Nonprescription and alternative medication use by individuals with HIV disease

OBJECTIVE

To examine the strength of the associations between predisposing, enabling, and need-for-care variables and the self-treatment of HIV disease; and to compare sociodemographic and illness-related factors associated with the use of vitamins, nonprescription medications, herbs, and recreational substances among HIV-infected individuals.

METHODS

Data were derived from 7887 interviews conducted as part of the AIDS Cost and Services Utilization Survey. The conceptual framework was the Andersen Behavioral Model of Health Services Use. Factors associated with nonprescription and alternative medication use were assessed using logistic regression. Generalized estimating equations were applied to adjust variance estimates for within-person correlations of drug use over time.

RESULTS

After adjusting for perceived health status, T cell count, and stage of disease, the results indicated that African-Americans were less likely to use nonprescription drugs (odds ratio [OR] 0.65, 95% CI 0.52 to 0.81), vitamins (OR 0.59, 95% CI 0.48 to 0.73), and herbs (OR 0.41, 95% CI 0.22 to 0.76), compared with non-Hispanic whites. Similarly, Hispanics were less likely to report use of herbs (OR 0.58, 95% CI 0.34 to 0.98) or recreational drugs (OR 0.34, 95% CI 0.15 to 0.76) than were non-Hispanic whites. Oppositely, individuals who had a college education were more likely to use vitamins (OR 1.26, 95% CI 1.05 to 1.50) and herbs (OR 2.47, 95% CI 1.56 to 3.91). Enabling variables such as insurance status and income were generally associated only with use of recreational drugs. Need-for-care variables were generally associated only with use of nonprescription drugs and vitamins.

CONCLUSIONS

Predisposing, enabling, and need-for-care variables from the Andersen Behavioral Model were significantly associated with the use of four categories of drugs to self-treat HIV disease. However, there was not a consistent pattern across the drug categories.

Endothelial cells modulate the proliferation of mural cell precursors via platelet-derived growth factor-BB and heterotypic cell contact

Embryological data suggest that endothelial cells (ECs) direct the recruitment and differentiation of mural cell precursors. We have developed in vitro coculture systems to model some of these events and have shown that ECs direct the migration of undifferentiated mesenchymal cells (10T1/2 cells) and induce their differentiation toward a smooth muscle cell/pericyte lineage. The present study was undertaken to investigate cell proliferation in these cocultures. ECs and 10T1/2 cells were cocultured in an underagarose assay in the absence of contact. There was a 2-fold increase in bromodeoxyuridine labeling of 10T1/2 cells in response to ECs, which was completely inhibited by the inclusion of neutralizing antiserum against platelet-derived growth factor (PDGF)-B. Antisera against PDGF-A, basic fibroblast growth factor, or transforming growth factor (TGF)-beta had no effect on EC-stimulated 10T1/2 cell proliferation. EC proliferation was not influenced by coculture with 10T1/2 cells in the absence of contact. The cells were then cocultured so that contact was permitted. Double labeling and fluorescence-activated cell sorter analysis revealed that ECs and 10T1/2 cells were growth-inhibited by 43% and 47%, respectively. Conditioned media from contacting EC-10T1/2 cell cocultures inhibited the growth of both cell types by 61% and 48%, respectively. Although we have previously shown a role for TGF-beta in coculture-induced mural cell differentiation, growth inhibition resulting from contacting cocultures or conditioned media was not suppressed by the presence of neutralizing antiserum against TGF-beta. Furthermore, the decreased proliferation of 10T1/2 cells in the direct cocultures could not be attributed to downregulation of the PDGF-B in ECs or the PDGF receptor-beta in the 10T1/2 cells. Our data suggest that modulation of proliferation occurs during EC recruitment of mesenchymal cells and that heterotypic cell-cell contact and soluble factors play a role in growth control during vessel assembly.

