Drug Sensitivity Patterns Research Articles

Bacteriological Profiles with Antibiotic Susceptibility Pattern in Different Clinical Specimens of Specialized Neuroscience Hospital of Bangladesh

Background: Throughout the world multi-drug resistant hospital acquired infections (HAI) are one of the leading causes of deaths and morbidity amongst hospitalized patients.
 Objective: The aim of study was to identify prevalence and variations of predominant microorganisms and their drug sensitivity and resistance pattern in a tertiary care public hospital, Dhaka, Bangladesh.
 Methodology: The study was conducted in Intensive Care Unit (ICU), High Dependency Unit (HDU), Post-operative ward and general wards of a tertiary care publicNeuro- hospital in Dhaka during 1st January, 2017 to 31st December, 2018. Patients admitted in any of the four units (ICU, HDU, Post-operative and general wards) of the hospital who were clinically suspected of having acquired any infection after 48 hours of admission to the ICUs were included. Depending on the clinical suspicion laboratory samples were collected from the patients. Samples were subjected to the testing and antibiotic sensitivity.
 Results: A total number of total 1672 samples from these patients yielded clinically relevant microorganisms. Of these samples, 273 were respiratory specimens were tracheal aspirate; 537 were urine; 377 were blood; 396 were cerebrospinal fluids; and 82 were other clinical samples. More than two-third samples were growth negative (71.4%) and only one-thirdsamples (28.6%) were growth positive. Maximum growth negative in blood samples and about half of samples of urine and tracheal aspirates were growth negative. About 80% were Gram-negative bacteria like Escherichia coli, Pseudomonas spp., Klebsiella whereas gram-positive organisms were about 20%. Most of the pathogens were Multi-drug resistance.
 Conclusion: Among HAIs Multidrug-resistant Gram-negative bacteria are the main challenge. Regular updating resistance of microbial are needed to develop antibiotic guideline to combat these infections and reduce morbidity and mortality.
 Journal of National Institute of Neurosciences Bangladesh, 2020;6(2): 82-86

Recent Trend of Bacteriological Profile and Drug Sensitivity Pattern of Neonatal Septicemia in A Tertiary Care Hospital in Bangladesh

Background : In Bangladesh about 67% of under-five mortality is neonatal mortality. One of three major causes of neonatal morbidity and mortality is septicemia. Recently there is increasing incidence of multidrug resistant neonatal organisms which is alarming.
 Objective : The aim of this study was to see the bacteriological profile and drug sensitivity pattern of neonatal septicemia.
 Methods : This prospective observational study was done in Dhaka Shishu (children) Hospital over one-year period from June 2018 to May 2019. The admitted neonates were suspected as neonatal septicemia considering the risk factors, clinical profile and investigations (CBC, CRP etc.). Blood from all suspected neonatal septicemia cases were sent for culture and drugs sensitivity along with others necessary investigations. Then data was analyzed with SPSS version-20.
 Results : Among the suspected cases only 111(10%) patients were culture positive. Preterm were 77(69%) and term 34(31%). One hundred six cases (95%) had sepsis with gram negative organisms and 5(5%) had sepsis with gram positive organisms with more predominant of Klebsiella (76,68%) followed by Acinetobacter (16,14%), Pseudomonas (6,5%), Escherichia coli (3,3%). Majority 80 (72%) cases had Early onset neonatal sepsis (EONS). Klebsiella (57, 51%) was more common organism followed by Acinetobacter (11,10 %) causing EONS and in late onset neonatal sepsis (LONS), similar type of causative organism were found. Ampicillin, Gentamicin and Ceftazidime were mostly resistance to gram negative organisms - 104(94%), 99(89%) and 93(84%) respectively. Besides these, Amikacin (104,94%), Imipenem (85, 77%) and Ciprofloxacin (73, 66%) were more resistance. Klebsiella in 17 cases and Acinetobacter in 4 cases were resistant to all commonly used antibiotics.
 Conclusion : Klebsiella followed by Acinetobacter and Pseudomonas are now common pathogens of neonatal septicemia found in this study. Ampicillin, Gentamicin and Ceftazidime are more resistant to most of the organisms causing neonatal sepsis. Imipenem is alarmingly resistant. In 19% cases, the organisms are resistance to all commonly used antibiotics.
 Northern International Medical College Journal Vol. 11 No. 1 July 2019, Page 427-431

Identification of proteasome inhibitors using analysis of gene expression profiles

Inhibitors of the 20S proteasome such as bortezomib (Velcade®) and carfilzomib (Kypriolis®) are in clinical use for the treatment of patients with multiple myeloma and mantle cell lymphoma. In an attempt to identify novel inhibitors of the ubiquitin-proteasome system (UPS) we used the connectivity map (CMap) resource, based on alterations of gene expression profiles by perturbagens, and performed COMPARE analyses of drug sensitivity patterns in the NCI60 panel. Cmap analysis identified a large number of small molecules with strong connectivity to proteasome inhibition, including both well characterized inhibitors of the 20S proteasome and molecules previously not described to inhibit the UPS. A number of these compounds have been reported to be cytotoxic to tumor cells and were tested for their ability to decrease processing of proteasome substrates. The antibiotic thiostrepton and the natural products celastrol and curcumin induced strong accumulation of polyubiquitinated proteasome substrates in exposed cells. Other compounds elicited modest increases of proteasome substrates, including the protein phosphatase inhibitor BCI–Cl and the farnesyltransferase inhibitor manumycin A, suggesting that these compounds inhibit proteasome function. Induction of chaperone expression in the absence of proteasome inhibition was observed by a number of compounds, suggesting other effects on the UPS. We conclude that the combination of bioinformatic analyses and cellular assays resulted in the identification of compounds with potential to inhibit the UPS.

