Quantitative bacteriology-A predictor of risk of postoperative infection in open fractures Arthi K.1, Deepa R.2,*, Mangala A3 1Assistant Professor, Dept. of Microbiology, Meenakshi Ammal Dental College, Chennai, Tamil Nadu 2Associate Professor, Dept. of Microbiology, Government Villupuram Medical College, Tamil Nadu 3Director, Dept. of Microbiology, Madurai Medical College, Tamil Nadu, India *Corresponding Author: Email: arthikrao82@gmail.com
Online published on 14 January, 2019. Abstract Introduction Quantitative Microbiology involves measurement of an absolute quantity of bacteria per unit of volume. The threshold to distinguish colonisation from infection is 105 CFU/g. Quantitative cultures are used in predicting the risk of post operative infection. Aim To determine the role of quantitative bacteriology as a predictor of risk of infection in patients with open fractures. Materials and Methods One hundred patients who had sustained open fractures of long bones were included in the study. During debridement before antiseptic wash, a piece of tissue (muscle/skin) was collected under aseptic precautions for quantitative culture. A quantitative count of ≥ 104cfu/gm was interpreted as significant microbial burden. These patients were followed up for 6 weeks for development of clinical signs of infection and two swabs were collected by Levine's technique for semiquantitative culture. Results The preoperative culture of the debrided tissue of 41% yielded a microbial load of ≥104 cfu/gram among which 85.3% had 105 cfu/gram of microbial load. Polymicrobial growth was reported in 12.2% of patients. Postoperatively 39% developed signs of infection Seventy one percent of patients with 105 cfu/gram of microbial load in the preoperative period developed postoperative infection. All patients with polymicrobial growth in the preoperative debridement cultures with ≥104 cfu/gm of microbial load, developed infection in the postoperative period. Conclusion Quantitative Microbiology plays a precise role in predicting the risk of infection as it is valuable in estimating the bacterial bioburden. Polymicrobal etiology can lead to clinical infection if not managed effectively. Top Keywords Quantitative, Infection, Bioburden, Fracture, Debridement. Top |