The study included the detection of bacterial species in 110 excised appendix being taken from 110 patients having acute appendicitis who were referred to Al-Kufa Teaching Hospital, department of urology whose ages ranged from 4 to 60 years old. The patients were 69 (62.7%) males and 41(37.3%) females. The clinical features of patients being observed by surgeons were recorded. Those were right iliac fosse pain, generalized abdominal pain, fever, loss of appetite and nausea. White blood cells count, C-reactive protein and general urine analysis were also studied, in addition to abdominal ultra-sonography and computer tomography (C.T.). The age group of both sexes being more susceptible for appendicitis ranged from 11 to 20 years old. The ratio of males to females' infections was 1.7:1. A total of 111 bacterial isolates were isolated from inflamed appendicitis of 110 patients with acute appendicitis. Positive bacterial cultures were detected in 90 (81.8%) patients while 20 (18.2%) patients showed no growth. The aerobic bacteria accounted for 87 (78.4%) isolates whereas anaerobic were only 24(21.6%) isolates. Gram-negative bacteria were presented in 107 (96.4%) while gram-positive bacteria were accounted for 4 (3.6%). Escherichia coli was the predominant pathogens, since it accounted for 36 (32.4%) of all isolates followed by Bacteroides spp. 21 (18.9%), Klebsiella pneumoniae 18 (16.2 % ), Pseudomonas aeruginosa 11 (9.9%), Citrobacter freundii 7 (6.3%), Salmonella typhi 5 (4.5%), Proteus mirabilis 5 (4.5%), Enterobacter aerogenesa 4 (3.6%), Peptodtreptococcus 2 (1.8%), Staphylococcus aureus 1 (0.9%) and Clostridium perfringns 1 (0.9%). Mixed cultures were detected in 21 cases*, in which more than one organism were detected. Most of mixed bacterial isolates were aerobic with anaerobic bacteria 13 (61.9%) in which Escherichia coli was the common, since it accounted for 15 (71.4%).
