Acute otitis media and otitis media with effusion are common childhood disorders, a source of significant morbidity, and a leading cause of antibiotic prescription in primary health care. Although effective treatments are available, some shortcomings remain, and thus better treatments would be welcome. Recent discoveries within the field of otitis media research relating to its etiology and pathogenesis have led to further investigation aimed at developing novel treatments. This article provides a review of the latest evidence relating to the understanding of acute otitis media and otitis media with effusion, current treatment strategies, their limitations, new areas of research, and novel strategies for treatment.
otitis media; ear; hearing; infection; biofilm; antibiotics
Nosocomial or more exactly, hospital-acquired (HAP) and ventilator-associated pneumonia (VAP) are frequent conditions when treating intensive care unit (ICU) patients that are only exceeded by central line-associated bloodstream infections. In Germany, approximately 18,900 patients per year suffer from a VAP and another 4,200 from HAP. We therefore reviewed the current guidelines about HAP and VAP, from different sources, regarding the strategies to address individual patient risks and medication strategies for initial intravenous antibiotic treatment (IIAT).
Material and methods
We conducted an analysis of the recent guidelines for the treatment of HAP. The current guidelines of the American Thoracic Society, the treatment recommendations of the Paul-Ehrlich-Gesellschaft (PEG), the guidelines from the British Society for Antimicrobial Chemotherapy, the VAP guideline of the Canadian Critical Care trials group, as well as the new German S3-guideline for HAP were examined.
All guidelines are based on grading systems that assess the evidence underlying the recommendations. However, each guideline uses different grading systems. One common aspect of these guidelines is the risk assessment of the patients for decision making regarding IIAT. Most guidelines have different recommendations depending on the risk of the presence of multidrug resistant (MDR) bacteria. In guidelines using risk assessment, for low-risk patients (early onset, no MDR risk) aminopenicillins with beta-lactamase inhibitors (BLI), second or third generation cephalosporins, quinolones, or ertapenem are recommended. For patients with higher risk, imipenem, meropenem, fourth generation cephalosporins, ceftazidime or piperacillin/tazobactam are recommended. The PEG recommendations include a combination therapy in cases of very high risk (late onset, MDR risk, ICU, and organ failure) of either piperacillin/tazobactam, dori-, imi- or meropenem or cefepime or ceftazidime with ciprofloxacin, levofloxacin, fosfomycin or an aminoglycoside. For the treatment of HAP caused by methicillin-resistant Staphylococcus aureus (MRSA), either linezolid or vancomycin is recommended. With regard to the ZEPHyR-trial, linezolid has shown higher cure rates but, no difference in overall survival. Economic analyses show the relevance of guideline-adherent IIAT (GA-IIAT). Besides significantly better clinical outcomes, patients with GA-IIAT cause significantly lower costs (€28,033 versus (vs) €36,139) (P=0.006) and have a shorter length of stay in hospital (23.9 vs 28.3 days) (P=0.022).
We conclude that most current treatment guidelines take into account the individual patient risk and that the correct choice of IIAT affects clinical as well as economical outcomes.
nosocomial pneumonia; ventilator; assoc. pneumonia; antibiotics; guidelines; review
Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to almost all antimicrobial agents, is associated with substantial morbidity and mortality, and poses a serious threat to public health. The ongoing worldwide spread of this pathogen emphasizes the need for immediate intervention. This article reviews the global spread and risk factors for CRKP colonization/infection, and provides an overview of the strategy to combat CRKP dissemination.
carbapenem-resistant Klebsiella pneumoniae; infection control; cohort; active surveillance; rectal cultures
Induction of ampC β-lactamase expression can often compromise antibiotic treatment and is triggered by several β-lactams (such as cefoxitin and imipenem) and by the β-lactamase inhibitor clavulanic acid. The novel β-lactamase inhibitor avibactam (NXL104) is a potent inhibitor of both class A and class C enzymes. The potential of avibactam for induction of ampC expression in Enterobacter cloacae was investigated by ampC messenger ribonucleic acid quantitation. Cefoxitin and clavulanic acid were confirmed as ampC inducers, whereas avibactam was found to exert no effect on ampC expression. Thus, avibactam is unlikely to diminish the activity of any partner β-lactam antibiotic against AmpC-producing organisms.
