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Biomedical subjects

T L Barrett

Publications and source records attributed to T L Barrett.

At least 37 records · Page 2Linked to original sources

Histologic and immunohistochemical features in biopsy sites in which bovine collagen matrix was used for hemostasis.

BACKGROUND: Bovine collagen matrix (Helistat and Helatene), which is used primarily for hemostasis, decreases wound contracture in skin biopsy sites and promotes wound granulation. OBJECTIVE: Our purpose was to evaluate excision specimens of previous biopsy sites to determine whether there are histologic differences between cases in which bovine collagen matrix was used for hemostasis and those in which it was not used. METHODS: Thirty-two diagnostic punch biopsies were done with hemostasis obtained with bovine collagen matrix in 24 biopsies and by pressure alone in eight. The biopsy sites were reexcised at various time intervals, and the histologic and immunohistochemical features were evaluated and compared. RESULTS: In specimens in which collagen matrix was used, migration of stromal and epithelial cells along the bovine collagen matrix was evident by 2 days and had progressed rapidly by 4 days. Around and within the matrix hyaluronic acid increased during the first 8 to 10 days. Initially stromal cells stained with CD34 and reticulum fibers were present at 8 to 10 days. AT 12 to 15 days, factor XIIIa+ stromal cells were present within the matrix, and host collagen fibers were present and well-oriented within the degenerating matrix. Biopsy specimens allowed to heal without the matrix showed a delayed and an uneven increase in hyaluronic acid. Furthermore, the granulation tissue within the dermis showed no organization with a persistent acute inflammatory infiltrate and increased muscle actin-positive stromal cells as scar formation proceeded. CONCLUSION: Bovine collagen products appear to provide a matrix that promotes thrombosis. The collagen matrix also promotes migration and attachment of stomal and epithelial cells, thereby organizing and accelerating wound healing.

Actins↗

Cutaneous pseudosarcomatous polyp: a histological and immunohistochemical study.

Two unusual acquired polypoid skin lesions exhibited prominent histological atypia, but were biologically benign. Both patients were elderly females. The lesions clinically mimicked fibroepithelial polyp or nevus lipomatosus. Both had been present for about 20 years. One lesion was located on the back, the other on the posterior thigh. Each lesion exhibited dilated, hyalinized vessels in the dermis with focal fibrin deposits, myxoid stroma, and a population of bizarre, pleomorphic spindle to stellate cells, some of which were multinucleated. Occasional atypical mitoses were present. One lesion had abundant admixed fat. Immunohistochemical staining was strongly positive only for vimentin. The lesions share features with degenerating angiofibroma and vaginal pseudosarcomatous polyp. As in these lesions, the atypia is most probably reactive and degenerative.

Aged↗

Ossifying fibromyxoid tumor of soft parts: a case report and review.

Ossifying fibromyxoid tumor of soft parts is a recently described, rare but morphologically distinctive tumor of soft tissue, including subcutaneous soft tissue. We report a case of ossifying fibromyxoid tumor of soft parts which occurred in the subcutaneous tissue of a 68-year-old male, and review the clinical, histologic, and immunohistologic features of this tumor. Ossifying fibromyxoid tumor of soft parts tends to occur in the subcutaneous tissue and have been reported from the head and neck, upper and lower extremities, and trunk. Immunohistologic studies have supported a neural origin. While considered benign, local recurrence after excision is common and these tumors should be excised with clear margins to prevent recurrence.

Aged↗

Quality standard for antimicrobial prophylaxis in surgical procedures. The Infectious Diseases Society of America.