Correlating Clinical and Genomic Features with Ex Vivo Drug Sensitivity in Patients with Myelodysplastic Syndromes and Related Myeloid Neoplasms

Background Myelodysplastic syndromes (MDS) are heterogeneous myeloid neoplasms characterized by ineffective hematopoiesis, dysplasia, cytopenias, and a variable risk of progression to acute myeloid leukemia (AML). The biologic heterogeneity of MDS and related myeloid neoplasms relates to the genomic complexity of these disorders with different combinations of cytogenetic abnormalities and mutations associated with distinct clinical phenotypes. Ex vivo drug sensitivity screening (DSS) is a promising tool that may inform personalized therapy in MDS, particularly in patients refractory to standard therapies such as hypomethylating agents (HMAs). We report our updated experience using a fully automated ex vivo DSS platform in 64 patients with MDS and related myeloid neoplasms and identify correlations between clinical and genomic features and ex vivo drug sensitivity. Methods Patients: Patients were evaluated at the Stanford MDS Center between September 2016 and May 2020 and had a diagnosis of MDS, MDS/MPN, or secondary AML. Bone marrow (BM) aspirate and peripheral blood (PB) samples were procured for mutation testing (164-gene panel) and ex vivo DSS (Notable Labs, Foster City, CA). Ex vivo DSS: Fresh BM aspirate and PB specimens were RBC-lysed and resuspended in serum-free media with cytokines as previously described (Spinner et al, Blood Adv 2020;4(12):2768-78). Samples were plated in 384-well microtiter plates and screened against a collection of up to 74 drugs and 36 drug combinations in triplicate. Specimens were treated for 72 hours and assayed using high-throughput, multi-parametic flow cytometry, gating on the blast population (expressing CD34, CD33, and/or HLA-DR) to assess for blast viability. Patient clustering & statistical analysis: The Euclidean distance metric and Ward minimum variance method were used to identify patient clusters with distinct ex vivo drug sensitivity patterns. A 1-way repeated measures ANOVA was used to identify drug classes with variable sensitivity across clusters and to identify associations between clusters and clinical variables, including blast count, mutations and cytogenetic groups, IPSS-R risk group, and prior HMA exposure. A generalized estimation equation model was used to identify associations between mutations and ex vivo drug sensitivity. Results Ex vivo DSS was performed in 64 patients with myeloid neoplasms including 43 with MDS (67%), 11 with MDS/MPNs (17%), and 10 with secondary AML (16%). The median age was 75 years (range 23-90) and 78% were male. The majority of patients had higher risk disease with IPSS-R >3.5 (66%), excess blasts (58%), and adverse cytogenetics or mutations (53%) by IPSS-R or the ELN classification. Patients had a median of 2 pathogenic mutations (range 0-7), with the most frequent including TET2, ASXL1, DNMT3A, SF3B1, RUNX1, STAG2, SRSF2, NRAS, KRAS, BCOR, TP53, and EZH2. The majority of patients (64%) had prior HMA exposure. Ex vivo DSS defined three distinct patient clusters with differential sensitivity to numerous drug classes (Figure 1). Cluster 1 (N=13) demonstrated the greatest ex vivo sensitivity to HMAs, HMA/venetoclax combinations, cytotoxic agents, kinase inhibitors, mTOR inhibitors, HDAC inhibitors, and PARP inhibitors, while cluster 3 (N=19) demonstrated the greatest ex vivo resistance (p<0.0001 for all comparisons). Correlating clinical variables with drug sensitivity clusters, only IPSS-R score differed significantly among clusters, with fewer higher risk patients in cluster 3 (p=0.02). Correlating specific mutations with ex vivo drug sensitivity, STAG2 mutations were associated with greater ex vivo sensitivity to HMAs (p=0.002), HMA/venetoclax combinations (p=0.003), kinase inhibitors (p=0.002), and PARP inhibitors (p=0.003). TP53 mutations were associated with greater ex vivo sensitivity to proteasome inhibitors (p=0.0002). Conclusions Ex vivo DSS defined distinct patient clusters with differential sensitivity to numerous drug classes. Specific mutations, such as STAG2 and TP53, were associated with greater ex vivo sensitivity to specific drug classes. A larger sample size is needed to evaluate combinations of mutations and better define associations between genotype and drug sensitivity phenotype. Ultimately, combining both genomics and functional screening may further refine personalized therapy selection for patients with MDS and related myeloid neoplasms. Figure Disclosures Spinner: Notable Labs: Honoraria. Schaffert:Notable Labs: Current Employment. Aleshin:Notable Labs: Consultancy. Santaguida:Notable Labs: Current Employment. Tada:Notable Labs: Current Employment, Current equity holder in private company. Greenberg:BMS: Research Funding; Aprea: Research Funding; H3 Biotech: Research Funding; Notable Labs: Research Funding.

Differential virulence of Trypanosoma brucei rhodesiense isolates does not influence the outcome of treatment with anti-trypanosomal drugs in the mouse model.

