Diagnosis and antibiotic treatment of group a streptococcal pharyngitis in children in a primary care setting: impact of point-of-care polymerase chain reaction

BACKGROUND

To compare the sensitivity and specificity of the recommended 2-step rapid antigen detection test (RADT) with confirmatory culture vs the point-of-care (POC) polymerase chain reaction (PCR) Roche cobas® Liat® Strep A test for detection of group A Streptococcus (GAS) in pediatric patients with pharyngitis, and to investigate the impact of these tests on antibiotic use in a large pediatric clinic.

METHODS

This prospective, open-label study was conducted at a single site during fall/winter 2016-2017. A total of 275 patients aged 3 to 18 years with symptoms of pharyngitis had a throat-swab specimen analyzed using RADT, POC PCR, and culture. The sensitivity, specificity, and percentage agreement (95% CI) between assays and a laboratory-based nucleic acid amplification test were calculated. DNA sequencing was used to adjudicate discrepancies. The RADT or POC PCR result was provided to clinicians on alternating weeks to compare the impact on antibiotic use.

RESULTS

A total of 255 samples were evaluated; 110 (43.1%) were GAS positive. Sensitivities (95% CI) for POC PCR, RADT, and culture were 95.5% (89.7-98.5%), 85.5% (77.5-1.5%), and 71.8% (62.4-80.0%), respectively. Specificities (95% CI) for POC PCR, RADT, and culture were 99.3% (96.2-99.98%), 93.7% (88.5-97.1%), and 100% (97.5-100%), respectively. Compared with RADT, POC PCR resulted in significantly greater appropriate antibiotic use (97.1% vs 87.5%; P = .0065).

CONCLUSION

Under real-world conditions, RADT results were less specific and culture results were less sensitive than found in established literature and led to increased rates of inappropriate antibiotic use. POC PCR had high sensitivity and specificity and rapid turnaround times, and led to more appropriate antibiotic use.

TRIAL REGISTRATION

ID number ISRCTN84562679 . Registered October 162,018, retrospectively registered.

A rationale for combination ampicillin and daptomycin in renal transplant patients with enterococcal infective endocarditis

Treatment of enterococcal endocarditis in patients with history of renal transplantation is complicated. Treatment failure and/or drug toxicities are not uncommon. Treatment with ampicillin and daptomycin in a renal transplant patient has been rarely reported. Here we report a patient who was successfully treated with this novel combination.

Talaromyces marneffei infection in a non-HIV non-endemic population

Introduction

Talaromyces marneffei infection is a systemic mycosis, caused by a dimorphic fungus, an opportunistic pathogen formerly known as Penicillium marneffei. This disease is endemic to Southeast Asia and common in human immunodeficiency virus (HIV) infected patients with low CD4 counts. Here we present a very rarely reported case of Talaromyces marneffei infection in an apparent non-immunosuppressed patient presenting decades later in a non-endemic setting (United States).

Presentation of case

Our patient was a 75-year-old Caucasian Navy veteran, who served in Vietnam as a part of the Swift Boat service in 1966. He presented to his primary care provider with uncontrolled nonproductive cough and abnormal chest computerized tomography. Bronchoscopy specimens showed Talaromyces. He was empirically treated with itraconazole and then switched to voriconazole after confirmation of diagnosis but he later deteriorated was changed to liposomal amphotericin B and isavuconazole. Patient did well for the next 90 days on isavuconazole until the therapy was stopped. Soon after stopping the medication (isavuconazole) his symptoms recurred and ultimately patient expired.

Discussion

Talaromycosis generally presents as pulmonary infection with manifestations similar with other endemic fungi. It is often seen HIV patients with travel to South east Asia. Very rarely this infection is seen and reported in non-immunosuppressed and in non-endemic areas. To date there are 4 well-documented cases among non-HIV, non-endemic population.

Conclusion

Talaromyces can cause infection in non-HIV and non-endemic population and could be an underrecognized cause of pulmonary infections among veterans with even a remote history of exposure to the organism during deployment.

Dipping into the Clostridium difficile pool: Are alcohol-based dispensers fomites for C difficile?

The purpose of this study was to evaluate alcohol-based dispensers as potential fomites for Clostridium difficile. A convenience sample of 120 alcohol-based dispensers was evaluated for the presence of C difficile either by culture or polymerase chain reaction for C difficile toxin. The results demonstrated that C difficile was not cultured, and C difficile toxin was not detected using polymerase chain reaction; however, gram-positive rods, Clostridium perfringens, Pantoea agglomerans, coagulase-negative Staphylococcus, Peptostreptococcus, Bacillus spp, and microaerophilic Streptococcus were present within the overflow basins of the alcohol-based dispensers.

Infection with a chlorophyllic eukaryote after a traumatic freshwater injury

Infections with chlorophyllic algae are uncommon. Invasive infection with Desmodesmus armatus developed in two patients independently after they each sustained a penetrating freshwater injury.

