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Many bacterial typing methods are specific for one species only, time-consuming, or poorly reproducible. DiversiLab (DL; bioMérieux) potentially overcomes these limitations. In this study, we evaluated the DL system for the identification of hospital outbreaks of a number bacterial species. Appropriately typed clinical isolates were tested with DL. DL typing agreed with pulsed-field gel electrophoresis (PFGE) for Acinetobacter (n ‫؍‬ 26) and Stenotrophomonas maltophilia (n ‫؍‬ 13) isolates. With two exceptions, DL typing of Klebsiella isolates (n ‫؍‬ 23) also correlated with PFGE, and in addition, PFGE-nontypeable (PFGE-NT) isolates could be typed. Enterobacter (n ‫؍‬ 28) results also correlated with PFGE results; also, PFGE-NT isolates could be clustered. In a larger study (n ‫؍‬ 270), a cluster of 30 isolates was observed that could be subdivided by PFGE. The results for Escherichia coli (n ‫؍‬ 38) correlated less well with an experimental multilocus variable number of tandem repeats analysis (MLVA) scheme. Pseudomonas aeruginosa (n ‫؍‬ 52) showed only a limited number of amplification products for most isolates. When multiple Pseudomonas isolates were assigned to a single type in DL, all except one showed multiple multilocus sequence types. Methicillin-resistant Staphylococcus aureus generally also showed a limited number of amplification products. Isolates that belonged to different outbreaks by other typing methods, including PFGE, spa typing, and MLVA, were grouped together in a number of cases. For Enterococcus faecium, the limited variability of the amplification products obtained made interpretation difficult and correlation with MLVA and esp gene typing was poor. All of the results are reflected in Simpson's index of diversity and adjusted Rand's and Wallace's coefficients. DL is a useful tool to help identify hospital outbreaks of Acinetobacter spp., S. maltophilia, the Enterobacter cloacae complex, Klebsiella spp., and, to a somewhat lesser extent, E. coli. In our study, DL was inadequate for P. aeruginosa, E. faecium, and MRSA. However, it should be noted that for the identification of outbreaks, epidemiological data should be combined with typing results.

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We evaluated the use of a novel multiple-locus variable-number tandem-repeat analysis (MLVA) method for typing of human Staphylococcus aureus. For a total of 150 clinical isolates, MLVA demonstrated the highest discriminatory power. MLVA correctly assigned isolates to outbreaks or identified isolates as unlinked. MLVA is a rapid and simple method for the epidemiological typing of S. aureus.Pulsed-field gel electrophoresis (PFGE) is considered the gold standard method for the typing of Staphylococcus aureus isolates (1). Other commonly used typing schemes include multilocus sequence typing (MLST) and spa typing (www.mlst .net and www.spaserver.ridom.de) (2, 7). Recently, a method based on the unique lengths of the intergenic regions containing repetitive DNA loci (5,8,9,12,13), known as multiplelocus variable-number tandem-repeat analysis (MLVA), was introduced and described. Using this method, Hardy et al. described an MLVA scheme based on seven variable-number tandem repeats in S. aureus, termed staphylococcal interspersed repeat units (SIRUs) (5, 6). All of these methods have a number of drawbacks; most importantly, they are either fingerprinting methods, which are difficult to compare, or library typing methods lacking discriminatory power (3, 9, 10, 12, 13). We therefore developed a character-based MLVA scheme for human S. aureus that is based on the number of repeats of each locus, i.e., the allelic profile, which can then be used in combination with spa typing. A similar approach has already been reported for bovine S. aureus (4).Our scheme was first tested using 100 European clinical human S. aureus isolates: 25 methicillin-susceptible and 75 methicillin-resistant isolates obtained between 1997 and 2004 were selected from the ENARE collection at the University Medical Centre Utrecht (UMCU), The Netherlands. These 100 specimens represented 35 MLST types and were well distributed throughout the S. aureus population (data not shown). MLVA typing was performed by using SIRU01, -05, -07, -13, -15, -16, and -21 (representing the spa gene) and sspA (5, 10). Each amplification was performed separately. The PCR products of SIRU01, -05, -07, -13, -15, -16, and sspA were analyzed on 2% agarose gel, while the SIRU21 PCR product was run on a 3% agarose gel. The number of repeat units (RUs) in each locus was determined by subtracting the sizes of the flanking regions from the size of the amplicon and then dividing the difference by the size of the repeat (Table 1). The result was then rounded to the nearest integer value.The MLVA showed the numbers of RUs to range from 0 to 26 (Table 1). SIRU16 and sspA were excluded from further study due to a lack of variation in RUs. Seventy-three isolates yielded complete MLVA profiles, and 27 isolates yielded partial profiles. The unamplified loci of the latter isolates were assigned the number 999. Combinations of RUs from SIRU01, -05, -07, -13, -15, and -21 yielded number strings that were considered to be the allelic profiles. An MLVA type (MT) was assigned to each of these pro...

