https://imcjms.com/public Ibrahim Medical College Journal of Medical Science https://imcjms.com/public/registration/journal_full_text/141 Wed, 09 Nov 2016 15:33:36 +0000 Identification of organisms and effective antibiotic therapy is an important component of treatment of diabetic foot infections. This study was undertaken to determine the organisms associated with diabetic foot infection (DFI) and their antibiotic sensitivity pattern. A total of 75 patients having type 2 diabetes mellitus with Wagner’s grade 1-5 foot ulcers attending BIRDEM hospital were included in the study. Specimens were processed for aerobic culture. The bacteriological isolation and antimicrobial sensitivity tests of the isolates were done by standard microbiological methods. Gram negative bacilli were tested for extended spectrum b lactamase (ESBL) production by double disc diffusion method. Culture was positive in 92% of the cases which yielded 135 pathogens. Of the positive culture, 75.3% had multiple organisms. Polymicrobial infection was more in higher grade of foot ulcers. Gram negative organisms were most frequently isolated (80%) bacteria. Pseudomonas (48%) and Proteus sp.(33%) was the most common Gram negative organisms isolated. Staphylococcus aureus was the most commonly isolated gram positive organism (21.3%). ESBL production was noted in 31.5% Gram negative bacilli and methicillin resistance was noted in 43.8% of Staphylococcus aureus. Most of the Gram negative bacilli were resistant to various classes of antibiotics. Imepenem was the most effective agent against Gram negative organisms, while vancomycin was for staphylococcus. The present study has shown that infection with multidrug resistant Gram negative bacilli is the most common cause of DFI in BIRDEM hospital. Ibrahim Med. Coll. J. 2009; 3(2): 50-54 Introduction A good outcome of DFI depends upon being familiar with the microbiological profile of the infection that can help in selecting the most appropriate antimicrobial therapy.13 This study was conducted with an aim to attempt determining the microbiological and microbial susceptibility profile of organisms isolated from diabetic foot ulcers of patients attending BIRDEM hospital. Methods Seventy five diabetic patients with clinically infected foot ulcers attending both Surgery and Orthopedics outpatient and inpatient departments at BIRDEM hospital during the period of June 2008 to October 2008 were studied.   Fig-1: Different grades of diabetic foot ulcers: A- Grade 0, B- Grade 1, C- Grade 2, D- Grade 3, E- Grade 4, F- Grade-5. Grade 0- Preulcer. No open lesions, skin intact; may have deformities, erythemetous areas of pressure or hyperkeratosis. Grade 2- Full thickness ulcer. Penetrates through fat to tendon, or joint capsule without deep abscess or osteomyelitis. Grade 4- Denotes gangrene of a geographical portion of the foot such as toes, forefoot or heel. The remainder of the foot is salvageable though it may be infected.   Culture specimens were obtained after the surface of the wound had been washed vigorously by saline and followed by debridement of superficial exudates. The materials used were curettage of the base of the ulcer, needle aspiration of the abscess material and deep wound swab. Microbiological methods   The clinical characteristics of 75 study population are shown in Table 1. Males were predominant (69.3%) and the mean age of the patients was 52.8 ± 11.7 years. All of them were suffering from type 2 diabetes mellitus (T2DM) and the duration of diabetes ranged between 3-20 years. Among them, 25 (33.3%) had neuropathy and 18 (24%) had peripheral vascular disease. The majority (53.3%) had infected foot ulcer for >1 month and 50 (66.7%) of them had prior antibiotic intake while more than two thirds (70.7%) received surgical treatment prior to admission into BIRDEM hospital. The foot ulcers fell into all the grades (1-5), the most common being grade 3 ulcers (36%). Table-1: Clinical features of 75 diabetic patients with infected foot ulcer       Table 3 shows the frequency of isolation of different organisms from diabetic foot ulcers. Gram negative organisms were most frequently isolated (80%) followed by Gram positive (19.3%) and fungus (0.7%). Pseudomonas species (36 isolates) was isolated from 48% cases and accounted for one third of all isolates. Other organisms were Proteus sp (33.3%), Klebsiella sp (28%), Esch. coli ((14.7%), Acinetobacter sp (6.6%), Citrobacter sp (5.3%), Serratia sp (1.3%) and Providencia sp (1.3%). S. aureus was the most common Gram positive organism and accounted for 21.3% of the infections. Table-3: Rate of isolation of organism from foot ulcers       Table-5: Rate of isolation of ESBL producing Gram negative bacilli and ulcer infection rate with ESBL and MRSA   Our study was designed to detect the bacteria responsible for diabetic foot infections among patients attending the out and in-patient departments of BIRDEM hospital. Most of our patients had grade 3 ulcers. Our study shows that in chronic, complex and previously treated wounds, infections are generally polymicrobial with mixed Gram positive and Gram negative organisms. We found Gram negative aerobic bacteria as the most frequently isolated organism though previous studies had shown Gram positive aerobes as the predominant organisms in DFI.9,14,18,19 Thus the major infective organisms in diabetic foot ulcer in our patients appear to be different. The ratio of Gram positive to Gram negative was 1:4. The differences in the age-sex composition and ulcer grades between our study population and those of earlier studies might be the reason for these differences. However, our results are in tune with other studies done in India which also showed that Gram negative bacteria were the most predominant organisms in DFI.10,11 The role of anaerobic organisms in DFI could not be determined as no attempt was made in this study to isolate the anaerobes.   We thank the staff of Department of Surgery and Orthopedics, BIRDEM hospital for their contribution in sample collection. References 2.   Khan MH. Pathogenesis of diabetic foot ulcer. Diab Endocr J 2006; 34(suppl 1): 11. 4.   Saleh F, Ahmed KR, Rashid IB, Akter F, Hannan JMA, Ali L, Rahman M, Mannan S, Thilsted S. Evaluation of the levels of knowledge, attitude and practices of Bangladeshi Type 2 Diabetic subjects. Diab Endocr J 2005; 33(1): 24-27. 6.   Dang CN, Prasad YD, Boulton A.J., Jude EB. Methicillin resistant Staphylococcus aureus in the diabetic foot clinic: a worsening problem. Diabet Med 2003; 20: 159-161. 8.   Lipsky BA, Pecoraro SA, Larson M, Hanley E, Ahroni JH. Outpatient management of uncomplicated lower extremity infections in diabetic patients, Arch Intern Med 1990; 150: 790-797. 10.Gadepalli R, Dhawan B, Sreenivas V, Kapil A, Ammini AC, Chaudhry R. A Clinico-microbiological study of diabetic foot ulcers in an Indian tertiary care hospital. Diabetes Care 2006; 29(8): 1727-1732. 12.Lipsky BA, Pecoraro RE, Wheat JL. The diabetic foot: soft tissue and bone infection. Infect Dis Clin North Am 1990; 4(3): 409-432. 14.Sharma VK, Khadka PB, Joshi A, Sharma R. Common pathogens isolated in diabetic foot infection in Bir Hospital. Katmandu University Medical Journal 2006; 4(3): 295-301. 16.Emery CL, Weymouth LA. Detection and clinical significance of extended spectrum b-lactamases in a tertiary-care medical center. J Clin Microbiol 1997: 2061-67. 18.Yoga R, Khairul A, Sunita K, Suresh C. Bacteriology of diabetic foot lesions. Med J Malaysia 2006; 61(suppl A); 14-6. 2026 Ibrahim Medical College. All rights reserved.