Optical polymers with tunable refractive index for nanoimprint technologies

In order to realize a versatile high throughput production of micro-optical elements, UV-curable polymer composites containing titanium dioxide nanoparticles were prepared and characterized. The composites are based on an industrial prototype epoxy polymer. Titanium dioxide nanoparticles smaller than 10 nm were synthesized by the nonaqueous sol method and in situ sterically stabilized by three different organic surfactants. The composites exhibit high transparency. Distinct alteration of optical transmission properties for visible light and near IR wavelength range could be avoided by adaption of the stabilizing organic surfactant. Most importantly, the refractive index (RI) of the composites that depends on the fraction of incorporated inorganic nanoparticles could be directly tuned. E.g. the RI at a wavelength of 635 nm of a composite containing 23 wt% titanium dioxide nanoparticles is increased to 1.626, with respect to a value of 1.542 for the pure polymer. Furthermore, it could be demonstrated that the prepared inorganic-organic nanocomposites are well suited for the direct fabrication of low-cost micro-optical elements by nanoimprint lithography. A low response of the optical composite properties to temperature treatment up to 220 °C with a shrinkage of only about 4% ensures its application for integrated micro-optical elements in industrial production.

Evaluation of resistless Ga⁺ beam lithography for UV NIL stamp fabrication

This paper presents an alternative rapid prototyping approach for the fabrication of stamps for UV nanoimprint lithography. In this process, areas implanted with gallium serve as an etch mask for the dry etching of quartz. The implantation is performed using a focused ion beam system. To avoid charging of the quartz substrate the use of thin layers of chromium or carbon on the quartz substrate has been evaluated. The resulting quartz structures exhibit very smooth surfaces after dry etching, if the implantation dose is high enough to form a stable etch mask. Furthermore, anisotropic etching could be realized by optimization of a quartz etching process involving C₄F₈ and O₂ after the use of resistless Ga(+) beam lithography. Finally, imprints into a UV curing resist are performed successfully with the manufactured stamps, proving that the presence of Ga rich areas on the stamp is not detrimental to the curing of the resist or the functionality of the anti-sticking layer.

Pleural infections: a 9-year review of bacteriology, case characteristics and mortality

BACKGROUND

Despite advances in medical therapies, pleural infections remain a common disease. The characteristics of this disease seem to change over time, with alterations in patient characteristics and bacteriology. The purpose of this study was to provide a retrospective descriptive analysis of pleural infections during a 9-year period.

METHODS

We performed a single-center retrospective review of all culture-positive pleural infections between January 2000 and December 2008. The primary outcome was assessment of long-term survival and associated independent risk factors affecting survival. Length of survival was determined using the Social Security Death Index. Case characteristics and bacteriology were reviewed for descriptive analysis.

RESULTS

During a 9-year period, 187 culture-positive pleural infections were identified. Review of bacteriology revealed gram-positive cocci as the predominate organisms, most commonly Streptococcus and Staphylococcus. Anaerobes were found in 9.1% of the cases. Independent risk factors associated with risk of death based on multivariable survival analysis were age older than 65, cirrhosis and past and present malignancy. The hospital mortality was 10.7%, and the 1-year, 3-year and 5-year estimated survival rates were 73.8%, 63.3% and 60.6%, respectively.

CONCLUSIONS

Pleural infections continue to remain a major health problem and carry significant morbidly and mortality. The importance of Staphylococcus aureus in this population has yet to be fully examined, and although potentially underestimated in this study, anaerobic infections remain a common pathogen.

Cluster of Mycobacterium fortuitum prosthetic joint infections

Mycobacterium fortuitum is a member of the rapidly growing nontuberculous mycobacteria. Although mortality is rare from M. fortuitum, morbidity depends on the localized site of infection. M. fortuitum is ubiquitous in the environment and has been reported to cause infections of prosthetic devices. There have been seven previously reported cases of prosthetic joint infections due to M. fortuitum. This article presents three additional cases of postoperative joint infections due to M. fortuitum. All three cases were confirmed to be genetically indistinguishable by pulse-field gel electrophoresis. Awareness of its importance is especially noteworthy in the realm of ongoing antibiotic resistance.

An in vitro analysis of microbial transmission during EUS-guided FNA and the utility of sterilization agents

BACKGROUND

The risk of infection and potential microbial transmission with EUS-guided FNA (EUS-FNA) of cystic lesions remains unknown.

OBJECTIVE

We developed an in vitro model to study the incidence of transmucosal microbial transmission during EUS-FNA of cystic lesions and to evaluate the in vitro efficacy of bacteriocidal agent washings of mucosa before FNA under experimental conditions.

DESIGN

Conical tubes, 15 mL, filled with aerobic blood culture bottle media were prepared. Then sterile sections of bovine tripe were fastened over the top of the conical tubes in a sterile fashion (conical tube-tripe unit). FNA was performed with 22-gauge FNA needles. A series of 6 experiments were performed. Ten conical tube-tripe units underwent FNA once through the tripe into the blood culture media to ensure sterility. The surface of 10 conical tube-tripe units were inoculated with 50 microL of a 1.5 x 10(8) 1:1 mixture of Escherichia coli (E coli) and Enterococcus sp, and FNA was performed one time into the blood culture media to ensure contamination (controls). The surface of 40 conical tube-tripe units were inoculated with 50 microL of a 1.5 x 10(8) 1:1 mixture of E coli and Enterococcus sp Each of 4 sets of 10 conical tube-tripe units underwent experimental scenarios that consisted of washings with either 1 mL of 0.5% povidone iodine, chlorhexidine, absolute ethanol, or sterile water. FNA was performed once through the tripe into the blood culture media after washing the surface of the tripe. After each conical tube-tripe unit underwent FNA one time, 1 mL blood culture media was obtained and mixed on pour plate agar media and was incubated along with the conical tubes. Microbial evaluation of the conical tubes that contained the blood culture media and pour plates was performed after 48 hours of incubation.

