Antibiotic Treatment Regimens Research Articles

Efficacy and Tolerability of Antibiotic Combinations in Neurobrucellosis: Results of the Istanbul Study

No data on whether brucellar meningitis or meningoencephalitis can be treated with oral antibiotics or whether an intravenous extended-spectrum cephalosporin, namely, ceftriaxone, which does not accumulate in phagocytes, should be added to the regimen exist in the literature. The aim of a study conducted in Istanbul, Turkey, was to compare the efficacy and tolerability of ceftriaxone-based antibiotic treatment regimens with those of an oral treatment protocol in patients with these conditions. This retrospective study enrolled 215 adult patients in 28 health care institutions from four different countries. The first protocol (P1) comprised ceftriaxone, rifampin, and doxycycline. The second protocol (P2) consisted of trimethoprim-sulfamethoxazole, rifampin, and doxycycline. In the third protocol (P3), the patients started with P1 and transferred to P2 when ceftriaxone was stopped. The treatment period was shorter with the regimens which included ceftriaxone (4.40 ± 2.47 months in P1, 6.52 ± 4.15 months in P2, and 5.18 ± 2.27 months in P3) (P = 0.002). In seven patients, therapy was modified due to antibiotic side effects. When these cases were excluded, therapeutic failure did not differ significantly between ceftriaxone-based regimens (n = 5/166, 3.0%) and the oral therapy (n = 4/42, 9.5%) (P = 0.084). The efficacy of the ceftriaxone-based regimens was found to be better (n = 6/166 [3.6%] versus n = 6/42 [14.3%]; P = 0.017) when a composite negative outcome (CNO; relapse plus therapeutic failure) was considered. Accordingly, CNO was greatest in P2 (14.3%, n = 6/42) compared to P1 (2.6%, n = 3/117) and P3 (6.1%, n = 3/49) (P = 0.020). Seemingly, ceftriaxone-based regimens are more successful and require shorter therapy than the oral treatment protocol.

Development of a novel technique for axenic isolation and culture of thraustochytrids from New Zealand marine environments

To maintain axenic cultures of commercially important thraustochytrids, a novel procedure was developed for the isolation of zoospores and sporangium from heterotrophic seawater samples and axenic culture on solid media. Thraustochytrid cultures were isolated from Whangapoua Harbour in North East New Zealand and subjected to two antibiotic and antifungal treatment regimes designed to eliminate bacteria and fungi. Antibiotic trial 1 was designed to determine the appropriate combination of antibiotics (including streptomycin/penicillin, ampicillin, rifampicin, nalidixic acid, tetracycline, gentamicin and the antifungal agent nystatin). Antibiotic trial 2 determined the optimal dosing frequency and concentration of the antibiotics, and antifungal found to be the most promising in trial 1. Axenic cultures were then spread plated onto nutrient agar containing the optimal antibiotic cocktail, and pure thraustochytrid colonies were purified on solid media using standard microbiological techniques. Removal of bacteria and fungi was best accomplished using a mixture of three antibiotics and one antifungal; rifampicin (300 mg l(-1)), streptomycin/penicillin (25 mg l(-1)) and nystatin (10 mg l(-1)) were incorporated in seawater samples and incorporated into cultures every 24 h for a minimum of 2 days. The axenic isolation and culture of marine thraustochytrids from a marine habitat in New Zealand have significant implications for the biotechnological development of these potentially valuable protists. This method has global significance as it is reasonable to assume it could be used throughout the world to obtain axenic thraustochytrid cultures.

