scholarly journals Evaluating the use of a 22-pathogen TaqMan array card for rapid diagnosis of respiratory pathogens in intensive care

2020 ◽  
Vol 69 (7) ◽  
pp. 971-978
Author(s):  
Nick K. Jones ◽  
Andrew Conway Morris ◽  
Martin D. Curran ◽  
Surendra Parmar ◽  
Olajumoke Sule ◽  
...  

Introduction. Pneumonia is highly prevalent in intensive care units (ICUs), with high associated mortality. Empirical treatment prioritizes breadth of coverage while awaiting laboratory diagnosis, often at the expense of antimicrobial stewardship. Microarrays use multiple parallel polymerase chain reactions to enable a rapid syndromic approach to laboratory diagnosis. Aim. To evaluate the clinical and laboratory implications of introducing a bespoke 22-pathogen TaqMan Array Card (TAC) for rapid pathogen detection in deep respiratory samples from adult ICUs. Methodology. TAC results from all ICU patients prospectively tested over a 9-month period at Cambridge’s Clinical Microbiology and Public Health Laboratory were compared to those of corresponding conventional microbiological assays (culture-, PCR- or serology-based) in terms of result agreement and time-to-result availability. Clinical impact was assessed by retrospective review of medical records. Results. Seventy-one patients were included [45 (63 %) male, median age 59). Overall result agreement was 94 %, with TAC detecting more pathogens than conventional methods. TAC detected Streptococcus pneumoniae more readily than culture (7 vs 0 cases; P=0.02). TAC did not detect Aspergillus spp. in eight culture- or galactomannan-positive cases. The median turnaround time (1 day) was significantly shorter than that of bacterial/fungal culture, Pneumocystis jirovecii PCR and galactomannan testing (each 3 days; P<0.001), atypical bacteria serology (13 days; P<0.001) and Mycobacterium tuberculosis culture (46 days; P<0.001). Earlier result availability prompted discontinuation of unnecessary antimicrobials in 15/71 (21 %) cases, but had no bearing on patient isolation/deisolation. Conclusion. TAC provided greater overall yield of pathogen detection and faster turnaround times, permitting earlier discontinuation of unnecessary antimicrobials.

2021 ◽  
Vol 3 (11) ◽  
Author(s):  
Max Roberto Batista Araújo ◽  
Mireille Ângela Bernardes Sousa ◽  
Luisa Ferreira Seabra ◽  
Letícia Aparecida Caldeira ◽  
Carmem Dolores Faria ◽  
...  

Diphtheria is a potentially fatal infection, mostly caused by diphtheria toxin (DT)-producing Corynebacterium diphtheriae strains. During the last decades, the isolation of DT-producing C. diphtheriae strains has been decreasing worldwide. However, non-DT-producing C. diphtheriae strains emerged as causative agents of cutaneous and invasive infections. Although endemic in countries with warm climates, cutaneous diphtheria is rarely reported in Brazil. Presently, an unusual case of skin lesion in a Brazilian elderly diabetic patient infected by a penicillin-resistant non-DT-producing C. diphtheriae strain was reported. Laboratory diagnosis included mass spectrometry and multiplex PCR analyses. Since cutaneous diphtheria lesions are possible sources of secondary diphtheria cases and systemic diseases and considering that penicillin is the first line of antimicrobial agent for the treatment of these infections, the detection of penicillin-resistant strains of diphtheria bacilli should be a matter of concern. Thus, cases similar to the presently reported should be appropriately investigated and treated, particularly in patients with risk factor (s) for the development of C. diphtheriae invasive infections, such as diabetes. Moreover, health professionals must be aware of the presence of C. diphtheriae in cutaneous lesions of lower limbs, a common type of morbidity in diabetic patients, especially in tropical and subtropical countries.


2020 ◽  
Author(s):  
Dodi Safari ◽  
Feby Valentiya ◽  
Korrie Salsabila ◽  
Wisiva Tofriska Paramaiswari ◽  
Wisnu Tafroji ◽  
...  