Abstract— Background: A human severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to be responsible for coronavirus disease 2019 (COVID-19). Pulmonary complications has been considered as the classical clinical manifestations until symptoms on the extra-pulmonary organs may also occur recently, which might be linked to the presence of angiotensin-converting enzyme 2 (ACE2) receptor. Objective: This article evaluates clinical manifestation of COVID-19 and the presence of ACE2 receptor by looking at its interaction to SARS-CoV-2. Methods: 27 articles in English have been selected through search engine PubMed and Google Scholar by using specific keywords. These articles include research journals, case report, systematic review and meta-analysis, and textbooks. Result: Pathogenesis of COVID-19 begins with the binding of spike protein SARS-CoV-2 to ACE2 receptor of host cells. Clinical manifestation of COVID-19 is no longer limited to the pulmonary system but also extra-pulmonary systems since ACE2 receptor abundantly distributed on the other organs. Further, genetic variations of region binding protein of viral spike protein and ACE2 receptor may predispose clinical manifestation of COVID19.  Conclusions: Dynamic interplay between SARS-CoV-2 and receptor ACE2 has great implication to the clinical symptoms. Genetic variation of spike protein SARS-CoV-2 play role not only for cross transmission but also its virulence, while genetic variation of human receptor ACE2 influences its susceptibility or resistance against the infection. Keywords: ACE2 receptor, Coronavirus Diseases-19, clinical manifestation, SARS-CoV-2, genetic variation. Abstrak— Virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) merupakan penyebab utama dari coronavirus disease 2019 (COVID-19). Komplikasi pernapasan diangap sebagai gejala klinis klasik hingga akhirnya timbul berbagai manifestasi klinis di organ lain sebagai gejala awal COVID19. Hal ini kemudian dihubungkan dengan reseptor angiotensin-converting enzyme 2 (ACE2). Artikel ini mengevaluasi manifestasi klinis yang disebabkan  interaksi antara reseptor ACE2 dan SARS-CoV-2. PubMed dan Google Scholar digunakan untuk mencari artikel dengan kata kunci yang spesifik untuk COVID-19, SARS-CoV-2, reseptor ACE2, variasi genetik, dan manifestasi klinisnya. Dua puluh tujuh artikel berbahasa Inggris yang digunakan termasuk jurnal penelitian, laporan kasus, systematic review, meta-analysis, dan buku teks. Patogenesis COVID19 dimulai dengan ikatan protein Spike SARS-CoV-2 dan reseptor ACE2. Studi memperlihatkan bahwa reseptor ACE2 ditemui di berbagai jaringan/organ selain organ sistem respirasi sehingga memperlihatkan gejala klinis yang berbeda. Selain itu variasi genetik yang terdapat pada protein spike dari virus dan reseptor ACE2 juga merupakan faktor penting pada terjadinya COVID19. Penulis menyimpulkanbahwa dinamika interaksi antara reseptor ACE2 dan protein spike SARS-CoV-2 termasuk variasi genetic, keduanya memegang peranan penting terhadap suseptibilitas/resistensi dan manifestasi klinis COVID19. Kata kunci: Coronavirus Diseases-19, manifestasi klinis,  reseptor ACE2, SARS-CoV-2, variasi genetik.

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