Empirical Drug Therapy Research Articles

Drug resistance pattern, prevalence and risk factors for resistance to second line anti-tuberculosis drugs in Balochistan, Pakistan

Background. Pakistan is high burden drug resistant tuberculosis (DR-TB) country. For devising a treatment regimen and optimizing empirical drug therapy, the local epidemiology and drug resistance patterns are needed to be considered. Objectives. To evaluate the drug resistance pattern, prevalence and risk factors for resistance to second line anti-tuberculosis drugs (SLD) among DR-TB patients in Balochistan, Pakistan. Design and setting. This cross-sectional study was carried out at the Fatimah Jinnah Chest and General Hospital in Quetta's programmatic management unit of the DR-TB (PMDT). Methods. This study included all DR-TB patients, regardless of their age, TB location, or medication resistance pattern. The sociodemographic, microbiological, and clinical data of the patients were gathered using a standard data collecting form. SPSS 20 was used to analyze the data. A statistically significant p-value was defined as less than 0.05. Results. A total of 354 patients were included in the final analysis. Among them majority were females (61.7%), belonged to the age group 19-30 years (36.7%), were previously treated for TB (95.8%) at public sector hospital (42.7%) and did not suffer from any other comorbidity(88.7%). The study participants were resistant to a median of three anti-TB drugs (range 1-8). The most common type of DR-TB was multi DR-TB (77.1%), followed by mono DR-TB (18.1%), extensive DR-TB(3.1%) and poly-DR (1.7%). A total of 147 (41.5%) patients were resistant to any second line anti-TB drug (SLD). Among SLD, the resistance was high for fluoroquinolones (38.4%), followed by ethionamide (4.8%) and injectable SLD(4.2%). Upon multivariate binary logistic regression analysis previous treatment of cat-II regimen had statistical significant association with resistance to any SLD (OR=5.273, 95%CI=1.098-25.316). Conclusion. It is concerning to see such a high level of SLD resistance, especially to fluoroquinolones. More stringent regulations are advised to regulate the non-prescription sale and indiscriminate use of fluoroquinolones, as well as testing for drug resistance in cat-I failures instead of placing patients on cat-II therapy.

Insight into the Burden of Antimicrobial Resistance among Bacterial Pathogens Isolated from Patients Admitted in ICUs of a Tertiary Care Hospital in India.

Intensive care unit (ICU) patients are prone to develop infections by hospital prevalent organisms. The aim of the study was to determine the bacteriological profiles and their drug resistance pattern among different infections in ICU patients of a tertiary care hospital. The record-based retrospective data of culture reports of the patients admitted to all the ICUs of a tertiary care hospital during the period from January 2020 to May 2022 were analyzed. A total of 3,056 samples were obtained from 2308 patients. The infection rate among ICU patients was found to be 53.40%. Isolates belonged equally to males (50.86%) and females (49.14%). The most common culture-positive clinical specimen received was blood (39.08%) followed by respiratory samples (29.45%). Acinetobacter sp. (33.02%) was the most common organism isolated from various clinical specimens, followed by Klebsiella pneumoniae (20.89%), and Escherichia coli (13.8%). More than 80% of Acinetobacter species were found to be resistant to third-generation cephalosporins, aminoglycosides, and carbapenems, whereas minocycline (56.31% S) and colistin (100% S) were the most effective drugs. Klebsiella sp. was found to be more resistant than E.coli, and the least resistance was observed to be tetracycline (43.97%) and doxycycline (55.84%). Among Staphylococcus aureus, 82.78% of strains were methicillin-resistant (MRSA). Vancomycin-resistant Enterococci (VRE) sp. accounted for 16.67% of the isolates. Evidence-based knowledge regarding the local bacterial organisms and their antimicrobial resistance pattern is pivotal in deciding empirical drug therapy, ultimately leading to the management of antimicrobial resistance (AMR).

