Hemolytic uremic syndrome (HUS) is associated with consumption of under cooked gound beef, characterized by triad of renal failure, microangiopathic hemolytic anemia and thrombocytopenia. Early recognition of this disease, maintenance of fluid balance and proper dialysis seems to prevent acute mortality. A 23-month-old boy was admitted with abdominal pain, bloody diarrhea and fever. On hospital day (HD) #2, he developed aggravated abdominal pain compared to the initial assessment. Contrast abdominal computed tomography demonstrated findings suggestive acute appendicitis so the patient was underwent laparoscopic appendectomy. On HD #3 and #4, his laboratory findings showed marked thrombocytopenia and serum creatinine elevation. He was transferred to another hospital for dialysis with the impression of acute renal failure. Later, verotoxin-producing Escherichia coli, which is one of the most common causes of HUS, was detected on his initial stool examination. HUS can present with prodromal gastrointestinal symptoms mimicking acute abdomen. So even if the patient is primarily diagnosed acute abdomen in the initial setting, clinicians should always keep in mind of other fatal conditions disease, such as HUS. To our knowledge, this is the first case report of acute appendicitis followed by HUS in South Korea.

The entity of negative appendectomies still poses a dilemma in chlidren. Focused computed tomography (CT) scanning has become the diagnostic test of choice in many hospitals. However, the impact of CT scans on the diagnosis in children is unknown exactly. The purpose of this study was to critically evaluate CT scans for the evaluation of acute appendicitis in children, to review utilization of this diagnostic test in our appendicitis population and to determine if diagnostic accuracy has improved. A retrospective analysis of efficacy of CT scan for diagnosis of appendicitis in children was conducted. Children undergoing appendectomy for acute appendicitis were reviewed from 2007 to 2012. Perforation and negative appendectomy (removal of a normal appendix) rates were determined by the final pathologic report. Statistical comparison were made using the χ² test and significance was assigned at p < 0.05. Five hundred four appendectomies were performed. Mean age was 10.1 ± 3.21 years, and 62.7% were boys. Overall, 308 children (61.1%) underwent CT scanning, 100 (19.8%) had US performed, and 97 (19.2%) had no radiographic study. A pathologically normal appendix was removed in 8.7% (27 of 308) of CT patients, 9.0% (9 of 100) of US patients, and 11.3% (11 of 97) of patients without a study. The frequency of CT scanning increased from 29.7% (27 of 91) of all children in 2007 to 75.6% (59 of 78) in 2012, whereas utilization of US decreased from 30.8% (28 of 91) to 11.5% (9 of 78). During this time period the difference in the negative appendectomy rate did change significantly from 14% to 6%. Liberal use of CT scans in diagnosing appendicitis in children has resulted in a decreased negative appendectomy rate.

Acute appendicitis is very rare in premature neonates. Preoperative diagnosis of this condition is difficult, and then it leads to high morbidity and mortality. We report 9-day-old premature male with ruptured acute appendicitis presented with pneumoperitoneum on plain films of the abdomen. Awareness of this rare condition and possible differential diagnosis in this age group is also discussed.

Acute appendicitis is one of the most common diseases of young people that requires emergency operation. This is especially true for those age 10 years old and older. However, the numbers of cases of appendicitis are increasing in both the young and the elderly. The main purpose of this study is to understand the clinical features of acute appendicitis in children and elderly patients. We retrospectively compared clinical characteristics in 4 groups of patients who underwent appendectomy in our hospital. There were 16 patients in the pre-school age group, 9 were males and 7 females. The total number of patients in the juvenile group were 287, 156 were males and 131 females. The total numbers of patients in the adult group were 794, 436 were males and 358 females. The numbers of elderly patients were 189, 91 were males and 98 females. Complicated appendicitis was found in 15 patients (93.7 %) in the pre-school age group, 79 patients (27.5 %) in the juvenile group, 332 patients (41.8 %) in the adult group, and 96 patients (50.7 %) in the elderly group. Four patients (40 %) had generalized panperitonitis in the pre-school group. The occurrence of perforated appendicitis was the highest in the pre-school age group and the lowest in the juvenile group. Since generalized panperitonitis has a higher incidence in the pre-school age group, prudent and careful diagnosis and treatment are required for the pre-school age group.

