MRSA may reside in healthy individuals and not cause any health problems. However hospital acquired infection can result in significant morbidity and mortality. The first case of MRSA was identified as early as 1961- 1962 shortly after introduction of Methicillin in 1960 [2–4]. MRSA has caused particular concern due to the resistance to standard antibiotics caused by gene mecA and the rapidity with which it spreads [2–5]. MRSA arose as a hospital based infection but has steadily spread to the community [4, 5]. Hospital acquired MRSA infection has been steadily increasing and in some reports infection rates have reached over 60% [4]. In this series we have identified an acquisition rate of 30% which is high. We believe this is because head and neck patients undergoing major surgery particularly at risk of this infection.
Head and neck cancer patients are prone to MRSA infection due to a number of factors such as: prolonged hospitalization, intravascular catheterization, compromised host immunity, malignancy, chemotherapy, radiotherapy surgery, prior antibiotic therapy and prolonged operative time [2–7]. Many of these factors were present in our series of patients. Following total laryngectomy, the mucosa of the trachea is permanently directly exposed to room air and we feel this site is particularly prone to MRSA infection. This is why the tracheal stoma was shown to be the commonest site of infection.
Serious postoperative complications related to MRSA infection have been identified in head and neck surgery patients with significant increase in morbidity [8, 9] number of surgical procedures and prolonged hospitalization time [10]. One of our patients had a carotid fistula or 'blow out' which is a life threatening complication. Colonisation of the tracheostomy site appeared to be the most important site of MRSA infection. The creation of a permanent tracheostomy following total laryngectomy may significantly reduce the patient's local defence mechanism allowing a conduit of infection to the aero-digestive tract.
PCF following laryngectomy constitutes a particularly serious complication with subsequent devastating medical, functional, psychological and economical effects. The rate ranges considerably from 8% to 40%, according to the literature [11–17]. A recently published meta-analysis of previously published studies on post-laryngectomy PCF concluded that the following four factors were thought to be significant: a) preoperative radiotherapy, b) postoperative haemoglobin level below 12.5 g/dl, c) prior tracheostomy, and d) preoperative radiotherapy and concurrent neck dissection [1]. Our study also has identified pre-operative radiotherapy as an important risk factor for PCF.
To our knowledge this is the first study to investigate and suggest a potential causal relationship between PCF and MRSA in patients undergoing total laryngectomy for laryngeal cancer. Whilst we have found a significantly higher MRSA infection rate in patients that have developed PCF following laryngectomy compared to those that did not, this association only implicates MRSA as a possible causative factor in. We recognise the limitations of this paper in that the design is retrospective and sample size small, however we feel the high incidence of MRSA infection seen in the PCF patients warrants further study.
The incidence of PCF in our laryngectomy patients was high (32%) compared to previously published series. The focus of future study in our institution is aimed at reducing this PCF rate.
MRSA principal mode of transmission is through direct contact via hospital personnel and by airborne transmission particularly from patients with tracheostomies [2–6]. Many strategies have been advocated to prevent MRSA infection with variable degree of evidence based, including search and destroy policy, restrictive antibiotic prescribing policy [12], hand hygiene with the use of alcohol- based solutions, isolation measures [13]. The high incidence of MRSA infection seen in this patient group obliged us to upgrade our infection control protocols and we have subsequently seen a dramatic reduction in MRSA infection rates.
There is some controversy regarding treating MRSA colonization versus infection particularly in hospital staff carriers and in endemic areas like UK, which can be proved to be difficult. However because of the particular risks associated with head and neck cancer patients, colonized patients should be eradicated prior to major surgery [10]. The current approach is to carry out preoperative screening and appropriate treatment by antiseptic skin washes, nasal mupirocin and chlorhexadine mouthwashes, isolation or barrier nursing and perioperative anti MRSA antibiotic in carrier patients, and judicious antibiotic prescription practice.
Having carried out this study, we have implemented an MRSA eradication protocol in all patients undergoing laryngectomy even if they are not colonized with MRSA in order to reduce infection rates. We have also seen a significant overall reduction in MRSA infection rates across the hospital due to strict hand hygiene, screening and MRSA eradication protocols being implemented.
MRSA will continue to pose a challenge because of rising incidence not only in hospitals and nursing homes but also in the outpatient community. The emergence of increasingly resistant staph. aureus organisms and the demand to treat patients with more and more complex medical conditions will continue to test medical and nursing staff in the future.
