Antimicrobial Medication Research Articles

Comparison of pyogenic spondylitis and tuberculous spondylitis.

Pyogenic spondylitis and tuberculous spondylitis are common causes of spinal infection. It is difficult to differentiate tuberculous spondylitis and pyogenic spondylitis clinically and radiologically. Recently magnetic resonance imaging has been reported to be beneficial for early diagnosis and differential diagnosis of the spondylitis, and is being used extensively for diagnosis. However, the diagnosis must be considered in combination with corresponding changes in clinical manifestations, radiological findings, blood and tissue cultures and histopathological findings. Conservative treatments, including antimicrobial medications, are started initially. Surgical treatments, which include anterior or posterior approach, single-stage or two-stage surgery, with or without instrumentation, may be performed as indicated.

Clinical examination, diagnostic testing, and treatment options for neonatal calves with diarrhea

Primary diarrhea and septicemia are the 2 most common disease syndromes in neonatal calves. Differentiating between the 2 is difficult but vital, in order to determine prognosis and appropriate treatment. Both syndromes generally present with watery diarrhea, acidbase derangements, and/or negative energy balance. Depressed mentation and recumbency can occur with either disease if acidosis, hypoglycemia, hypokalemia, or dehydration is severe. In this review, we discuss criteria that distinguish primary diarrhea from diarrhea secondary to septicemia and present guidelines for the assessment, care, and management of diarrheic calves. Physical examination is the single-most powerful tool in differentiating the syndromes in individual calves. Therefore, particular emphasis is placed on the assessment of the calf's demeanor, including mentation and suckling ability, its ability to stand, and the presence or absence of systemic infection. The value of laboratory diagnostics that assess acid-base and hydration status, and the adequacy of passive transfer are described. Strategies for fluid and electrolyte therapy and the use of antimicrobial, anti-inflammatory, and anticonvulsant medications are also discussed. Whether aggressive diagnostic techniques and therapeutic interventions are employed depends on the value of the individual animal and the case prognosis. This review provides the basis for optimal decision-making, thus ensuring that optimal care is provided for the calf while meeting the goals of the owner.

Antibiotic stewardship in Germany: a cross-sectional questionnaire survey of 355 intensive care units

Little information is available on antibiotic prescription management in German hospitals. The objective of this cross-sectional study was to determine the prevalence and components of antibiotic stewardship measures in German intensive care units (ICUs). A questionnaire survey was sent to all ICUs participating in the German nosocomial infection surveillance system (n = 579) in October 2011. Data on antibiotic management structures were collected and analyzed by structural hospital and ICU factors. The questionnaire was completed by 355 German ICUs (response rate 61 %). Common measures used (>80 % of the ICUs) were personnel restrictions for antibiotic prescriptions, routine access to bacterial resistance data, and pharmacy reports on antibiotic costs and consumption. A small proportion of ICUs (14 %) employed physicians specialized in the prescription of antimicrobial medication. Hospitals with their own microbiological laboratory report participation in surveillance networks for antimicrobial use (34 %) and bacterial resistance (32 %) twice as often as hospitals with external laboratories (15 and 14 %, respectively, p < 0.001). Also, non-profit and public hospitals participate more often in surveillance networks for bacterial resistance than private hospitals (>23 % vs. 11 %, p < 0.05). While the majority of ICUs report to have some antibiotic policies established, the contents and composition of these policies vary. Organizational-level control strategies to improve antibiotic management are common in Germany. However, strategies widely considered effective, such as the systematic cross-institutional surveillance of antimicrobial use and bacterial resistance in a standardized manner or the employment of infectious disease specialists, are scarce. This study provides a benchmark for future antibiotic stewardship programs.

Calcium Antagonists: A Ready Prescription for Treating Infectious Diseases?

