nfantile hypertrophic pyloric stenosis (IHPS) is a common cause of gastric outlet obstruction in infants, and presents as one of the most common surgical conditions of infancy. The lesion is characterized by gastric outlet obstruction and multiple anatomic abnormalities of pyloric antrum.

The etiology of (IHPS) is obscure but probably is a multifactorial, involving genetic predisposition and environmental factors. Typically; infants with IHPS are clinically normal at birth, but during the first few weeks of postnatal life; they develops non bilious forceful vomiting described as "projectile" (1) .

The clinical diagnosis hinges on the palpation of the thickened pylorus or "olive " Abdominal examination is accurate but not always successful, depending on factors such as the experience of the examiner ,the presence of gastric distention and , a calm infant. (2) Surgical treatment is curative. The classical operation is a Ramsted's Pyloromyotomy; which may also be performed laparoscopically Current imaging techniques, particularly sonography, are noninvasive and accurate for identification of (IHPS) (3) .

There was very few published study in our local literature. So we conduct this study to investigate IHPS in form of, presentation, management and overall outcome.

In this prospective cross -sectional, hospital based study; 42 patients with IHPS, were admitted in Khartoum Teaching hospital department of Pediatric Surgery in the period between Aug. 2011 and May. 2013. Patients were referred from all parts of Sudan. Study variables included were age, gender, and residence, presenting symptoms, clinical sign and postoperative outcomes. Data was collected using a structured, pretested questionnaire and analyzed using a computer program-Statistical Package for Social Sciences (SPSS) version 20. Results were presented in tables and graphs.

Forty two patients were admitted in Khartoum Teaching hospital, department of Pediatric Surgery, from Aug 2011 to May2013; with IHPS. Clinically 42(100%) of the patients presented projectile vomiting; which found to be non bilious in 41(97.6%) patients. 34(81.0%) of the patients had marked weight loss while 24(57.1) of them present with constipation.

Regarding clinical examination 37(88.1%) of the patients were dehydrated, 38(90.5%) had palpable epigastric olive like mass while just 29(69.0%) of them had visible peristaltic wave. With 24(57.1) of the patient had abdominal distension.

Thirty (71.4%) patients had normal Hb level, 24(57.1%) showed low serum K + level compared to 18(42.9) with low serum Na + . 8(19%) of the patient had high blood urea level, while just one (2.4%) had elevated serum creatinine.

Abdominal U/S done for all patient; which confirm the diagnosis in 41(97.6%) of the patients, while contrast study was needed to confirm the diagnosis just in one (2.4%) patient.

All the 42 patients received open surgical intervention, and Ramsted's pyloromyotomy was done successfully to all patients; with only 4.8% complication, and 2.4% mortality Twenty five (59.5%) of our patients had an average postoperative stay of 48 hours.

Although there were many published studies about IHPS worldwide; there was very few published study in our local literature. So we conduct this study to investigate IHPS in form of, presentation, management and overall outcome.

In our study we reviewed 42 patients; admitted in Khartoum Teaching hospital department of Pediatric Surgery with IHPS; from Aug. 2011 to May. 2013. Comparison of our study with the AC Paul, etal (6) , Frieda Hulka, etal (8) , Jlidi S, etal (9) , Taylor, etal (4) , and ?smet Faruk ÖZGÜNER, etal (7) revealed several similar results and many important differences.

Most of our patients (61.9%) were between 3-6 weeks of age group. That's goes with the results of in comparison studies (4,6,7,8,9) .

In our study there is a male gender dominance (78.6%), with a male to female ratio of (3.7:1); and that's goes with all the above mentioned studies (4,6,7,8,9) , with a male to femal ratio ranging from (3.8:1) in Jlidi S, etal (9) to (10:1) in AC Paul, etal (6) study.

With regards AC Paul, et al (6) study, he found among 70 male, 49(70%) were a first born male child, and that's goes with our results as (50%) of our patients were a first born male.

Regarding the clinical presentation, 42 (100%) of the patients presented with projectile vomiting; which found to be non bilious in 41 (97.6%) patients. (81.0%) of the patients had marked weight loss while (88.1%) of the patients were dehydrated, (90.5%) had palpable epigastric olive like mass and (69.0%) of them had visible peristaltic wave. That's comparable to most of the previously mentioned studies; (83.6%) of the patients had the typical history of projectile vomiting and the typical findings of visible peristalsis after a "test meal" and a palpable pyloric tumor in ?smet Faruk ÖZGÜNER, etal (7) study, and palpable olive like epigastric mass was found in up to (92%) of patents in Sapkota. S (5) study,while olive' was palpated on examination in 48%, and visible peristalsis seen in 25% in Taylor, etal (4) study. And that variation is most probably due to patients built; as these sign more obvious in thin wasted patients, beside that the state of gastric fullness also affect the examination finding; as full stomach make a peristaltic wave visible, while an empty stomach facilitate palpation of an olive like epigastric mass.

Thirty (71.4%) patients had normal Hb level, 24(57.1%) showed low serum K + level compared to 18(42.9) with low serum Na + . Eight (19%) of the patient had high blood urea level, while just one (2.4%) had elevated serum creatinine. (Table4).

Abdominal U/S done for all patient; which confirm the diagnosis in 41(97.6%) of the patients, while contrast study was needed to confirm the diagnosis just in one (2.4%) patient.

All patients received open surgical intervention, and Ramsted's pyloromyotomy was done successfully to all patients; with only 4.8% complication; in form of inadvertent simple mucosal perforation; repaired with 4/0 vicryl, and wound dehiscence for 1 (2.4%). We had a 1 (2.4%) mortality. Over all outcome of our study is comparable to the international results, for example; AC Paul, etal (6) had Inadvertent mucosal perforation occurred in 1 case during procedure and Superficial wound infection found in 3 cases (03.89%), Twenty five (59.5) had average postoperative stay of 48 hours, AC Paul, etal (5) had 65 (84.41%) patients were discharged on 3 rd to 4th postoperative day.