Worrisome Implications of Accidental Injection of Colourless Corrosive Chemicals Intraorally into Perioral Tissue Spaces: A Severe Negligence

During certain treatment procedures in a dental clinic, few colourless chemicals like Local Anaesthetics (LA), sodium hypochlorite, formalin, hydrogen peroxide, xylene, chloroform, etc., are often used simultaneously. Instead of LA, these chemicals may be accidentally injected in oral soft tissues due to casual handling. These accidental injections produce severe corrosive effects in and around perioral tissues and may lead to chemical necrotising cellulitis within 24 hours. Osteolytic changes of underlying bone and fatty infiltration with necrosis of the soft tissues can also occur. These events of accidental injection of such corrosive chemical solutions in patients during dental treatment may occur owing to the use of empty LA bottles for storage of these corrosive chemicals which can be easily mistaken for LA solution. Every solution has its indicated use in dentistry and treatment procedure. While performing any treatment procedure in dental clinic, utmost care and precautions must be taken to avoid any medical negligence in administering such corrosive chemicals intraorally which may make the patient’s life havoc because of hazardous complications in maxillofacial region. This paper reviews accidental intraoral injection of these colourless chemicals and also discusses the adverse effects, prevention and management of such inadvertent injections. Successful management includes cautious debridement and empirical drug therapy (antibiotics and analgesics).

Bacteriological Profile and Antibiotic Susceptibility Pattern of Isolates of Wound Infection In Children Visiting Kanti Children Hospital

Objectives: The objectives of this study was to isolate and identify the bacterial etiological agent of wound infection and explore the status of methicillin-resistant Staphylococcus aureus ( MRSA), multidrug Resistant (MDR) and extended spectrum β-lactamase (ESBL) producers’ strains in clinical specimens and to find the antibiotic susceptibility pattern.
 Methods: A prospective cross sectional study design was conducted from period of February 2014 to October 2014 at Kanti Children Hospital, Kathmandu. The organisms were isolated and identified from pus sample by standard microbiological methods. Antimicrobial susceptibility test was performed by modified the Kirby Bauer disc diffusion method to evaluate the status of MRSA and MDR. ESBL detection was performed by the combined disc diffusion method.
 Results: Out of 365 specimens collected between the age group below < 2 to 15 years, 210 (57.73%) samples from male patients and 155 (42.47%) from female patients. In the total samples processed, Gram-positive organisms were found to be more prevalent in which Staphylococcus aureus accounts for 135(47.20%), followed by P. aeruginosa 62 (21.67%), E. coli 29 (10.20%), K. pneumoniae 27 (9.44%), Acinetobacter spp. 20 (6.70%), P. vulgaris 7 (2.44%) and CoNS 6 (2.10%). Among the S. aureus isolates, 29 (21.48%) were found MRSA. Of the total Gram-negative organisms isolated, 74 (51.03%) were MDR and 14 (100%) ESBL producer, (P<0.01). S. aureus was found to be the most important and leading cause of wound infection in this study.
 Conclusion: Thus, routine antibiotic susceptibility testing is recommended for empirical drug therapy and proper management of disease.

The Febrile Infant: Where Art Meets Science to Prevent Harm.

1. Mobeen H. Rathore, MD, CPE* 1. *Editorial Board Member, Pediatrics in Review > With a nod (tongue in cheek) to the author’s previously published title (1) > One consistent thought continues to hold true when it comes to assessing the febrile infant. Be suspicious. > > —JZ, HDA Perhaps Dr Arnold Smith put it most eloquently: “Sorting out the child at risk, from those with illness that is not a threat to their health, is a fundamental goal of pediatrics” (Fig 1). (2) What Dr Smith wrote 40 years ago is true even today. Fever continues to be one of the most common ailments in children. Although fever is a friend of the patient, infection is a foe. Identifying the foe is a complicated task for the evaluating physician. This is even more challenging in infants and especially neonates because of less-than-optimal history, mostly unreliable examination, and more specific signs of infection in the neonates often appearing later in the disease course. Even a thorough laboratory evaluation is not always helpful. Ultimately it is the selection of optimum broad spectrum empirical antibiotic drug therapy that is really the most important decision to protect neonates from the serious morbidity and mortality of neonatal sepsis. Fortunately, most infections in children, including in neonates, are viral and self-limited, causing no serious morbidity. Unfortunately, rarely, bacterial infections can be serious and sometimes life-threatening. Herein lies the challenge even for the most experienced and knowledgeable …