We assessed the virulence and anti-trypanosomal drug sensitivity patterns of Trypanosoma brucei rhodesiense (Tbr) isolates in the Kenya Agricultural and Livestock Research Organization-Biotechnology Research Institute (KALRO-BioRI) cryobank. Specifically, the study focused on Tbr clones originally isolated from the western Kenya/eastern Uganda focus of human African Trypanosomiasis (HAT). Twelve (12) Tbr clones were assessed for virulence using groups(n = 10) of Swiss White Mice monitored for 60 days post infection (dpi). Based on survival time, four classes of virulence were identified: (a) very-acute: 0-15, (b) acute: 16-30, (c) sub-acute: 31-45 and (d) chronic: 46-60 dpi. Other virulence biomarkers identified included: pre-patent period (pp), parasitaemia progression, packed cell volume (PCV) and body weight changes. The test Tbr clones together with KALRO-BioRi reference drug-resistant and drug sensitive isolates were then tested for sensitivity to melarsoprol (mel B), pentamidine, diminazene aceturate and suramin, using mice groups (n = 5) treated with single doses of each drug at 24 hours post infection. Our results showed that the clones were distributed among four classes of virulence as follows: 3/12 (very-acute), 3/12 (acute), 2/12 (sub-acute) and 4/12 (chronic) isolates. Differences in survivorship, parasitaemia progression and PCV were significant (P<0.001) and correlated. The isolate considered to be drug resistant at KALRO-BioRI, KETRI 2538, was confirmed to be resistant to melarsoprol, pentamidine and diminazene aceturate but it was not resistant to suramin. A cure rate of at least 80% was achieved for all test isolates with melarsoprol (1mg/Kg and 20 mg/kg), pentamidine (5 and 20 mg/kg), diminazene aceturate (5 mg/kg) and suramin (5 mg/kg) indicating that the isolates were not resistant to any of the drugs despite the differences in virulence. This study provides evidence of variations in virulence of Tbr clones from a single HAT focus and confirms that this variations is not a significant determinant of isolate sensitivity to anti-trypanosomal drugs.

An Observational Study to Collect and Assess Tissue Samples from Subjects with One of Three Neoplastic Conditions (ANSWer)

Background: Multiple studies have demonstrated that established human cancer cell lines are inadequate to model intra- and inter-patient tumor heterogeneity and resulting mechanisms of disease resistance and progression. Ex vivo drug sensitivity screening (DSS) on primary patient samples may provide a unique approach to overcome these limitations, unlocking insights into drug resistance and identify novel combination therapies that overcome resistance. Notable Labs has built an automated, flow-cytometry-based high-throughput DSS platform that enables testing hundreds of drugs and combinations on individual patient samples at scale. In addition, custom-built software facilitates data analysis and delivery of results within clinically actionable turnaround times.1 This technology platform is in use in the ANSWer study to obtain evidence for potential clinical utility of DSS in clinical practice and management of hematologic malignancies. Study Design and Methods: This is a prospective, multicenter, observational study with collection of de-identified biospecimens with matched clinical data from up to 1000 participants from clinical networks in the United States and Canada. Clinical information, demographics, and medical data relevant to cancer status are collected from all participants and their medical record at baseline (at study entry and time of baseline biospecimen collection), and subsequent visits per patient consent, for up to 1 year. The primary assessment is the establishment of a tumor registry with annotated clinical outcomes. Exploratory assessments include correlation of ex vivo functional testing results with clinical outcomes, as well as identification of potential biomarkers that correlate responses with genotype and/or phenotype. Inclusion Criteria: Provide written informed consent; Age ≥ 18 years, male or female, of any race; Suspected hematologic malignancy (any of the below), in need of starting an active anti-cancer therapy* Acute myelogenous leukemia (AML)a Multiple myeloma (MM) Myelodysplastic syndrome (MDS)a Lymphoma Acute lymphocytic leukemia (ALL) Chronic lymphocytic leukemia (CLL) Chronic myelogenous leukemia (CML) Myeloproliferative Neoplasm (MPN)a Other (upon review and approval by medical monitor) Intent to start anti-cancer therapy within 21 days of biospecimen collection; ≥ 7 days from last anti-cancer therapy; Any number of prior therapies Subject's cohort is currently opena *Supportive care agents including erythropoiesis-stimulating agents (ESAs) such as EPO, Procrit, Aranesp, etc; granulocyte colony stimulating factor (GCSF); hydroxyurea (Hydrea); and luspatercept (Reblozyl) are not considered anti-cancer therapy for this study aCohorts currently open and enrolling: AML, MDS, MPN Exclusion Criteria: Unwilling or unable to give consent; Disease is in remission; Subject's cohort is not open at the time of consent; Subject is restarting an ongoing treatment regimen after a dose interruption Statistical Methods: For the primary assessment, descriptive statistics will be used to summarize baseline patient characteristics, therapies, clinical outcomes, and collection of biospecimens. For exploratory analyses,hierarchical clustering using Euclidean distance metrics and Ward minimum variance will be used to identify patient clusters with distinctex vivodrug sensitivity patterns within a particular treatment cohort. The correlation between clinical response and drug sensitivity will be assessed using the area under the receiver-operator curve (AUROC) and bootstrapping to test for significance. A generalized estimation equation model will be used to identify associations between additional exploratory biomarkers, such as somatic mutations identified via NGS, andex vivosensitivity to various drug classes within specific treatment cohorts. 1Spinner M, et al. Ex Vivo Drug Screening Defines Novel Drug Sensitivity Patterns for Informing Personalized Therapy in Myeloid Neoplasms. Blood. 2020 June 23; 4(12):2768-2778. DOI: 10.1182/bloodadvances.2020001934. The ANSWer Study is currently enrolling at multiple sites across the US with plans to expand in the US and Canada: Figure Disclosures Wen: Notable Labs:Current Employment, Current equity holder in private company.Richardson:Notable Labs:Current Employment, Current equity holder in private company.Kita:Notable Labs:Current Employment, Current equity holder in private company.Tada:Notable Labs:Current Employment, Current equity holder in private company.