Selecting Against Antibiotic-Resistant Pathogens: Optimal Treatments in the Presence of Commensal Bacteria

Using optimal control theory as the basic theoretical tool, we investigate the efficacy of different antibiotic treatment protocols in the most exacting of circumstances, described as follows. Viewing a continuous culture device as a proxy for a much more complex host organism, we first inoculate the device with a single bacterial species and deem this the 'commensal' bacterium of our host. We then force the commensal to compete for a single carbon source with a rapidly evolving and fitter 'pathogenic bacterium', the latter so-named because we wish to use a bacteriostatic antibiotic to drive the pathogen toward low population densities. Constructing a mathematical model to mimic the biology, we do so in such a way that the commensal would be eventually excluded by the pathogen if no antibiotic treatment were given to the host or if the antibiotic were over-deployed. Indeed, in our model, all fixed-dose antibiotic treatment regimens will lead to the eventual loss of the commensal from the host proxy. Despite the obvious gravity of the situation for the commensal bacterium, we show by example that it is possible to design drug deployment protocols that support the commensal and reduce the pathogen load. This may be achieved by appropriately fluctuating the concentration of drug in the environment; a result that is to be anticipated from the theory optimal control where bang-bang solutions may be interpreted as intermittent periods of either maximal and minimal drug deployment. While such 'antibiotic pulsing' is near-optimal for a wide range of treatment objectives, we also use this model to evaluate the efficacy of different antibiotic usage strategies to show that dynamically changing antimicrobial therapies may be effective in clearing a bacterial infection even when every 'static monotherapy' fails.

Disseminated mycosis in a killer whale (Orcinus orca)

Hematological findings in a female killer whale (Orcinus orca) undergoing rehabilitation after sudden severe anorexia revealed continuing increases in serum lactate dehydrogenase and aspartate aminotransferase activities as well as fibrinogen concentration. Serologic evidence of herpesvirus infection and skin vesicles were detected 2 weeks into the treatment regimen of antibiotics and corticosteroids. The whale showed signs of improvement after treatment with anti-herpesvirus drugs, but sudden severe anorexia reappeared, along with marked elevation of fibrinogen concentration that continued until the death. Postmortem examination revealed multiple light tan foci of necrosis in the skeletal and cardiac muscles, and lung consolidation. Microscopic findings indicated disseminated fungal granulomas in the skeletal and cardiac muscles, as well as myocarditis, mycotic embolic thromboarteritis of cardiac blood vessels, and bronchopneumonia with numerous typical Aspergillus-like fungi. Mucor-like structures in granulomas in the heart and skeletal muscle and Aspergillus-like fungi in the lungs were identified using periodic acid-Schiff, Gomori methenamine silver stain, and immunohistochemistry. The present case involves dual infection with Mucor and Aspergillus species in a killer whale with concurrent herpesvirus.

Acute supraglottitis in adults in Finland: Review and analysis of 308 cases

The aim of this article is to study the clinical features, management, and outcome in adult patients with acute supraglottitis. Retrospective review. We searched the medical records from our database from the years 1989 to 2009 using codes of international statistical classification of diseases and related health problems for acute epiglottitis or supraglottitis. In total, 308 patients were identified. Incidence of acute supraglottitis increased from 1.88 (first decade) to 4.73 per 100,000 cases (second decade) (P = .05). The mean age of the patients was 49 years old with a slightly male predominance. Sore throat and odynophagia were the most common symptoms. Concomitant disease were common among the patients. Isolated inflammation of epiglottis without involvement of other supraglottic tissue was detected only in 51 patients. Intravenous cephalosporins were the most common empiric antibiotic treatment regimen. Intravenous corticosteroids were administered to half of the cases. Streptococcus was the most common organism in throat cultures. In total, 45 patients needed airway intervention. Complications were rare and mortality was 0.6% in our series. Acute supraglottitis in adults seems to be a different entity than epiglottitis in children, and inflammation does not usually exclusively involve the epiglottis. Early diagnosis seems to decrease the need for airway intervention and to permit the successful treatment of the patient with intravenous antibiotics and corticosteroids. Streptococcus appears as the dominant causative microorganism. However systemic diseases and other local infections that compromise the regional supraglottic immunity may increase the risk for acute supraglottitis.