Endogenous mouse interleukin-10 is up-regulated by exogenously administered recombinant human interleukin-10, but does not contribute to the efficacy of the human protein in mouse models of endotoxemia

In murine models of experimental endotoxemia, inflammatory cytokines as well as antiinflammatory interleukin-10 (IL-10) appear in the circulation after the injection of lipopolysaccharide (LPS). There is considerable experimental evidence to suggest that the major function of endogenously produced IL-10 is to down-regulate inflammatory cytokine production. Indeed, the protective effects of exogenously administered IL-10 against murine endotoxin lethality have been shown to correlate with its ability to inhibit the LPS-induced production of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). While mouse IL-10 (mIL-10) has been used in the majority of studies in murine endotoxemia, we have found the human homolog to be equally effective in suppressing inflammatory cytokine production and in protecting mice from endotoxin lethality. However, we have recently observed that the LPS-induced endogenous IL-10 response is enhanced when mice are treated with recombinant human IL-10 (rhuIL-10). The upregulation of endogenous IL-10 by exogenously administered rhuIL-10 is particularly evident in mice that are primed with Corynebacterium partum (Proprionibacterium acnes). In the present study, we have examined the potential contributions of the increased circulating levels of mouse IL-10 to the inhibitory effects seen with rhuIL-10 on inflammatory cytokine production and endotoxin lethality. We show that pretreatment with a neutralizing anti-mouse IL-10 monoclonal antibody (mAb) has no effect on the ability of rhuIL-10 to suppress an LPS-induced inflammatory cytokine response in these mice. In contrast, the suppressive effects of the human protein on inflammatory cytokine responses are blocked completely by pretreating the animals with an anti-huIL-10 mAb. These data show that despite the up-regulated endogenous IL-10 response, it is the exogenously administered rhuIL-10 that is directly responsible for the suppressed inflammatory cytokine responses that are observed when the human protein is given to endotoxemic mice.

Testosterone administration preserves protein balance but not muscle strength during 28 days of bed rest

Decrements in muscle strength as a result of prolonged bed rest are well defined, but little is known about potential countermeasures for preventing loss of strength under this condition. The purpose of this study was to determine whether testosterone administration would preserve protein balance and muscle strength during prolonged bed rest. Ten healthy men (age, 36 +/- 2 yr; height, 177.2 +/- 3.4 cm; weight, 80.5 +/- 3.9 kg; mean +/- SE) were admitted to our in-patient metabolic unit. After a 1-week ambulatory run-in period, each subject was confined to bed for 28 days at 6 degree head-down tilt while receiving a daily oral dose of T3 (50 microg/day). During the bed rest/T3 period, six of the men were randomized to receive testosterone enanthate by i.m. injection (T; 200 mg/week) while four received placebo in a double blind fashion. Nitrogen balance was determined throughout, and whole body [13C]leucine kinetics were assessed at baseline and on day 26 of bed rest. Before bed rest and on the third day of reambulation, the muscle strength of the knee extensors and flexors and shoulder extensors and flexors was determined at 60 degrees/s on a Cybex isokinetic dynamometer. Despite improved [13C]leucine kinetics and maintenance of nitrogen balance and lean body mass in T-treated subjects, little preservation of muscle strength, particularly in the knee extensors, was noted. Muscle strength [reported as the best work repetition in foot-pounds (FtLb)] for right knee extensors declined (P = 0.011) similarly in both groups; from 165 +/- 15 to 126 +/- 18 FtLb in T-treated men and from 179 +/- 22 to 149 +/- 13 FtLb in placebo-treated men. Overall, there was less of a decline in extension and flexion strength of the shoulder compared to the knee, with no benefit from T. These results suggest that in the absence of daily ambulatory activity, T administration will not increase or, in the case of this bed rest model, preserve muscle strength.