OBJECTIVE: The objectives of this quality standard are 1) to provide an implementation mechanism that will facilitate the reliable administration of prophylactic antimicrobial agents to patients undergoing operative procedures in which such a practice is judged to be beneficial and 2) to provide a guideline that will help local hospital committees formulate policies and set up mechanisms for their implementation. Although standards in the medical literature spell out recommendations for specific procedures, agents, schedules, and doses, other reports document that these standards frequently are not followed in practice. OPTIONS: We have specified the procedures in which the administration of prophylactic antimicrobial agents has been shown to be beneficial, those in which this practice is widely thought to be beneficial but in which compelling evidence is lacking, and those in which this practice is controversial. We have examined the evidence regarding the optimal timing of drug administration, the optimal dose, and the optimal duration of prophylaxis. OUTCOMES: The intended outcome is more uniform and reliable administration of prophylactic antibiotics in those circumstances where their value has been demonstrated or their use has been judged by the local practicing medical community to be desirable. The result should be a reduction in rates of postoperative wound infection with a limitation on the quantities of antimicrobial agents used in circumstances where they are not likely to help. EVIDENCE: Many prospective, randomized, controlled trials comparing placebo with antibiotic and comparing one antibiotic with another have been conducted. In addition, some trials have compared the efficacy of different doses or methods of administration. Other papers have reported on the apparent efficacy of administration at different times and on actual practice in specific communities. Only a small group of relevant articles found through 1993 are cited herein. When authoritative reviews are available, these--rather than an exhaustive list of original references--are cited. VALUES: We assumed that reducing rates of postoperative infection was valuable but that reducing the total amount of antimicrobial agents employed was also worthwhile. The cost of and morbidity attributable to postoperative wound infections should be weighed against the cost and potential morbidity associated with excessive use of antimicrobial agents. BENEFITS, HARMS, AND COSTS: More reliable administration of antimicrobial agents according to recognized guidelines should prevent some postoperative wound infections while lowering the total quantity of these drugs used. No harms are anticipated. The costs involved are those of the efforts needed on a local basis to design and implement the mechanism that supports uniform and reliable administration of prophylactic antibiotics. RECOMMENDATIONS: All patients for whom prophylactic antimicrobial agents are recommended should receive them. The agents given should be appropriate in light of published guidelines. A short duration of prophylaxis (usually < 24 hours) is recommended. VALIDATION: More than 50 experts in infectious disease and 10 experts in surgical infectious disease and surgical subspecialties reviewed the standard. In addition, the methods for its implementation were reviewed by the American Society of Hospital Pharmacists. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Disease Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (Drs. Gross and McGowan), the Society for Hospital Epidemiology of America (Dr. Wenzel), the Surgical Infection Society (Dr. Dellinger), the Pediatric Infectious Disease Society (Dr. Krause), the Centers for Disease Control and Prevention (Dr. Martone), the Obstetrics and Gynecology Infectious Diseases Society (Dr. Sweet), and the Association of Practitioners of Infection Contr

Anti-Bacterial Agents↗

Quality standard for the treatment of bacteremia. The Infectious Diseases Society of America.

OBJECTIVE: The objective of this quality standard is to optimize the treatment of bacteremia in hospitalized patients by ensuring that the antibiotic given is appropriate in terms of the blood culture susceptibility of the pathogen. Although this standard may appear to be minimal in scope, it is needed because appropriate antimicrobial treatment is not given in 5% to 17% of cases. To implement the standard, physicians, pharmacists, and microbiologists will need to devise a coordinated strategy. OPTIONS: We considered criteria for appropriate dosing, most cost-effective selection, proper antibiotic levels in serum, least toxicity, narrowest spectrum, specific clinical indications, and optimal duration of treatment. All these criteria were rejected as the basis for the standard because they were too controversial and too difficult to be applied by a nonphysician chart reviewer. In contrast, the selection of an antibiotic to which the pathogen is sensitive is a noncontroversial criterion and easy for a chart reviewer to apply. OUTCOMES: The standard is designed to reduce the incidence of adverse outcomes of septicemia such as renal failure, prolonged hospitalization, and death. EVIDENCE: Several well-designed clinical trials without randomization as well as case-controlled studies have confirmed the benefit of using an antibiotic that is appropriate in light of the susceptibility of the isolate in blood culture. Prospective, randomized, placebo-controlled trials are not available. VALUES: Our premise is that the presence of bacteremia is a risk factor for serious adverse outcomes. We also believe that the administration of antibiotics must always be guided by the susceptibility report for the pathogen(s) obtained from blood cultures. This concern is more critical for pathogens from the blood than for those from most other body sites. We had evidence that susceptibility reports for pathogens from positive blood cultures were not always used properly. We used group discussion to reach a consensus among the members of the Quality Standards Subcommittee. BENEFITS, HARMS, AND COSTS: Through the implementation of this standard, at least 5% of bacteremias could be treated more appropriately. An unknown number of deaths would likely be prevented, and mortality from bacteremia treated inappropriately would probably be reduced. The primary undesirable feature of the standard is an increased workload of pharmacists and microbiologists. RECOMMENDATIONS: Treatment of bacteremia with an antibiotic that is appropriate in terms of the pathogen's blood-culture susceptibility is a minimal standard of care for all patients. VALIDATION: We consulted more than 50 experts in infectious diseases from the fields of medicine, surgery, pediatrics, obstetrics and gynecology, nursing, epidemiology, pharmacology, and government. In addition, the methods for its implementation were reviewed by the American Society of Hospital Pharmacists and were tested by one of the members of the Quality Standards Subcommittee. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Diseases Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (Drs. Gross and McGowan), the Society for Hospital Epidemiology of America (Dr. Wenzel), the Surgical Infection Society (Dr. Dellinger), the Pediatric Infectious Diseases Society (Dr. Krause), the Centers for Disease Control and Prevention (Dr. Martone), the Obstetrics and Gynecology Infectious Diseases Society (Dr. Sweet), and the Association of Practitioners of Infection Control (Ms. Barrett). Funding was provided by the IDSA and the other cooperating organizations. This standard is endorsed by the IDSA.

