MRSA / S.aureus are not often found to be the etiology of lung infection except in hospitalized patients who reside in the Intensive Care Units. Often the victim requires ventilation, meaning the bacteria can bypass the humoral and physical defenses of the nose and throat. Endotracheal intubation can also be a method of MRSA pneumonia, often fatal in the debilitated patient. Hypothesis

Given the prevalence of MRSA within the hospital population, both patient and staff, and given the rate of MRSA infection within the general population, it is my hypothesis that it is more likely for patients to be contaminated with MRSA in radiological procedures which require the use of multi-patient equipment that goes through rudimentary cleaning, rather than radiographic procedures using multi-use equipment which goes through rigorous cleaning between each patient.

Literature Review

In essence, while a multitude of data and peer reviewed journal articles exist on MRSA, from colonization to hospital eradication programs, it was very difficult to find and studies in which the details were specific to the radiology department. Chief topics seem to currently surround the likelihood that MRSA is developing into a community rather than hospital based (or nosocomial) problem. Several articles cover the current debate. There are some studies which seem to indicate that MRSA is alive and well within the community while others seem to indicate that the transmission is solely seen within the health care setting. In 2003, Jernegan et. al. conducted a prevalence study of MRSA colonization among patients presenting to a university hospital by performing surveillance cultures at the time of hospital admission. Of the 974 patients cultured, 21% had S. aureus isolated, and 26 (2.7%) had MRSA, representing 12.7% of all patients colonized. The independent predictors of MRSA colonization in the study's population were admission to a nursing home in the previous year or a hospitalization of 5 days or longer during the preceding year.

Because of the confounding data in competing studies, it is difficult to know who is right. It is important to remember in the review of these articles that the studies are based upon cultures taken and reported positive in less than 48 hours from the time of admission. As is noted, patients can be in an asymptomatic chronic carrier state with MRSA for months of even years, which makes it doubly hard to presume the reliability of this data.

An interesting study by Manian, et. al looked at the feasibility of screening all patients on routine basis for MRSA. The clients in this study where patients with a history of intravenous drug use who were being admitted to acute rehabilitation beds. Interestingly, Manian reported a 12% isolation rate for MRSA on newly admitted patients, and only 7% on those patients for in house transfers. It is not reported within these studies whether the patients who required transfer from the rehabilitation setting to a medical bed were transferred due to illness possibly associated with MRSA infections. It is known that a history of MRSA infection or colonization were independently associated with the positive screening cultures. But this only represented about 40% of patients who were admitted with MRSA positive cultures, and may speak for the value of routine cultures on all admissions, especially if the cost/procedure benefit is high.

One of the greatest problems identified in the literature, especially that as noted by wound care specialists, is that of the gap between literature and actual practice. An article by Bodenheimer in the New England Journal of Medicine recently noted that even physicians and other medical practitioners who are educated on the hard evidence and willing to change, there is very little follow through in the matter of the identification of and prevention of MRSA. Steps to improving care surrounding MRSA were identified in this article and included:

involve relevant people develop a proposal study the main difficulties in achieving change select a set of strategies/measures develop a budget.

One interesting study reviewed the use of maggots in the treatment of MRSA. While not specifically germane to the subject at hand, it will show what a significant problem this health care issue has become. In this study, it was felt that it was important to discover alternatives to antibiotic resistant wounds in which no other form of treatment appeared to suffice. The goal of the study was to find a way to combat wounds and promote a healing. Ultimately it was felt that maggot therapy has been seen to act on MRSA in wounds and constitutes another area in need of study, with greater emphasis on evidence-based practice (Courtney, Church and Ryan, 2000).

These results came from a small Brazilian study in which volunteers were tested using different cleaning agents after hands were minimally and then heavily contaminated with MRSA. It is interesting to note that the volunteers also used plain soap and a chlorhexadine solution. It should be noted however, that6 the study was relatively small, using only five volunteers and this significantly limits the data (Guilhermetti, 2001).
In Australia, a rigid screening and decolonization program has been helpful in decreasing the incidence of MRSA, although it continues to be a notable cause of hospitalization there. After an outbreak in a hospital in 1982 caused an epidemic, statutory notifications were enacted and several outbreaks were halted. It is interesting to note that there was a concurring incident of Ciprofloxacin resistance at the same time, but on the whole Australia has one of the lowest worldwide rates of multi-drug resistant MRSA thought to be in the most part due to their rigorous screening and surveillance programs. These programs have been so successful that there does not appear to be a significant presence of multi-drug resistant MRSA in any western Australian hospitals (McGuire, et al.).

Methodology

METHODS AND PROCEDURES: It is the hypothesis of this study that patients are more likely to become exposed to MRSA in the radiology department via multiuse items such as ultrasound probes using transdermal gel than with even more invasive radiological tools which undergo a more rigid and methodical cleaning program, such as the endoscopes used in the performance of endoscopic retrograde panreatoduodenoscopy.

The sample size estimates were based on the routine daily traffic throughout the radiology department in a small suburban hospital outside of a major metropolitan area. From a review of daily activity summaries, it was estimated that approximately 20 ultrasounds take place each day, while the rate or ERCP is one or less per week. To achieve a reasonable study population size, 100 study participants were needed. Patients will be identified via retrospective record review from data obtained from the local infection control committee, to whom all episodes of MRSA are reported for hospitalized and outpatient clients. A review of the patient history was done regarding medical history, current medication, lifestyle factors and family history. It was desirable for the patient population to be uniform in age (i.e. greater than 18 years and no greater than 70 years of age). We did not discern between inpatient and outpatients attending the radiology department, since the purpose of our study was not to determine whether the infection was nosocomial or community acquired, although it should be noted t hat the infection control committee of this institution did collect this data and would be willing to make it available to use for further study. For the purposes of HIPPA compliance, all personally identifying information was removed from the records before they were provided for the study staff, to include names, dates of birth, medical records number, social security number and other sensitive demographic information. The patients were simply identified by first and last initial and a two or three digit numeral, plus the modified "U" for those patients who had ultrasound and "E" for those who had had ERCP.

The study was retrospective in design. The study itself and took place over a 4-month period. Medical history checklists were developed by the study designer. Checklists were completed via chart review by a medical assistant hired specifically for the purpose. Medical history checklists were pre-tested on a group of individuals not enrolled in the study and evaluated for elements of clarity, reliability, sensitivity and interpretability. Study participants were not paid. Patients were screened for previous diagnosis of MRSA, either acute infection or as a carrier.

EVALUATION: Data collection was done by a review of all clinical material obtained. The presumed outcome (That multi-use radiological equipment which is cleaned using manual methods is more likely to be associated with transmission of MRSA than multi-use invasive equipment which is cleaned using rigid procedure and chemical disinfection) was compared to actual data collected. Possible confounding issues are previous unreported history of MRSA infection or colonization, patients who are not identified with infection during hospital stay or outpatient period of care.

Since the reporting…