[Multiple abscesses in immunocompetent patients caused by Panton-Valentine leukocidin positive Staphylococcus aureus]

Panton-Valentine Leukocidin-Producing Staphylococcus aureus Infection: A Case Series

Panton-Valentine leukocidin-producing Staphylococcus aureus (PVL-SA) is associated with relapsing multifocal skin and soft tissue infections (SSTI), necrotizing pneumonia (NP) and severe musculoskeletal infections. Epidemiology is underknown and underdiagnosis is likely. Recent travel abroad, case clustering and relapsing disease are often reported. We reviewed all cases of PVL-SA infection diagnosed at our center, and found 21 cases over a 43-month period. Most patients were adult males, had relevant travel history, reported recurrent disease and presented with SSTI. Etiologic diagnosis took up to five years; meanwhile, 42% of patients had antibiotic treatments. Draining procedures were required in 43% of patients and intensive care support in 19%. All patients recovered. Methicillin-resistance prevalence was 24%. Only 2/13 decolonized patients had posterior relapsing SSTI, both with likely infected contacts. PVL-SA infection’s severity and impact are clear, even in small case series as ours. Physician awareness and active PVL-gene search are crucial for an adequate management.

Recurrent mucocutaneous infections caused by PVL-positive Staphylococcus aureus strains: a challenge in clinical practice

BACKGROUND

Recurrent mucocutaneous infections caused by PVL-positive Staphylococcus (S.) aureus strains represent an increasing problem in Germany. Although there have been several outbreaks at day care centers and in urban communities in recent years, there are currently no diagnostic algorithms or treatment recommendations for these particular infections in Germany.

METHODS

We performed a literature search in the PubMed/MEDLINE database with the goal of developing an algorithm for diagnosis and treatment of these infections. National and international recommendations were also considered.

RESULTS

Panton-Valentine leukocidin (PVL) is a pore-forming protein produced by certain S. aureus strains. Both methicillin-susceptible (MSSA) and methicillin-resistant S. aureus (MRSA) strains may carry the lukS-lukF gene responsible for PVL production. The clinical presentation of infections caused by PVL-positive S. aureus ranges from isolated recurrent abscesses to extensive furunculosis. Despite adequate treatment of primary infections, approximately 40 % of patients develop recurrent disease. The choice of treatment regimen is guided by the clinical presentation of the infection. In addition, some scientific literature recommends bacteriological screening of patients and their contacts, followed by decolonization of affected individuals.

CONCLUSIONS

The present article focuses on the pathogenesis and risk factors of recurrent mucocutaneous infections caused by PVL-positive S. aureus strains and proposes a diagnostic and therapeutic algorithm for optimal patient care.

Community-acquired skin infections caused by Staphylococcus aureus: What is the role of the Panton-Valentine leukocidin toxin?

BACKGROUND

The data concerning frequency and relevance of the toxin Panton-Valentine leukocidin (PVL) in skin infections caused by Staphylococcus aureus is controversial. The objective of the study was the identification of the role of the toxin in community-acquired skin infections caused by S. aureus.

PATIENTS AND METHODS

We performed a retrospective analysis of 112 patients with the diagnosis of skin infections caused by S. aureus. Frequency of PVL was investigated by PCR for the lukSF gene. Risk factors and severity of the disease were analyzed. Furthermore, spa typing was done in 55 of the isolated S. aureus.

RESULTS

PVL occurred in 45 % of patients with skin infections caused by methicillin-susceptible S. aureus; methicillin-resistant strains were positive in 63 %. Mean age was 30.9 years in PVL-positive infections and thus statistically highly significantly lower than in PVL-negative infections. There was no correlation between presence of PVL and severity and course of skin infections or presence of special risk factors. The spa types showed a high variability in PVL-positive as well as in PVL-negative strains.

CONCLUSIONS

In our study the PVL status of S. aureus isolated from skin infections was neither correlated with methicillin-resistance nor with the severity of disease. Remarkably, PVL-positive S. aureus strains appeared to be more frequent in younger than in older patients. Our results demonstrate that routine determination of PVL status is not required since the outcome has no diagnostic or therapeutic consequences in daily dermatological practice.

The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in Germany

BACKGROUND

For decades, methicillin-resistant Staphylococcus aureus (MRSA) has been a major cause of infection in hospitals and nursing homes (health care-associated MRSA, HA-MRSA). Beginning in the late 1990s, many countries have also experienced a rising incidence of MRSA infection outside of the health care setting (community-associated MRSA, CA-MRSA). Moreover, animal reservoirs are increasingly considered to represent an important source of human MRSA acquisition. In this review article the authors describe the current epidemiological situation of MRSA in Germany.

METHODS

This review is based on pertinent articles published up to 2010 that were retrieved by a selective PubMed search, as well as on publications issued by national reference institutions up to 2010.

RESULTS

There are about 132 000 cases of MRSA in German hospitals each year. MRSA is found in about 18% to 20% of all inpatient-derived culture specimens that are positive for S. aureus. CA-MRSA is not yet endemic in Germany; important risk factors for its acquisition include travel to high-prevalence areas and household contact with persons that harbor a CA-MRSA infection. Agricultural livestock is the main animal reservoir for MRSA, which is often zoonotically transmitted from animals to human beings by direct contact. However, both CA-MRSA and MRSA from animal reservoirs can be imported into hospitals and cause nosocomial infections.

CONCLUSION

Hospitals and nursing homes were once the main reservoirs of MRSA, but new ones have now emerged outside of the healthcare setting. Efforts to prevent MRSA and limit its spread must rise to this new challenge.