Emergence of new and medically resistant pathogenic microbes continues to escalate toward worldwide public health, wild habitat, and commercial crop and livestock catastrophes. Attempts at solving this problem with sophisticated modern biotechnologies, such as smart vaccines and microbicidal and microbistatic drugs that precisely target parasitic bacteria, fungi, and protozoa, remain promising without major clinical and industrial successes. However, discovery of a more immediate, broad spectrum prophylaxis beyond conventional epidemiological approaches might take no longer than the time required to fill a prescription at your neighborhood pharmacy. Findings from a growing body of research suggest calcium antagonists, long approved and marketed for various human cardiovascular and neurological indications, may produce safe, efficacious antimicrobial effects. As a general category of drugs, calcium antagonists include compounds that disrupt passage of Ca(2+) molecules across cell membranes and walls, sequestration and mobilization of free intracellular Ca(2+), and downstream binding proteins and sensors of Ca(2+)-dependent regulatory pathways important for proper cell function. Administration of calcium antagonists alone at current therapeutically relevant doses and schedules, or with synergistic compounds and additional antimicrobial medications, figures to enhance host immunoprotection by directly altering pathogen infection sequences, life cycles, homeostasis, antibiotic tolerances, and numerous other infective, survival, and reproductive processes. Short of being miracle drugs, calcium antagonists are welcome old drugs with new tricks capable of controlling some of the most virulent and pervasive global infectious diseases of plants, animals, and humans, including Chagas' disease, malaria, and tuberculosis.

Structural and Functional Integrity of Spermatozoa Is Compromised as a Consequence of Acute Uropathogenic E. coli-Associated Epididymitis1

Uropathogenic Escherichia coli (UPEC)-associated epididymitis is commonly diagnosed in outpatient settings. Although the infection can be successfully cleared using antimicrobial medications, 40% of patients unexplainably show persistent impaired semen parameters even after treatment. Our aim was to investigate whether pathogenic UPEC and its associated virulence factor hemolysin (hlyA) perturb the structural and functional integrity of both the epididymis and sperm, actions that may be responsible for the observed impairment and possibly a reduction of fertilization capabilities. Semen collected from patients diagnosed with E. coli-only related epididymitis showed that sperm counts were low 14 days postantimicrobial treatment regardless of hlyA status. At Day 84 following treatment, hlyA production correlated with approximately 4-fold lower sperm concentrations than in men with hlyA-negative strains. In vivo experiments with the hlyA-producing UPEC CFT073 strain in a murine epididymitis model showed that just 3 days postinfection, structural damage to the epididymis (epithelial damage, leukocyte infiltration, and edema formation) was present. This was more severe in UPEC CFT073 compared to nonpathogenic E. coli (NPEC 470) infection. Moreover, pathogenic UPEC strains prematurely activated the acrosome in vivo and in vitro. Raman microspectroscopy revealed that UPEC CFT073 undermined sperm integrity by inducing nuclear DNA damage. Consistent with these observations, the in vitro fertilization capability of hlyA-treated mouse sperm was completely abolished, although sperm were motile. These findings provide new insights into understanding the possible processes underlying clinical manifestations of acute epididymitis.

Effectiveness of Artocarpus lakoocha extract, poloxamer 407, on Enterococcus faecalis in vitro

The antiviral activities of Artocarpus lakoocha (A.lakoocha) extract have been reported in a number of studies; however, data regarding its antibacterial capability are limited. The aim of the present study was to examine the effectiveness of A.lakoocha extract, poloxamer 407, on Enterococcus faecalis (E.faecalis). The effect of the antimicrobial activity of A.lakoocha extract and A.lakoocha extract, poloxamer 407, against E.faecalis was investigated. The antibacterial efficacy of A.lakoocha extract, poloxamer 407, against E.faecalis was compared to calcium hydroxide in a tooth model. The minimal inhibitory concentration and minimal bactericidal concentration (MBC) of A.lakoocha extract against E.faecalis were 0.39±0mg/mL and 3.12±0mg/mL, respectively; the MBC of calcium hydroxide against E.faecalis was 31.25±0mg/mL. In the tooth model, the E.faecalis count in all groups significantly decreased as the depth into the dentin increased compared to the control. There were no significant differences between 4% A.lakoocha extract poloxamer and UltraCal XS at any time period (P>0.05) with one exception: at a depth of 0.6mm on day 5, UltraCal XS had a significantly greater colonization than 4% A.lakoocha extract poloxamer. A.lakoocha extract, poloxamer 407, might be a useful alternative for antimicrobial medication in endodontic treatment. However, controlled clinical studies to evaluate its efficacy are needed.