Identification of AML/MDS Drug Sensitization By In Vivo Chemotherapy Administration

Background: Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) are hematologic malignancies characterized by clonal myeloid expansion in the peripheral blood, bone marrow, and/or other tissues. During the past several years, the number of available FDA approved therapies for AML has dramatically increased, and multiple novel therapies for AML and MDS are in the pipeline. Not all patients will respond to these therapies, and early molecular markers of sensitivity vs resistance could facilitate selection of initial therapies or enable therapeutic pivots and personalization of treatment. Therefore, a sensitive method is required that will enable rapid identification of patients who are likely to benefit (or not benefit) from a therapy. In this study, we explore the feasibility of ex vivo drug screening to predict sensitivity and resistance to chemotherapy and to identify novel synergy between drug classes. Study Rationale: This study will test ex vivo sensitivity to chemotherapies before and during treatment to test the hypotheses that 1) ex vivo sensitivity prior to standard chemotherapy correlates with subsequent clinical outcomes; 2) increased ex vivo resistance following initial exposure to chemotherapy provides greater correlation with early treatment failure and clinical outcomes; 3) whether in vivo chemotherapy exposure leads to changes in ex vivo drug sensitivity and 4) whether patterns of ex vivo drug sensitivity can identify novel drug combinations and predict clinical outcomes. Study Design and Methods: This is a prospective, multi-arm, non-randomized single institution study enrolling subjects with AML and MDS who are anticipating treatment with one of four standard of care regimens (Figure 1). Primary endpoint: Determine whether Day 0 ex vivo drug sensitivity, as measured by a normalized blast count score, correlates with clinical responses for all cohorts. Key Secondary endpoints:Determine whether the drug sensitivity score obtained for Day 0 ex vivo treatments for all cohorts correlates with molecular responses.Determine whether the drug sensitivity score obtained for Day 0 ex vivo treatments for all cohorts correlates with survival.Determine whether an increase in the drug sensitivity score for Day 3 ex vivo sensitivity correlates with reduced clinical outcomes.Determine whether in vivo chemotherapy leads to increased ex vivo sensitivity to any class of drugs in more than 20% of patients treated on any study arm.Determine whether decitabine and azacitidine are associated with overlapping or unique profiles in drug sensitivity changes on Day 5.Determine whether ex vivo drug sensitivity correlates with the presence of clinically available mutations. Key Inclusion Criteria:Acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS)Peripheral blood blasts &amp;gt; 1%Peripheral white blood cell count &amp;gt; 1,000/μl.Age ≥ 18 yearsAnticipated treatment with any of the regimens in Figure 1ECOG performance status ≤ 3 Key Exclusion CriteriaPrior chemotherapy with hypomethylating agentsMust not have received any chemotherapy within 7 days of enrollment, and any acute treatment-related toxicities must have returned to baseline. Patients may have received hydrea, but must discontinue at the time of enrollment. Prior TKI therapy is allowed, but must be discontinued within 3 days of baseline blood collection.Currently receiving any other investigational agents. Statistical Methods: Clinical responses for AML will be assessed according to the 2017 ELN AML Recommendations. For MDS, clinical responses will be assessed for response according to the 2006 IWG criteria. Descriptive statistics will be used to summarize baseline patient characteristics, therapies, clinical outcomes, and collection of biospecimens. Hierarchical clustering using Euclidean distance metrics and Ward minimum variance will be used to identify patient clusters with distinct ex vivo drug sensitivity patterns within a particular treatment cohort. For the primary endpoint, the correlation between clinical response and drug sensitivity will be assessed using the area under the receiver-operator curve (AUROC) and bootstrapping to test for significance. A generalized estimation equation model will be used to identify associations between mutations and ex vivo sensitivity to various drug classes within specific treatment cohorts. Figure Disclosures Welch: Agios: Membership on an entity's Board of Directors or advisory committees; Janssen research: Research Funding; ArcherDx: Membership on an entity's Board of Directors or advisory committees; Notable labs: Research Funding. Richardson:Notable Labs: Current Employment, Current equity holder in private company. Kita:Notable Labs: Current Employment, Current equity holder in private company. Wen:Notable Labs: Current Employment, Current equity holder in private company. Tada:Notable Labs: Current Employment, Current equity holder in private company.

Molecular diagnosis, genetic diversity and drug sensitivity patterns of Mycobacterium tuberculosis strains isolated from tuberculous meningitis patients at a tertiary care hospital in South India.