β-lactamase; ampC; induction; NXL104; avibactam
Urinary tract infection (UTI) is a common bacterial infection during pregnancy and a significant cause of perinatal and maternal morbidity and mortality. The causative bacteria have remained virtually the same although with variations in individual prevalence. There has been an increasing resistance by these bacteria to the commonly available antibiotics.
To determine the prevalence of UTI, the common causative bacteria, and their antibiotic sensitivity pattern among pregnant women with UTI.
This is a descriptive study that was carried out at the Obstetrics Department of two tertiary institutions in Abakaliki, Ebonyi State, Nigeria (Federal Medical Center and Ebonyi State University Teaching Hospital) over a period of 12 months. Midstream urine specimens from selected pregnant women with clinical features of UTI were collected for microscopy, culture, and sensitivity. The results were analyzed with the 2008 Epi Info™ software.
A total of 542 pregnant women presented with symptoms of UTI and were recruited for the study over the study period. Of the 542 pregnant women, 252 (46.5%) had significant bacteriuria with positive urine culture and varying antibiotic sensitivity pattern. The prevalence of symptomatic UTI was 3%. Escherichia coli was the most common bacteria isolated with a percentage of 50.8%. Other isolated micro organisms included Stapylococcus aereus (52 cultures, 20.6%), Proteus mirabilis (24 cultures, 9.5%), S. saprophyticus (18 cultures, 7.1%), Streptococcus spp. (14 cultures, 5.6%), Citrobacter spp. (5 cultures, 2.0%), Klebsiella spp. (4 cultures, 1.6%), Enterobacter spp. (4 cultures, 1.6%), and Pseudomonas spp. (3 cultures, 1.2%). Levofloxacin had the highest overall antibiotic sensitivity of 92.5%. Others with overall antibiotic sensitivity pattern greater than 50% included cefpodoxime (87.3%), ofloxacin (77.4%), ciprofloxacin (66.7%), ceftriaxone (66.7%), and gentamicin (50.8%).
E. coli was the most common etiological agent of UTI in pregnancy with Enterococcus (Staphylococcus) gaining prominence. Cephalosporin and quinolones were shown to be very effective against the organisms causing UTI in these pregnant women.
antibiotic sensitivity pattern; pregnancy; urinary tract infection; uropathogens
The management of infections caused by multidrug-resistant Gram-negative bacteria, particularly Pseudomonas aeruginosa, continues to be a significant challenge to clinicians. Ceftolozane/tazobactam is a novel antibacterial and β-lactamase-inhibitor combination that has shown appreciable activity against wild-type Enterobacteriaceae and potent activity against P. aeruginosa. Moreover, ceftolozane/tazobactam has not demonstrated cross-resistance to other antimicrobial classes, particularly those affected by extended-spectrum β-lactamases, AmpC β-lactamase, a loss in porin channels, or the overexpression of efflux pumps in P. aeruginosa. Ceftolozane/tazobactam has completed two Phase II clinical trials in complicated intra-abdominal and complicated urinary tract infections. A Phase III, multicenter, prospective, randomized, open-label study has been initiated to evaluate the safety and efficacy of ceftolozane/tazobactam versus piperacillin/tazobactam for the treatment of ventilator-associated pneumonia. A Medline search of articles from inception to May 2013 and references for selected citations was conducted. Data from abstracts presented at conferences were also appraised. This article reviews the antimicrobial, pharmacokinetic, and pharmacodynamic profile of ceftolozane/tazobactam, and discusses its potential role in therapy.
CXA-201; CXA-101; FR264205; Pseudomonas aeruginosa
Tuberculosis (TB) is a major public health problem with high mortality and morbidity rates, especially in low-income countries. Disturbingly, the emergence of multidrug resistant (MDR) and extensively drug resistant (XDR) TB cases has worsened the situation, raising concerns of a future epidemic of virtually untreatable TB. Indeed, the rapid diagnosis of MDR TB is a critical issue for TB management. This study is an attempt to establish a rapid diagnosis of MDR TB by sequencing the target fragments of the rpoB gene which linked to resistance against rifampicin and the katG gene and inhA promoter region, which are associated with resistance to isoniazid.
For this purpose, 133 sputum samples of TB patients from Morocco were enrolled in this study. One hundred samples were collected from new cases, and the remaining 33 were from previously treated patients (drug relapse or failure, chronic cases) and did not respond to anti-TB drugs after a sufficient duration of treatment. All samples were subjected to rpoB, katG and pinhA mutation analysis by polymerase chain reaction and DNA sequencing.
