Temporal effects of infection control practices and the use of antibiotics on the incidence of MRSA.

BACKGROUND: Meticillin-resistant Staphylococcus aureus (MRSA) has spread throughout the world and has become highly endemic worldwide. The need for implementing MRSA control strategies is no longer a matter of debate. AIM: To determine the temporal association between various infection control practices, the use of antibiotics and the incidence of MRSA in a 1200-bed French university hospital. METHODS: A multi-variate time-series analysis, based on monthly data from a nine-year period (January 2000-December 2008), was performed in a 1200-bed French university hospital to determine the temporal association between different variables and the incidence of MRSA. MRSA colonization pressure, infection control practices and use of antibiotics were considered in the analysis. FINDINGS: Time-series analysis showed a positive significant relationship between the incidence of hospital-acquired MRSA (HA-MRSA) and MRSA colonization pressure, the use of antibiotics (fluoroquinolones, macrolides and aminoglycosides) and the use of gloves. Conversely, a global negative correlation was observed between the incidence of HA-MRSA and the use of alcohol-based hand rub. Overall, the model explained 40.5% of the variance in the monthly incidence of MRSA. CONCLUSION: This study showed that admission of patients with MRSA, the use of antibiotics and infection control practices contributed to the incidence of HA-MRSA. This suggests that efforts should be focused on high compliance with hand disinfection. These results also raise concerns about the use of gloves when caring for patients with MRSA.

Tinción inmunohistoquímica p16 en carcinomas epidermoides del área genital y extragenital / Immunohistochemical Staining of p16 in Squamous Cell Carcinomas of the Genital and Extragenital Area

Introducción: La proteína p16 es una proteína supresora tumoral. El objetivo del estudio era comprobar si la tinción p16 se relaciona con la presencia de papilomavirus (subtipos mucosos o α, VPH-mc) en carcinomas epidermoides (CE) extragenitales (como ocurre en el cérvix y en CE genitales). Material y método: Se realizó tinción inmunohistoquímica con p16 a diversas lesiones incluidas en parafina del área genital (8 condilomas, tres CE intraepidérmicos y 7 CE invasores) y del área extragenital (20 CE intraepidérmicos tipo enfermedad de Bowen [EB] y 10 CE invasores). La detección de VPH-mc se realizó mediante reacción en cadena de la polimerasa (PCR). Resultados: En el área genital la tinción p16 fue negativa en los condilomas y positiva en los tres CE intraepidérmicos y en dos CE invasores (29%). Se detectó VPH-mc en 6 condilomas y dos CE intraepidérmicos (100%, excluyendo tres lesiones que no se pudieron estudiar con PCR) y en los dos CE invasores positivos para p16. En el área extragenital la tinción p16 fue positiva en 19 EB (95%) y en dos CE invasores (20%). Se detectó VPH-mc en 4 EB (tinción p16 positiva) y en un CE invasor (p16 negativa). En los CE intraepidérmicos la tinción p16 fue útil para objetivar si existían focos de microinfiltración dérmica o invasión de estructuras anexiales normales. Conclusiones: Según nuestros resultados la positividad de p16 es independiente de la detección de VPH en los CE extragenitales, al contrario de lo observado en CE genitales. En el área extragenital la pérdida de proteína p16 en los CE invasores respecto a los CE intraepidérmicos indicaría progresión tumoral (AU)

Background and objectives: Positive immunostaining for the tumor suppressor protein p16 is associated with the presence of mucosal or alfa subtypes of human papillomavirus (HPV) in cervical and genital squamous cell carcinoma (SCC). The aim of this study was to determine whether p16 immunostaining is also associated with mucosal HPV in extragenital SCC. Material and methods: Paraffin sections of lesions located in the genital region (8 genital warts, 3 intraepidermal SCCs, and 7 invasive SCCs) and extragenital area (29 intraepidermal SCCs corresponding to Bowen disease and 10 invasive SCCs) were stained for p16 by immunohistochemistry. Mucosal HPV was detected by polymerase chain reaction (PCR). Results: In the genital area, p16 immunostaining was negative in genital warts and positive in all 3 intraepidermal SCCs and 2 invasive SCCs (29%). Mucosal HPV was detected in 6 genital warts and 2 intraepidermal SCCs (100% after exclusion of 3 lesions that could not be analyzed by PCR) and in the 2 invasive SCCs that were positive for p16. In the extragenital area, 19 intraepidermal SCCs (95%) and 2 invasive SCCs (20%) were immunopositive for p16. Mucosal HPV was detected in 4 intraepidermal SCCs (p16 immunopositive) and 1 invasive SCC (p16 immunonegative). In intraepidermal SCCs, p16 immunostaining facilitated the identification of dermal microinfiltration or invasion of normal skin appendages. Conclusions: According to our results, unlike in genital SCCs, p16 immunopositivity is independent of the presence of HPV in extragenital SCCs. Compared with intraepidermal SCCs, the absence of p16 protein in invasive SCCs in the extragenital area would indicate progression of the disease (AU)