Streptococcus pneumoniae produces pili that function as adherence factors to bind to epithelial cells in the human upper respiratory tract. In this study, we investigated the prevalence of pilus islets (PIs) in S. pneumoniae strains carried by healthy children below 5 years of age prior to pneumococcal vaccination in 2012 in Lombok Island, Indonesia. In all, 347 archived S. pneumoniae isolates were screened using polymerase chain reactions for the presence of rrgC and pitB genes representing pilus islet 1 (PI-1) and pilus islet 2 (PI-2), respectively. We found that 40 isolates (11.5 %) contained the PI genes: 5.2% carried both PI-1 and PI-2, and 3.5 and 2.9% carried PI-1 and PI-2, respectively. Furthermore, we found that most of the strains carrying either of the PIs belonged to the vaccine serotypes 19F and 19A and were less susceptible to chloramphenicol and tetracycline.


2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Duong Bich Thuy ◽  
James Campbell ◽  
Cao Thu Thuy ◽  
Nguyen Van Minh Hoang ◽  
Phat Voong Vinh ◽  
...  

Pre-existing colonization with Staphylococcus aureus or Klebsiella pneumoniae has been found to increase the risk of infection in intensive care patients. We previously conducted a longitudinal study to characterize colonization of these two organisms in patients admitted to intensive care in a hospital in southern Vietnam. Here, using genomic and phylogenetic analyses, we aimed to assess the contribution these colonizing organisms made to infections. We found that in the majority of patients infected with S. aureus or K. pneumoniae , the sequence type of the disease-causing (infecting) isolate was identical to that of corresponding colonizing organisms in the respective patient. Further in-depth analysis revealed that in patients infected by S. aureus ST188 and by K. pneumoniae ST17, ST23, ST25 and ST86, the infecting isolate was closely related to and exhibited limited genetic variation relative to pre-infection colonizing isolates. Multidrug-resistant S. aureus ST188 was identified as the predominant agent of colonization and infection. Colonization and infection by K. pneumoniae were characterized by organisms with limited antimicrobial resistance profiles but extensive repertoires of virulence genes. Our findings augment the understanding of the link between bacterial colonization and infection in a low-resource setting, and could facilitate the development of novel evidence-based approaches to prevent and treat infections in high-risk patients in intensive care.


2021 ◽  
Author(s):  
Rama Chaudhry ◽  
K. Sreenath ◽  
E. V. Vinayaraj ◽  
Biswajeet Sahoo ◽  
M. R. Vishnu Narayanan ◽  
...  

We report co-infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Mycoplasma pneumoniae in a patient with pneumonia in India. Atypical bacterial pathogens causing community-acquired pneumonia may share similar clinical presentations and radiographic features with SARS-CoV-2 making a thorough differential diagnosis essential. The co-infection of SARS-CoV-2 and M. pneumoniae is infrequently reported in the literature. Broader testing for common respiratory pathogens should be performed in severe COVID-19 cases to rule out other concurrent infections. Early identification of co-existing respiratory pathogens could provide pathogen-directed therapy, and can save patient lives during the ongoing COVID-19 outbreak.


2014 ◽  
Vol 64 (Pt_11) ◽  
pp. 3877-3884 ◽  
Author(s):  
Celine De Maesschalck ◽  
Filip Van Immerseel ◽  
Venessa Eeckhaut ◽  
Siegrid De Baere ◽  
Margo Cnockaert ◽  
...  

Strains LMG 27428T and LMG 27427 were isolated from the caecal content of a chicken and produced butyric, lactic and formic acids as major metabolic end products. The genomic DNA G+C contents of strains LMG 27428T and LMG 27427 were 40.4 and 38.8 mol%. On the basis of 16S rRNA gene sequence similarity, both strains were most closely related to the generically misclassified Streptococcus pleomorphus ATCC 29734T. Strain LMG 27428T could be distinguished from S. pleomorphus ATCC 29734T based on production of more lactic acid and less formic acid in M2GSC medium, a higher DNA G+C content and the absence of activities of acid phosphatase and leucine, arginine, leucyl glycine, pyroglutamic acid, glycine and histidine arylamidases, while strain LMG 27428 was biochemically indistinguishable from S. pleomorphus ATCC 29734T. The novel genus Faecalicoccus gen. nov. within the family Erysipelotrichaceae is proposed to accommodate strains LMG 27428T and LMG 27427. Strain LMG 27428T ( = DSM 26963T) is the type strain of Faecalicoccus acidiformans sp. nov., and strain LMG 27427 ( = DSM 26962) is a strain of Faecalicoccus pleomorphus comb. nov. (type strain LMG 17756T = ATCC 29734T = DSM 20574T). Furthermore, the nearest phylogenetic neighbours of the genus Faecalicoccus are the generically misclassified Eubacterium cylindroides DSM 3983T (94.4 % 16S rRNA gene sequence similarity to strain LMG 27428T) and Eubacterium biforme DSM 3989T (92.7 % 16S rRNA gene sequence similarity to strain LMG 27428T). We present genotypic and phenotypic data that allow the differentiation of each of these taxa and propose to reclassify these generically misnamed species of the genus Eubacterium formally as Faecalitalea cylindroides gen. nov., comb. nov. and Holdemanella biformis gen. nov., comb. nov., respectively. The type strain of Faecalitalea cylindroides is DSM 3983T = ATCC 27803T = JCM 10261T and that of Holdemanella biformis is DSM 3989T = ATCC 27806T = CCUG 28091T.