Evaluating the impact of a pharmacist’s absence from an antimicrobial stewardship team

Results of a study to determine the impact of a clinical pharmacist's temporary absence from a hospital's antimicrobial stewardship team are presented. A retrospective chart review was conducted to compare the appropriateness of the use of selected antimicrobial medications with and without regular pharmacist involvement on the hospital's antimicrobial stewardship team. The charts of two samples of patients were evaluated: (1) 119 patients who had received prolonged (≥72 hours) imipenem-cilastatin, linezolid, or micafungin therapy over a three-month period during which a clinical pharmacist routinely provided interventions to help ensure the drugs were used according to institutional guidelines and (2) 111 patients treated with one of the three drugs during a three-month period when the clinical pharmacist did not serve on the stewardship team. Relative to the period of active pharmacist involvement in antimicrobial stewardship, rates of inappropriate use of imipenem-cilastatin, linezolid, and micafungin during the pharmacist's absence were deemed to have increased by 27, 39, and 35 percentage points, respectively, with corresponding increases in the average duration of therapy of 0.7, 4.0, and 3.2 days; in addition, the number of cases of Clostridium difficile infection increased more than threefold (from 8 to 25) during the pharmacist's absence. The temporary absence of a pharmacist from the antimicrobial stewardship team was associated with increased rates of inappropriate use of restricted antimicrobial agents and consequent increases in average durations of therapy.

P096: Antibiotic stewardship in intensive care units: a cross sectional study of 355 ICUs in Germany

Results The questionnaire was completed by 355 German ICUs (61% response rate). The most common measures used (>80% of the ICUs) were personal restrictions for antibiotic prescriptions, routine access to unit-based bacterial resistance data and pharmacy reports on antibiotic costs and consumption. A small proportion of ICUs (14%) employed ABS consultants or infectious diseases specialists for the prescription of antimicrobial medication. Hospitals with their own integrated microbiological laboratory report twice as much to take part in surveillance networks of antimicrobial use (34%) and bacterial resistance (32%) compared with hospitals with external laboratories (15% and 14%, respectively, p 23% vs. 11%, p<0.05). Conclusion While the majority of ICUs report to have some antibiotic policies established, the contents and composition of these strategies vary markedly. Organizational-leveled control strategies to improve antibiotic control are already quite common in Germany. In contrast, other strategies widely considered effective such as the continuous surveillance of antimicrobial use and bacterial resistance or the employment of infectious disease consultants are still scarce. More effort is required with regard to incentives for infectious diseases consultants and to the participation in surveillance networks. This study provides a benchmark for future antibiotic stewardship programs.

THU0338 Incidence of selected opportunistic infections among children with juvenile idiopathic arthritis

BackgroundThere may be an increased risk of opportunistic infections among children with juvenile idiopathic arthritis (JIA), especially with exposure to immunosuppressant medications. No controlled studies to address this question have...

Knowledge and attitude towards antimicrobial self medication usage: a cross sectional study among medical and nursing students

Background: Antimicrobial drug resistance is a fast mounting universal crisis. Many factors like self medication, inappropriate use and unregulated sale of medicines and self medication have been attributed to this problem. The objective was to determine extend and causes of antimicrobial self medication and to compare the knowledge attitude of senior and junior medical/nursing students. Methods: We conducted a cross-sectional study on randomly selected 410 students from Baba Farid University of Health Sciences Faridkot, Punjab. A total sample of 220 medical students were enrolled from GGS Medical College, Faridkot (1 st year students 50 and 170 above 1 st year senior medical students ) and 190 nursing students were enrolled from University College of Nursing, Faridkot. Results: prevalence of antimicrobial self medication came out to be around 74%. The most common cause for seeking antimicrobial (self therapy) was upper respiratory tract infection. A statistical significant knowledge/attitude gap was found between senior and fresher medical/nursing students. Conclusions: High prevalence of antimicrobial self medication among medical/nursing students is a matter of concern and it should be discouraged at appropriate level to safeguard students from preventable adversary exposure.

Prevention of adverse drug events and cost savings associated with PharmD interventions in an academic Level I trauma center