Pathogens and drug susceptibility test of septic arthritis of hip in children

Objective To study the pathogens and their drug susceptibility of septic arthritis of hip in children. Methods Prior to the antibiotic treatment, pus was extracted for bacterial culture under aseptic operation. The pathogenic bacterium was identified and drug susceptibility was analyzed using a fully automated bacterial identification/drug susceptibility system. Results A total of 68 pathogens were isolated, in which 42 were Gram-positive bacteria, 23 were Gram-negative bacteria and 3 were fungi. The results showed differences in the bacterial types of hip septic arthritis in children with different ages (5 days to 13 years). For newborns (less than 1 month), the most common pathogen was Klebsiella pneumoniae; for the ages of 1 month to 13 years old, the most common pathogen was Staphylococcus aureus. The results of drug susceptibility tests showed that Gram-positive bacteria were highly susceptible to vancomycin, teicoplanin and linezolid; the resistance of Staphylococcus aureus to penicillin was up to 96%; and Klebsiella pneumoniae, Escherichia coli, Haemophilus influenzae, Enterobacter cloacae and Salmonella were highly sensitive to meropenem and imipenem. Conclusion In the antimicrobial drug treatment of children with hip septic arthritis, the etiology sample should be collected for drug susceptibility analysis. Empirical drug therapy strategy should be applied in the absence of the analysis results. Sensitive antibiotic drug therapy should be used after obtaining reliable etiological diagnosis and drug susceptibility results, and simultaneously taking the age into consideration. Key words: Children; Hip joint; Septic arthritis; Drug resistance; Antibiotic; Drug susceptibility test

Antiarrhythmic therapy as an adjuvant to promote post pulmonary vein isolation success-a meta-analysis.

Three months of empirical antiarrhythmic drug (AAD) therapy after atrial fibrillation ablation (AFA) is a common practice to prevent early arrhythmia recurrence; the data of influence of this practice on longer term ablation outcomes is limited. The aim of this study was to perform a meta-analysis of published controlled trials comparing temporary AAD therapy after AFA with no AAD therapy in patients after AFA. The primary outcome was recurrence of arrhythmia. 1Eight prospective trials were included. Among 2952 patients, 1991 (67%) had paroxysmal AF, and 967 (32.7%) had persistent AF. In total, 1502 patients were treated with AADs and 1450 patients served as a control group (no AAD therapy). Various class IC-III antiarrhythmics were used. Length of AAD administration varied between 6 and 12weeks after start of AFA. The follow-up duration ranged from 1.5 to 17months after stopping medication. Among AAD treated patients, the recurrence of arrhythmia rate was 30.69 vs. 33.79% in control patients (odd ratio 0.86, 95% CI 0.71-1.06, P = 0.15). In patients who received largely amiodarone, there was a trend for difference in recurrence of atrial arrhythmia (odds ratio 0.60, 95% CI 0.34-1.09, P = 0.09). Short-term post pulmonary vein isolation (PVI) AAD therapy does not substantially reduce overall recurrence of AF after ablation.

