Can traditional infection control strategies limit carbapenemase-producing Klebsiella pneumoniae (CPKP) hospital acquired infections?

Background: Carbapenemase production was first described in Klebsiella pneumoniae in 2001. Since then, reports on CPKP outbreaks in New York, Israel, Greece and China etc have been described. To date, traditional infection control (IC) strategies have not been able to abort outbreaks with the microorganism becoming endemic.

Objective: To describe an outbreak of CPKP in a Colombian third level hospital.

Methods: This is a descriptive study. Hospital Pablo Tobon Uribe is a 288-bed hospital with adult and pediatric ICUs and solid organ and bone marrow transplantation programs. Three cases of infection by CPKP were identified with the index case coming from Israel for a liver transplant. An outbreak alarm in the adult ICU was declared. Environmental cultures in the wards were then obtained. All patients infected and colonized were identified. Infection control measures were escalated in a progressive manner, as follows: gowns, gloves and dispensers for alcohol-based hand-rub in each room, contact precautions, single room and daily chlorhexidine bath for affected patients, geographic cohorting of patients in ICUs, staff cohorting as much as possible, limiting admissions and flagging of affected patients to assure preemptive isolation on readmission. Periodic surveillance cultures (sputum, perirectal and wound if applicable) of all ICUs patients were obtained and processed in a standard fashion. Another cohortization area, apart from the ICUs was designated for all affected patients. Cleaning procedures were standardized and an intensive hand hygiene campaign was made compulsory. The use of long sleeved-white coats and jewelry was forbidden to all healthcare workers. The study was approved by IRB/EC of the Hospital.

Results: From January 2008 to October 2009, we identified 157 patients with CPKP, 51 of whom were infected and 106 were colonized; 94 were men. Mean age was 48.5 years (SD 24.6); 55 patients were in the adult- and 18 in the pediatric-ICUs. Additionally, another 84 cases occurred in regular wards.

From 108 environmental cultures taken 4 grew CPKP which corresponded to 2 computer keyboards, 1BP cuff and 1 mothers' feeding cushion. A large number (15.998) surveillance cultures were obtained with 0.66% giving positive results. Hand hygiene compliance increased to 88%. The Figure shows the number of cases per 1000 patients/ days.

Conclusions: This outbreak has been difficult to restrain despite efforts aimed to find a common source, escalation of infection control procedures and adherence to infection control strategies. As K. pneumoniae is part of the normal gastrointestinal flora and patients remain colonized for prolonged periods, the adequate control of this problematic organism by the traditional infection control methods is difficult. Our findings highlight the need to develop new strategies for prevention and infection control in hospital wards.