[Immunohistochemical staining of p16 in squamous cell carcinomas of the genital and extragenital area]. / Tinción inmunohistoquímica p16 en carcinomas epidermoides del área genital y extragenital.

BACKGROUND AND OBJECTIVES: Positive immunostaining for the tumor suppressor protein p16 is associated with the presence of mucosal or αsubtypes of human papillomavirus (HPV) in cervical and genital squamous cell carcinoma (SCC). The aim of this study was to determine whether p16 immunostaining is also associated with mucosal HPV in extragenital SCC. MATERIAL AND METHODS: Paraffin sections of lesions located in the genital region (8 genital warts, 3 intraepidermal SCCs, and 7 invasive SCCs) and extragenital area (29 intraepidermal SCCs corresponding to Bowen disease and 10 invasive SCCs) were stained for p16 by immunohistochemistry. Mucosal HPV was detected by polymerase chain reaction (PCR). RESULTS: In the genital area, p16 immunostaining was negative in genital warts and positive in all 3 intraepidermal SCCs and 2 invasive SCCs (29%). Mucosal HPV was detected in 6 genital warts and 2 intraepidermal SCCs (100% after exclusion of 3 lesions that could not be analyzed by PCR) and in the 2 invasive SCCs that were positive for p16. In the extragenital area, 19 intraepidermal SCCs (95%) and 2 invasive SCCs (20%) were immunopositive for p16. Mucosal HPV was detected in 4 intraepidermal SCCs (p16 immunopositive) and 1 invasive SCC (p16 immunonegative). In intraepidermal SCCs, p16 immunostaining facilitated the identification of dermal microinfiltration or invasion of normal skin appendages. CONCLUSIONS: According to our results, unlike in genital SCCs, p16 immunopositivity is independent of the presence of HPV in extragenital SCCs. Compared with intraepidermal SCCs, the absence of p16 protein in invasive SCCs in the extragenital area would indicate progression of the disease.

[Solar elastosis in cutaneous squamous cell carcinoma]. / Elastosis solar en carcinomas espinocelulares cutáneos.

INTRODUCTION: Solar elastosis, or basophilic degeneration of collagen, may be a histologic sign of chronic sun damage. MATERIAL AND METHODS: We reviewed 222 cases of squamous cell carcinoma (SCC) to identify the presence of solar elastosis and its possible invasion of the upper, middle, or deep reticular dermis. We also analyzed clinical variables such as SCC location, location in exposed areas of the skin, age, sex, and immunosuppression. Patients included had undergone surgical excision of an SCC. RESULTS: Severe solar elastosis was found in most cases (182 patients, 82%): 87 extended to the middle reticular dermis and 95 had reached the deep reticular dermis. Only 6 (2.7%) patients had no solar elastosis. In some cases elastosis was so severe that it had affected the subcutaneous cellular tissue or venous or arteriolar walls. Deeper solar elastosis was significantly associated with older age and female sex. CONCLUSIONS: Solar elastosis was found in most patients with SCC and seems to indicate chronic severe solar damage. Exposure to ultraviolet radiation would be the main cause of SCC, although other factors might also be implicated, particularly in patients who did not have severe solar elastosis. Systemic or localized immunosuppression was associated with nearly all the SCC cases studied, consistent with the marked immunosuppressant effects of sun exposure, the aging process, or both.