ANTIARRHYTHMIC THERAPY POST-ABLATION TO REDUCE ATRIAL FIBRILLATION RECURRENCE: A META-ANALYSIS

Three months of empirical antiarrhythmic drug (AAD) therapy after atrial fibrillation ablation (AFA) is a common practice to prevent early AF recurrence. There is limited data on the influence of this temporary post ablation AAD therapy on long term outcomes of the AFA. To perform a meta-analysis of published controlled trials comparing temporary AAD therapy peri- AFA with standard care in patients after AFA. The primary outcome was recurrence of arrhythmia. Seven prospective trials were included. Among 919 patients, 615 (67 %) had paroxysmal AF. In total, 489 patients were treated with AADs and 422 patients served as a control group (no AA therapy). Various class IC-III antiarrhythmics were used. Length of AAD administration varied between 6 to 12 weeks following AFA. The follow-up duration ranged from 1.5 to 17 months. Among AAD treated patients, the recurrence of arrhythmia rate was 36 % vs. 43 % in control patients (odd ratio 0.75, 95% CI 0.50-1.12, P=0.16). Evaluating patients who received Amiodarone only in the peri-AFA, we noted no difference in recurrence of atrial arrhythmia in comparison to control group (odds ratio 0.66, 95% CI 0.32-1.35, P=0.26). Temporary AAD therapy following AFA does not affect intermediate term arrhythmia recurrence rate.

Management of ventricular arrhythmias in suspected channelopathies.

Although structural heart disease remains the predominant substrate for ventricular arrhythmia, channelopathies including long QT syndrome (LQTS), short QT syndrome (SQTS), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and early repolarization syndrome (ERS) are less common but important contributing entities. These etiologies require specific therapies potentially contrary to empirical management of arrhythmias associated with structural heart disease. Conventional therapy including antiarrhythmic drug therapy may not only fail to resolve unstable arrhythmias but worsen them. Additionally, channelopathy patients with implantable cardioverter defibrillators (ICD) and arrhythmic storms represent a major challenge, and the acute care team needs to be cognizant of unique circumstances that require specific acute therapies beyond empirical advanced life support algorithm recommendations.1 Successful and considered acute management of ventricular arrhythmias is contingent on a number of variables, including knowledge of the cardiac substrate or potential substrate; form, mechanism, and precipitants of ventricular arrhythmias; and acute effect of potential therapies. In the longer term, an understanding of the natural history of the channelopathy along with the efficacy of long-term therapy will lead to superior outcomes. This review will present the risk of ventricular arrhythmias associated with these uncommon entities, the evolving understanding of the mechanism of arrhythmia, and the mechanistic basis of therapies along with a clinical approach to summarize the evidence pertaining to acute and long-term management. Patients with a prolonged QT interval are at risk of sudden cardiac death (SCD) due to Torsade de Pointes (TdP; Figure 1). Most patients with congenital LQTS are asymptomatic and diagnosed incidentally on electrocardiogram screening or following family screening. However, syncope, aborted SCD, or SCD may be the first presentation. Most arrhythmic events in congenital LQT1 occur during physical or emotional stress, at rest or in association with sudden auditory stimulation in LQT2, and during sleep or rest in LQT3 …

Answer to the topic "management of pyogenic discitis".

Sir/Madam, We thank Beuy Joob for commenting on our recent report on Surgical Management of Pyogenic Discitis of Lumbar Region [1]. We were able to get 100% culture positivity in the 42 cases probably because of open surgical extensive debridement of the disc space during posterior lumbar interbody fusion. Discitis due to tuberculosis (TB) and other causes were excluded, and only those that are managed surgically were included. The clinically and histopathologically confirmed TB discitis were not included. We also did histopathological analysis of the infected materials in all cases, which showed evidence of acute infection without granuloma formation. Obtaining proper representative sample for culture is of paramount importance in getting positive result. In case of culture negativity, simultaneous histopathological analysis of the material could help the clinician in differentiating pyogenic discitis from tuberculous discitis by the absence of granuloma. So, the tissue specimens should be subjected to histological analysis as well. It is even more important in tropical regions to diagnose and treat pyogenic discitis from TB, to avoid the major complications due to long term empirical anti-tuberculous drug therapy.