2015 ◽  
Vol 65 (Pt_6) ◽  
pp. 1819-1824 ◽  
Author(s):  
Sooyeon Park ◽  
Ji-Min Park ◽  
Chul-Hyung Kang ◽  
Song-Gun Kim ◽  
Jung-Hoon Yoon

A Gram-stain-negative, non-motile, aerobic and pleomorphic bacterium, designated BS-W13T, was isolated from a tidal flat on the South Sea, South Korea, and its taxonomic position was investigated using a polyphasic approach. Strain BS-W13T grew optimally at 25 °C, at pH 7.0–8.0 and in the presence of 1.0–2.0 % (w/v) NaCl. Neighbour-joining and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences showed that strain BS-W13T clustered with the type strain of Seohaeicola saemankumensis , showing the highest sequence similarity (95.96 %) to this strain. Strain BS-W13T exhibited 16S rRNA gene sequence similarity values of 95.95, 95.91, 95.72 and 95.68 % to the type strains of Sulfitobacter donghicola , Sulfitobacter porphyrae , Sulfitobacter mediterraneus and Roseobacter litoralis , respectively. Strain BS-W13T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the major fatty acid. The polar lipid profile of strain BS-W13T, containing phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid as major components, was distinguishable from those of some phylogenetically related taxa. The DNA G+C content of strain BS-W13T was 58.1 mol%. The phylogenetic data and differential chemotaxonomic and other phenotypic properties revealed that strain BS-W13T constitutes a novel genus and species within family Rhodobacteraceae of the class Alphaproteobacteria , for which the name Pseudoseohaeicola caenipelagi gen. nov., sp. nov. is proposed. The type strain is BS-W13T ( = KCTC 42349T = CECT 8724T).


2013 ◽  
Vol 63 (Pt_3) ◽  
pp. 1149-1154 ◽  
Author(s):  
Varsha Kale ◽  
Snædís H. Björnsdóttir ◽  
Ólafur H. Friðjónsson ◽  
Sólveig K. Pétursdóttir ◽  
Sesselja Ómarsdóttir ◽  
...  

A thermophilic, aerobic, Gram-stain-negative, filamentous bacterium, strain PRI-4131T, was isolated from an intertidal hot spring in Isafjardardjup, NW Iceland. The strain grew chemo-organotrophically on various carbohydrates. The temperature range for growth was 40–65 °C (optimum 55 °C), the pH range was pH 6.5–9.0 (optimum pH 7.0) and the NaCl range was 0–3 % (w/v) (optimum 0.5 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain PRI-4131T represented a distinct lineage within the class Caldilineae of the phylum Chloroflexi. The highest levels of sequence similarity, about 91 %, were with Caldilinea aerophila STL-6-O1T and Caldilinea tarbellica D1-25-10-4T. Fermentative growth was not observed for strain PRI-4131T, which, in addition to other characteristics, distinguished it from the two Caldilinea species. Owing to both phylogenetic and phenotypic differences from the described members of the class Caldilineae , we propose to accommodate strain PRI-4131T in a novel species in a new genus, Litorilinea aerophila gen. nov., sp. nov. The type strain of Litorilinea aerophila is PRI-4131T ( = DSM 25763T  = ATCC BAA-2444T).


