Endemic Indian clones of Klebsiella pneumoniae‑harbouring New Delhi metallo‑beta‑lactamase‑1 on a hybrid plasmid replicon type: A case of changing New Delhi metallo‑beta‑lactamase plasmid landscapes in India.

Purpose: blaNDM genes are MBL genes that confer resistance to carbapenems. Globally, they are associated with diverse clones and plasmids. In this study, we characterised three isolates of Klebsiella pneumoniae‑harbouring blaNDM1 from patients undergoing chronic haemodialysis and renal transplantation. Materials and Methods: 3 blaNDM1‑producing K. pneumoniae were isolated from end‑stage renal disease patients undergoing haemodialysis and renal transplantation from a nephrology unit. All the three isolates were screened for clinically relevant resistant genes. Plasmid replicon content was analysed by polymerase chain reaction based replicon typing. Conjugation assays were done using azide‑resistant Escherichia coli J53 as the recipient strain. Multilocus sequence typing and variable number tandem repeat typing were done to find the clonality. Replicon sequence based typing was attempted to find the diversity of replicon‑associated sequences in IncHI3 plasmids. Results: All the 3 blaNDM positive isolates possessed the New Delhi metallo‑beta‑lactamase‑1 (NDM‑1) allele with an IncHI3 plasmid which was not transferable in one isolate. The isolates were found to be sequence type 14 (ST14; 2 nos) and ST38 both of which were previously reported to be the NDM‑producing K. pneumoniae STs prevalent in India. Replicon sequence analysis revealed limited sequence diversity within the repHI3 and repFIB locus. Conclusion: To the best of our knowledge, this is the first report of IncHI3, a newly assigned enterobacterial plasmid incompatibility group from India. This could either be a case of importation or a widely circulating NDM plasmid type in India.

Development of polyvinyl chloride biofilms for succession of selected marine bacterial populations.

Present investigation was made to bring out the pattern of biofilm formation by heterotrophic bacteria on nontoxic material, polyvinyl chloride (PVC) sheet fitted wooden rack that was immersed in seawater and the study was conducted in Tuticorin coast. Samplings were made over a period of 7 days with the following time period intervals: 30 min, 1, 2, 4, 24, 48, 72, 96, 120 and 144 hr. Bacterial enumeration was made by spread plate method on nutrient agar medium and characterization of bacterial isolates up to generic level was done. Gram-negative bacteria like Pseudomonas sp., Enterobacter sp., Aeromonas sp., Cytophaga sp. and Flavobacterium sp. were found to be the pioneer in colonizing the surface within 30 min and seven genera were represented in the biofilm. Among them two genera were found belonging to Gram-positive groups which included Micrococcus and Bacillus sp. The early stage biofilm i.e. up to 24th hr was wholly constituted by Gram-negative groups. However, the population density of Pseudomonas sp. was found to be higher (315 CFU) when compared to other Gram-negative forms. Occurrence of Gram-positive group was noted only at 48th hr old biofilm (28 to 150 CFU). The period between 48 and 96th hr was the transition where both the Gramnegative and Gram-positive groups co- existed. After 96th hr, the biofilm was found constituted only by Grampositive groups. The isolates of early stage biofilm were found to produce allelopathic substance like bacteriocin.

Prospects for elimination of leprosy in India by 2000 AD.

Data regarding the trends of new-case detection rates of leprosy for India as a whole, for the State of Andhra Pradesh, and for Srikakulam district in Andhra Pradesh were generated and projected up to 2000 AD. The prevalence rate by 2000 AD was worked out based on these new -case detection rates. The projections show that at the current slowly declining trend of new-case detection, with 20% MB cases among the newly detected cases and the current mean duration of treatment, the elimination goal of leprosy by 2000 AD, could possibly be achieved at Srikakulam district level only, where the MDT project has been under implementation for over ten years, but not at the State or country levels. The achievement of elimination goal should be possible in other geographic units also if the duration of disease could be shortened to one month or less, for both paucibacillary and multibacillary types of leprosy.

Deformity incidence in leprosy patients treated with multidrug therapy.

The records of 2,285 (2,007 paucibacillary (PB) and 278 multibacillary (MB)) cases of leprosy which were declared as released from treatment (RFT) after multidrug therapy (MDT) and under surveillance as per the National Leprosy Eradication Programme (NLEP) guidelines in the rural field practice area of Central Leprosy Teaching & Research Institute (CLTRI), Chengalpattu, between September 1986 and September 1993 were analyzed for collecting data on the incidence of deformity. Of the 2,285 cases 2,053 (1,947 PB and 106 MB) did not have deformity at the commencement of treatment. Three MB cases and one PB case out of the 2,053 developed deformity (all grade II) during the course of treatment. No patient developed deformity during surveillance. Thus the deformity incidence in the population of patients was 0.681 per 1000 person-years of observation. Age, sex, type of disease, prior dapsone monotherapy and nerve involvement at the commencement of treatment appear to influence the deformity incidence. The risk of development of deformity in patients treated with MDT appear to be very low and analysis of larger data sets is suggested to corroborate the above findings as the information would be useful for planning prevention and management of deformity services.