studies were performed in experimental surgical units in Gothenburg, Sweden, and London, UK.

INTERVENTIONS

A linear needle-knife incision was made through the pylorus; full-thickness sutures, by using a new T-tag and polypropylene thread suturing system through a flexible gastroscope, were placed to close the incision transversely. In 2 pigs, the prepyloric bulge was excised before the pyloroplasty.

RESULTS

Pyloroplasty was readily accomplished at flexible endoscopy in the 3 nonsurvival studies. Six of 7 pigs that survived in this study for periods of 7 to 28 days, recovered well, without complications. One pig (with bulge removal) developed gastric retention. The pyloric opening was increased; it was then easy to enter the duodenum at follow-up endoscopy.

LIMITATIONS

This method has yet to be studied clinically.

CONCLUSIONS

Pyloroplasty with full-thickness pyloromyotomy and transverse closure of a linear myotomy was accomplished by using a simple flexible endosurgical technique to test a new flexible suturing system.

Idiopathic hypertrophic pyloric stenosis combined with left paraduodenal hernia in an adult

OBJECTIVE

We report a case of primary hypertrophic pyloric stenosis combined with a paraduodenal hernia in a 35-year-old woman.

CLINICAL PRESENTATION AND INTERVENTION

The patient presented with signs of obstructive ileus. CT of the abdomen revealed a marked dilatation of the stomach and the proximal jejunum as well as a circumferential thickening of the antral-pyloric region with characteristics indicating hypertrophic pyloric stenosis. Exploratory laparotomy revealed the presence of a paraduodenal hernia containing jejunal loops and marked thickening of the pyloric region. The jejunum was reduced to its normal place and the ostium of the paraduodenal hernia closed with a running suture. The hypertrophic pyloric stenosis was treated with pyloromyotomy. Since the patient had no predisposing factors for the development of secondary pyloric stenosis, we considered the pyloric stenosis as congenital in origin.

CONCLUSION

To our knowledge this is the first reported case of congenital pyloric stenosis combined with the presence of a paraduodenal hernia in an adult.

Medical treatment of infantile hypertrophic pyloric stenosis: should we always slice the "olive"?

BACKGROUND/PURPOSE

Laparoscopic pyloromyotomy has recently gained wide acceptance as the optimum treatment of infantile hypertrophic pyloric stenosis (IHPS). However, medical treatment may be superior to laparoscopic surgery in invasiveness. The efficacy of our regimen of intravenous atropine therapy for IHPS was assessed in comparison with surgical treatment.

METHODS

Medical treatment was initially chosen for 52 (61%) of 85 infants with IHPS at our institute between 1996 and 2004. Atropine was given intravenously at 0.01 mg/kg 6 times a day before feeding. When vomiting ceased and the infants were able to ingest 150 mL/kg per day of formula after stepwise increases in the feeding volume, they were given 0.02 mg/kg atropine 6 times a day orally, and the dose was decreased stepwise.

RESULTS

Of the 52 patients, 45 (87%) ceased projectile vomiting with treatment using intravenous (median, 7 days) and subsequent oral (median, 44 days) atropine administration. The median hospital stay was 13 days (6-36), and no significant complications were encountered during atropine therapy. The remaining 7 patients required surgery. Of 40 who underwent surgery, 4 had wound infections and 1 with hemophilia had postoperative hemorrhagic shock. The patients who underwent successful atropine therapy had body weights comparable with those who underwent surgery at the age of 1 year.

CONCLUSIONS

The high success rate of intravenous atropine therapy for IHPS suggests that this therapy is an effective alternative to pyloromyotomy if the length of the hospital stay and the necessity of continuing oral atropine medication are accepted.

American Gastroenterological Association technical review on the diagnosis and treatment of gastroparesis

This literature review and the recommendations herein were prepared for the American Gastroenterological Association Clinical Practice Committee. The paper was approved by the Committee on May 16, 2004, and by the AGA Governing Board on September 23, 2004.