Tuberculous meningitis (TBM) is the most severe form of Mycobacterium tuberculosis (Mtb) infection in humans and is a public health concern worldwide. We evaluated the performance of GeneXpert MTB/RIF (GeneXpert) for the diagnosis of TBM. In addition, genetic diversity and drug susceptibility profiling of Mtb strains isolated from TBM patients were also investigated. A total of 293 TBM suspected cerebrospinal fluid (CSF) samples were collected and subjected to GeneXpert and Mycobacterial Growth Indicator Tube (MGIT 960) culture, respectively. Sensitivity and specificity of GeneXpert was 72.7% and 98.5%, respectively by using MGIT 960 as a gold standard (GeneXpert (n = 20, 6.8%) vs MGIT 960 (n = 22, 7.5%)). All Mtb positive cultures were subjected to 24-locus Mycobacterial Interspersed Repetitive Unit Variable Number Tandem Repeat (MIRU-VNTR) typing, Line probe assay (LPA) and MGIT 960- Drug Susceptibility Testing (DST). The rpoB gene was amplified and sequenced for selected isolates. Among our TBM patients, East African Indian (EAI) lineage (n = 16, 72.7%) was most predominant followed by Beijing (n = 3, 13.6%), S-family (n = 2, 9.1%) and Delhi/CAS (n = 1, 4.5%). Three Mtb strains were found to be Isoniazid (INH) resistant by MGIT 960; however LPA revealed that two strains were INH resistant and one strain was multi drug resistant (MDR) (Resistant to Isoniazid and Rifampicin (RIF)). We identified rifampicin resistant isolate with the mutation D516F in rifampicin resistance-determining region (RRDR) and observed discordant results between LPA, GeneXpert and MGIT 960. In addition, GeneXpert showing false RIF resistance was identified (no mutation in RRDR). We conclude that GeneXpert is useful for the diagnostic confirmation of TBM; however a GeneXpert negative sample should be subjected to MGIT 960 culture or LPA to rule out TBM. EAI lineage was the most predominant among TBM patients in South India and associated with drug resistance. The discordance between GeneXpert, MGIT 960 and LPA with respect to rifampicin resistance has to be ruled out to avoid TB treatment failure or relapse.

Microbiology and Drug Sensitivity Pattern for Patients with Chronic Otitis Media in Aldiwanyia Teaching Hospital

Microbiology and Drug Sensitivity Pattern for Patients with Chronic Otitis Media in Aldiwanyia Teaching Hospital

Microbiological Profile and Drug Sensitivity Pattern in Persistently Discharging Ears: A Tertiary Level Hospital Based Retrospective Study

Introduction Antimicrobial resistance is an emerging issue resulting from the misuse of antibiotics in today’s world. As an effect of it, cases with persistent ear discharge not responding to the conventional oral antibiotics prescribed in ear pathologies are seen increasing in our day to-day practice. This study aims to review the microbiological growth and the pattern of their antibiotic sensitivity in this group of population.&#x0D; MethodsThis was a retrospective study which was conducted at the Department of ENT-HNS of Tribhuvan University Teaching Hospital. Record files of all cases who presented with persistently discharging ear for more than 2 weeks and not responding to oral antibiotics, between January 2017 to March 2020 were assessed. Cases of chronic otitis media (COM) squamous with persistent discharge were excluded as most of the times it is the disease process rather than type of organism which causes the persistence of ear discharge despite the use of antibiotics.&#x0D; ResultsCOM mucosal and cavity infection following modified radical mastoidectomy (MRM) were the commonest pathologies. Pseudomonas aeruginosa (PA) and Coagulase negative Staphylococcus (CoNS) were the commonest bacterial isolates. Pseudomonas aeruginosa showed a good sensitivity to antibiotics like Tazobactam and Piperacillin and resistance to conventionally used antibiotics like Ciprofloxacin and Levofloxacin. Similarly, CoNS had good sensitivity to antibiotics like Oxacillin and Levofloxacin and resistance to conventionally used antibiotics like Amoxicillin.&#x0D; ConclusionCOM mucosal and post MRM cavity infection are the commonest pathologies presenting with persistent ear discharge with PA and CoNS as the predominant isolates. Pseudomonas aeruginosa holds a good sensitivity to drugs like Tazobactam and Piperacillin; and CoNS to drugs like Oxacillin and Levofloxacin.

Microbiological Profile and Drug Sensitivity Pattern in Persistently Discharging Ears: A Tertiary Level Hospital Based Retrospective Study

Introduction: Antimicrobial resistance is an emerging issue resulting from the misuse of antibiotics in today’s world. As an effect of it, cases with persistent ear discharge not responding to the conventional oral antibiotics prescribed in ear pathologies are seen increasing in our day to-day practice. This study aims to review the microbiological growth and the pattern of their antibiotic sensitivity in this group of population. Methods: This was a retrospective study which was conducted at the Department of ENT-HNS of Tribhuvan University Teaching Hospital. Record files of all cases who presented with persistently discharging ear for more than 2 weeks and not responding to oral antibiotics, between January 2017 to March 2020 were assessed. Cases of chronic otitis media (COM) squamous with persistent discharge were excluded as most of the times it is the disease process rather than type of organism which causes the persistence of ear discharge despite the use of antibiotics. Results: COM mucosal and cavity infection following modified radical mastoidectomy (MRM) were the commonest pathologies. Pseudomonas aeruginosa (PA) and Coagulase negative Staphylococcus (CoNS) were the commonest bacterial isolates. Pseudomonas aeruginosa showed a good sensitivity to antibiotics like Tazobactam and Piperacillin and resistance to conventionally used antibiotics like Ciprofloxacin and Levofloxacin. Similarly, CoNS had good sensitivity to antibiotics like Oxacillin and Levofloxacin and resistance to conventionally used antibiotics like Amoxicillin. Conclusion: COM mucosal and post MRM cavity infection are the commonest pathologies presenting with persistent ear discharge with PA and CoNS as the predominant isolates. Pseudomonas aeruginosa holds a good sensitivity to drugs like Tazobactam and Piperacillin; and CoNS to drugs like Oxacillin and Levofloxacin.