2012 ◽  
Vol 62 (Pt_11) ◽  
pp. 2589-2592 ◽  
Author(s):  
Hyo-Jin Lee ◽  
Song-Ih Han ◽  
Kyung-Sook Whang

A novel actinobacterium, designated strain BR-34T, was isolated from rhizosphere soil of bamboo (Phyllostachys nigro var. henonis) sampled in Damyang, Korea. The strain was found to have morphological and chemotaxonomic characteristics typical of the genus Catenulispora . The strain contained iso-C16 : 0 as the major fatty acid and MK-9(H4), MK-9(H6) and MK-9(H8) as major isoprenoid quinones. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain BR-34T formed a cluster separate from members of the genus Catenulispora and was related most closely to Catenulispora acidiphila ID139908T (97.4 % similarity), Catenulispora rubra Aac-30T (97.3 %), Catenulispora yoronensis TT N02-20T (97.3 %) and Catenulispora subtropica TT 99-48T (97 %). However, the level of DNA–DNA relatedness between strain BR-34T and C. acidiphila ID139908T was only 45.32 %. Based on DNA–DNA relatedness, morphological and phenotypic data, strain BR-34T could be distinguished from the type strains of phylogenetically related species. It is therefore considered to represent a novel species of the genus Catenulispora , for which the name Catenulispora graminis sp. nov. is proposed. The type strain is BR-34T ( = KACC 15070T = NBRC 107755T).


2013 ◽  
Vol 63 (Pt_9) ◽  
pp. 3280-3286 ◽  
Author(s):  
Iris Kuo ◽  
Jimmy Saw ◽  
Durrell D. Kapan ◽  
Stephanie Christensen ◽  
Kenneth Y. Kaneshiro ◽  
...  

Strain IK-1T was isolated from decaying tissues of the shrub Wikstroemia oahuensis collected on O‘ahu, Hawai‘i. Cells were rods that stained Gram-negative. Gliding motility was not observed. The strain was oxidase-negative and catalase-positive. Zeaxanthin was the major carotenoid. Flexirubin-type pigments were not detected. The most abundant fatty acids in whole cells of IK-1T grown on R2A were iso-C15 : 0 and one or both of C16 : 1ω7c and C16 : 1ω6c. Based on comparisons of the nucleotide sequence of the 16S rRNA gene, the closest neighbouring type strains were Flavobacterium rivuli WB 3.3-2T and Flavobacterium subsaxonicum WB 4.1-42T, with which IK-1T shares 93.84 and 93.67 % identity, respectively. The G+C content of the genomic DNA was 44.2 mol%. On the basis of distance from its nearest phylogenetic neighbours and phenotypic differences, the species Flavobacterium akiainvivens sp. nov. is proposed to accommodate strain IK-1T ( = ATCC BAA-2412T = CIP 110358T) as the type strain. The description of the genus Flavobacterium is emended to reflect the DNA G+C contents of Flavobacterium akiainvivens IK-1T and other species of the genus Flavobacterium described since the original description of the genus.


2015 ◽  
Vol 65 (Pt_2) ◽  
pp. 516-521 ◽  
Author(s):  
Gaiyun Zhang ◽  
Yubian Zhang ◽  
Xijie Yin ◽  
Shuang Wang

A Gram-staining-positive, aerobic, motile and non-spore-forming actinobacteria, designated strain F10T, was isolated from a deep-sea sediment of the western Pacific Ocean. Phylogenetic and phenotypic properties of the organism supported that it belonged to the genus Nesterenkonia . Strain F10T shared highest 16S rRNA gene sequence similarity of 96.8 % with Nesterenkonia aethiopica DSM 17733T, followed by Nesterenkonia xinjiangensis YIM 70097T (96.7 %) and Nesterenkonia alba CAAS 252T (96.6 %). The organism grew at 4–50 °C, at pH 7.0–12.0 and in the presence of 0–12 % (w/v) NaCl, with optimal growth occurring at 40 °C, at pH 9.0 and in the presence of 1 % (w/v) NaCl. The peptidoglycan type was A4(alpha), l-Lys–Gly–l-Glu. The polar lipid profile of strain F10T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, two unknown glycolipids and two unknown lipids. The isolate contained MK-9 (92 %) and MK-8 (5.8 %) as the major components of the menaquinone system, and anteiso-C17 : 0 (50.9 %) and anteiso-C15 : 0 (29.8 %) as the predominant fatty acids. The G+C content of the genomic DNA of strain F10T was 66.2 mol%. Based on phenotypic, genotypic and phylogenetic analyses, strain F10T represents a novel species of the genus Nesterenkonia for which the name Nesterenkonia alkaliphila sp. nov. is proposed. The type strain is F10T ( = LMG 28112T = CGMCC 1.12781T = JCM 19766T = MCCC 1A09946T).


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