Optical testing of condoms

Condoms provide one of the most important means of preventing pregnancy and the spread of human immunodeficiency virus (HIV) and other sexually transmitted diseases. Pinhole defects may lead to the passage of sperm or viruses through the condom wall. Embedded particles, which may become dislodged in handling or use, may represent latent pinhole defects. Thin regions in the condom wall may lead to breakage in use. Testing for such defects in regulatory laboratories, or in the factories as part of production screening or quality assurance efforts, is a major tool for ensuring condom reliability. A new optical method for testing condoms is presented, sensitive to pinholes, thin regions, and embedded particles. The method could supplement or replace the existing, less powerful, electrical test techniques in either regulatory testing laboratories or in the factory. The optical techniques presented provide quantitative data on the condoms tested, rather than just accept/reject decisions. They thus support detailed monitoring of production or lot characteristics that is generally not possible with existing electrical techniques. The ability of the optical techniques to separately test for and identify not only pinholes, but also thin regions and embedded particles, which are not separately tested for with the electrical technologies, is an especially important new capability. Further, the new optical techniques allow the locations of defects found to be precisely marked, making possible a microscopic examination of defects useful in studying their structure and possible causes. The optical technique is also totally nondestructive, in that it does not alter the defects whose structures are of interest. Initial results are reported on the testing of latex condoms purchased in retail stores. Condoms identified optically as being potentially defective were subjected to industry standard leak and burst testing. Results of the various tests are summarized. The data suggest that use of the new optical test techniques could have prevented an unexpectedly large number of condoms with significant pinhole and thin region defects from reaching the public. Optical test systems could be used to support either regulatory, quality assurance, or clinical field testing of latex or nonlatex condoms. Due to their high rate capability and level of automation, they could also be applied to 100% screening testing in the factory. The new test techniques could also be used to detect defects in a wide range of other thin sheets and membranes.

Interleukin-10 dose-dependent regulation of CD4+ and CD8+ T cell-mediated graft-versus-host disease

BACKGROUND

Endogenous interleukin (IL)-10 production has been associated with the lack of graft-versus-host disease (GVHD) in human recipients of MHC-disparate donor grafts. Paradoxically, we have shown that the exogenous administration of high doses (30 microg/dose) of IL-10 to murine recipients of MHC-disparate grafts accelerates GVHD lethality.

METHODS

The effects of IL-10 on GVHD mediated by either CD4+ or CD8+ T cells was examined in studies involving exogenous IL-10 administration or the infusion of T cells from IL-10-deficient (-/-) donor mice. The role of interferon (IFN)-gamma on IL-10-induced GVHD acceleration was studied using IFN-gamma-deficient (-/-) donor mice or neutralizing monoclonal antibody.

RESULTS

IL-10 was found to have a dose-dependent effect on the GVHD lethality mediated by either CD4+ or CD8+ T cells. High doses of exogenous IL-10 accelerated GVHD lethality. IFN-gamma release was not responsible for the IL-10 facilitation of GVHD lethality. Paradoxically, low doses of IL-10 protected mice against GVHD lethality. The GVHD protective effect of the bioavailability of small amounts of IL-10 was confirmed by demonstrating that the infusion of T cells from IL-10 -/- donors accelerated GVHD lethality.

CONCLUSIONS

The results suggest that IL-10 has a dose-dependent effect on the GVHD lethality mediated by CD4+ or CD8+ T cells, such that high doses accelerate lethality, while low amounts of bioavailable IL-10 are protective.

Preliminary evaluation of a simple in vitro test for the diagnosis of type C botulism in wild birds

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of type C botulinum toxin (Clostridium botulinum) in wild birds. This simple, antigen-capture ELISA utilizes polystyrene immunosticks as the solid substrate, chicken antitoxin (IgY) as the coating antibody, rabbit antitoxin as the primary antibody, and peroxidase-labeled goat-anti-rabbit as the secondary antibody. To evaluate the immunostick ELISA as a diagnostic test for avian botulism, known concentrations of toxin were added to heparinized blood collected from healthy birds and tested by both the ELISA and mouse bioassay. Also, blood samples from 236 bird carcasses submitted to the National Wildlife Health Center (NWHC) for cause of death determinations were tested by both procedures. Using < or = 0.5 ml as the test volume for both procedures, the ELISA was less sensitive, detecting 0.25 ng/ml of toxin compared to 0.12 ng/ml for the mouse bioassay. Using the same volume of test sample for diagnostic submissions (< or = 0.5 ml), the ELISA was positive for 60% of the 149 clinically-diagnosed cases of botulism, whereas the mouse bioassay was positive for 79%. However, we demonstrated that with larger sample volumes (> or = 1.0 ml), the sensitivity of the ELISA may be equivalent or better than the mouse test due to the concentrating effect of the ELISA procedure. These preliminary results suggest that when adequate sample volumes are available, the immunostick ELISA can replace the mouse test for the diagnosis of botulism in wild birds.