Abstract 5399: The NSD2 p.E1099K mutation is enriched at relapse and confers drug resistance in a cell context dependent manner in pediatric acute lymphoblastic leukemia

Abstract Introduction: Outcomes for children with relapsed acute lymphoblastic leukemia (ALL) remain poor. Mutations in epigenetic modifiers are commonly found at relapse, including the activating p.E1099K (EK) mutation within the conserved SET domain of NSD2, which has been reported in 10% of patients at relapse. NSD2 has 3 isoforms, two of which (Types II and REIIBP) contain the SET domain. Our aim was to determine the role of NSD2 in driving relapse and further elucidate the prevalence of NSD2 EK in patient samples. Methods: Whole genome/exome sequencing was performed on diagnosis/relapse ALL pairs and data were aggregated for somatic SNVs/indels. NSD2 EK positive cases at relapse were subject to ultra-deep targeted re-sequencing to determine the presence of small subclones at diagnosis. To investigate the role of NSD2 and its isoforms in mediating relapse, short hairpin RNAs (shRNAs) were used to knockdown (KD) NSD2 in three NSD2 EK mutant cell lines with non-targeting (NT) shRNA used as controls. Cells were treated with chemotherapy commonly used in pediatric ALL and assessed for cytotoxicity by CellTiter- Glo®. To determine NSD2's impact on gene expression and the epigenetic landscape, RNAseq, ChIPseq, ATACseq, and Hi-C were performed using standard techniques. Results: Examination of paired ALL patient samples revealed enrichment of NSD2 EK clones at relapse. B-ALL cell lines heterozygous for NSD2 EK (RS4;11, RCH-ACV, SEM) revealed that KD led to decreased proliferation in all lines and decreased clonal growth in RCH-ACV relative to NT. Furthermore, increased sensitivity to various chemotherapeutic agents was observed in the KD lines compared to NT controls, but the pattern of drug sensitivity varied among lines implying cell context specific drug responses. Simultaneous knockdown of Type II and REIIBP had a greater impact than Type II alone, indicating both SET containing EK isoforms contribute to phenotypic changes. When comparing gene expression changes in NT vs KD, minimal overlap in differential genes was noted among the three cell lines (4.4% upregulated, 1.7% downregulated) indicating significant diversity in transcriptional reprogramming. ATACseq of the NT and KD for all three lines revealed intergenic regions as the most affected by NSD2 with RCH-ACV and RS4;11 NT lines having more open chromatin compared to their KD whereas SEM NT displayed marked peak loss compared to its KD. Less than 2% of differential intergenic regions were shared among the lines. Hi-C analysis demonstrated disparity in chromosome architecture among NSD2 EK lines as well. Shifts in intergenic regions was further supported by ChIPseq, which revealed increased H3K36me2 across intergenic regions in RS4;11 NT compared to KD. Lastly, we noted a strong correlation of increased gene expression with increased H3K36me2, H3K9ac, and H3K27ac at promoters and gene bodies. Conclusions: NSD2 EK plays a unique role in mediating clonal fitness through pleiotropic mechanisms that are dependent on the underlying cellular context. Citation Format: Joanna Pierro, Jason Saliba, Sonali Narang, Gunjan Sethia, Shella Saint Fleur-Lominy, Ashfiyah Chowdhury, Takaya Moriyama, Kjeld Schmiegelow, Jun J. Yang, Mignon L. Loh, Patrick A. Brown, Jinghui Zhang, Xiaotu Ma, Aristotelis Tsirigos, Nikki A. Evensen, William L. Carroll. The NSD2 p.E1099K mutation is enriched at relapse and confers drug resistance in a cell context dependent manner in pediatric acute lymphoblastic leukemia [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5399.

The NSD2 p.E1099K Mutation Is Enriched at Relapse and Confers Drug Resistance in a Cell Context–Dependent Manner in Pediatric Acute Lymphoblastic Leukemia

The NSD2 p.E1099K (EK) mutation is observed in 10% of acute lymphoblastic leukemia (ALL) samples with enrichment at relapse indicating a role in clonal evolution and drug resistance. To discover mechanisms that mediate clonal expansion, we engineered B-precursor ALL (B-ALL) cell lines (Reh, 697) to overexpress wildtype (WT) and EK NSD2, but observed no differences in proliferation, clonal growth, or chemosensitivity. To address whether NSD2 EK acts collaboratively with other pathways, we used short hairpin RNAs to knockdown expression of NSD2 in B-ALL cell lines heterozygous for NSD2 EK (RS4;11, RCH-ACV, SEM). Knockdown resulted in decreased proliferation in all lines, decreased clonal growth in RCH-ACV, and increased sensitivity to cytotoxic chemotherapeutic agents, although the pattern of drug sensitivity varied among cell lines implying that the oncogenic properties of NSD2 mutations are likely cell context specific and rely on cooperative pathways. Knockdown of both Type II and REIIBP EK isoforms had a greater impact than knockdown of Type II alone, suggesting that both SET containing EK isoforms contribute to phenotypic changes driving relapse. Furthermore, in vivo models using both cell lines and patient samples revealed dramatically enhanced proliferation of NSD2 EK compared with WT and reduced sensitivity to 6-mercaptopurine in the relapse sample relative to diagnosis. Finally, EK-mediated changes in chromatin state and transcriptional output differed dramatically among cell lines further supporting a cell context-specific role of NSD2 EK. These results demonstrate a unique role of NSD2 EK in mediating clonal fitness through pleiotropic mechanisms dependent on the genetic and epigenetic landscape. IMPLICATIONS: NSD2 EK mutation leads to drug resistance and a clonal advantage in childhood B-ALL.