Optimizing Antimicrobial Susceptibility Test Reporting

ABSTRACT A meeting of clinical microbiologists, representing a diverse group of practice settings, together with representatives from industry partners, discussed the pitfalls of current practices for testing and reporting antimicrobial susceptibility test results. The participants in this session identified several needs. Regarding what antibiotics to test, the discussants noted that the CLSI M100 documents must be readily accessible to all those who need them and presented in a way that is easily understood. Engineering controls (e.g., software programs) are needed that incorporate intrinsic resistance and susceptibility information and contain pathways that would allow the reporting of antibiotics for only those body locations where the antibiotic reaches therapeutic concentrations. These programs should be linked with the patient electronic medical record (EMR) and flag the physician or clinical pharmacist using an active alert messenger when testing reveals that the antibiotic(s) that the patient is receiving may not be optimal or de-escalation of the antibiotic treatment regimen is indicated. Guidelines for the practice of cascade reporting are needed and should be developed to assist laboratories in the identification and reporting of therapeutic and cost-effective antimicrobials. Personalized antibiotic reporting (PAR) software programs are needed that would deduce the optimal antibiotic for each individual patient based on a number of clinical and laboratory features. These would include the following: (i) organism identification; (ii) MIC; (iii) patient-specific factors such as weight, immune status, allergies, creatinine clearance, and albumin level; (iv) site of infection; (v) desired method of dosing (bolus versus continuous infusion); (vi) patient convenience (oral versus intravenous); (vii) drug interactions; and (viii) cost.

Treatment protocol and relapses of brucella endocarditis; cotrimoxazole in combination with the treatment of brucella endocarditis

Antibiotic treatment, surgical intervention and postoperative antibiotic regimens are recommended for the treatment of brucella endocarditis (BE). Our clinical antibiotic regimens involve a triple antibiotic regimen for treating BE before the operation. The combination of three antibiotics is continued for at least six months and until the titres of the Wright serologic test are diminished to 1:160 levels. In this study, our aim was to evaluate the effects of combined medical and surgical treatments on survival and relapse rates in the periods of mid to late terms. We investigated 13 patients who were treated between January 1993 and June 2009. Our clinical observations led us to use a combination of rifampicin (900 mg twice a day), streptomycin (12 to 16 mg/kg/24 h intramuscularly) and doxycycline (200 mg/kg twice a day); rifampicin, tetracycline (8 mg/kg three times a day) and cotrimoxazole (15 mg/kg twice a day) or rifampicin, doxycycline and cotrimoxazole regimen for treating BE before the operation. This treatment should be continued for at least six months after surgery in order to prevent relapses.

Cholera epidemic in and around kolkata, India: endemicity and management.

Cholera epidemic in and around kolkata, India: endemicity and management.

A new in vivo method to investigate antibiotic penetration and concentration in spontaneous infectious spondylodiscitis

Spontaneous discitis is unusual and typically affects children. Hematogenous delivery of an infectious organism is the likely main cause. Common treatment method including conservative and surgical treatments, which also needs prolonged antimicrobial therapy based on an effective inhibitory concentration, can be achieved on the local disc space. Intradiscal antibiotic concentration was measured after the disc was harvested after preventive administration of antibiotics in previous studies. On the one hand the disc cannot simulate the infection situation when the inflammation leads to end plate destruction, vascular invasion and increase of permeability. On the other hand antibiotic concentrations were measured in vitro which cannot tell the actual situation in vivo. It is necessary to find a reliable evaluation method to decide whether the antibiotic can penetrate and make an effective inhibitory concentration in the local disc at the beginning of the treatment in vivo. Systemic antibiotics like nutrients enter and leave the disc by the only way of passive diffusion. The postcontrast MRI has been widely used as a noninvasive method of studying transport into the disc. The enhancement following contrast administration can be measured in T1 sagittal MR images by placing suitable cursors and evaluating the signal intensity (SI) of the region. Therefore we hypothesise that serial postcontrast MRI can be used to measure antibiotic concentration in the infected intervertebral disc in vivo. If the hypothesis is verified, we can better determine the choice of antibiotics and antibiotic treatment regime at the beginning of the treatment to improve the treatment success rate.