Elastosis solar en carcinomas espinocelulares cutáneos / Solar Elastosis in Cutaneous Squamous Cell Carcinoma

Introducción: El hallazgo de elastosis solar (degeneración basófila del colágeno) se podría considerar como un signo histológico del daño solar crónico. Material y método: Se ha realizado un estudio retrospectivo sobre 222 carcinomas espinocelulares (CE). Se ha valorado si existía elastosis solar y si esta se extendía hasta la dermis reticular superficial, media o profunda. También se han analizado otras variables clínicas como la localización, la ubuicación en áreas fotoexpuestas, así como la edad, el sexo y la inmunodepresión de los pacientes a los que se extirparon estos CE. Resultados: En la mayoría de CE (182CE, un 82%) se observa una intensa elastosis solar: 87CE presentaban elastosis solar hasta la dermis reticular media y 95CE hasta la dermis reticular profunda. Sólo hubo 6CE (2,7%) que no presentaban elastosis solar. En algunos CE la elastosis solar era tan intensa que se extendía hasta el tejido celular subcutáneo o afectaba a la pared de venas y/o arteriolas. Existía una relación significativa entre la observación de elastosis solar a más profundidad y una edad mayor, así como con el sexo femenino. Conclusiones: En la mayoría de CE se observa elastosis solar, lo que podría traducir un intenso daño solar crónico. La radiación ultravioleta sería el principal factor etiopatogénico en la mayoría de CE, aunque también podrían estar implicados otros factores etiopatogénicos, sobre todo en aquellos CE sin una elastosis solar intensa. Casi todos estos CE estudiados se asociarían a inmunodepresión (sistémica o localizada), basándonos en los importantes efectos inmunosupresores que producen las radiaciones solares, la edad avanzada o ambas (AU)

Introduction: Solar elastosis, or basophilic degeneration of collagen, may be a histologic sign of chronic sun damage. Material and methods: We reviewed 222 cases of squamous cell carcinoma (SCC) to identify the presence of solar elastosis and its possible invasion of the upper, middle, or deep reticular dermis. We also analyzed clinical variables such as SCC location, location in exposed areas of the skin, age, sex, and immunosuppression. Patients included had undergone surgical excision of an SCC. Results: Severe solar elastosis was found in most cases (182 patients, 82%): 87 extended to the middle reticular dermis and 95 had reached the deep reticular dermis. Only 6 (2.7%) patients had no solar elastosis. In some cases elastosis was so severe that it had affected the subcutaneous cellular tissue or venous or arteriolar walls. Deeper solar elastosis was significantly associated with older age and female sex. Conclusions: Solar elastosis was found in most patients with SCC and seems to indicate chronic severe solar damage. Exposure to ultraviolet radiation would be the main cause of SCC, although other factors might also be implicated, particularly in patients who did not have severe solar elastosis. Systemic or localized immunosuppression was associated with nearly all the SCC cases studied, consistent with the marked immunosuppressant effects of sun exposure, the aging process, or both (AU)

[Clear cells in cutaneous squamous cell carcinoma]. / Las células claras en el carcinoma espinocelular cutáneo.

INTRODUCTION: Although few cases of squamous cell carcinoma (SCC) with clear cells have been published, we believe that these cells are often present in SCC. MATERIAL AND METHODS: We studied 249 SCCs, analyzing a number of clinical and histological variables. Various immunohistochemical techniques (immunoperoxidase method) were used to determine whether adnexal differentiation was present. RESULTS: There were 96 SCCs with a proportion of clear cells of over 25 %. Advanced or established SCCs and SCCs associated with Bowen disease contained a larger proportion of clear cells. We defined 2 histological patterns: a) clear cells around the keratin pearls of SCCs arising from pre-existing actinic keratosis and with indirect signs of human papilloma virus infection in hair follicles; and b) clear cells that simulate adnexal differentiation in lesions arising on pre-existing Bowen disease lesions. There were also 19 carcinomas with true adnexal differentiation. DISCUSSION: Clear cells are frequently observed in SCC, though large numbers of clear cells are present only in certain SCCs. The appearance of clear cells in SCCs is progressive and they are only present in more advanced SCC. The presence of clear cells is suggestive of adnexal differentiation; however, in the majority of cases, their presence is due to infiltration of normal adnexal structures by the cells of pagetoid Bowen disease. True adnexal differentiation exists only in a small percentage of cases (7.6 % in our study). The histological pattern described as clear cells around keratin pearls practically rules out this differentiation.

[Epidermodysplasia verruciformis-like cells as histologic markers of immunosuppression: review of 229 squamous cell carcinomas]. / Las células tipo epidermodisplasia verruciforme como marcador histológico de inmunodepresión: revisión de 229 carcinomas espinocelulares.