The financial benefit of an established clinical pharmacy service in the trauma intensive care unit has not been well-described. This study was conducted to identify adverse drug events prevented by the clinical pharmacy team and to determine the net cost savings associated with their input on a multidisciplinary trauma service. Between July 2010 and June 2011, we conducted a retrospective analysis of clinical pharmacy activities and interventions on our 31-bed trauma unit managed by a multidisciplinary team. At the initiation of the study, a Web-based pharmacy documentation system was officially integrated into the trauma pharmacy work process. Based on this system, the type of intervention and a value of cost savings ($0-$6,000) were assigned to each activity. Cost-saving values for interventions were calculated from the literature describing the costs of adverse drug events and average drug costs. Over the year, a total of 2,574 pharmacy activity entries were documented in the Quantifi system. The total conservative estimate of cost savings associated with clinical pharmacy interventions amounted to $565,664. Considering the mean US hospital pharmacist salary and the highest quoted cost associated with the Quantifi program, the net cost savings associated with our clinical pharmacist interventions on the trauma service was $428,327. Most of the interventions (53%) fell under the category of pharmacotherapy improvement, with 21% in the category of quality/safety improvement and 18% as antibiotic stewardship. Prevention of 34 serious adverse drug events was documented. Antibiotic changes and discontinuing medications were other common interventions. Antimicrobial medications (668), anticoagulants (270), and gastrointestinal medications (231) were the most common medication classes involved in pharmacy interventions. Using a Web-based pharmacy documentation system, we were able to demonstrate prevention of serious adverse drug events and a significant cost savings by including clinical pharmacy in a multidisciplinary approach to caring for the seriously injured. Economic analysis, level III; therapeutic study, level IV.

Personalised medicine in exacerbations of COPD: the beginnings

Exacerbations of chronic obstructive pulmonary disease (COPD) are inflammatory events induced by infection [1]. Therefore, the use of antimicrobial and anti-inflammatory medications in exacerbations appears logical. However, the evidence that antibiotics and corticosteroids are beneficial in the treatment of exacerbations is relatively sparse, and only a meta-analytic approach has given us sufficient confidence in the use of these treatments [2, 3]. Placebo-controlled and observational studies in hospitalised patients with COPD exacerbations have shown the benefit of antibiotics and steroids [4–6]. This has led to current recommendations for treating all hospitalised exacerbations with both antibiotics and steroids. However, as we appreciate the heterogeneity of infection and inflammation in exacerbations, using the same treatment in all exacerbations does not appear appropriate. Bacterial infection causes approximately 50% of exacerbations; therefore, antibiotic use is probably unnecessary in the other 50% [1]. Eosinophilic inflammation is seen in a third of exacerbations, so corticosteroids may be of limited benefit in a substantial proportion of exacerbations [7]. In a hospitalised patient with a COPD exacerbation, the cost of antibiotics accounts for a small fraction of the total cost of care. However, everyone is well aware of the dangers of inappropriate and excessive antibiotic use with regards to selection of antibiotic resistant pathogens and adverse effects. Therefore, discriminating exacerbations that are bacterial in origin from those that are not would help us target antibiotic therapy. Sputum cultures lack the sensitivity, specificity and speed to be such a discriminatory tool. Biomarkers such as …

Elution of antimicrobials from a cross‐linked dextran gel:In vivoQuantification

Use of a novel, biodegradable, antimicrobial-impregnated gel provides an alternative method of local treatment of infections in horses. To determine in vivo elution of antimicrobial medications from antimicrobial-impregnated cross-linked dextran gel and to evaluate the effect on wound healing when implanted subcutaneously in horses. Amikacin-, vancomycin- or amikacin/clindamycin-impregnated gel was placed subcutaneously in 11 horses' necks, using 6 replicates with a 3 month washout between experiments. Capillary ultrafiltration probes for collection of interstitial fluid were placed 0 cm and 1.5 cm from the gel-filled incisions. Samples were collected at 0, 4, 8 and 12 h, and on Days 1-10. Blood was collected on Days 0, 1 and 7. Amikacin and vancomycin samples were analysed via fluorescence polarisation immunoassay, and clindamycin samples via high-performance liquid chromatography. Histology of biopsy samples was performed at the completion of the study. Differences in mean histomorphological scores between groups were assessed using Wilcoxon's signed ranks test. Maximum antimicrobial concentrations were detected at 4 h (amikacin), and 8 h (vancomycin, and amikacin and clindamycin from the combination gel). Mean ± s.d. peak concentrations for amikacin, vancomycin, amikacin (amikacin/clindamycin) and clindamycin were 6133 ± 1461, 7286 ± 2769, 3948 ± 317 and 985 ± 960, respectively. Median number of days for which antimicrobial concentration remained above minimum inhibitory concentration for target microorganisms at implantation was ≥10 days for vancomycin, 9 days (± 1) for amikacin and 8 days (± 1) for clindamycin. Mean plasma amikacin and vancomycin concentrations were lower than detectable limits; mean serum clindamycin concentrations were 0.52 µg/ml and 0.63 µg/ml at 24 h and 7 days, respectively. There were no significant differences in histomorphological scores between treatment and control incisions (P≥0.22). Cross-linked dextran gel is a safe, effective alternative local antimicrobial delivery method.

