Streptococcus milleri in intraabdominal abscesses in children after appendectomy: incidence and course Marjolein M.N. Leeuwenburgh a, ⁎ , Valerie Monpellier a , Bart J.M. Vlaminckx b , Peter M.N.Y.H. Go a a Department of Surgery, Sint Antonius Hospital, Mailbox 2500, 3430 EM Nieuwegein, The Netherlands b Department of Microbiology and Immunology, Sint Antonius Hospital, Mailbox 2500, 3430 EM Nieuwegein, The Netherlands Received 13 December 2010; revised 2 August 2011; accepted 8 August 2011 Key words: Acute appendicitis; Streptococcus milleri; Intraabdominal abscess; Children Abstract Introduction: Intraabdominal abscesses are a common complication after appendectomy, especially in children. In this study, we describe the incidence and course of this complication in relation to the cultured pathogens found in intraabdominal abscesses. Methods: The charts of all patients between 1 and 18 years of age undergoing appendectomy in 3 hospitals between January 2006, and July 2009, were retrospectively reviewed. Presence of an intraabdominal abscess was confirmed with abdominal ultrasound examination. We collected all details concerning the appendectomy, pus cultures, and postoperative course in these patients. Results: Two hundred fifty-nine patients underwent appendectomy during the study period. Subsequently, abdominal ultrasound studies showed an intraabdominal abscess in 18 (7%) patients. Intraabdominal abscesses developed more frequently after perforated appendicitis (23%) than after simple appendicitis (2%). The incidence of postoperative abscesses did not differ significantly between open (5.6%) or laparoscopic (6.3%) appendectomy. However, the rate was high (38%) in the patients in whom the appendectomy was converted from laparoscopic to open. In 15 out of the 18 patients with a postoperative abscess drainage was performed. In pus cultures of the drained abscesses Streptococcus milleri and Escherichia coli were the most commonly isolated pathogens. Presence of S milleri was associated with prolonged hospital stay (13.9 versus 9.0 days, P = .105) and prolonged antibiotic treatment (11.3 versus 4.8 days, P = .203). Conclusions: The incidence of intraabdominal abscesses is high after perforated appendicitis in children (23%). Our data suggest that the presence of S milleri correlates with a more complicated postoperative course after appendectomy in children. © 2012 Elsevier Inc. All rights reserved. Formation of intraabdominal abscesses after appendec- tomy is one of the major complications of acute appendicitis in children. It is an important cause of prolonged hospital stay or readmission. Preoperative identification of patients prone to develop intraabdominal abscesses could enable us to develop a preventive strategy. ⁎ Corresponding author. E-mail addresses: m.m.leeuwenburgh@amc.uva.nl (M.M.N. Leeuwenburgh), v.monpellier@antoniusziekenhuis.nl (V. Monpellier), b.vlaminckx@antoniusziekenhuis.nl (B.J.M. Vlaminckx), go@antoniusziekenhuis.nl (P.M.N.Y.H. Go). www.elsevier.com/locate/jpedsurg 0022-3468/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2011.08.004 Journal of Pediatric Surgery (2012) 47, 535–539