Filariasis in Africa—treatment challenges and prospects

Lymphatic filariasis (LF) and onchocerciasis are parasitic nematode infections that are responsible for a major disease burden in the African continent. Disease symptoms are induced by the immune reactions of the host, with lymphoedema and hydrocoele in LF, and dermatitis and ocular inflammation in onchocerciasis. Wuchereria bancrofti and Onchocerca volvulus, the species causing LF and onchocerciasis in Africa, live in mutual symbiosis with Wolbachia endobacteria, which cause a major part of the inflammation leading to symptoms and are antibiotic targets for treatment. The standard microfilaricidal drugs ivermectin and albendazole are used in mass drug administration programmes, with the aim of interrupting transmission, with a consequent reduction in the burden of infection and, in some situations, leading to regional elimination of LF and onchocerciasis. Co-endemicity of Loa loa with W. bancrofti or O. volvulus is an impediment to mass drug administration with ivermectin and albendazole, owing to the risk of encephalopathy being encountered upon administration of ivermectin. Research into new treatment options is exploring several improved delivery strategies for the classic drugs or new antibiotic treatment regimens for anti-wolbachial chemotherapy.

Múltiples abscesos cerebrales por Listeria monocitogenes en un paciente con infección por el virus de inmunodeficiencia humana, primer caso descrito en Colombia

The manifestations of Listeria monocytogenes central nervous system infection are wide, ranging from meningitis to cerebral abscesses. Those are clinically indistinguishable from other forms of cerebral abscesses. We are describing a HIV positive woman who presented with generalized tonicclonic seizures, progressive alter mental status, evidence of lymphocytic pleocytosis and multiple hypodense lesions that enhanced with contrastae on imaging studies (CT and MRI) Listeria monocytogenes was isolated of cefaloraquid liquid cultures. After a specific antibiotic treatment regimen associated with steroids, improved neurological symptoms and concomitant documented a progressive decrease until disappearance of the lesions in the CNS imaging follow. Listeria monocytogenes is a cause of brain abscesses in immunosuppressed patients especially HIV patients without antiretroviral therapy and without prophylaxis with trimethoprim / sulfamethoxazole.

Antibiotic therapy for acute Q fever in The Netherlands in 2007 and 2008 and its relation to hospitalization

Data about the effectiveness of different antibiotic regimens for the treatment of acute Q fever from clinical studies is scarce. We analysed the antibiotic treatment regimens of acute Q fever patients in 2007 and 2008 in The Netherlands and assessed whether hospitalization after a minimum of 2 days antibiotic therapy was related to the initial antibiotic therapy. Clinical data on antibiotic treatment and risk factors of acute Q fever patients were obtained from general practitioner medical records and self-reported by patients. For the 438 study patients, doxycycline was the most commonly prescribed initial antibiotic in both study years. After adjustments for confounding factors, doxycycline (200 mg/day), moxifloxacin, as well as other possibly effective antibiotics [including other new fluoroquinolones and doxycycline (100 mg/day)] showed significant lower risks for hospitalization compared to β-lactam antibiotics and azithromycin (reference group), with the lowest risk for doxycycline (200 mg/day) (odds ratio 0·04, 95% confidence interval 0·01-0·22). These data support current guidelines that recommend doxycycline as the first choice antibiotic for treating acute Q fever.

Nanobead-based interventions for the treatment and prevention of tuberculosis

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is one of the most devastating bacterial diseases to affect humans. M. tuberculosis is a robust pathogen that has evolved the capacity to survive and grow inside macrophage phagosomes. A cocktail of antibiotics has long been successfully used against M. tuberculosis but is becoming less effective owing to the emergence of multidrug resistance. The only available preventive vaccine, using Mycobacterium bovis bacille Calmette-Guérin, is considered to be ineffective against adult pulmonary TB, the most prevalent form of the disease. Here, we review the potential use of biodegradable nanoparticle-based anti-TB drug delivery systems that have been shown to be more effective against M. tuberculosis in animal models than conventional antibiotic treatment regimens. This technology also has substantial potential for vaccination and other therapeutic strategies against TB and other infectious diseases.

Different antibiotic regimens for treating asymptomatic bacteriuria in pregnancy.