Clinicomycological study of vulvovaginal candidiasis.

Background:Vaginal candidiasis is one of the most common vaginal infections in women of reproductive age group caused by Candida species of fungi, a normal inhabitant of vagina.Aims:The aim is to study the culture characteristics, species prevalence, and drug sensitivity of vulvovaginal candidiasis (VVC) among females with genital pruritus and discharge per vaginum who are proved to have Candida infection by a vaginal smear study.Materials and Methods:A prospective study was done on female patients aged 18 years attending the Sexually Transmitted Diseases Clinic of the Department of Dermato-Venereo-Leprology (DVL), Tirunelveli Medical College, with complaints of genital pruritus and vaginal discharge over a period of 1½ years from 2013 to 2015. After clinical examination, vaginal discharge was smeared for wet mount, potassium hydroxide mount, and Gram stain. Those with pseudohyphae were chosen for culture, speciation, and drug sensitivity.Results:The most common age group affected was 18–35 years. The most common predisposing factor was HIV infection-induced immunosuppression (48.7%), followed by antibiotic usage and diabetes mellitus. Clinical presentation of VVC was similar in HIV-positive and HIV-negative patients. Recurrent VVC makes up 12% of total cases with most common species being Candida albicans whereas Candida glabrata among the non-C. albicans. Drug sensitivity pattern of C. albicans showed the highest sensitivity to nystatin 85.7%, followed by triazoles (75%–85%) with ketoconazole being more resistant (40%–60%), and was similar in C. albicans and non-C. albicans.Limitations:Exclusion of unmarried and pregnant women and lack of follow-up were limitations in our study.Conclusions:According to our study, elimination of predisposing factors, speciation of fungus, and treatment based on drug sensitivity pattern will reduce the incidence of VVC.

Diagnosis and Management of Osteoarticular Tuberculosis: A Drastic Change in Mind Set Needed-It is Not Enough to Simply Diagnose TB.

In the era of increasing drug resistance in pulmonary tuberculosis (TB), it is prudent to assess causes of poor response to anti tubercular therapy (ATT) and drug sensitivity pattern (DSP) in osteoarticular TB. As a part of Bombay Orthopaedic society's research project, members were asked to refer non responders to ATT to our institute. Cases were enrolled from October 2010 to March 2014. Deep tissue samples were obtained in all but five cases and subjected to a battery of tests including histopathology (HPE) and TB culture and sensitivity. The DSP was compared with the study performed by the principle author from 2004 to 2007 and published in 2009. 39 male and 50 female patients with a mean age of 24.85years (2-66) were included and classified in four groups after results. (1) Culture and HPE positive-36. 24 had MDR and three XDR TB. Primary resistance to even second line drugs and deterioration of DSP since last study was noted, (2) culture negative and HPE positive-21. The cause of poor response was surgical in more than half cases, (3) non representative samples or lost to follow-up-15, (4) TB mimics-16. There is increasing incidence of primary resistance to second line drugs, primary resistance in children and worsening of resistance patterns as compared to older studies. ATT initiation is a fateful decision and every attempt should be made to rule out TB mimics and establish DSP before initiation.

Urinary pathogenic bacterial profile, antibiogram of isolates and associated risk factors among diabetic patients in Hawassa town, southern Ethiopia: a cross-sectional study

Urinary tract infection (UTI) is the commonest bacterial infectious disease in community practice with a high rate of morbidity and financial cost. It has been estimated that 150 million people were infected with UTI per annum worldwide which costing global economy more than 6 billion US dollar. In humans, urinary tract is the second commonest site after the respiratory tract, for bacterial infection. Two hundreds forty seven diabetic patients were investigated for UTI using 5 to 10ml midstream urine sample. A loop full urine sample was inoculated on cysteine lactose electrolyte deficient (CLED) agar, MacConkey agar and Blood agar plates. Antimicrobial susceptibility test was done using Clinical and Laboratory Standards Institute (CLSI) for all patients. Age, sex, resident, marital status and other factors were used as exposure factor of the cross sectional study. The aim of this study was to assess etiology, risk factors and drug sensitivity pattern of uropathogenic bacteria isolated from diabetic patients. The overall prevalence of significant bacteriuria was 26(10.5%). Significant bacteriuria was significantly associated with age and body mass index. The predominant bacteria isolate was E. coli 12(46.2%) followed by Coagulase negative staphylococcus 7(26.9%).Gram negative bacteria showed high rate of sensitivity (94.1%) to Nitrofurantoin and Norfloxacine. Gram positive bacteria showed 100% sensitive for Amoxacillin-Clavunic acid. Multidrug resistance to two or more drug was observed in 19(73.1%) of bacteria isolates. The overall prevalence of significant UTI in diabetic patients was 10.5%. The most frequently observed organisms were E. coli, CONs, K. pneumoniae, K. oxytoca and S. aureus. Sex, age, BMI, occupational status such as house wife was statistically significant. Gram negative bacteria isolates were the most common antibiotic resistant bacteria isolates from UTI patients.