The Association of Serum Neutrophil Markers and Acute Coronary Syndrome

An association exists between chronic infection-induced inflammation, such as periodontitis, and acute coronary syndrome (ACS). We studied the association of serum neutrophil markers, myeloperoxidase (MPO), matrix metalloproteinase (MMP)-8, tissue inhibitor of metalloproteinase (TIMP)-1 concentrations and MMP-8/TIMP-1 ratio, with the risk of recurrent ACS. Radiographic periodontal status was recorded from 141 patients with acute non-Q-wave infarction or unstable angina pectoris, who participated in a double-blind, placebo-controlled study with clarithromycin for 3 months. Serum samples were collected within arrival to the hospital, at 1 week, 3 months and 1 year. Recurrent ACS events were registered during the 1-year follow-up. In the whole population, high serum MPO concentrations at 1 week (fourth quartile versus quartiles 1-3) were associated with the risk of recurrent ACS with a relative risk (RR) of 2.52 (95% CI, 1.277-4.980; P = 0.008). In patients without periodontal disease, high MPO concentration at 1 week and 1 year predicted recurrent ACS with RRs of 3.54 (1.600-7.831; P = 0.002) and 2.87 (1.171-7.038; P = 0.021), respectively. In the placebo group, but not in the clarithromycin group, high serum MMP-8/TIMP-1 ratio at 1 week predicted recurrent ACS with an RR of 3.23 (1.295-8.063; P = 0.012). Our results suggest that high serum neutrophil markers reflect increased risk of recurrent ACS, especially in patients without periodontal disease and not receiving antimicrobial medication.

Brugada Syndrome Unmasked by Febrile Illness in an Asymptomatic Child

4-year-old boy was admitted to the hospital for fever, cough, and chest pain in the last 2 days. Chest radiograph showed pneumonia of the lower left lobe, and antimicrobial medication was administered. Of note, an electrocardiogram (ECG) was performed while the patient had a fever, which revealed coved ST-segment elevation >2 mm in right precordial V1-V2 leads and incomplete right bundlebranch block, compatible with type 1 Brugada syndrome pattern (Figure). This ECG pattern disappeared as the patient’s fever subsided. Echocardiogram excluded structural anomalies. Family history revealed sudden death in a maternal 9-month-old sister and a 5-month-old cousin; no episodes of syncope or arrhythmia were referred. The whole family was screened for Brugada syndrome, and his mother resulted positive. Genetic analysis in the child excluded SCN5A gene mutations. No long-term treatment was started because the patient was asymptomatic and at low risk for sudden death, given his asymptomatic Brugada syndrome ECGpatternduringfeverandhisnegativehistoryforsyncope. Brugada syndrome accounts for 20% of sudden death in young adults, with a prevalence in children of 3 per 10000. 1 Brugada syndrome is inherited in an autosomal-dominant manner 2 and is attributable to cardiac sodium channel muta

Comparative Assessment of Antimicrobial Usage Measures in the Department of Veterans Affairs

We compared 2 data sources--antimicrobial orders and bar-coded medication administration (BCMA)--for calculating the number of grams used, grams used based on defined daily dose, and days of therapy at one Veterans Affairs Medical Center for 2009-2010. The number of grams used calculated from BCMA data provided the most informative antimicrobial utilization measure.

A questionnaire survey of poultry layer farmers in Khartoum State, Sudan, to study their antimicrobial awareness and usage patterns

An initial census of layer farms in Khartoum State, Sudan, was carried out in late 2007 and early 2008 and found that there were 252 layer farms with a total population of 2 221 800 birds. This paper reports the findings of the census. Based on this information, a structured questionnaire survey of 92 farms was then conducted in the state in April 2008 to collect data on antibiotic usage, demographic data and public health awareness. Ninety-eight per cent of participating farms comprised open-sided houses. It was found that 49% of the farms surveyed were on antibiotic treatment when the survey was conducted, whilst 59% of the farms had used antibiotics within the last 3 months. The study found that farmers and producers had a lack of knowledge about antimicrobial residues, their withdrawal periods and the risk posed by the consumption of these residues. The study also concluded that traditional farming systems in Sudan relied heavily on antimicrobial medication to control disease and almost half of the farms surveyed were treating their flocks with antimicrobials. In addition to this, there was a lack of disease control programmes which probably resulted in a massive use of antibiotics to control endemic diseases. This was further compounded by the absence of governmental supervision and control on the use of drugs.