Asymptomatic bacteriuria occurs in 5% to 10% of pregnancies and, if left untreated, can lead to serious complications. To assess which antibiotic is most effective and least harmful as initial treatment for asymptomatic bacteriuria in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2010) and reference lists of retrieved studies. Randomized controlled trials comparing two antibiotic regimens for treating asymptomatic bacteriuria. Review authors independently screened the studies for inclusion and extracted data. We included five studies involving 1140 women with asymptomatic bacteriuria. We did not perform meta-analysis; each trial examined different antibiotic regimens and so we were not able to pool results. In a study comparing a single dose of fosfomycin trometamol 3 g with a five-day course of cefuroxime, there was no significant difference in persistent infection (risk ratio (RR) 1.36, 95% confidence interval (CI) 0.24 to 7.75), shift to other antibiotics (RR 0.08, 95% CI 0.00 to 1.45), or in allergy or pruritus (RR 2.73, 95% CI 0.11 to 65.24). A comparison of seven-day courses of 400 mg pivmecillinam versus 500 mg ampicillin, both given four times daily, showed no significant difference in persistent infection at two weeks or recurrent infection, but there was an increase in vomiting (RR 4.57, 95% CI 1.40 to 14.90) and women were more likely to stop treatment early with pivmecillinam (RR 8.82, 95% CI 1.16 to 66.95). When cephalexin 1 g versus Miraxid(R) (pivmecillinam 200 mg and pivampicillin 250 mg) were given twice-daily for three days, there was no significant difference in persistent or recurrent infection. A one- versus seven-day course of nitrofurantoin resulted in more persistent infection with the shorter course (RR 1.76, 95% CI 1.29 to 2.40), but no significant difference in symptomatic infection at two weeks, nausea, or preterm birth. Comparing cycloserine with sulphadimidine, no significant differences in symptomatic, persistent, or recurrent infections were noted. We cannot draw any definite conclusion on the most effective and safest antibiotic regimen for the initial treatment of asymptomatic bacteriuria in pregnancy. One study showed advantages with a longer course of nitrofurantoin, and another showed better tolerability with ampicillin compared with pivmecillinam; otherwise, there was no significant difference demonstrated between groups treated with different antibiotics. Given this lack of conclusive evidence, it may be useful for clinicians to consider factors such as cost, local availability and side effects in the selection of the best treatment option.

Impact of different empirical antibiotic treatment regimens for community-acquired pneumonia on the emergence of Clostridium difficile

Treatment of community-acquired pneumonia (CAP) with newer fluoroquinolones may contribute to selection for Clostridium difficile. We studied the prevalence of C. difficile carriage and C. difficile infection (CDI) on admission, and nosocomial acquisition rates in patients hospitalized for CAP and compared different empirical treatment strategies. In a prospective study among patients admitted for antibiotic treatment of CAP, consecutive stool and skin samples were collected and cultured for C. difficile. Cultured isolates were typed by PCR ribotyping and characterized for toxinogenicity. In total, 20 of 107 (18.7%) patients included carried C. difficile. Various ribotypes were found and 14 (70%) isolates were toxinogenic. On admission, prevalence of C. difficile carriage was 9.4% (n=9), of which 22% also carried C. difficile on the skin and one patient had mild CDI with persistent positive cultures. The overall nosocomial acquisition rate of C. difficile carriage was 11.2%. No nosocomially acquired CDI occurred. Acquisition rates of C. difficile were 11.9% (5/45) in moxifloxacin-, 11.1% (5/47) in β-lactam- and 9.0% (1/14) in β-lactam plus macrolide- or fluoroquinolone-treated patients (P=0.84). Risk factors for C. difficile carriage were intravenous antibiotic treatment >7 days [odds ratio (OR) 3.89; 95% confidence interval (CI) 1.30 to 11.79] and hospitalization during the past 3 months (OR 4.08; 95% CI 1.40 to 11.90). In a non-outbreak setting with a low endemic rate, the prevalence of C. difficile carriage in patients admitted because of CAP is high and nosocomial acquisition rates for C. difficile colonization are 11%. Fluoroquinolones were not associated with increased acquisition rates for C. difficile as compared with other empirical regimens for CAP.