Molecular analysis showed that seven strains were isoniazid-monoresistant and 17 were rifampicin-monoresistant. MDR TB strains were identified in nine cases (6.8%). Among them, eight were traditionally diagnosed as critical cases, comprising four chronic and four drug-relapse cases. The last strain was isolated from a new case. The most recorded mutation in the rpoB gene was the substitution TCG > TTG at codon 531 (Ser531 Leu), accounting for 46.15%. Significantly, the only mutation found in the katG gene was at codon 315 (AGC to ACC) with a Ser315Thr amino acid change. Only one sample harbored mutation in the inhA promoter region and was a point mutation at the −15p position (C > T).
The polymerase chain reaction sequencing approach is an accurate and rapid method for detection of drug-resistant TB in clinical specimens, and could be of great interest in the management of TB in critical cases to adjust the treatment regimen and limit the emergence of MDR and XDR strains.
Morocco; Mycobacterium tuberculosis; multidrug resistance; rpoB; katG; inhA promoter
Nontyphoidal Salmonella (NTS) species are important food-borne pathogens that cause gastroenteritis and bacteremia, and are responsible for a huge global burden of morbidity and mortality. The aim of this study was to investigate the prevalent serogroups and antibiotic resistance of NTS in our region.
We reviewed the serogroup distribution and antimicrobial susceptibility patterns of NTS strains obtained from 158 stool specimens of patients with acute diarrheal infection attending the outpatient and inpatient department at a university hospital in the Eastern Province of Saudi Arabia in the period from September, 2008 to April, 2011. A retrospective analysis of the 158 patients with NTS infection was conducted to determine the most prevalent NTS serogroups causing acute gastroenteritis and their antimicrobial susceptibility patterns.
At this teaching hospital, a total of 17,436 fecal samples were analyzed during the 2008–2011 study period. Of these specimens, 158 tested positive for NTS, giving an overall prevalence of 9.06 per 1,000. Of 158 NTS cases, serogroup D1 (25.3%) was the most prevalent, followed by serogroup B (19.6%), and serogroup C1 (18.9). One third of all NTS serogroup strains tested were resistant to tetracycline. The NTS strains showed resistance to ampicillin (31.3%), amoxicillin/clavulanic acid (29.9%), trimethoprim/sulfamethoxazole (20.9%), and cefotaxime (14.93%).
The findings of this study support the concern that use of antibiotics in animal feeds may contribute to acquisition of resistance in food-borne bacteria, such as Salmonella. Our study also concludes that the prevalence of NTS in the Eastern Province of Saudi Arabia is very low compared with other studies worldwide.
nontyphoidal Salmonella; serogroups; prevalence; antimicrobial resistance; Saudi Arabia
Influenza virus is a pathogen that causes morbidity and mortality worldwide. Whereas vaccination is important for prevention of disease, given its limitations, antiviral therapy is at the forefront of treatment and also plays a role in prevention. Currently, two classes of antiviral medications, the adamantanes and the neuraminidase inhibitors, are approved for treatment. Given the resistance patterns of circulating influenza, adamantanes are not recommended. Within the US, two neuraminidase inhibitors are currently approved for both treatment and prevention, while worldwide there are four available. In this review, we will briefly discuss the epidemiology and pathology of influenza and then discuss neuraminidase inhibitors: their mechanism of action, resistance, development, and future applications.
influenza; antiviral; neuraminidase; resistance
Staphyloxanthin is a virulence factor which protects Staphylococcus aureus in stress conditions. We isolated two pigment variants of S. aureus and one strain of Pseudomonas aeruginosa from a single wound infection. S. aureus variants displayed white and yellow colony phenotypes. The sequence of the operons for staphyloxanthin synthesis indicated that coding and promoter regions were identical between the two pigment variants. Quorum sensing controls pigment synthesis in some bacteria. It is also shown that P. aeruginosa quorum-sensing molecules affect S. aureus transcription. We explored whether the co-infecting P. aeruginosa can affect pigment production in the white S. aureus variant. In co-culture experiments between the white variants and a selected number of Gram-positive and Gram-negative bacteria, only P. aeruginosa induced pigment production in the white variant. Gene expression analysis of the white variant did not indicate upregulation of the crtM and other genes known to be involved in pigment production (sigB, sarA, farnesyl pyrophosphate synthase gene [FPP-synthase], hfq). In contrast, transcription of the catalase gene was significantly upregulated after co-culture. P. aeruginosa-induced pigment synthesis and catalase upregulation correlated with increased resistance to polymyxin B, hydrogen peroxide, and the intracellular environment of macrophages. Our data indicate the presence of silent but functional staphyloxanthin synthesis machinery in a white phenotypic variant of S. aureus which is activated by a co-infecting P. aeruginosa via inter-species communication. Another S. aureus virulence factor, catalase is also induced by this co-infecting bacterium. The resulting phenotypic changes are directly correlated with resistance of the white variant to stressful conditions.