Carbon monoxide mass exposure in a pediatric population

OBJECTIVES

To describe the outcomes of a mass carbon monoxide (CO) intoxication, and to calculate the CO half-life in a pediatric school-aged population.

METHODS

A retrospective chart review was performed based on Regional Poison Center database information, hospital laboratory data, and medical records of the pediatric patients who sought care at one of 3 St. Louis area hospitals, after exposure to high levels of CO. Exposures occurred on January 5, 1996, after evidence of a CO leak was discovered at an area elementary school. Charts were reviewed for major demographics, symptoms reported, carboxyhemoglobin (COHb) levels and times, and level of effect.

RESULTS

Information about 177 (35%) of the 504 children in attendance at school that day was available. Mean age was 8.7 +/- 1.8 years (range 4-12 years). Symptoms were present in 155 (88%) of the 177 children for whom data were available. Initial COHb levels were obtained for 147 (83.1%) of the 177 children. First mean COHb level was 7.0% (95% CI = 6.6-7.5%). Second COHb level was obtained for 26 children with a mean of 2.7% (95% CI = 2.2-3.2%). Calculated half-life of COHb, on 100% O2 at 1 atm, was 44.0 minutes (95% CI = 39.6-48.2 minutes).

CONCLUSION

Some children had symptoms at COHb levels that traditionally have been considered nontoxic. The elimination of COHb was found to be more rapid in this population of children than reported in other studies.

Effect of undergraduate college major on performance in medical school

PURPOSE

To determine whether choice of college major has any effect on performance in medical school.

METHOD

The author analyzed data for 406 students enrolled in a combined baccalaureate-MD program at Brown University School of Medicine who had matriculated in medical school from 1989 to 1997, determining their undergraduate majors and their medical education performances (as measured by course grades, USMLE, scores and residency program evaluation).

RESULTS

Slightly over half of the students had majored in science or mathematics, about a third had majored in the humanities or social sciences, and about a tenth had had double majors or had been independent concentrators. The author found no statistically significant difference between the medical school performances of students who had majored in the sciences or mathematics and those who had majored in the humanities or the social sciences.

CONCLUSION

Although preselection bias may influence medical school performance, this study affirms previous findings that choice of undergraduate major has little, if any, statistically significant effect.

Identifying and defining the dimensions of community capacity to provide a basis for measurement

Although community capacity is a central concern of community development experts, the concept requires clarification. Because of the potential importance of community capacity to health promotion, the Division of Chronic Disease Control and Community Intervention, Centers for Disease Control and Prevention (CDC), convened a symposium in December 1995 with the hope that a consensus might emerge regarding the dimensions that are integral to community capacity. This article describes the dimensions that the symposium participants suggested as central to the construct, including participation and leadership, skills, resources, social and interorganizational networks, sense of community, understanding of community history, community power, community values, and critical reflection. The dimensions are not exhaustive but may serve as a point of departure to extend and refine the construct and to operationalize ways to assess capacity in communities.