The treatment of diabetic gastroparesis with botulinum toxin injection of the pylorus

OBJECTIVE

Gastroparesis is a disorder of delayed gastric emptying that is often chronic in nature. Up to 50% of type 1 diabetic subjects have symptoms of gastroparesis, which include nausea, vomiting, and early satiety. Elevated pyloric pressures may be responsible for delayed gastric emptying in diabetic subjects. Botulinum toxin inhibits the release of acetylcholine and produces transient paralysis when injected into smooth muscle. The aim of this study was to determine whether injection of the pylorus with botulinum toxin in patients with diabetic gastroparesis improves symptoms of gastroparesis, alters gastric emptying scan time, and/or changes weight and insulin use.

RESEARCH DESIGN AND METHODS

This was an open-label trial with age- and sex-matched control subjects from a tertiary care referral center for patients with gastroparesis. Eight type 1 diabetic subjects (six women and two men; mean age 41 years; mean years with diabetes 25.3) who had failed standard therapy were enrolled. Intervention consisted of injection of the pylorus with 200 units of botulinum toxin during upper endoscopy. Symptoms, antropyloric manometry, gastric emptying scan times, weight, and insulin use were all recorded before intervention and during a 12-week follow-up period.

RESULTS

Seven of the eight patients completed the full 12-week follow-up period. No complications were noted. Mean symptom scores declined from 27 to 12.1 (P < 0.01), whereas the SF-36 physical functioning domain also improved (P < 0.05). Four patients noted an increase in insulin use of >5 units/day. Six of the seven patients gained weight (P = 0.05). Gastric emptying scan time improved in four patients.

CONCLUSIONS

Botulinum toxin injection of the pylorus is safe and improves symptoms in patients with diabetic gastroparesis. These results warrant further investigation with a large, double-blind, placebo-controlled trial.

Treatment of idiopathic gastroparesis with injection of botulinum toxin into the pyloric sphincter muscle

OBJECTIVES

We aimed to determine if botulinum toxin injection into the pyloric sphincter improves gastric emptying and reduces symptoms in patients with idiopathic gastroparesis.

METHODS

Patients with idiopathic gastroparesis not responding to prokinetic therapy underwent botulinum toxin (80-100 U, 20 U/ml) injection into the pyloric sphincter. Gastric emptying scintigraphy was performed before and 4 wk after treatment. Total symptom scores were obtained from the sum of eight upper GI symptoms graded on a scale from 0 (none) to 4 (extreme).

RESULTS

Ten patients were entered into the study. The mean percentage of solid gastric retention at 4 h improved from 27+/-6% (normal < 10%) before botulinum toxin injection into the pylorus to 14+/-4% (p = 0.038) 4 wk after treatment. The symptom score decreased from 15.3+/-1.7 at baseline to 9.0+/-1.9 (p = 0.006) at 4 wk, a 38+/-9% decrease. Improvement in symptoms tended to correlate with improved gastric emptying of solids (r = 0.565, p 0.086).

CONCLUSIONS

This initial pilot study suggests that botulinum toxin injection into the pylorus in patients with idiopathic gastroparesis improves both gastric emptying and symptoms.

Functional characteristics of the pylorus in patients undergoing pylorus--preserving gastrectomy for early gastric cancer

BACKGROUND

This study investigates the functional characteristics of the pylorus in patients undergoing pylorus-preserving gastrectomy (PPG) for early gastric cancer.

METHODS

In study 1, postprandial symptoms and gastric emptying were compared between 2 groups of 12 patients with early gastric cancer more than 1 year after either PPG (PPG group) or distal gastrectomy (DG) (DG group). Gastric emptying was evaluated with the dual isotope technique for liquids and solids separately. In study 2, pyloric motility was evaluated with a sleeve/sidehole manometric assembly in 7 patients undergoing PPG, which was compared with that in the preoperative patients.

RESULTS

In study 1, the overall modified Visick score of postprandial symptoms and the Sigstad dumping score were significantly lower in the PPG group compared with the DG group (P <.05). Early accelerated gastric emptying was observed in both groups for liquids, but only in the DG group for solids. In study 2, isolated pyloric pressure waves induced by intraduodenal lipid infusion and phase III-like activity induced by intravenous erythromycin infusion were preserved after PPG.

CONCLUSIONS

The quantitative analysis of postoperative symptoms revealed that PPG patients were associated with better clinical conditions than DG patients. The clinical benefits of PPG are considered to be based on the function of the preserved pylorus.