Staphylococcus aureus; Pseudomonas aeruginosa; staphyloxanthin; catalase; interspecies interaction
Acute gastroenteritis, characterized by the onset of diarrhea with or without vomiting, continues to be a major cause of morbidity and mortality in children in mostly resource-constrained nations. Although generally a mild and self-limiting disease, gastroenteritis is one of the most common causes of hospitalization and is associated with a substantial disease burden. Worldwide, up to 40% of children aged less than 5 years with diarrhea are hospitalized with rotavirus. Also, some microorganisms have been found predominantly in resource-constrained nations, including Shigella spp, Vibrio cholerae, and the protozoan infections. Prevention remains essential, and the rotavirus vaccines have demonstrated good safety and efficacy profiles in large clinical trials. Because dehydration is the major complication associated with gastroenteritis, appropriate fluid management (oral or intravenous) is an effective and safe strategy for rehydration. Continuation of breastfeeding is strongly recommended. New treatments such as antiemetics (ondansetron), some antidiarrheal agents (racecadotril), and chemotherapeutic agents are often proposed, but not yet universally recommended. Probiotics, also known as “food supplement,” seem to improve intestinal microbial balance, reducing the duration and the severity of acute infectious diarrhea. The European Society for Paediatric Gastroenterology, Hepatology and Nutrition and the European Society of Paediatric Infectious Diseases guidelines make a stronger recommendation for the use of probiotics for the management of acute gastroenteritis, particularly those with documented efficacy such as Lactobacillus rhamnosus GG, Lactobacillus reuteri, and Saccharomyces boulardii. To date, the management of acute gastroenteritis has been based on the option of “doing the least”: oral rehydration-solution administration, early refeeding, no testing, no unnecessary drugs.
acute infective gastroenteritis; diarrhea; oral rehydration solution; children; vomiting; probiotics
The triazole class of antifungal drugs comprises first-line agents for the treatment of several invasive fungal diseases. Isavuconazole is a novel broad-spectrum triazole agent. Here we summarize its characteristics and compare it with the currently available antifungal agents. Isavuconazole is administered as a prodrug, and it is water soluble. Oral and intravenous formulations are available. Its intravenous formulation does not contain cyclodextrin, which is an advantage over voriconazole, considering the potential for nephrotoxicity of cyclodextrin. As with other azoles, isavuconazole requires a loading dose. Due to its prolonged half-life, a once-a-day regimen is possible. Considering that isavuconazole shares the same mechanism of action with the other triazoles, cross-resistance is an important concern in the class. Tolerability and safety profiles are favorable, and no serious adverse events have been consistently reported. Significant interactions with drugs metabolized by cytochrome P450 are expected to occur, especially with substrates and inducers of the CYP3A4 enzyme. Isavuconazole has in vitro activity against most medically important fungi, including species of Candida, Aspergillus, and Cryptococcus. It has some activity against the agents of mucormycosis. Clinical data regarding isavuconazole remain limited because ongoing trials have not yet been completed or published. Isavuconazole has the potential to become first-line therapy for invasive aspergillosis. It also has the potential for use in the context of antifungal prophylaxis, salvage therapy, or in combination regimens. Results of clinical trials are ultimately expected in order to adequately position isavuconazole in the current antifungal armamentarium.
isavuconazole; invasive fungal infections; antifungals; triazoles; Aspergillus
Over the last ten years, genome sequencing capabilities have expanded exponentially. There have been tremendous advances in sequencing technology, DNA sample preparation, genome assembly, and data analysis. This has led to advances in a number of facets of bacterial genomics, including metagenomics, clinical medicine, bacterial archaeology, and bacterial evolution. This review examines the strengths and weaknesses of techniques in bacterial genome sequencing, upcoming technologies, and assembly techniques, as well as highlighting recent studies that highlight new applications for bacterial genomics.
bacterial genome sequencing assembly review
Some cases of sudden death (SD) have been attributed to communicable diseases (CD) in middle- and low-income countries of the world even in this 21st century. CDs produce clinical symptoms and signs over several days before culminating in death. They are also amenable to treatment with antimicrobials if affected persons present early. We sought to find out the incidence of CD-related SD at the Ladoke Akintola University of Technology Teaching Hospital (Osogbo, Osun State, Nigeria) – a tertiary health facility in southwest Nigeria – and the prevailing associated factors.