The use of classification and regression trees to predict the likelihood of seasonal influenza

Individual signs and symptoms are of limited value for the diagnosis of influenza. To develop a decision tree for the diagnosis of influenza based on a classification and regression tree (CART) analysis. Data from two previous similar cohort studies were assembled into a single dataset. The data were randomly divided into a development set (70%) and a validation set (30%). We used CART analysis to develop three models that maximize the number of patients who do not require diagnostic testing prior to treatment decisions. The validation set was used to evaluate overfitting of the model to the training set. Model 1 has seven terminal nodes based on temperature, the onset of symptoms and the presence of chills, cough and myalgia. Model 2 was a simpler tree with only two splits based on temperature and the presence of chills. Model 3 was developed with temperature as a dichotomous variable (≥38°C) and had only two splits based on the presence of fever and myalgia. The area under the receiver operating characteristic curves (AUROCC) for the development and validation sets, respectively, were 0.82 and 0.80 for Model 1, 0.75 and 0.76 for Model 2 and 0.76 and 0.77 for Model 3. Model 2 classified 67% of patients in the validation group into a high- or low-risk group compared with only 38% for Model 1 and 54% for Model 3. A simple decision tree (Model 2) classified two-thirds of patients as low or high risk and had an AUROCC of 0.76. After further validation in an independent population, this CART model could support clinical decision making regarding influenza, with low-risk patients requiring no further evaluation for influenza and high-risk patients being candidates for empiric symptomatic or drug therapy.

Endocarditis Caused by Actinobaculum schaalii, Austria

Endocarditis Caused by Actinobaculum schaalii, Austria

Difficult treatment decisions in autoimmune hepatitis

Treatment decisions in autoimmune hepatitis are complicated by the diversity of its clinical presentations, uncertainties about its natural history, evolving opinions regarding treatment end points, varied nature of refractory disease, and plethora of alternative immunosuppressive agents. The goals of this article are to review the difficult treatment decisions and to provide the bases for making sound therapeutic judgments. The English literature on the treatment problems in autoimmune hepatitis were identified by Medline search up to October 2009 and 32 years of personal experience. Autoimmune hepatitis may have an acute severe presentation, mild inflammatory activity, lack autoantibodies, exhibit atypical histological changes (centrilobular zone 3 necrosis or bile duct injury), or have variant features reminiscent of another disease (overlap syndrome). Corticosteroid therapy must be instituted early, applied despite the absence of symptoms, or modified in an individualized fashion. Pursuit of normal liver tests and tissue is the ideal treatment end point, but this objective must be tempered against the risk of side effects. Relapse after treatment withdrawal requires long-term maintenance therapy, preferably with azathioprine. Treatment failure or an incomplete response warrants salvage therapy that can include conventional medications in modified dose or empirical therapies with calcineurin inhibitors or mycophenolate mofetil. Liver transplantation supersedes empirical drug therapy in decompensated patients. Elderly and pregnant patients warrant treatment modifications. Difficult treatment decisions in autoimmune hepatitis can be simplified by recognizing its diverse manifestations and individualizing treatment, pursuing realistic goals, applying appropriate salvage regimens, and identifying problematic patients early.

Pneumonia Caused byShigella sonneiin Man Returned from India

Pneumonia Caused by<i>Shigella sonnei</i>in Man Returned from India

Antiarrhythmics After Ablation of Atrial Fibrillation (5A Study)