INTRODUCTION: Epidermodysplasia verruciformis (EV) is associated with greater susceptibility to infection by certain oncogenic subtypes of human papillomavirus (HPV). Among other histologic findings, large, clear, oval or rounded cells (EV cells) are observed in the granular layer in EV, and some authors consider these cells to be markers of immunosuppression. MATERIAL AND METHODS: We analyzed 229 squamous cell carcinomas (SCC) to determine whether EV cells were present and to assess whether their presence was associated either with localized or cutaneous immunosuppression (tumors with signs of severe chronic actinic damage or severe stasis dermatitis) or with systemic immunosuppression (immunocompromised or elderly patients). RESULTS: We observed EV cells in 33 SCC. No statistically significant relationship was observed between the presence of EV cells and immunosuppression. We performed polymerase chain reaction in 8 lesions, but the results were not informative as the DNA was denatured. CONCLUSIONS: We found no relationship between the presence of EV cells and localized or systemic immunosuppression, possibly because the sample was inadequate (almost all SCC studied were associated with signs of immunosuppression, irrespective of the presence or absence of EV cells). Further studies will be required to compare lesions associated with immunosuppression with those in which immunosuppression is absent. The presence of EV cells may be the result of cytopathic effects of certain HPV subtypes, such as HPV 5 or 8, but this will need to be demonstrated using techniques such as polymerase chain reaction.

Temporal relationship between prevalence of meticillin-resistant Staphylococcus aureus (MRSA) in one hospital and prevalence of MRSA in the surrounding community: a time-series analysis.

We studied the relationship between meticillin-resistant Staphylococcus aureus (MRSA) prevalence in the Aberdeen Royal Infirmary and in the surrounding community (Grampian region: 500 000 inhabitants). We calculated the monthly %MRSA for both hospital and community from January 1996 to February 2002. A dynamic regression model was adjusted to measure any relationship between both series. The monthly %MRSA in the community was strongly related to the monthly %MRSA observed one month before in the hospital (R(2)=90.8%). We found no relationship with antimicrobial community use, although we have previously reported a strong correlation between prior use of antibiotics and incidence of MRSA in the hospital. By using time-series analysis techniques, we demonstrated that variations in MRSA prevalence in the hospital are quickly followed by similar variations in MRSA prevalence in the surrounding community. These results suggest that the reason for the increase in MRSA prevalence in the community was a hospital MRSA outbreak. Screening at patient discharge should be evaluated as a new measure to control spread of MRSA in the community.

[Surveillance of antimicrobial resistance and antimicrobial use in a university-affiliated hospital: implementation of a computerized system]. / Mise en place d'un outil informatisé de surveillance de la résistance bactérienne et de la consommation antibiotique dans un centre hospitalier universitaire.

UNLABELLED: After half a century of antibiotic use, the increasing problem of the emergence and spread of antimicrobial-resistant pathogens has created a problem of public health. The causes of this problem are multifactorial, but the excessive and inappropriate use of antimicrobials is the principal cause. The current guidelines for the control of antimicrobial resistance in hospitals recommend the implementation of a surveillance system of antimicrobial use and antimicrobial resistance data. AIM OF THE STUDY: The objective of our project was to develop a computerised tool to survey the antibiotic consumption data and the antimicrobial resistance. MATERIALS AND METHODS: We have collected antimicrobial resistance data from the software of the bacteriology laboratory, antibiotic use data from the pharmacy and demographical data from the hospital's admission department. These data were integrated in a database server and available with a web application. Antimicrobial resistance data of 15 major microorganisms were extracted and expressed as a frequency with elimination of repeats by using time criteria (7, 14 or 28 days). Antibiotic use data were converted into defined daily doses (DDD) and expressed per 1000 patient-days. RESULTS: Data are available for consultation in the form of tables or graphs per unit, type of units (medicine, surgery, pediatrics, intensive care units) or in the whole hospital. The system allows the confrontation on the same graph of antimicrobial resistance and antibiotic use data. CONCLUSION: Our surveillance system constitutes a needed prerequisite to the implementation of a global strategy of antibiotic use improvement in our hospital.

Influence of various criteria for elimination of duplicates when calculating the prevalence and antibiotic susceptibility of microorganisms associated with urinary infections.