We conducted a retrospective study of CD-related SD in adult patients aged 18 years and older that occurred from January 2003 to December 2011. The Statistical Package for the Social Sciences version 16 was used for analysis of the generated data. Percentages and frequencies were calculated.
There were 17 (39.6%) CD-related SDs out of the 48 cases of SD studied. CD-related SD also accounted for 2.4% of all adult medical admissions. The mean age of the patients was 37.6 ± 11.6 years, age range of 25–62 years, mode of 25 years, and median 34 years. The male-to-female ratio was 1.8:1. Typhoid sepsis was responsible for SD in 47.1% of patients, pulmonary tuberculosis in 17.7% of patients, and lobar pneumonia in 17.7% of patients. The most affected age group was the 20–29-year-old group (41.2%), while the unskilled occupational group was the most affected occupational group with 35.3% of them having SD. Most of the patients with acute bacterial infection died of multiple organ failure.
There is an urgent need to step up public health strategies to curtail infections in this environment, encourage better use of the existing health facilities by the people, and the government should strive hard to make health a top priority.
infections; septic shock; typhoid sepsis; pulmonary tuberculosis; HIV/AIDS; public health
It is important to identify patients who are at risk for infections with extended-spectrum β-lactamase (ESBL)-producing bacteria in order to reduce mortality, to avoid spread of resistant bacteria in hospitals, and to minimize the number of patients receiving unnecessary treatment with broad-spectrum antibiotics. A case-control survey among Swedish patients was performed at Skåne University Hospital to identify risk factors for developing an infection with ESBL-producing Escherichia coli in a low endemic country.
We used a computerized database to identify patients with growth of ESBL-producing E. coli (n = 109) in urine or blood cultures and an equal number of controls matched for age and gender with non ESBL-producing E. coli in urine and blood diagnosed between January and October 2008. We used unadjusted P-values.
Patients with ESBL-producing E. coli had a significantly (P < 0.05) higher likelihood of having traveled to Asia including Turkey and the Middle East including Egypt (14/58) than the non-ESBL-positive group (4/53). Hospital stay during the previous year (P < 0.04), especially for more than one month, was another significant (P = 0.01) risk factor for infection with ESBL-producing E. coli (8/58). A stay in the surgical department was a further risk factor (P < 0.01).
In this study, we identified 22 of 58 (38%) patients with ESBL-producing E. coli by considered significant risk factors before starting antibiotics.
extended-spectrum β-lactamase; Enterobacteriaceae; resistant bacteria; risk factors; Escherichia coli
Infectious diseases are known as one of the most life-threatening disabilities worldwide. Approximately 13 million deaths related to infectious diseases are reported each year. The only way to combat infectious diseases is by chemotherapy using antimicrobial agents and antibiotics. However, due to uncontrolled and unnecessary use of antibiotics in particular, surviving bacteria have evolved resistance against several antibiotics. Emergence of multidrug resistance in bacteria over the past several decades has resulted in one of the most important clinical health problems in modern medicine. For instance, approximately 440,000 new cases of multidrug-resistant tuberculosis are reported every year leading to the deaths of 150,000 people worldwide. Management of multidrug resistance requires understanding its molecular basis and the evolution and dissemination of resistance; development of new antibiotic compounds in place of traditional antibiotics; and innovative strategies for extending the life of antibiotic molecules. Researchers have begun to develop new antimicrobials for overcoming this important problem. Recently, platensimycin – isolated from extracts of Streptomyces platensis – and its analog platencin have been defined as promising agents for fighting multidrug resistance. In vitro and in vivo studies have shown that these new antimicrobials have great potential to inhibit methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and penicillin-resistant Streptococcus pneumoniae by targeting type II fatty acid synthesis in bacteria. Showing strong efficacy without any observed in vivo toxicity increases the significance of these antimicrobial agents for their use in humans. However, at the present time, clinical trials are insufficient and require more research. The strong antibacterial efficacies of platensimycin and platencin may be established in clinical trials and their use in humans for coping with multidrug resistance may be allowed in the foreseeable future.