Responsible antimicrobial use in critically ill adult horses

SummaryDue to increasing antimicrobial resistance, pressure on veterinarians is mounting to adhere to responsible use of antimicrobial drugs. Antimicrobials are frequently included in the treatment of systemically ill horses due to the strong likelihood of an infection and the innate difficulties in differentiating systemic inflammation secondary to noninfectious from infectious causes. In light of increasing antimicrobial drug resistance and the potential negative impact of antimicrobials on equine patients, every attempt should be made to identify noninfectious disease, choose first‐line antimicrobials and discontinue treatment as soon as possible. In most cases, a short duration of antimicrobial therapy ranging from a single dose (e.g. preoperatively) to 24–72 h might be sufficient with long‐term treatment being rarely required. This article aims to provide practical guidelines for antimicrobial drug usage in critically ill adult horses by describing ancillary diagnostic aids that can help establishing whether or not an infection is present, discussing commonly encountered pathogens and their typical antimicrobial drug sensitivity patterns, and providing some guidance how to safely shorten the duration of antimicrobial therapy.

Ex vivo drug screening defines novel drug sensitivity patterns for informing personalized therapy in myeloid neoplasms

AbstractPrecision medicine approaches such as ex vivo drug sensitivity screening (DSS) are appealing to inform rational drug selection in myelodysplastic syndromes (MDSs) and acute myeloid leukemia, given their marked biologic heterogeneity. We evaluated a novel, fully automated ex vivo DSS platform that uses high-throughput flow cytometry in 54 patients with newly diagnosed or treatment-refractory myeloid neoplasms to evaluate sensitivity (blast cytotoxicity and differentiation) to 74 US Food and Drug Administration–approved or investigational drugs and 36 drug combinations. After piloting the platform in 33 patients, we conducted a prospective feasibility study enrolling 21 patients refractory to hypomethylating agents (HMAs) to determine whether this assay could be performed within a clinically actionable time frame and could accurately predict clinical responses in vivo. When assayed for cytotoxicity, ex vivo drug sensitivity patterns were heterogeneous, but they defined distinct patient clusters with differential sensitivity to HMAs, anthracyclines, histone deacetylase inhibitors, and kinase inhibitors (P < .001 among clusters) and demonstrated synergy between HMAs and venetoclax (P < .01 for combinations vs single agents). In our feasibility study, ex vivo DSS results were available at a median of 15 days after bone marrow biopsy, and they informed personalized therapy, which frequently included venetoclax combinations, kinase inhibitors, differentiative agents, and androgens. In 21 patients with available ex vivo and in vivo clinical response data, the DSS platform had a positive predictive value of 0.92, negative predictive value of 0.82, and overall accuracy of 0.85. These data demonstrate the utility of this approach for identifying potentially useful and often novel therapeutic drugs for patients with myeloid neoplasms refractory to standard therapies.

Neonatal sepsis: Bacterial aetiological agents and drug sensitivity pattern in a tertiary hospital in North-Central Nigeria

The Journal is the primary organ of Continuing Paediatric Medical Education in Sri Lanka. The journal also has a website. Free full text access is available for all readers.The Sri Lanka Journal of Child Health is now indexed in SciVerse Scopus (Source Record ID 19900193609), Index Medicus for South-East Asia Region (IMSEAR), CABI (Centre for Agriculture and Bioscience International Global Health Database), DOAJ and is available in Google, as well as Google Scholar.The policies of the journal are modelled on the Committee on Publication Ethics (COPE) Guidelines on Principles of Transparency and Best Practice in Scholarly Publishing. Sri Lanka Journal of Child Health is recognised by the International Committee of Medical Journal Editors (ICMJE) as a publication following the ICMJE Recommendations.

Image-based ex vivo drug screen to assess targeted therapies in recurrent thymoma

ObjectivesThymoma is a rare malignancy derived from the thymic epithelial cells. No standard salvage treatments are available for recurrent thymoma and due to the low number of cases, alternative treatment regimens have been assessed only in small case series with varying success. The aim of this study was to use an image-based ex vivo drug screening strategy to assess efficacy of a large panel of anti-cancer agents for thymoma using patient derived tumor cells. Materials and MethodsVital tumor and tumor associated cells were used to assess the efficacy of 147 anti-cancer drugs including approved and experimental agents. Drug efficacy was analyzed at single cell resolution using image-based high content drug screening to assess tumor cell specific responses. Molecular profiling and histopathology was used to confirm the drug targets identified by the screen. ResultsThe ex vivo drug screen identified selective sensitivity of the cancerous epithelial thymoma cells to EGFR-, HDAC- and mTOR-inhibition. Histopathology confirmed high protein level expression of EGFR in the patient’s tumor. Patient was initiated treatment with Cetuximab resulting in stable disease after relapse on five different chemotherapy regimens. ConclusionThe results show that the image-based ex vivo therapy efficacy screening strategy can be used to identify patient and tumor relevant drug sensitivity patterns in thymoma. The results also warrant continued research on EGFR as a biomarker and therapy target in recurrent thymomas.