Localized Melioidosis in Children in Thailand: Treatment and Long-term Outcome

Melioidosis, an infection caused by Burkholderia pseudomallei, can present as severe septicemia or localized infection. Data on optimum antibiotic treatment regimen for localized melioidosis in children is limited. This is a report on localized melioidosis in children, regarding clinical presentation, treatment and the long-term outcomes. We reviewed 37 cases of localized melioidosis in children treated between 1994 and 2006 and followed up them prospectively until 1 October 2007. The two most common presentations were skin/soft tissue infections and suppurative parotitis. Oral eradication antibiotics after initial parenteral therapy included trimetroprim-sulfamethoxazole (10 patients) and trimetroprim-sulfamethoxazole in combination with doxycycline (four patients). Patients who did not get any parenteral antibiotics for B. pseudomallei were treated with oral trimetroprim-sulfamethoxazole (10 patients) and trimetroprim-sulfamethoxazole in combination with doxycycline (one patient). No adverse effects were reported. We were able to follow-up 32 patients, all recovered except one patient reported a history of possible relapse.

A Four-week-old Infant With an Intracardiac Mass

A Four-week-old Infant With an Intracardiac Mass

Poster Board Number: 87: Severe Odontogenic Infections: Predictors for Successful Treatment and a Comparison of 2 Antibiotic Treatment Regimens

Statement of the Problem: Depending on the demographics of a specific hospital, deep space infections of odontogenic origin that require hospitalization can be treated by variable specialty practitioners. Recent reports in the medical literature support the empiric use of wide-spectrum antibiotics, leading to issues with over-usage of antibiotics, which leads to increased bacterial resistance. Additionally, there is no consensus between practitioners as to the use of laboratory and radiographic investigations to direct the duration of inpatient hospitalization for these patients.

Diagnosis and Management of Bacterial Vaginosis and Other Types of Abnormal Vaginal Bacterial Flora: A Review

Bacterial vaginosis (BV) is a common cause of abnormal vaginal discharge. It is characterised by an overgrowth of predominantly anaerobic organisms (Gardnerella vaginalis, Prevotella spp., Peptostreptocci, Mobiluncus spp.) in the vagina leading to a replacement of lactobacilli and an increase in vaginal pH. BV can arise and remit spontaneously, but often presents as a chronic or recurrent disease. BV is found most often in women of childbearing age, but may also be encountered in menopausal women, and is rather rare in children. The clinical and microscopic features and diagnosis of BV are herein reviewed, and antibiotic and non-antibiotic treatment approaches discussed. Obstetricians & Gynecologists, Family Physicians. After completion of this educational activity, the participant should be better able to analyze bacterial vaginosis clinically, formulate an oral antibiotic treatment regimen for bacterial vaginosis and use vaginal treatments for bacterial vaginosis.

Acute Lobar Nephronia Is Associated With a High Incidence of Renal Scarring in Childhood Urinary Tract Infections

Acute lobar nephronia (ALN) is a severe nonliquefactive inflammatory renal bacterial infection, and requires a longer duration of treatment. The aim of this prospective study was to investigate renal scarring after ALN and to examine the risk factors for renal scarring in children with ALN compared with those with acute pyelonephritis (APN). Patients with computed tomography-diagnosed ALN were enrolled and randomly allocated, with serial entry, to either a 2- or 3-week antibiotic treatment regimen. Age- and gender-matched APN patients served as comparators. Patients underwent dimercaptosuccinic acid scintigraphy at least 6 months later to assess renal scarring. A total of 218 children (109 ALN, 109 APN) were enrolled. The incidence of renal scarring was similar between 2- and 3-week treatment groups and was higher in ALN patients than in APN patients (89.0% vs. 34.9%, P < 0.001). Renal scarring was prone to occur in children with higher inflammatory indices and longer duration of fever before and after treatment. Multiple regression analysis on independent variables showed that only ALN was significantly associated with a higher incidence of renal scarring. Our results showed a new finding that ALN is associated with a very high incidence of renal scarring, in comparison to APN, irrespective of the duration of antibiotic treatment.