The effect of applying various criteria for elimination of repeated isolates in the same patient on the prevalence and antibiotic susceptibility of microorganisms frequently associated with urinary infections were analyzed. When time criteria were applied, there was a decrease in the number of isolates of 13.4-27.5%, whereas when variations in antibiotic susceptibility were considered, between 4.3 and 20.3% of the isolates were eliminated. The absolute number of isolates varied considerably depending on which of these two criteria were used, but neither criterion was seen to modify significantly the antibiotic susceptibility of these microorganisms and this confirms the recommendations of the NCCLS for this group of pathogens.

Relationship between ceftriaxone use and resistance to third-generation cephalosporins among clinical strains of Enterobacter cloacae.

OBJECTIVE: To investigate the potential correlation between the use of extended-spectrum cephalosporins (ESCs) and resistance to this antibiotic class among clinical isolates of Enterobacter cloacae in a university-affiliated hospital. MATERIALS AND METHODS: Data on antimicrobial resistance and antimicrobial use concerning E. cloacae and ESCs were collected over a 4 year period. Various statistical tools were used to explore the potential relationship. RESULTS: From 1999 to 2002, the proportion of E. cloacae isolates resistant to ESCs increased from 24.3% to 29.6%. (P=0.04), and the quantity of ESCs prescribed and given did not change. Within the subclass constituted by first-line ESCs, the proportion of ceftriaxone increased from 64.3% to 77.6% and the proportion of cefotaxime decreased accordingly, from 35.7% to 22.4%. Statistical analyses showed that E. cloacae resistance to ESCs correlated with ceftriaxone use regardless of the other ESCs. For every defined daily dose of ceftriaxone per 1000 patient days used in our hospital, resistance of E. cloacae isolates to ESCs increased by 1.36%. CONCLUSION: This study demonstrates a specific correlation between ceftriaxone use and the development of resistance in E. cloacae clinical isolates. The high biliary elimination of ceftriaxone compared with other ESCs may be responsible for a greater impact of this antibiotic on the digestive flora.

Modelling and forecasting antimicrobial resistance and its dynamic relationship to antimicrobial use: a time series analysis.

To investigate the relationship between antimicrobial use and resistance in our hospital, we collected antimicrobial susceptibility and use data from existing microbiology laboratory and pharmacy databases for the period July 1st, 1991-December 31, 1998. The data was analyzed as time series and autoregressive integrated moving average (Box-Jenkins) and transfer function models were built. By using this method, we were able to demonstrate a temporal relationship between antimicrobial use and resistance, to quantify the effect of use on resistance and to estimate the delay between variations of use and subsequent variations in resistance. The results obtained for two antimicrobial-microorganism combinations: ceftazidime-gram-negative bacilli and imipenem-Pseudomonas aeruginosa, are shown as examples.

[Arterial pressure in 1- to 4-year-old school children]. / Tensión arterial en niños de uno a cuatro años escolarizados.

Systolic and diastolic blood pressures have been evaluated in 645 school children aged 1 to 4 years old. Mercury-gravity manometer was used, and diastolic pressure was assessed taking Korotkoff is fifth phase. Blood pressure with sex, age, body height and body weight was correlated. There was no significant difference of tension values between both sexes. Diastolic blood pressure increased progressively and notoriously for each age interval (12 months) in both sexes. Systolic blood pressure increased notoriously only in the 3 and 4 years girls group. The partial correlation and stepwise regression analyses of variables age, body height and body weight with blood pressure showed that body weight was the only variable significantly related to systolic in both sexes, while body weight and age in boys and none of them in girls with the diastolic.

[Arterial blood pressure in the term neonate in the first month of life]. / Tensión arterial del recién nacido a término en el primer mes de la vida.

Systolic blood pressure was valued by Doppler method, in 162 healthy full-term newborn at 48 hours of live, repeated in 134 in the second week and in 120 at the end of first month. A significant increase of systolic blood pressure along all the period with a strong increment in the first week was observed. Authors studied influences on blood pressure of the variabilities: weight, height, gestational age and heart rate. At 48 hours variability with a rate of correlation, weight was higher at birth (r = 0.324, p less than 0.001). There was not evident and significant relation with gestational age. Systolic blood pressure codes were lower when sleeping than when awake. Empirical percentiles of blood pressure are shown during first month of life.