A nationwide survey on acute appendicitis (AAP) was undertaken among members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and the case registration form for each patient during the 6 months period from the 1st October, 2005 to 31st March, 2006. Questionnaires were collected from 23 members. Four hundred seventy six patients were registered from 21 hospitals where the members were working. The male to female ratio was 1.67:1. Average age was 9 years and 5 months (range 21 months-20 years). Operations were performed on average 10.4 hours (range 1-230 hours) from arrival at hospital. The average operation time was 59.1 minutes. The average admission days were 5.8 days (range 2-45 days). The most frequent symptoms were abdominal pain (95.1%), vomiting (50.6%) and fever (43.7%). The average duration of symptoms was 42.2 hours (range 1 hour-22 days). Leukocytosis (WBC count>10,000) was found in 85.9%. The most popular diagnostic tools were ultrasonography and CT. Open surgery was performed in 72.1% and laparoscopic surgery in 27.5%. Two laparoscopic surgeries were converted to open surgery (0.4%). Simple appendicitis was found in 54.5% and complicated appendicitis such as abscess, gangrenous change and perforation in 45.5%. According to the questionnaires 12 hospitals were performing open surgery only in all patients. Four hospitals were performing laparoscopic surgery in all patients. Seven hospitals are performing both surgical methods according to surgeon or occasion. Regarding the use of antibiotics in acute appendicitis, three kinds of antibiotics were used in 40% of total simple appendicitis patients. The results showed the trend of management in acute appendicitis in Korea. Especially it is necessary for the members to discuss the use of antibiotics for prophylaxis in the simple appendicitis

Pediatric laparoscopic appendectomy is controversial particularly in complicated appendicitis. We evaluated the outcomes of laparoscopic appendectomy (LA) and open appendectomy (OA) in simple appendicitis and complicated appendicitis respectively. Since June 2004, initial LA has been our policy in all appendicitis including complicated ones. A total of 160 patients were included in this study, consisting of 80 OA (August 2001 . August 2003) and 80 LA (June 2004 . June 2006). We compared the operating time, the length of hospital stay, the length of antibiotics use, and the postoperative complications between LA and OA. In simple appendicitis (73), there were no differences between LA and OA. However in the 87 patients with complicated appendicitis, the operating time was longer in LA (64.8 min vs. 50.2 min) but the length of hospital stay was shorter in LA than OA (8.5 days vs. 9.6 days). There was one complication in simple appendicitis group and six in complicated appendicitis group (3 cases in LA, 3 cases in OA). There was no difference in the results of LA versus OA in simple appendicitis. Therefore for simple appendicitis, LA is recommended in consideration of the cosmetic effect (fewer scar). In complicated appendicitis, early discharge was an advantage and there were no differences in complications in LA despite a longer operative time. So we conclude LA can be considered as the first choice of treatment for all pediatric appendicitis including complicated appendicitis. To confirm our impressions, more well controlled randomized prospective studied need to be done.

Appendicitis is a common disease in children. But left lower abdominal pain in acute appendicitis is a rare clinical feature. A 6 year-old-girl complained of left sided abdominal pain for 2 days. Past medical history was not contributory. Abdominal tenderness and guarding in left lower quadrant were noticed. Abdominal sonography and abdominal computed tomography scan demonstrated reversed position between superior mesenteric artery and vein, and a mass in the left lower quadrant abdomen suggesting appendicitis. Acute appendicitis in left lower quadrant, associated with intestinal malrotation, was found at laparatomy.