Retention, antimicrobial activity, and clinical outcomes following use of a bioerodible tetracycline gel in moderate-to-deep periodontal pockets

This randomized, examiner masked, split mouth study evaluated a new model to test periodontal therapy involving a novel bioerodible copolymer gel containing tetracycline hydrochloride. Responses to the tetracycline gel and untreated control were compared for product tolerance and 3 different measures of effectiveness (drug retention, changes in microbial levels, and clinical status). The test gel was administered by syringe into the periodontal pockets of 18 systemically healthy adult volunteers, each of whom presented with 3 or more sites with 6 mm probing depths. Gingival crevicular fluid samples were used to monitor daily drug levels over 7 days, while clinical responses were assessed at day 30. Overall, the test gel was well-tolerated by all patients. For the 3 effectiveness measures, tetracycline was released throughout the observation period and mean levels exceeded 100 microg/mL over 6 days, statistically significant reductions in selected periodontal pathogens were evident at day 7 but not at day 30, and mean probing depth reductions at test sites were 1.12 mm at 30 days versus 0.36 mm at untreated control sites (P=0.012). The safety profile, longer-term drug retention, antimicrobial activity, and clinical response in this Phase I study suggest that this tetracycline-containing copolymer gel platform may represent a safe and effective bioerodible therapy for periodontitis. The experimental model also shows merit for early phase clinical testing of novel therapeutic agents.

Tumescent anesthesia in ambulatory phlebectomy

BACKGROUND

Ambulatory phlebectomy is an elegant outpatient procedure for the removal of varicose veins. One of the keys to its success is the ability to perform the procedure under local anesthesia. A new form of anesthesia, tumescent anesthesia, has been developed for liposuction surgery and is now being expanded for use in other surgical disciplines.

OBJECTIVE

To determine the efficacy and safety as well as review the use and advantages of tumescent anesthesia in ambulatory phlebectomy.

METHODS

A retrospective review of phlebectomy cases performed in our offices under tumescent anesthesia.

RESULTS

The reported level of intraoperative and postoperative pain was very low. The complication rate was consistent with other reports except for a higher number of hematomas (3.4%).

CONCLUSIONS

Tumescent anesthesia provides a very safe, comfortable method of anesthetizing patients for ambulatory phlebectomy. Epinephrine, in appropriate concentrations, should be a part of all tumescent anesthetic solutions used for phlebectomy as it may decrease the incidence of hematoma.

Reliability and validity of a macronutrient self-selection paradigm and a food preference questionnaire

Our laboratory has developed a macronutrient self-selection paradigm (MSSP) designed to vary fat content significantly and systematically with sugar, complex carbohydrates, and protein content in a battery of foods in which fat is commonly consumed in the American diet. We have also developed a food preference questionnaire (FPQ) according to an identical design but using a list of foods mutually exclusive of those presented for selection and intake in the MSSP. Men were tested twice on both instruments, with a 4-week interval between tests. It was determined that the MSSP has strong test-retest reliability for overall fat (r = 0.91) and other macronutrient intake and total caloric intake. In addition, hunger and fullness ratings were reproducible, and fat preferences (r = 0.99) and hedonic responses to foods listed on the FPQ were highly consistent across trials. This study also demonstrated that the MSSP is a valid instrument with respect to the men's reports of habitual intake of fat (r = 0.80) and total carbohydrates on the Block food questionnaire (FQ). In addition, men's fat preferences on the FPQ were validated with respect to overall fat (r = 0.86) and total caloric intake in the MSSP and fat intake (r = 0.83) reported on the Block FQ. The MSSP also has the capability to detect a wide range of fat intake (3.06-50.35% among the present subjects), indicating that this instrument can identify individuals who differ markedly in fat intake or could detect changes in fat preference within subjects. In addition, this paradigm detected a large range of sugar and total caloric intake. It is anticipated that the use of these laboratory tools can enhance our understanding of the relationship between dietary fat intake and obesity.