Anti-Bacterial Agents↗

Quality standard for assurance of measles immunity among health care workers. The Infectious Diseases Society of America.

OBJECTIVE: The objective of this quality standard is to prevent nosocomial transmission of measles by assuring universal measles-mumps-rubella (MMR) vaccination of all health care workers who lack immunity to measles. Although the primary emphasis is on health care workers in hospitals, those at other sites, such as clinics, nursing homes, and schools, are also included. It will be the responsibility of designated individuals at these institutions to implement the standard. OPTIONS: We considered advocating the use of measles vaccine rather than MMR but chose the latter because it also protects against mumps and rubella and because it is more readily available. OUTCOMES: The desired outcome is a reduction in the nosocomial transmission of measles. EVIDENCE: Although direct comparative studies are lacking, nosocomial outbreaks of measles have been reported (as recently as 1992) in institutions where measles immunization of nonimmune health care workers is not universal, whereas such outbreaks have not been reported in institutions with universal immunization. VALUES AND VALIDATION: We consulted more than 50 infectious-disease experts in epidemiology, government, medicine, nursing, obstetrics and gynecology, pediatrics, and surgery. In light of disagreement regarding the implementation of the standard, we used group discussions to reach a consensus. BENEFITS, HARMS, AND COSTS: The consequences of the transmission of measles (and of mumps and rubella) in a health care institution include not only the morbidity and mortality attributable to the disease, but also the significant cost of evaluating and containing an outbreak and the serious disruption of regular hospital routines when control measures are instituted. The potential harm to health care workers after the implementation of the standard consists of untoward effects of MMR vaccine, although the reactions of vaccines should be minimal with adherence to recommended vaccination procedures. Implementation of the standard should entail no expense to health care workers; the precise cost to institutions is unknown, but the expense would be mitigated by prevention of measles outbreaks. RECOMMENDATIONS: We recommend MMR vaccination of all health care workers who lack immunity to measles. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Diseases Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (Drs. Gross and McGowan), the Society for Hospital Epidemiology of America (Dr. Wenzel), the Surgical Infection Society (Dr. Dellinger), the Pediatric Infectious Diseases Society (Dr. Krause), the Centers for Disease Control and Prevention (Dr. Martone), the Obstetrics and Gynecology Infectious Diseases Society (Dr. Sweet), and the Association of Practitioners of Infection Control (Ms. Barrett). Funding was provided by the IDSA and the other cooperating organizations. The standard is endorsed by the IDSA.

Cross Infection↗

Quality standard for antimicrobial prophylaxis in surgical procedures. Infectious Diseases Society of America.

