Hypertrophic pyloric stenosis

Low level of NO involved in causation of pylorospasm in infantile hypertrophic pyloric stenosis... 

Pylorospasm and hypertrophic pyloric stenosis is associated with early postnatal erythromycin exposure and has been observed in neonates after 1-2 days of oral erjdhromycin therapy (30). The prominent gastrokinetic properties of erythromycin have been postulated as the mechanism (31). 

The use of erythromycin in postexposure prophylaxis for pertussis in 200 infants was followed by an increased number of cases of infantile hypertrophic pyloric stenosis, and all seven cases had taken erythromycin prophylacti-cally (33). A case review and cohort study supported these preliminary findings (34). In a retrospective study in 314 029 children, very early exposure to erythromycin (at 3-13 days of life) was associated with a nearly eightfold increased risk of pyloric stenosis (35). There was no increased risk in infants exposed to erythromycin after 13 days of hfe or in infants exposed to antibiotics other than erythromycin. 

SanFilippo A. Infantile hypertrophic pyloric stenosis related to ingestion of erythromycine estolate A report of five cases. J Pediatr Surg 1976 11(2) 177-80. 

Hauben M, Amsden GW. The association of erythromycin and infantile hypertrophic pyloric stenosis causal or coincidental Drug Saf. 2002 25(13) 929 2. 

Centers for Disease Control and Prevention (CDC). Hypertrophic pyloric stenosis in infants following pertussis prophylaxis with erythromycin—Knoxvihe, Tennessee, 1999. MMWR Morb Mortal Wkly Rep 1999 48(49) ... 

Honein MA, Paulozzi LJ, Himelright IM, Lee B, Cragan JD, Patterson L, Correa A, Hall S, Erickson JD. Infantile hypertrophic pyloric stenosis after pertussis prophylaxis with erythromcyin a case review and cohort study. Lancet 1999 354(9196) 2101-5. 

Cooper WO, Griffin MR, Arbogast P, Hickson GB, Gautam S, Ray WA. Very early exposure to erythromycin and infantile hypertrophic pyloric stenosis. Arch Pediatr Adolesc Med 2002 156(7) 647-50. 

Pyloric stenosis may lead to obstruction of the lumen and usually presents beyond the neonatal period. However, it has been diagnosed in utero and can be seen in the neonatal period after administration of prostaglandin E to infants with ductus-dependent congenital heart disease. The stenosis is produced by central foveolar hyperplasia. On sonography, mucosal thickening often with polypoid or lobular appearance is observed, different from the muscular thickening observed in hypertrophic pyloric stenosis (Peled et al. 1992 Babyn et al. 1995) (Fig. 1.2). 

Ultrasound (US) is now increasingly used for the evaluation of the upper GI tract, for instance to evaluate for wall thickness or a duplication cyst. In other instances, it may be necessary to fill the stomach with fluid before the examination, e.g. in the evaluation of gastroesophageal reflux or hypertrophic pyloric stenosis. 

On barium studies a strikingly nodular pattern in the gastric antrum can be seen with relative sparing ofthe body and fundus (lEELEetal. 1979) (Fig. 3.15). Hummer-Ehret et al. (1998) reported that eosinophilic gastroenteritis could mimic hypertrophic pyloric stenosis on US. 

Anagnostara A, Koumanidou C, Vakaki M, Manoli E, Kaka-vakis K (2003) Chronic gastric volvulus and hypertrophic pyloric stenosis in an infant. I Clin Ultrasound 31 383-386... 

Westra SJ, de Groot CJ, Smits NJ, Staalman CR (1989) Hypertrophic pyloric stenosis use of the pyloric volume measurement in early US diagnosis. Radiology 172 615-619... 

Susceptibility factors Breast-feeding infants Treatment of infants with macrolides has been associated with hypertrophic pyloric stenosis, causing projectile vomiting. 

Primary tuberculosis of stomach and duodenum is very rare and usually develops secondary to pulmonary tuberculosis. Simultaneous involvement of the duodenum occurs in 10% of patients. There is increased incidence in patients with AIDS. The radiological appearances are classified as predominantly ulcerative or hypertrophic type (Tishler 1979 Agrawal et al. 1999). The ulcerative form is more frequent and consists of multiple large and deep ulcerations, sometimes with antral fistulas (Fig. 5.10). In the hypertrophic form, there is thickening of stomach and duodenal folds which can lead to pyloric stenosis and gastric outlet obstruction. A narrowed antrum can mimic a linitis plastica appearance. There is usually extensive lymph node involvement in the adjacent areas (Tishler 1979 Agrawal et al. 1999). Sarcoidosis and syphilis have identical appearances on conventional barium studies, both ulcerative and hypertrophic (Fig. 5.11). 

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