drug resistance; antibiotics; bacterial infections; platensimycin; platencin
The characteristics and antimicrobial resistance profiles of Staphylococcus aureus differs according to geographical regions and in relation to antibiotic usage. The aim of this study was to determine the biochemical characteristics of the prevalent S. aureus from Ekiti State, Nigeria, and to evaluate three commonly used disk diffusion methods (cefoxitin, oxacillin, and methicillin) for the detection of methicillin resistance in comparison with mecA gene detection by polymerase chain reaction.
Materials and methods
A total of 208 isolates of S. aureus recovered from clinical specimens were included in this study. Standard microbiological procedures were employed in isolating the strains. Susceptibility of each isolate to methicillin (5 μg), oxacillin (1 μg), and cefoxitin (30 μg) was carried out using the modified Kirby–Bauer/Clinical and Laboratory Standard Institute disk diffusion technique. They were also tested against panels of antibiotics including vancomycin. The conventional polymerase chain reaction method was used to detect the presence of the mecA gene.
Phenotypic resistance to methicillin, oxacillin, and cefoxitin were 32.7%, 40.3%, and 46.5%, respectively. The mecA gene was detected in 40 isolates, giving a methicillin-resistant S. aureus (MRSA) prevalence of 19.2%. The S. aureus isolates were resistant to penicillin (82.7%) and tetracycline (65.4%), but largely susceptible to erythromycin (78.8% sensitive), pefloxacin (82.7%), and gentamicin (88.5%). When compared to the mecA gene as the gold standard for MRSA detection, methicillin, oxacillin, and cefoxitin gave sensitivity rates of 70%, 80%, and 100%, and specificity rates of 76.2%, 69.1%, and 78.5% respectively.
When compared with previous studies employing mecA polymerase chain reaction for MRSA detection, the prevalence of 19.2% reported in Ekiti State, Nigeria in this study is an indication of gradual rise in the prevalence of MRSA in Nigeria. A cefoxitin (30 μg) disk diffusion test is recommended above methicillin and oxacillin for the phenotypic detection of MRSA in clinical laboratories.
evaluation; disk diffusion; mecA gene; MRSA; Nigeria
Because the use of procalcitonin has been advocated as a marker of bacterial infection, this study was carried out to determine the usefulness of serum PCT as an early marker to decide upon intervention for urinary tract infection.
The subjects were 68 patients with urinary tract infection (UTI) in whom we measured serum procalcitonin concentration at the start of treatment.
There were 47 patients with nonobstructed UTI and 21 with obstructed UTI. All patients with obstructed UTI were subjected to intervention. There were significant differences in procalcitonin, white blood cells, and creatinine levels between patients with nonobstructed and obstructed UTI (P < 0.05).
Although this retrospective study comprised a small number of patients, we found that procalcitonin was a useful marker to decide upon urinary intervention.
procalcitonin; intervention; urinary tract infection; urology
Group C Streptococcus (GCS) is a rare cause of bacteremia in humans. It is mostly associated with zoonological infections. Although GCS can be part of the normal oral, skin, and genitourinary fora, an infection with this pathogen can be highly virulent, causing rapid, disseminating disease. With a mortality of about 25%, the poor prognosis is linked to the severity of illness and the high level of virulence of the organism. Only a few cases of GCS meningitis have been reported. We present the first case of GCS meningitis with cavernous sinus thrombosis.
streptococcus group C; cavernous sinus thrombosis; meningitis
Antibiotics are frequently used among people with sickle cell anemia (homozygous SS or HbSS disease), especially for prophylaxis. However, the relationship between antibiotic resistance and people with HbSS disease has not been adequately studied, especially in the developing world. The objectives of the study were (1) to compare antibiotic resistance patterns of nasal Staphylococcus aureus between children with HbSS disease and children without HbSS disease (healthy children) and (2) to evaluate nasopharyngeal carriage of antibiotic-resistant Streptococcus pneumoniae among children with HbSS disease.