OBJECTIVE: The objectives of this quality standard are (1) to provide an implementation mechanism that will facilitate the reliable administration of prophylactic antimicrobial agents to patients undergoing operative procedures in which such a practice is judged to be beneficial and (2) to provide a guideline that will help local hospital committees formulate policies and set up mechanisms for their implementation. Although standards in the medical literature spell out recommendations for specific procedures, agents, schedules, and doses, other reports document that these standards frequently are not followed in practice. OPTIONS: We have specified the procedures in which the administration of prophylactic antimicrobial agents has been shown to be beneficial, those in which this practice is widely thought to be beneficial but in which compelling evidence is lacking, and those in which this practice is controversial. We have examined the evidence regarding the optimal timing of drug administration, the optimal dose, and the optimal duration of prophylaxis. OUTCOMES: The intended outcome is more uniform and reliable administration of prophylactic antibiotics in those circumstances where their value has been demonstrated or their use has been judged by the local practicing medical community to be desirable. The result should be a reduction in rates of postoperative wound infection in conjunction with a limitation on the quantities of antimicrobial agents used in circumstances where they are not likely to help. EVIDENCE: Many prospective, randomized, controlled trials comparing placebo with antibiotic and comparing one antibiotic with another have been conducted. In addition, some trials have compared the efficacy of different doses or methods of administration. Other papers have reported on the apparent efficacy of administration at different times and on actual practice in specific communities. Only a small group of relevant articles found through 1993 are cited herein. When authoritative reviews are available, these--rather than an exhaustive list of original references--are cited. VALUES: We assumed that reducing rates of postoperative infection was valuable but that reducing the total amount of antimicrobial agents employed was also worthwhile. The cost of and morbidity attributable to postoperative wound infections should be weighted against the cost and potential morbidity associated with excessive use of antimicrobial agents. BENEFITS, HARMS, AND COSTS: More reliable administration of antimicrobial agents according to recognized guidelines should prevent some postoperative wound infections while lowering the total quantity of these drugs used. No harms are anticipated. The costs involved are those of the efforts needed on a local basis to design and implement the mechanism that supports uniform and reliable administration of prophylactic antibiotics. RECOMMENDATIONS: All patients for whom prophylactic antimicrobial agents are recommended should receive them. The agents given should be appropriate in light of published guidelines. A short duration of prophylaxis (usually < 24 hours) is recommended. VALIDATION: More than 50 experts in infectious diseases and 10 experts in surgical infectious diseases and surgical subspecialties reviewed the standard. In addition, the methods for its implementation were reviewed by the American Society of Hospital Pharmacists. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Diseases Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (P.A.G. and J.E.M.), the Society for Hospital Epidemiology of America (R.P.W.), the Surgical Infection Society (E.P.D.), the Pediatric Infectious Diseases Society (P.J.K.), the Centers for Disease Control and Prevention (W.J.M.), the Obstetrics and Gynecology Infectious Diseases Society (R.L.S.), and the Association of Practitioners of Infection Control (T.

Anti-Bacterial Agents↗

Quality standard for the treatment of bacteremia. Infectious Diseases Society of America.

OBJECTIVE: The objective of this quality standard is to optimize the treatment of bacteremia in hospitalized patients by ensuring that the antibiotic given is appropriate in terms of the blood culture susceptibility of the pathogen. Although this standard may appear to be minimal in scope, it is needed because appropriate antimicrobial treatment is not given in 5%-17% of cases. To implement the standard, physicians, pharmacists, and microbiologists will need to devise a coordinated strategy. OPTIONS: We considered criteria for appropriate dosing, most cost-effective selection, proper antibiotic levels in serum, least toxicity, narrowest spectrum, specific clinical indications, and optimal duration of treatment. All these criteria were rejected as the basis for the standard because they were too controversial and too difficult to be applied by a nonphysician chart reviewer. In contrast, the selection of an antibiotic to which the pathogen is sensitive is a noncontroversial criterion that is easy for a chart reviewer to apply. OUTCOMES: The standard is designed to reduce the incidence of adverse outcomes of septicemia, such as renal failure, prolonged hospitalization, and death. EVIDENCE: Several well-designed clinical trials without randomization as well as case-controlled studies have confirmed the benefit of using an antibiotic that is appropriate in light of the susceptibility of the isolate in blood culture. Prospective, randomized, placebo-controlled trials are not available. VALUES: Our premise is that the presence of bacteremia is a risk factor for serious adverse outcomes. We also believe that the administration of antibiotics must always be guided by the susceptibility report for the pathogen(s) obtained from blood cultures. This concern is more critical for pathogens from the blood than for those from most other body sites. We had evidence that susceptibility reports for pathogens from positive blood cultures were not always used properly. We used group discussion to reach a consensus among the members of the Quality Standards Subcommittee. BENEFITS, HARMS, AND COSTS: Through the implementation of this standard, at least 5% of cases of bacteremia could be treated more appropriately. An unknown number of deaths would likely be prevented, and mortality from bacteremia treated inappropriately would probably be reduced. The primary undesirable feature of the standard is an increased workload for pharmacists and microbiologists. RECOMMENDATIONS: Treatment of bacteremia with an antibiotic that is appropriate in terms of the pathogen's blood-culture susceptibility is a minimal standard of care for all patients. VALIDATION: We consulted more than 50 experts in infectious diseases from the fields of medicine, surgery, pediatrics, obstetrics and gynecology, nursing, epidemiology, pharmacology, and government. In addition, the methods for its implementation were reviewed by the American Society of Hospital Pharmacists and were tested by one of the members of the Quality Standards Subcommittee. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Diseases Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (P.A.G. and J.E.M.), the Society for Hospital Epidemiology of America (R.P.W.), the Surgical Infection Society (E.P.D.), the Pediatric Infectious Diseases Society (P.J.K.), the Centers for Disease Control and Prevention (W.J.M.), the Obstetrics and Gynecology Infectious Diseases Society (R.L.S.), and the Association of Practitioners of Infection Control (T.L.B.). Funding was provided by the IDSA and the other cooperating organizations. The standard is endorsed by the IDSA.