Atrial arrhythmias are common early after atrial fibrillation (AF) ablation. We hypothesized that empirical antiarrhythmic drug (AAD) therapy for 6 weeks after AF ablation would reduce the occurrence of atrial arrhythmias. We randomized consecutive patients with paroxysmal AF undergoing ablation to empirical antiarrhythmic therapy (AAD group) or no antiarrhythmic therapy (no-AAD group) for the first 6 weeks after ablation. In the no-AAD group, only atrioventricular nodal blocking agents were prescribed. All patients wore a transtelephonic monitor for 4 weeks after discharge and were reevaluated at 6 weeks. The primary end point of the study was a composite of (1) atrial arrhythmias lasting more than 24 hours; (2) atrial arrhythmias associated with severe symptoms requiring hospital admission, cardioversion, or initiation/change of antiarrhythmic drug therapy; and (3) intolerance to antiarrhythmic agent requiring drug cessation. Of 110 enrolled patients (age 55+/-9 years, 71% male), 53 were randomized to AAD and 57 to no-AAD. There was no difference in baseline characteristics between groups. During the 6 weeks after ablation, fewer patients reached the primary end point in the AAD compared with the no-AAD group (19% versus 42%; P=0.005). There remained fewer events in the AAD group (13% versus 28%; P=0.05) when only end points of AF >24 hours, arrhythmia-related hospitalization, or electrical cardioversion were compared. AAD treatment during the first 6 weeks after AF ablation is well tolerated and reduces the incidence of clinically significant atrial arrhythmias and need for cardioversion/hospitalization for arrhythmia management.

SegniliparusrugosusInfection, Australia

To the Editor: Recently, a female teenager with cystic fibrosis who resided in tropical north Queensland, Australia, was found to be infected with Segniliparus rugosus. She was homozygous for the deltaF508 mutation, had well-preserved lung function, and regularly played competitive sports. Unlike many cystic fibrosis patients, she did not have a history of chronic Pseudomonas aeruginosa infections, but Stenotrophomonas maltophilia and Achromobacter xylosoxidans had been previously isolated from her sputum. In May 2007, she described reduced exercise tolerance and increased cough with excess sputum production. Lung function testing showed modest spirometric decline. A computed tomographic scan of the chest showed significant mucus plugging and bronchiectasis, uncommon without previous P. aeruginosa infection. Sputum was 3+ smear positive for acid-fast bacilli (AFB), and S. rugosus was isolated from liquid culture. Empiric antimicrobial drug therapy was changed to rifabutin and co-trimoxazole because these drugs have been effective in previous cases (1). Clinically, the patient showed response to the treatment. After 12 months of treatment, her sputum was still 3+ positive for AFB, and S. rugosus was again found in culture. She was referred to a pediatric teaching hospital in Brisbane with worsening respiratory symptoms precipitated by influenza B infection. Antimicrobial drug therapy with intravenous imipenem, oral moxifloxacin, and co-trimoxazole for 2 weeks resulted in clinical improvement but little reduction in smear positivity. The initial AFB smear-positive sputum specimen underwent routine decontamination with sodium hydroxide and neutralization and was inoculated into radiometric 12B vials (Becton Dickinson, Sparks, MD, USA). The culture was positive after 6 days’ incubation and was referred to the state reference laboratory in Brisbane. The culture was smeared and stained with the Ziehl-Neelsen method, which showed short, pale AFB. A crude boil DNA preparation was made from the positive culture, and an in-house multiplex PCR to identify Mycobacterium spp. was performed (2). No PCR products were detected, and the Mycobacterium genus-specific band was absent. Similarly, no Mycobacterium genus band was detected by using a PCR-hybridization method (Common Mycobacteria line probe assay, Hain Lifesciences GmbH, Nehren, Germany) (3). DNA sequencing was performed on the Segniliparus rugosus strain NQ1 (GenBank accession no. {type:entrez-nucleotide,attrs:{text:FJ593188,term_id:221554550,term_text:FJ593188}}FJ593188), and a 1,250-bp fragment of the ribosomal 16S loci was obtained. A BLAST search (GenBank) was then performed on the sequence information obtained. The DNA sequence gave a 100% match to that of Segniliparus rugosus (GenBank accession no. {type:entrez-nucleotide,attrs:{text:AY608920,term_id:50660935,term_text:AY608920}}AY608920) (4). Drug susceptibility testing (DST) was attempted by using disk diffusion with Mueller-Hinton plates but was unsuccessful because of insufficient growth and indistinct margins. A commercially available microbroth dilution assay was used to determine the MICs for 12 antimicrobial drugs. The Sensititre Broth MIC Method for Rapidly Growing Mycobacteria, Nocardia, and Other Aerobic Actinomycetes (Trek Diagnostic Systems, Cleveland, OH, USA) was used according to manufacturer’s instructions (5). However, problems still occurred because of inadequate growth of the organism using the testing media approved for mycobacteria (6,7). Superior results were obtained when the cation-adjusted Mueller-Hinton broth with TES buffer (Trek Diagnostic Systems), which is used routinely in this assay, was substituted with an internally prepared Middlebrook 7H9 broth (Becton Dickinson) (1). DST results are similar to those previously reported for other strains of S. rugosus (Table) (1). The strain had rough, wrinkled colonial morphology on both blood agar and 7H11 plates. Growth was optimal at 35°C on 7H11 media. Arylsulfatase activity was weakly positive at 3 days and positive at 14 days. Growth on Lowenstein-Jensen (LJ) medium and on LJ with 5% sodium chloride medium occurred at 6–7 days. The strain was negative for both nitrate reductase and tween hydrolysis. Mycolic acid high-pressure liquid chromotography was performed (8), and the pattern obtained matched that of type strain CDC 945 ({type:entrez-nucleotide,attrs:{text:AY608920,term_id:50660935,term_text:AY608920}}AY608920) previously reported (4). The pattern had a double cluster of adjoining eluting peaks with the last peak co-eluting with the internal high standard. Only 3 other cases of Segniliparus spp. infection (none from Australia) have been reported. More remains to be learned about the effects of lung infections with Segniliparus spp. in cystic fibrosis patients. Although this patient improved clinically after treatment with antimicrobial drugs, she is still infected and will likely remain chronically infected. Because this genus is acid fast by the Ziehl-Neelsen method, laboratory workers and clinicians must be aware that AFB seen in pulmonary specimens from cystic fibrosis patients are not necessarily from the genus Mycobacterium and may be from the genus Segniliparus. Table Antimicrobial susceptibility patterns for Segniliparus rugosus strain in a cystic fibrosis patient, Australia