This was a prospective cross-sectional study, and the subjects were children under 12 years old. Nasal swabs were collected from 50 children with HbSS disease and 50 children without HbSS disease. Nasopharyngeal swabs were collected from another group of 92 children with HbSS disease. The nasal and nasopharyngeal swabs were cultured for S. aureus and S. pneumoniae, respectively. Susceptibility testing was carried out on the S. aureus and S. pneumoniae isolates for various antibiotics, including penicillin, ampicillin, cefuroxime, erythromycin, cloxacillin, and cotrimoxazole.
The carriage rates of S. aureus among pediatric subjects with HbSS disease and those without HbSS disease were 48% and 50%, respectively (P > 0.05). S. pneumoniae carriage among the pediatric subjects with HbSS disease was 10%. Antibiotic resistance patterns of S. aureus carried by children with HbSS disease and children without HbSS disease were similar, and the S. aureus resistance rates were >40% for the various antibiotics, with the exception of erythromycin and cloxacillin. Low levels of S. pneumoniae resistance (0%–11%) were observed for the various antibiotics tested except cotrimoxazole, which showed an extremely high-percentage resistance (100%).
Sickling status is not a risk factor for carriage of S. aureus. In this cohort of Ghanaian children with HbSS disease, S. aureus is higher in carriage and more antibiotic-resistant, compared to S. pneumoniae.
Paediatric; sickle cell anaemia; antibiotic resistance; Ghana
It is not known whether or not ward-specific antimicrobial use density (AUD) affects the ratio of methicillin-resistant Staphylococcus aureus (MRSA) in culture-positive S. aureus. A 60-month study was attempted to ascertain the association between inpatient MRSA ratio and ward-specific AUDs as well as the former and latter study intervals, specimen types, and ward specialty. During the study, the professionals in infection control regulated the use of broad-spectrum antimicrobials and those for MRSA. By both month and ward, the ratio of inpatients positive for MRSA to those positive for S. aureus was calculated. Factors associated with MRSA ratio included AUDs averaged for the sampling month and its previous month, outpatient MRSA ratio by age, ward specialty, specimen type, and half intervals to represent historical changes. Of a total of 4,245 strains of S. aureus isolated during the 5-year study, 2,232 strains (52.6%) were MRSA. By year, outpatient MRSA ratio at age ≥15 decreased in later years, as did inpatient MRSA ratio. Multivariate analysis for inpatient MRSA ratio revealed a positive risk in AUDs for meropenem (odds ratio [OR] 1.761; 95% confidence interval [CI] 1.761–2.637, P = 0.01), imipenem-cilastatin (OR 1.583; 95% CI 1.087–2.306, P = 0.02), ampicillin-sulbactam (OR 1.623; 95% CI 1.114–2.365, P = 0.01), and minocycline (OR 1.680; CI 1.135–2.487, P = 0.01), respiratory care ward (OR 2.292; 95% CI 1.085–4.841, P = 0.03), and outpatient MRSA ratio (OR 1.536; 95% CI 1.070–2.206, P = 0.02). Use of broad-spectrum antimicrobials, such as meropenem, imipenem-cilastatin, and ampicillin-sulbactam may increase inpatient MRSA ratio. Ward factor should be included in MRSA surveillance because of the possible effect on AUD and considering patients’ backgrounds.
surveillance; respiratory tract; methicillin-resistant Staphylococcus aureus
The detection rate of CTX-M-type β-lactamase-producing Enterobacteriaceae in Japan has significantly increased. Nursing homes may be a reservoir of antibiotic-resistant bacteria. Therefore, we determined the prevalence of, and risk factors associated with, fecal carriage of CTX-M-type β-lactamase-producing Enterobacteriaceae among nursing home residents. A total of 225 stool samples were collected for phenotypic and genotypic identification of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Multivariate analysis was performed to identify the risk factors associated with fecal carriage of CTX-M producers. The prevalence of CTX-M-type ESBL-producing Enterobacteriaceae, as confirmed by phenotypic and genotypic methods, was 19.6% (44 of 225 samples). Escherichia coli was the predominant CTX-M-type ESBL-producing bacterium among these isolates (41 of 44 isolates). Genotyping of blaCTX-M gene-positive isolates showed that 30 (68.2%), 13 (29.5%), and 1 (2.3%) of 44 samples belonged to groups CTX-M-9, CTX-M-1 and CTX-M-2, respectively. Among the CTX-M-type ESBL-producing Enterobacteriaceae found in nursing homes, 95.5% (42 of 44 isolates) were co-resistant to quinolone antibiotics. In multivariate logistic regression analysis, inability to turn over in bed, diabetes, and invasive procedures within the last 2 years were the only variables independently associated with fecal carriage of CTX-M-type ESBL producers. Nursing home residents in Japan exhibit a high prevalence of CTX-M-type ESBL-producing Enterobacteriaceae carriage, with a high level of co-resistance to quinolones.