Anti-Bacterial Agents↗

Quality standard for assurance of measles immunity among health care workers. Infectious Diseases Society of America.

OBJECTIVE: The objective of this quality standard is to prevent nosocomial transmission of measles by assuring universal measles-mumps-rubella (MMR) vaccination of all health care workers who lack immunity to measles. Although the primary emphasis is on health care workers in hospitals, those at other sites, such as clinics, nursing homes, and schools, are also included. It will be the responsibility of designated individuals at these institutions to implement the standard. OPTIONS: We considered advocating the use of measles vaccine rather than MMR vaccine but chose the latter because it also protects against mumps and rubella and because it is more readily available. OUTCOMES: The desired outcome is a reduction in the nosocomial transmission of measles. EVIDENCE: Although direct comparative studies are lacking, nosocomial outbreaks of measles have been reported (as recently as 1992) in institutions where measles immunization of nonimmune health care workers is not universal, whereas such outbreaks have not been reported in institutions with universal immunization. VALUES AND VALIDATION: We consulted more than 50 infectious-disease experts from the fields of epidemiology, government, medicine, nursing, obstetrics and gynecology, pediatrics, and surgery. In light of disagreement regarding the implementation of the standard, we used group discussions to reach a consensus. BENEFITS, HARMS, AND COSTS: The consequences of the transmission of measles (and of mumps and rubella) in a health care institution include not only the morbidity and mortality attributable to the disease but also the significant cost of evaluating and containing an outbreak and the serious disruption of regular hospital routines when control measures are instituted. The potential harm to health care workers after the implementation of the standard consists of untoward effects of MMR vaccine, although the reactions of vaccinees should be minimal with adherence to recommended vaccination procedures. Implementation of the standard should entail no expense to health care workers; the precise cost to institutions is unknown, but the expense would be mitigated by the prevention of measles outbreaks. RECOMMENDATIONS: We recommend MMR vaccination of all health care workers who lack immunity to measles. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Diseases Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (P.A.G. and J.E.M.), the Society for Hospital Epidemiology of America (R.P.W.), the Surgical Infection Society (E.P.D.), the Pediatric Infectious Diseases Society (P.J.K.), the Centers for Disease Control and Prevention (W.J.M.), the Obstetrics and Gynecology Infectious Diseases Society (R.L.S.), and the Association of Practitioners of Infection Control (T.L.B.). Funding was provided by the IDSA and the other cooperating organizations. The standard is endorsed by the IDSA.

Cross Infection↗

Spindle cell neoplasms coexpressing cytokeratin and vimentin (metaplastic squamous cell carcinoma).

Spindle cell squamous carcinoma (SCSC) and atypical fibroxanthoma (AFX) are both spindle cell neoplasms (SCN) that usually arise in areas of solar or ionizing radiation of elderly patients. Both lesions have a similar biologic behavior. In addition, the morphologic and ultrastructural similarities found in AFX and the spindle cell component of SCSC, have led some investigators to conclude that these tumors have a similar cell of origin. We studied 15 SCNs with no evidence of epithelial origin and no morphologic epithelial component, that showed immunohistochemical and ultrastructural evidence that would support metaplastic changes of a squamous cell carcinoma to a neoplasm with mesenchymal characteristics.

Aged↗

HMB-45 staining in benign and malignant melanocytic lesions. A reflection of cellular activation.

The antibody HMB-45 used as an immunohistochemical reagent has often been labeled as a marker for melanoma, even though some benign lesions have been noted to show positive staining reactions with this reagent. Biopsy specimens from 225 benign and malignant melanocytic lesions were examined after immunoperoxidase staining for S-100 protein and HMB-45. The lesions studied included common acquired nevi, spindle cell and epithelioid cell nevi (Spitz nevi), cellular blue nevi, deep penetrating nevi, congenital nevi, nevi from hormonally reactive areas (genital), malignant melanoma, and desmoplastic malignant melanoma. A positive reaction for HMB-45 was seen in the dermal component in a high percentage of each of these types of lesions except for the common acquired nevi and the desmoplastic malignant melanomas that were uniformly negative for HMB-45 in the dermal component. HMB-45 correlates with melanosome production and thus a melanocytic origin of HMB-45-positive cells. HMB-45 may correlate best with factors that stimulate melanocytic proliferation and production of melanosomes.

Adolescent↗