A leptin dose-response study in obese (ob/ob) and lean (+/?) mice

This experiment determined the amount of leptin required to correct different abnormalities in leptin-deficient ob/ob mice. Baseline food intakes and body weights of lean (+/?) and obese (ob/ob) C57B1/6J <ob> mice were recorded for 7 days. An Alzet miniosmotic pump was placed in the peritoneal cavity of each mouse and delivered 0, 1, 2, 5, 10, or 42 microg/day human leptin for 7 days. In ob/ob mice, 2 microg leptin/day reduced food intake and body weight, and increased hypothalamic and brain stem serotonin concentrations. All fat pads were reduced 35-40% by 10 microg leptin/day, and liver weight, lipid, and glycogen decreased. Serum insulin and glucose were reduced in all leptin-treated ob/ob mice, and levels were normalized by 10 microg/day leptin. Low rectal temperatures of ob/ob mice were corrected by 10 and 42 microg/day leptin. These doses also increased brown adipose tissue uncoupling protein expression. The only responses in lean mice were a transient reduction in food intake and weight loss with 10 or 42 microg/day leptin. This study shows enhanced leptin sensitivity in ob/ob mice and suggests that increased temperature and sympathetic activity are indirect responses to high concentrations of protein.

Effects of experimentally induced mild hyperthyroidism on growth hormone and insulin secretion and sex steroid levels in healthy young men

Although triiodothyronine (T3) exerts major regulatory actions in both animals and humans, most clinical studies of T3 administration have been relatively short-term. The present study examined the effects of more than 2 months (63 days) of low-dose T3 treatment on overnight pulsatile growth hormone (GH) secretion, short-term insulin secretion, and of sex steroid levels in seven healthy, lean men studied at an inpatient metabolic unit. At baseline, there were strong correlations between sex hormone-binding globulin (SHBG) and several measures of GH production, including total GH production (r = .99), GH interburst interval (r = -.75), and GH mass (r = .82). SHBG was also inversely correlated with basal insulin secretion (r = -.74). There was a 42% increase in serum levels of total testosterone (18.5 +/- 1.3 to 26.3 +/- 1.8 nmol/L, P = .005) and a 150% increase in SHBG (18.0 +/- 2.2 to 44.9 +/- 7.0 nmol/L, P = .008) following T3 treatment. Estradiol and free testosterone levels were unchanged by treatment, although free testosterone decreased from 142.8 +/- 18.4 to 137.3 +/- 19.5 pmol/L. T3 treatment significantly reduced the GH interburst interval (P < .05) and produced slight increases in the measures of GH secretion. There were no statistically significant effects of T3 treatment on insulin secretion, although insulin peak amplitude, mass secreted per burst, and total production all decreased. We conclude that experimentally induced T3 excess in healthy men produces significant and sustained changes in sex hormone levels and GH secretion. Furthermore, there are strong associations between SHBG and both GH and insulin secretion independent of thyroid hormone excess that require additional study.

Development and validation of a measure of adolescent dissociation: the Adolescent Dissociative Experiences Scale

This study describes the initial reliability and validity data on the Adolescent Dissociative Experiences Scale (A-DES), a screening measure for pathological dissociation during adolescence. The A-DES showed good scale and subscale reliability, and, as hypothesized, increased scores were associated with reported trauma in a patient population. A-DES scores were able to distinguish dissociative disordered adolescents from a normal sample and from a patient sample with a variety of diagnoses.

Soluble IL-6R in plasma cell dyscrasias

The understanding of the biology of multiple myeloma has advanced significantly in the past few years. The identification of the pivotal role of Interleukin-6 (IL-6), the soluble IL-6 receptor (sIL-6R), and how the ligand receptor complex interacts with the signal transducer gp130 has provided new biological insights into plasma cell disorders. Some studies have suggested that sIL-6R levels may have prognostic significance in MM, however this is not a consistent finding. Here the biology and function of IL-6 and sIL-6R are reviewed and the clinical significance of sIL-6R discussed.

