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Objectives: Virulent strains of Pseudomonas aeruginosa exhibit multidrug resistance by intrinsic and extrinsic mechanisms which are regulated by quorum sensing signalling systems. This includes the production of auto-inducers and their transcriptional activators to activate various virulence factors resulting in host infections. The present study is thus aimed to detect the virulence factor production, quorum sensing activity, and susceptibility pattern of P. aeruginosa to antibiotics from clinical specimens. Materials and Methods: A total of 122 isolates of P. aeruginosa were phenotypically characterized by standard protocols and were categorized into MDR and non-MDR based on the antibiotic susceptibility profiles. Pyocyanin, alkaline protease and elastase production were assessed by qualitative and quantitative methods. Crystal violet assay was carried out for the quantification of biofilms. The genetic determinants of virulence were detected by PCR. Results: Out of the 122 isolates, 80.3% of isolates were MDR and the production of virulence factors was in positive correlation with the presence of genetic determinants and 19.6% were non-MDR, but still showed the production of virulence factors, as confirmed by both phenotypic and genotypic methods. Few carbapenem-resistant strains were detected which did not show the production of virulence factors by both methods. Conclusion: The study concludes, though the strains were non-MDR, they were still capable of producing the virulence factors which may be responsible for the dissemination and chronicity of the infection caused by P. aeruginosa.
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INTRODUCTION: The classification of acute leukemias has revolutionized over the years. Immunophenotyping of acute leukemia has gained popularity because of its influence on treatment and prognosis of the disease. The various antigens expressed by the leukemic cells can be assessed by flowcytometry (FCA) and can be used in rendering specific treatment and predicting the outcome of the different types of acute leukemia. AIMS: The main aim of this study was to compare the morphologic and cytochemical diagnoses with flowcytometric diagnoses in acute leukemia and to analyze the usefulness of FCA over morphology. RESULTS: In this study we analyzed 50 cases of acute leukemia and found concordance rate as high as 86% between morphologic/cytochemical diagnosis and flowcytometric diagnosis. Of these, complete concordance was seen in 58% of the cases and partial concordance was seen in 22% of the cases. Non-concordance was seen in only 4% of our cases. In remaining 16% of our cases FCA helped in sub classifying the acute leukemia where morphology and cytochemistry had failed to do so. CD19 and 20 were found to be consistent B-cell markers and CD3 was a very specific marker for T-cell leukemia. CD13 and 33 were important myeloid markers and were aided by other secondary panel of markers like CD14, CD117 and CD41. CONCLUSION: FCA not only helps in confirming morphologic diagnosis in acute leukemia but also helps in assigning specific lineage to the blasts, particularly in acute lymphoid leukemia. Immunophenotyping is of utmost importance in classifying acute leukemia as it greatly influences the treatment and the prognosis.
