Transmission of carbapenem-resistant pathogens in New York City hospitals: progress and frustration.

OBJECTIVES: Carbapenem-resistant Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa are endemic in many medical centres. Because therapeutic options are limited, understanding the epidemiology and controlling the spread of these pathogens are of paramount importance. METHODS: Isolates of K. pneumoniae, A. baumannii and P. aeruginosa were collected from 14 hospitals in New York City over a 3 month period in 2009, and analysed for the presence of genes encoding important carbapenemases. Comparisons were made with a similar study conducted in 2006. Demographic and infection control-related information from hospitals was collected. RESULTS: Overall, 29% of K. pneumoniae possessed the carbapenemase KPC, significantly improved from the 38% observed in 2006 (P < 0.001). However, carbapenem resistance worsened in A. baumannii (mostly due to the emergence of strains with OXA-type carbapenemases) and P. aeruginosa. The decline in KPC-possessing K. pneumoniae was not uniformly observed in all of the hospitals. In a subset analysis of nine hospitals, those with a decreasing prevalence of bla(KPC) had shorter average lengths of stay. CONCLUSIONS: Measurable improvement has occurred in reducing the spread of KPC-possessing K. pneumoniae, and reducing the average length of stay may augment infection control efforts. However, the problem of carbapenem-resistant A. baumannii and P. aeruginosa lingers. New approaches, including respiratory isolation and environmental cleaning, need to be examined to control the spread of A. baumannii and P. aeruginosa.

Activity of polymyxin B and the novel polymyxin analogue CB-182,804 against contemporary Gram-negative pathogens in New York City.

Multidrug-resistant Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa have become common in many regions, often requiring therapy with colistin or polymyxin B. An increase in resistance to these agents would render many infections untreatable. We tested the activity of polymyxin B and the novel polymyxin analogue CB-182,804 against over 5,000 recent Gram-negative clinical isolates from New York City, a region with a high prevalence of multiresistant strains. Over 96% of Escherichia coli, K. pneumoniae, A. baumannii, and P. aeruginosa were susceptible to polymyxin B; only 76% of Enterobacter spp. was susceptible. The MICs of CB-182,804 were generally two-fold higher than polymyxin B and cross-resistance was observed. The addition of rifampin resulted in synergistic inhibition and bactericidal activity in time kill studies, and restored activity against all polymyxin-resistant strains. The synergistic effect of the combination with rifampin was most pronounced against A. baumannii strains, and was slightly greater with CB-182,804 than with polymyxin B against K. pneumoniae and Enterobacter spp. Despite considerable usage of polymyxin B and colistin in this region, polymyxin B retains excellent activity against most Gram-negative isolates. CB-182,804 shows similar activity, particularly when combined with rifampin. The clinical utility of CB-182,804 remains to be determined.

Staphylococcus lugdunensis: the coagulase-negative staphylococcus you don't want to ignore.

Staphylococcus lugdunensis is a virulent coagulase-negative staphylococcus (CoNS) that behaves like Staphylococcus aureus. Toxic shock syndrome, osteomyelitis, septic arthritis and postoperative endopthalmitis have been observed. Endocarditis complicated by heart failure, periannular abscess formation and embolic phenomenon have brought particular attention to this CoNS. Mortality rates for endocarditis appear higher when compared with other CoNS. Owing to the laboratory methods used, identification may be misleading. ß-lactam antimicrobials are recommended pending sensitivities. Evaluation for endocarditis should be pursued in bacteremic patients due to its pathogenic potential.

Principles and practice of disaster relief: lessons from Haiti.

Disaster relief is an interdisciplinary field dealing with the organizational processes that help prepare for and carry out all emergency functions necessary to prevent, prepare for, respond to, and recover from emergencies and disasters caused by all hazards, whether natural, technological, or human-made. Although it is an important function of local and national governing in the developed countries, it is often wanting in resource-poor, developing countries where, increasingly, catastrophic disasters tend to occur and have the greatest adverse consequences. The devastating January 12, 2010, Haiti earthquake is a case study of the impact of an extreme cataclysm in one of the poorest and most unprepared settings imaginable. As such, it offers useful lessons that are applicable elsewhere in the developing world. Emergency preparedness includes 4 phases: mitigation or prevention, preparedness, response, and recovery. Periods of normalcy are the best times to develop disaster preparedness plans. In resource-poor countries, where dealing with the expenses of daily living is already a burden, such planning is often neglected; and, when disasters strike, it is often with great delay that the assistance from international community can be deployed. In this increasingly interconnected world, the Haiti earthquake and the important international response to it make a strong case for a more proactive intervention of the international community in all phases of emergency management in developing countries, including in mitigation and preparedness, and not just in response and recovery. Predisaster planning can maximize the results of the international assistance and decrease the human and material tolls of inevitable disasters. There should be a minimum standard of preparedness that every country has to maintain and the international assistance to achieve that. International academic medical centers interested in global health could strengthen their programs by prospectively including in them contingency planning for international relief operations. Healthcare professionals of these institutions who travel to disaster zones should rigorously prepare themselves and make provisions for collecting and reporting data, which will enrich the knowledge of this growing activity.