Antimicrobial Drug Use and Antibiotic-Resistant Bacteria

We appreciate the comments by Dr. Bellissimo-Rodrigues regarding our article analyzing risk factors for surveillance-culture positivity with extended-spectrum β-lactamase (ESBL)–producing bacteria (1). We agree with the author that patient-to-patient transmission is a potentially important causal factor in the emergence of resistance for ESBL-producing bacteria as well as for other antimicrobial drug–resistant bacteria, such as vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, and drug-resistant Pseudomonas and Acinetobacter spp. For each of these resistant organisms, a complicated interplay likely exists between the causal importance of antibiotic selective pressure and patient-to-patient transmission by healthcare workers (2–4). The relative importance of these 2 causal mechanisms needs to be determined for each individual antimicrobial-resistant bacterium. The relative causal importance may be different for different outcomes: colonization on admission, colonization acquisition, and progression from colonization to infection. Understanding the relative importance for each of these outcomes is needed before determining whether infection control interventions or antimicrobial drug stewardship policies will be effective. For example, we have published work that demonstrates that patient-to-patient transmission is important for colonization acquisition of ESBL-producing Klebsiella spp. and Escherichia coli (5). We believe that a couple of points require clarification. In our article, we looked at risk factors for colonization with ESBL-producing bacteria on admission to an intensive care unit. We did not examine risk factors for selecting ESBL-producing bacteria as the letter implies. For the antimicrobial drugs identified as potential risk factors, we clearly stated in the discussion that the risk factors identified may be causally related to the outcome of ESBL-colonization or may only be statistically associated. We argue that even risk factors identified are not causal; they may be important because they can help determine which patients may need empiric antimicrobial drug therapy targeted to the ESBL-producing bacteria. Future research work is still needed to assess the relative importance of patient-to-patient transmission versus antimicrobial selective pressure.