Voluntary wheel running decreases adipose tissue mass and expression of leptin mRNA in Osborne-Mendel rats

The purpose of this study was to assess the effects of voluntary wheel running on the expression of leptin mRNA in rats that are either sensitive (OM) or resistant (S5B/Pl) to diet-induced obesity. Male OM and S5B/Pl rats had ad libitum access to standard rodent diet and water. At 3-5 weeks of age, animals of both strains were randomly assigned to either an exercise or sedentary control group. The exercise groups had 24-h access to a running wheel, and they trained for 7 weeks. During weeks 1-4, animals in both OM and S5B/Pl exercise groups progressively increased their running. During weeks 5-7, S5B/Pl exercisers tended to run more than did OM (approximately 60 vs. 45 km/week), but by the end of the study both groups had an equally greater heart weight (mg/g body weight) and planteris citrate synthase activity than their sedentary controls. Oral glucose tolerance tests performed during the last week of training revealed that compared with their appropriate controls, insulin sensitivity was enhanced (P < 0.05) in OM but not in the S5B/Pl wheel-running groups. Inguinal, epididymal, and retroperitoneal fat pads weighed less in the running than in the nonrunning groups of both strains (P < 0.01). Additionally, exercised animals had an increased percentage of smaller cells (40-60 microm; P < 0.05) and a decreased percentage of larger cells (120-160 microm; P < 0.05) in the epididymal fat depot. Epididymal leptin mRNA measured by Northern blot analysis was reduced in the exercise-trained rats of both strains (P < 0.05). Furthermore, serum leptin was reduced in exercise-trained compared with the control animals of both strains. In comparison to S5B/Pl, control OM animals exhibited both a higher expression and higher circulating levels of leptin (P < 0.05). While serum leptin levels were decreased and food intake was increased in the exercise-trained animals of both strains (P < 0.05), the exact relationship between exercise, leptin, and food intake in this rat model of dietary obesity remains to be determined. Nonetheless, these results suggest that the expression and secretion of leptin can be influenced by exercise training and that these changes (i.e., reduced expression and secretion of protein) can occur independently of changes in whole-body insulin sensitivity and susceptibility to diet-induced obesity.

Infections complicating pulsed carbon dioxide laser resurfacing for photoaged facial skin

BACKGROUND

With proper technique and instrumentation, laser resurfacing for facial wrinkles has been found to be highly effective and relatively safe. Most, if not all, of the noninfectious complications such as pigmentary changes, scarring, and persistent erythema can either be avoided or managed with appropriate therapy. Postoperative infections, on the other hand, may develop despite proper technique and instrumentation. Without proper management, they may cause significant physical morbidity and psychological distress defying the expected benefit of the procedure.

OBJECTIVE

To quantify the incidence and to study the characteristics of infections arising after laser resurfacing for facial wrinkles with pulsed carbon dioxide laser treatment.

METHOD

A retrospective study was carried out by reviewing the records of all patients undergoing laser resurfacing for facial wrinkles from January 1, 1995 to April 30, 1996. An infection is defined as a positive culture in the presence of signs or symptoms of an infection.

RESULTS

Over 16 months, 395 procedures were performed and 17 cases of culture-proven infection recorded, an incidence of 4.3%. All patients had symptoms starting between days 2 and 10 after the operation. Over half of the patients had multiple infections with two to three microorganisms. Pseudomonas aeruginosa was the most common causative agent, found in 41% of all infected cases, followed by Staphylococcus aureus (35%), S. epidermidis (35%), and Candida species (24%). Multiple drug-resistant, gram-negative bacteria were found in four cases, implicating the possibility of hospital-acquired infections. Almost all isolates of gram-positive bacteria were resistant to both erythromycin and penicillin, but not oxacillin. With proper treatment, most patients healed normally. Only one patient had persistent, multiple atrophic scars due to locally disseminated herpes simplex infection despite proper prophylaxis and treatment.

CONCLUSIONS

Postoperative infection is uncommon and manageable with early recognition and proper treatment. The types of infectious agents being found are very similar to those reported in burn patients. This complication has been found to be much more common in patients undergoing full face resurfacing and those using a bio-occlusive dressing postoperatively. With comprehensive preventive and management measures, it is likely that this type of uncommon, yet distressful, complication can be avoided and more successfully treated. Recommendations are made for prevention and management of suspected postoperative infections.