Antimicrobial activity of a novel aminoglycoside, ACHN-490, against Acinetobacter baumannii and Pseudomonas aeruginosa from New York City.

OBJECTIVES: Multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa have become a global problem, often leaving the polymyxins as therapeutic agents of last resort. ACHN-490, a next-generation aminoglycoside with activity against a broad range of Gram-positive and Gram-negative pathogens, was examined against clinical isolates of A. baumannii and P. aeruginosa. METHODS: The activity of aminoglycosides and ACHN-490 was determined against a contemporary collection of A. baumannii and P. aeruginosa. Selected aminoglycoside-resistant isolates were screened for the presence of genes encoding common aminoglycoside-modifying enzymes and methylases. RESULTS: Resistance to the traditional aminoglycosides was common in the collection of A. baumannii. ACHN-490 possessed superior activity against these isolates, with an MIC(50) value of 8 mg/L. In P. aeruginosa, the activity of ACHN-490 was similar to that of amikacin (MIC(50) value of 8 mg/L for both agents). For both A. baumannii and P. aeruginosa, the MICs of ACHN-490 did not correlate with the presence of commonly encountered aminoglycoside-modifying enzymes. CONCLUSIONS: For A. baumannii, the MICs of ACHN-490 were lower than those of traditional aminoglycosides. For P. aeruginosa, the activity of ACHN-490 was similar to that of amikacin.

Susceptibility profiles, molecular epidemiology, and detection of KPC-producing Escherichia coli isolates from the New York City vicinity.

The detection of Enterobacteriaceae carrying the carbapenemase KPC has been problematic. Thirty isolates of KPC-possessing Escherichia coli were gathered from hospitals in New York City and Connecticut. The imipenem, meropenem, doripenem, and ertapenem MIC50 values were 4, 2, 1, and 4 µg/ml, respectively. Over half of the isolates belonged to a single ribotype. Using an ertapenem breakpoint of 0.25 µg/ml would efficiently detect these isolates.

Activity of a novel aminoglycoside, ACHN-490, against clinical isolates of Escherichia coli and Klebsiella pneumoniae from New York City.

OBJECTIVES: Reports of Enterobacteriaceae resistant to all commonly used antimicrobial agents, including ß-lactams, fluoroquinolones and aminoglycosides, are increasing in hospitals worldwide. The activity of ACHN-490, a next-generation aminoglycoside, was examined against clinical isolates of Escherichia coli and Klebsiella pneumoniae from hospitals in New York City, an area where multidrug-resistant organisms are endemic. METHODS: Unique patient isolates of E. coli and K. pneumoniae were gathered from 16 hospitals located in New York City in 2009 and underwent susceptibility testing to aminoglycosides and ACHN-490. Subsets of isolates were characterized by PCR for the presence of genes encoding aminoglycoside-modifying enzymes, ribosomal methylases and KPC-type carbapenemases. RESULTS: Although most isolates of E. coli were susceptible to the aminoglycosides, the MIC(90) values of gentamicin, tobramycin and amikacin were 32, 8 and 4 mg/L, respectively. The MIC(90) of ACHN-490 was 1 mg/L. Multidrug resistance, including resistance to aminoglycosides and the presence of bla(KPC), was much more common in isolates of K. pneumoniae. However, the MIC(90) of ACHN-490 for K. pneumoniae was also 1 mg/L. The MICs of ACHN-490 did not correlate with the presence of commonly recovered aminoglycoside-modifying enzymes. Bactericidal activity was evident in most isolates at concentrations 4× the MIC. CONCLUSIONS: The novel aminoglycoside ACHN-490 retains activity against most isolates of E. coli and K. pneumoniae, including multidrug-resistant strains. Additional studies examining the roles of efflux systems and outer membrane permeability alterations are recommended in isolates with reduced susceptibility to this agent.

First case of cutanous leishmaniasis in Nepalese patient.

Visceral Leishmaniasis (VL) is a serious disease caused by Leishmania donovani (LD) complex and prevalent in the temperate and tropical zones of the earth. VL, endemic in the southern plains of the 14 districts in the Terai region of Nepal, is considered a major public health problem. Cutanous leishmaniasis (CL) is prevalent mainly in the tropics and subtropics, affects nearly 1.5 million people worldwide. No reported cases of CL have been identified in Nepal until now. We report the first case of CL in a Nepalese patient.