SETTING

Gastroenterology and Microbiology Departments of Scott White Memorial Hospital and Clinic in Temple, Texas.

INTERVENTIONS

EUS-FNA of cystic lesions.

MAIN OUTCOME MEASUREMENTS

Microbial contamination during EUS-FNA of an in vitro cystic environment.

RESULTS

A control without E coli and Enterococcus sp was with 0% contamination. A control group with E coli and Enterococcus sp was with 100% contamination; sterile water washings, 100% contamination (P = 1.00); iodine washings, 20% contamination (P < .001); chlorhexidine washings, 80% contamination (P = .47); and absolute ethanol washings, 90% contamination (P = 1.00). Results were compared with our control group by statistical tests of proportions by using the Fisher exact test.

CONCLUSIONS

EUS-FNA of sterile cystic lesions resulted in transmucosal microbial contamination. However, our model demonstrated that iodine sterilization of a contaminated mucosal surface produced a very highly statistically significant (P < .001) reduction in the transmission of infectious agents into a sterile environment. This in vitro model could translate into clinical practice by providing evidence that microbial transmission by FNA occurred. The utility of povidone iodine washings could alter procedure methods and patient care.

Clinical significance of Aerococcus urinae: a retrospective review

A retrospective chart review was performed on 54 patients with positive urine cultures during a 1-year period to assess the clinical significance of Aerococcus urinae. Based on predetermined criteria, patients were classified into 2 groups: those with urinary tract infections (UTIs) and those who were considered colonized. The majority of the patients were > or =65 years old and were female. Only 31% of patients with UTI and 45% of colonized patients had A. urinae isolated in pure cultures. Both groups had significant but similar underlying medical conditions, with urologic conditions being predominant. Significantly more patients in the UTI group had urinary catheters (P < .01). No direct complications or invasive disease was recognized in either group regardless of whether patients were treated with antibiotics. Apparently, A. urinae is a relatively avirulent organism when cultured from urine.

Tubo-ovarian abscess caused by Vibrio vulnificus

Vibrio vulnificus is a Gram-negative bacterium that causes an aggressive infection with high mortality, especially in patients with liver disease. Wound infections due to V. vulnificus occur via direct contamination of cutaneous tissues and can include the uterus. We report a case of V. vulnificus tubo-ovarian infection from an unusual method of acquisition in the Gulf of Mexico.

Turicella otitidis mastoiditis in a healthy child

Turicella otitidis, a coryneform bacterium, has been associated with acute otitis media. A 5-year-old girl developed acute mastoiditis. Turicella was isolated from the right and left middle ear fluid.

Intraneuronal ApoE in human visual cortical areas reflects the staging of Alzheimer disease pathology

Alzheimer disease (AD) is marked by progressive loss of cortical neurons with associated cognitive decline. Multiple genetic and environmental factors likely contribute to this progressive loss. Such genetic factors include the polymorphic locus (APOE) that encodes apolipoprotein E (apoE). In order to investigate a possible correspondence between cellular localization of apoE and the neuropathology of AD, we examined the distribution of apoE-immunoreactive neurons in visual cortical areas with different apparent susceptibility to AD neuropathology (areas 17-primary sensory, 18-secondary sensory, and inferior temporal-association cortex) at different stages of AD pathology as described by Braak and Braak. We found that intraneuronal apoE was present at all these stages, however, only in visual cortical regions known to be vulnerable to AD. In the late stages, the laminar distribution of apoE-immunoreactivity matched the distribution of other markers of AD pathology, especially modified tau. These data support previous findings that intraneuronal apoE in neocortex is common in aged, nondemented controls and demonstrate that it may be more common in regions at risk for AD pathology. Thus, intraneuronal accumulation of apoE may be an attribute of cortical neurons that are more vulnerable to age-related injury with the presence of apoE antedating the classical indices of late-onset AD pathology.

Thrombus formation in lymphatic vessels associated with Brugia malayi

Lymph thrombi within affected afferent lymphatic vessels of cats infected with Brugia malayi were examined by scanning electron microscopy. Thrombi were made up of alternating layers of fibrin strands and cells, many of which were intact erythrocytes. The endothelial lining of the vessel wall near the site of thrombus attachment showed transition from normal endothelial cells to a flattened syncytium in which individual endothelial cells could not be distinguished. Imprints of cells, including erythrocytes, were visible in the vessel wall at the point of thrombus attachment. Damage to the endothelial lining may be a factor in the initiation of thrombus formation.