Aetiology of catheter-associated bacteriuria in Lagos University Teaching Hospital.

A prospective study to determine the causative agents of catheter-related bacteriuria was carried out on 99 patients with median age of 55 years, on admission in the Oncology, Paediatric Surgery and Obstetric and Gynaecology wards of the Lagos University Teaching Hospital. There was significant bacteriuria in seventy-one (72%) of the 99 urine samples. All catheter urine samples were contaminated by day 5 Gram-negative bacilli were predominant (89.3%) of which Pseudomonas aeruginosa (26.2%) was the most common, while Escherichia coli and Enterobacter aerogenes accounted for 15.5% each, closely followed by Proteus mirabilis (14.3%) and Klebsiella pneumoniae (9.5%). The Gram positive isolates Enterococcus faecalis (8.3%) and Staphylococcus saprophyticus (2.4%) made up only 10.7% of isolates. Most of the isolates from catheterised patients were resistant to the common antibiotics such as ampicillin, cotrimoxazole, gentamicin and ceftriaxone with high susceptibility to ofloxacin and ceftazidime though the isolates of Enterococcus faecalis was also resistant to ofloxacin. However, isolates of S. saprophyticus were still susceptible to the penicillins and tetracycline.