Breast Abscess Bacteriologic Features in the Era of Community-Acquired Methicillin-Resistant Staphylococcus aureus Epidemics

Increasing rates of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections have also affected the microbial profile of breast abscesses. To update the decade-old bacteriologic description of breast abscesses to improve the choice of initial antibacterial drug therapy. Retrospective case series. County hospital emergency department. Forty-four women (mean age, 41 years; age range, 20-63 years) with breast abscesses. All cultures from the breast abscesses of patients were reviewed. The microbiologic features and sensitivities of breast abscesses. Of 46 specimens only 28 showed bacterial yield (61%). Of these, 11 (39%) were polymicrobial, for an average of 1.4 isolates per specimen. The most common organism was S aureus, present in 12 of 37 aerobic cultures (32%), with MRSA in 7 (58%). The remaining organisms included coagulase-negative Staphylococcus (16%), diphtheroids (16%), Pseudomonas aeruginosa (8%), Proteus mirabilis (5%), and other isolates (22%). All MRSA was sensitive to clindamycin, trimethoprim-sulfamethoxazole, and linezolid. Only 2 patients (29%) were sensitive to levofloxacin. Two anaerobic cultures were positive for Propionibacterium acnes and Peptostreptococcus anaerobius. Staphylococcus aureus is the most common pathogenic organism in modern breast abscesses. Many breast abscesses have community-acquired MRSA, with more than 50% of all S aureus and 19% of all cultures being MRSA. This finding parallels the local and national increases in MRSA reported in other soft-tissue infections. With increasing bacterial resistance and more minimally invasive management of breast abscesses, understanding the current bacteriologic profile of these abscesses is essential to determining the correct empirical antibiotic drug therapy.

Initial Treatment With Lansoprazole in Young Dyspeptic Patients With Negative Urea Breath Test Result: A Randomized Controlled Trial With 12-Month Follow-Up

Although empirical antisecretory drug therapy is recommended to young dyspeptic patients without alarming features, the effectiveness of this approach remains undetermined. We evaluated the long-term effects of an initial 12-wk course of lansoprazole in young dyspeptic patients without Helicobacter pylori (H. pylori) infection. Patients who were less than 45 yr and presented with at least 3 months of dyspepsia in the absence of alarming features were eligible. They were offered (13)C-urea breath test (UBT) to determine H. pylori status and all symptomatic patients with negative UBT were randomized to receive lansoprazole 30 mg daily or placebo for 12 wk. Those who had previous endoscopy or positive UBT were excluded. Primary end point was the proportion of patients with treatment failure, defined as worsening of global dyspeptic symptom, while on study medication. Patients were followed up for 26 wk for global dyspeptic symptom as determined by 7-point Likert scale. Quality-of-life assessment (SF-36), need of endoscopy, and utilization of other health-care services were monitored for 52 wk. A total of 157 dyspeptic patients were randomized. At the end of 12-wk treatment, the proportion of patients with treatment failure was similar in the lansoprazole (33.3%) and placebo (30.3%) groups (P= 0.74). Patients' global assessment of their dyspeptic symptom was comparable at all time points measured. There was also no significant difference in the SF-36 mental and physical summary scales. At the end of 52 wk, there was no difference in the proportion of patients who underwent endoscopy, had additional medical consultations, or used other nonstudy medications between the two groups. Lansoprazole is not effective in the initial management of young dyspeptic patients without H. pylori infection.

"Mycobacterium tilburgii" Infections

"<i>Mycobacterium tilburgii</i>" Infections