Biofilm colonization in chronic treatment refractory infections presenting with discharging sinuses: A study in a tertiary care hospital of Eastern India

Abstract

INTRODUCTION:Treatment refractory chronic recurrent infections mean those chronic infections which recur by same causal agents with similar drug responsiveness after apparent relief following full course of recommended antimicrobial management.MATERIALS AND METHODS:Fifty different samples were collected from patients with chronic surgical site infections, laparoscopic port site infections, anal fistula, mesh hernioplasty, chronic dacryocystitis, chronic osteomyelitis, and chronic burn wounds. Samples were processed for culture, identification, antibiotic sensitivity testing using standard microbiological techniques. Biofilm (BF) forming capacity for aerobic organisms were tested by tissue culture plate method. Those for anaerobes and atypical mycobacteria were studied by a novel method using atomic force microscopy (AFM). In vivo BF colonization in lacrimal mucosae of chronic dacryocystitis, patients were studied from histopathological sections by Gram staining, H and E, and fluorescent in situ hybridization (FISH).RESULTS:Out of fifty different samples, sixty-three isolates were obtained in pure culture as follows: Staphylococcus aureus (25.39%), Escherichia coli (14.28%), Klebsiella pneumonia (14.28%), Mycobacterium abscessus (12.69%), Citrobacter spp. (9.52%), Bacteroides fragilis (6.3%), Pseudomonas aeruginosa (4.7%), Proteus spp. (4.7%), Staphylococcus epidermidis (3.1%), Enterobacter spp. (1.5%), Morganella morganii (1.5%), and Peptostreptococcus spp. (1.5%). Among the isolates, 74% were found to be BF producers in the following frequency: P. aeruginosa 100%, S. epidermidis 100%, B. fragilis 100%, Klebsiella spp. 88.88%, S. aureus 81.25%, M. abscessus 75%, Citrobacter spp. 83.33%, Proteus spp. 66.66%, E. coli spp. 33.33%, and Enterobacter spp. 0%.CONCLUSION:AFM has been proven to be a useful method for detection of in vitro grown BF including those for anaerobes and atypical Mycobacteria. In vivo BF detection becomes possible by FISH. S. aureus was the most common isolate. Among the aerobic isolates, P. aeruginosa and S. epidermidis were found to be the most common BF producers. Atypical mycobacteria were also found to be BF producers. Diagnosis of BF s in chronic infections significantly changes the management strategy as these infections can no longer be dealt simply with antibiotics alone but require mechanical removal of the foci along with antibiotic coverage for complete cure.

Role of biofilm-specific antibiotic resistance genes PA0756-0757, PA5033 and PA2070 inPseudomonas aeruginosa

“…The rate of biofilm-forming multi-drug resistant P. aeruginosa is increasing in India and the developing antibiotic-resistant biofilm forming P. aeruginosa is worrisome [14]. Recent studies showed that biofilm producing P. aeruginosa isolated from clinical samples were resistant to amikacin, imipenem, ciprofloxacin and gentamicin [14][15][16]. This study found that out of 24 strains of P. aeruginosa studied, 16 were biofilm producers and most of the biofilm forming strains were resistant to gentamicin and ciprofloxacin.…”

Relative Abundance and Detection of Pseudomonas aeruginosa from Chronic Wound Infections Globally

“…There were 30 studies conducted in Asian countries that discussed the microbiology of wound infections and the prevalence of P. aeruginosa ( Figure 1 ). Countries that were represented in the literature search included China [ 69 , 70 , 71 ], India [ 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ], Indonesia [ 83 , 84 ], Iran [ 85 , 86 ], Kuwait [ 87 ], Lebanon [ 88 ], Malaysia [ 89 , 90 , 91 ], Pakistan [ 92 , 93 , 94 ], Singapore [ 95 ], Turkey [ 96 ], and Iraq [ 97 ]. Most of the included studies focused on diabetic foot infections, and the frequency of P. aeruginosa isolation was therefore comparable when all chronic wound infections were evaluated or if diabetic foot infections specifically were analyzed ( Figure 1 and Figure 2 ).…”

“…Contrary to the rest of the continent, P. aeruginosa was the most abundant pathogen in India and Malaysia. Of the 11 studies that took place in India, five of the investigations found that P. aeruginosa was the most commonly isolated organism, which was followed by S. aureus and members of the order Enterobacterales (mainly Escherichia coli and Klebsiella pneumoniae ), respectively [ 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ]. The reported frequency of P. aeruginosa isolation was also relatively consistent with a range of 16–30% in every Indian study.…”

“…In addition to a lack of an association between P. aeruginosa and amputations, the presence of P. aeruginosa has failed to correlate with other clinically meaningful processes as well. Despite being associated with the production of biofilm in wound infections [ 55 , 81 ], P. aeruginosa was not associated with delayed wound healing in chronic leg ulcerations [ 58 ]. In a separate investigation, the lack of Pseudomonas species being detected from leg ulcerations was associated with delayed wound healing in a multivariate analysis ( p = 0.005) [ 108 ], but the specific impact of P. aeruginosa on wound healing may depend on the virulence factors possessed by each individual strain [ 70 ].…”

Physics Comes to the Aid of Medicine—Clinically-Relevant Microorganisms through the Eyes of Atomic Force Microscope

“…AFM was also used to detect biofilms formed by anaerobes and atypical mycobacteria isolated from hospital patients [ 139 ]. Recently, nanoresolution of the atomic force microscope and AFM-based morphological analysis was also reported to be useful in investigation of K. pneumoanie biofilms, notably by combining AFM with infrared (IR) spectroscopy and spectral imaging, which, overall, allowed for the collection of data on the composition and distribution of the chemical components of biofilm [ 140 ].…”