Enterobacteriaceae; extended-spectrum beta-lactamase (ESBL); risk factors; fecal carriage; nursing homes; Japan
Asymptomatic bacteriuria in elderly individuals has been well described in institutionalized settings, but to a lesser extent in the community. The purpose of this study was to determine the pathogens responsible for asymptomatic bacteriuria in elderly and middle-aged individuals in Alajue-Ede, South-Western Nigeria, and to identify any associated factors. Mid-stream urine samples were collected from apparently healthy elderly and middle-aged volunteers who were participating in community health screening. Samples were processed and bacterial isolates were identified following standard procedures. In total, 128 volunteers (48 men, 76 women) participated in the study. Twenty-eight (22.6%) urinary pathogens were isolated, comprising Klebsiella species in five (17.9%), Pseudomonas aeruginosa in one (3.6%), Escherichia coli in 19 (67.9%), and Proteus species in three (10.7%) cases. Women were identified as being at higher risk of asymptomatic bacteriuria, and the prevalence also increased with increasing age in men. The elderly in this community have a high prevalence of asymptomatic bacteriuria, and screening for comorbid medical conditions may be of benefit.
asymptomatic bacteriuria; urinary pathogens; elderly; urinary tract infection
The epidemiology of Clostridium difficile infections (CDI) has evolved during the last decades, with an increase in the reported incidence, severity of cases, and rate of mortality and relapses. These increases have primarily affected some special populations including the elderly, patients requiring concomitant antibiotic therapy, patients with renal failure, and patients with cancer. Until recently, the treatment of CDI was limited to either metronidazole or vancomycin. New therapeutic options have emerged to address the shortcomings of current antibiotic therapy. Fidaxomicin stands out as the first-in-class oral macrocyclic antibiotic with targeted activity against C. difficile and minimal collateral damage on the normal colonic flora. Fidaxomicin has demonstrated performance not inferior to what is considered the “gold standard” available therapy for CDI, vancomycin, in two separate Phase III clinical trials, but with significant advantages, including fewer recurrences and higher rates of sustained clinical cures. Fidaxomicin constitutes an important development in targeted antibiotic therapy for CDI and must be considered as a first-line agent for patients with risk factors known to portend relapse and severe infection.
fidaxomicin; Clostridium difficile-associated diarrhea; CDAD; Clostridium difficile infection (CDI); vancomycin; metronidazole
Although invasive pulmonary aspergillosis (IPA) is more prevalent in immunocompromised patients, critical care clinicians need to be aware of the occurrence of IPA in the nontraditional host, such as a patient with chronic lung disease. The purpose of this study was to describe the IPA patient with chronic lung disease and compare the data with that of immunocompromised patients.
The records of 351 patients with Aspergillus were evaluated in this single-center, retrospective study for evidence and outcomes of IPA. The outcomes of 57 patients with chronic lung disease and 56 immunocompromised patients were compared. Patients with chronic lung disease were defined by one of the following descriptive terms: emphysema, asthma, idiopathic lung disease, bronchitis, bronchiectasis, sarcoid, or pulmonary leukostasis.
Baseline demographics were similar between the two groups. Patients with chronic lung disease were primarily defined by emphysema (61%) and asthma (18%), and immunocompromised patients primarily had malignancies (27%) and bone marrow transplants (14%). A higher proportion of patients with chronic lung disease had a diagnosis of IPA by bronchoalveolar lavage versus the immunocompromised group (P < 0.03). The major risk factors for IPA were found to be steroid use in the chronic lung disease group and neutropenia and prior surgical procedures in the immunocompromised group. Overall, 53% and 69% of chronic lung disease and immunocompromised patients were cured (P = 0.14); 55% of chronic lung patients and 47% of immunocompromised patients survived one month (P = 0.75).
Nontraditional patients with IPA, such as those with chronic lung disease, have outcomes and mortality similar to that in the more traditional immunocompromised population.
Aspergillus; moulds; intensive care units; chronic lung disease; antifungals