The effect of Lactobacillus casei and Bifidobacterium breve on antibiotic-associated diarrhea treatment: randomized double-blind clinical trial

Antibiotic-associated diarrhea (AAD) is an important side effect of this specific class of drugs. The objective of this study was to investigate the effect of the use of probiotics in the treatment of AAD. A group of hospitalized patients, who contracted diarrhea during or after 7 days of suspension of antimicrobial medication, was blindly randomized to receive a standardized diet associated with the use of the probiotics (Lactobacillus casei and Bifidobacterium breve) or its corresponding placebo, three times a day. Seventy patients were studied. For the experimental (n=35) and control (n=35) groups, respectively, the average time of treatment was 5.06±2.18 and 5.49±3.17 days (p=0.95), and the average duration of diarrhea, among those who were healed, was 4.87±2.13 and 4.52±2.55 days (p=0.36). Four (11.4%) patients who received probiotics and ten (28.6%) who received the placebo were not cured (p=0.13), and relapse rates were similar between both groups. Seven patients from each group, in addition to diarrhea, presented cases of bloating and/or abdominal cramps and/or vomiting (p=1.00). In this light, it is concluded that L. casei associated with B. breve, in the administered dosage and frequency, has no effect on the antibiotic-associated diarrhea. Similar studies need to be conducted with higher doses of these or other probiotics.

Osteomyelitis of the Patella in Eight Foals

To describe the characteristics of osteomyelitis lesions of the patella and to report short- and long-term outcome after treatment in 8 foals. Retrospective case series. Foals (n = 8). Medical records (2003-2007) and radiographs of foals that had osteomyelitis of the patella were reviewed. Inclusion criteria included clinical, radiographic, and surgical findings consistent with osteomyelitis of the patella, and a long-term follow-up of >15 months. Information acquired included signalment, hematologic and serum biochemical profile results, clinical and radiographic signs, surgical technique and perioperative treatment. Follow-up radiographs were evaluated and outcome was determined from veterinary examination, race records, and telephone questionnaire. Six foals survived long term (15 months-4 years); all had intralesional and systemic antimicrobial therapy, along with synovial lavage and antimicrobial medication. All were sound and achieved either yearling sales (n=3), show hunter or racing (2). Two foals died in the short term from renal failure and suppurative peritonitis secondary to cecal perforation, 1 remaining lame with suppurative osteonecrosis confirmed at necropsy. This foal was not administered intralesional antimicrobial therapy. Prompt medical and surgical therapy for osteomyelitis of the patella can result in a good prognosis for soundness and a potential athletic career. Concurrent septicemia or other systemic perinatal disease can result in prolonged therapy and delayed recovery.

Development of an intracanal mature Enterococcus faecalis biofilm and its susceptibility to some antimicrobial intracanal medications; an in vitro study

To develop a mature biofilm of Enterococcus faecalis inside the root canal system and to test its susceptibility to some antimicrobial medications in vitro. Single rooted premolars were mechanically enlarged, sterilized, and then infected with a clinical isolate of E. faecalis. Biofilm formation and maturation was monitored using SEM. Biofilm bacteria were exposed to Amoxicillin+clavulanate, Ciprofloxacin, Clindamycin, Doxycycline, and calcium hydroxide as intracanal medications for 1 week. Finally bacterial samples were collected, and colony-forming units were enumerated. SEM examination confirmed the formation of a mature biofilm at the end of the incubation period. All the chemotherapeutic agents used were significantly better than Calcium hydroxide in elimination of biofilm bacteria. The antimicrobial effect of Amoxicillin + clavulanate, Ciprofloxacin and Clindamycin was significantly better than Doxycycline (P=.05). However the difference in the antimicrobial effectiveness among them was statistically non-significant (P=.05). The method used for bacterial biofilm development and maturation is reliable and can be used to assess the anti bacterial potential of endodontic materials. Also, the local application of antibacterial agents can be beneficial in resistant cases of apical periodontitis but only after careful culture and sensitivity testing to choose the appropriate agent for the existing flora.