ABSTRACT
Objective: To assess plasma Epstein-Barr virus (EBV) DNA as a biomarker of tumour burden at diagnosis and during therapy in children with Hodgkin lymphoma. Design: Case-control study, with prospective follow-up of the Hodgkin lymphoma cohort (2007-2012). Setting: Pediatric Hematology Oncology unit of a tertiary care hospital in Delhi. Patients: Thirty children with Hodgkin lymphoma and 70 sex and age-matched controls (benign lymphadenopathy 19, non-lymphoid malignancy 29, Burkitt lymphoma 5, healthy children 17). Intervention: Positive EBV-staining on immunohistochemistry was defined as EBV-associated Hodgkin lymphoma. Plasma EBV real-time quantitative polymerase chain reaction (PCR) was tested at presentation, after first and last chemotherapy cycles, and on follow-up. Main outcome measures: Plasma EBV quantitative PCR was compared between cases and controls. Its kinetics was assessed during and after chemotherapy. Results: EBV quantitative PCR was positive in 19 (63%) Hodgkin lymphoma cases (range 500–430,000 copies/mL), with 87.5% accuracy (kappa=0.69) as compared with EBVimmunohistochemistry. Sensitivity and specificity of the quantitative PCR were 87.5% and 81.8%, respectively. Only boys showed positive EBV immunohistochemistry and/or quantitative- PCR positivity. All controls were quantitative-PCR negative. All quantitative-PCR positive cases with follow-up blood sample showed EBV clearance after the first cycle. A quantitative-PCR negative case in long-term remission became positive at relapse. EBV status did not influence survival. Conclusion: Plasma EBV-DNA, detectable in EBV-associated Hodgkin lymphoma, becomes undetectable early after initiating therapy. It can be used as a biomarker of treatment response in EBV-associated Hodgkin lymphoma.
ABSTRACT
Background & objectives: Extensive use of antibiotics has added to the escalation of antibiotic resistance. This study was undertaken to evaluate the association, if any between antibiotic use and resistance in a hospital setting, and also detect the predominant mechanism of antibiotic resistance in Escherichia coli and Klebsiella pneumoniae over a period of 10 years. Methods: In a retrospective study of 10 years, a total of 77,618 blood culture samples from 2000 to 2009 from indoor patients were screened and those yielding E. coli and K. pneumoniae were included in the study. Antibiotic susceptibility records as well as the percentage of ESBL producers were noted. A total of 423 isolates of 2009 were also screened for AmpC and carbapenemase production. Antibiotic consumption data of 10 years were analysed. Results: ESBL producing E. coli increased from 40 per cent in 2002 to 61 per cent in 2009, similarly there was a significant (P<0.05) rise in resistance to cefotaxime (75 to 97%), piperacillin-tazobactum (55- 84%) and carbapenem (2.4-52%) in K. pneumoniae. A significant (P<0.05) association was observed between resistance and consumption of carbapenem and piperacillin and tazobactum consumption in K. pneumonia. Interpretation & conclusions: Our study demonstrated a rise in consumption and resistance to broad spectrum antimicrobial agents and also established an association between consumption and resistance to these antibiotics. Over a period of 10 years, the emergence of pan-resistance in K. pneumoniae could be due to the production of carbapenemases whereas ESBL production was the common mechanism of resistance in E. coli. This study warrants a directed effort towards continued surveillance and antibiotic stewardship to minimize selection pressure and spread.