Appendectomy is the most common emergency surgical operation in children. The laparoscopic treatment of pediatric appendicitis is controversial, particularly in complicated cases. The purpose of this study is to evaluate laparoscopic appendectomy (LA) and open appendectomy (OA) for simple and perforated appendicitis (SA, PA) in children. A total of 188 patients, operated from January 1992 to September 2003, were reviewed. Ninety-one patients underwent OA (65 SA and 26 PA) and 97 had LA ( 67 SA, 30 PA). There was one conversion of LA to OA in PA. Operative time for LA was longer for OA in PA (55.8 vs. 45.7 min; p=0.0467). Recovery of bowel movement, diet starting time, length of hospital stay for LA were significantly shorter than those for OA. Postoperative complication rate was not different between LA and OA in each group. Laparoscopic appendectomy is a safe and effective method for both simple and perforated appendicitis.

Intestinal obstruction secondary to intraabdominal adhesion is a well-known postoperative complication occurring after appendectomy. The aim of this study was to measure the incidence and clinical manifestations of mechanical intestinal obstruction after appendectomy for perforated appendicitis. We reviewed all of the children (age <16 years) who had been treated for appendicitis at Asan Medical Center between January 1996 and December 2001. Inclusion criterion included either gross or microscopic evidence of appendiceal perforation. Exclusion criteria were interval appendectomy, and patients immune compromised by chemotherapy. Associations of intestinal obstruction with age, sex, operation time, and use of peritoneal drains were analyzed. Four hundred and sixty two open appendectomies for appendicitis were performed at our department. One hundred and seventeen children were treated for perforated appendicitis (78 boys, 39 girls). The mean age was 8.9 years (range 1.5 to 14.8 years). There were no deaths. Eight patients were readmitted due to intestinal obstruction, but there was no readmission due to intestinal obstruction in patients with non-perforated appendicitis. The interval between appendectomy and intestinal obstruction varied from 12 days to 2 year 7 months. Four patients needed laparotomies. In three of four, only adhesiolysis was performed. One child needed small bowel resection combined with adhesiolysis. There was no significant association between age or sex and the development of intestinal obstruction. This was no association with operative time or use of peritoneal drain. Patients who required appendectomy for perforated appendicitis have a higher incidence of postoperative intestinal obstruction than those with nonperforated appendicitis. For the patients with perforated appendicitis, careful operative procedures as well as pre and postoperative managements are required to reduce adhesions and subsequent bowel obstruction.

Diagnosis of acute appendicitis in children is sometimes difficult. The aim of this study is to validate a clinical scoring system and ultrasonography for the early diagnosis and treatment of appendicitis in childhood. This is a prospective study on 59 children admitted with abdominal pain at St. Mary's Hospital, the Catholic University of Korea from July 2002 to August 2003. We applied Madan Samuel's Pediatric Appendicitis Score (PAS) based on preoperative history, physical examination, laboratory finding and ultrasonography. This study was designed as follows: patients with score 5 or less were observed regardless of the positive ultrasonographic finding, patients with score 6 and 7 were decided according to the ultrasonogram and patients above score 8 were operated in spite of negative ultrasonographic finding. The patients were divided into two groups, appendicitis (group A) and non-appendicitis groups (group B). Group A consisted of 36 cases and Group B, 23 cases. Mean score of group A was 8.75 and group B was 6.13 (p<0.001). Comparing the diagnostic methods in acute appendicitis by surveying sensitivity, specificity, positive predictive value, negative predictive value, and accuracy, PAS gave 1.0000, 0.3043, 0.6923, 1.0000, and 0.7288, and ultrasonography gave 0.7778, 0.9130, 0.9333, 0.7241, and 0.8300 while the combined test gave 1.0000, 0.8696, 0.9231, 1.0000, and 0.9490, respectively. Negative laparotomy rate was 3 %. In conclusion, the combination of PAS and ultrasonography is a more accurate diagnostic tool than either PAS or ultrasonography.