Flemish network on rare connective tissue diseases (CTD): patient pathways in systemic sclerosis. First steps taken

Despite the low prevalence of each rare disease, the total burden is high. Patients with rare diseases encounter numerous barriers, including delayed diagnosis and limited access to high-quality treatments. In order to tackle these challenges, the European Commission launched the European Reference Networks (ERNs), cross-border networks of healthcare providers and patients representatives. In parallel, the aims and structure of these ERNs were translated at the federal and regional levels, resulting in the creation of the Flemish Network of Rare Diseases. In line with the mission of the ERNs and to ensure equal access to care, we describe as first patient pathways for systemic sclerosis (SSc), as a pilot model for other rare connective and musculoskeletal diseases. Consensus was reached on following key messages: 1. Patients with SSc should have multidisciplinary clinical and investigational evaluations in a tertiary reference expert centre at baseline, and subsequently every three to 5 years. Intermediately, a yearly clinical evaluation should be provided in the reference centre, whilst SSc technical evaluations are permissionably executed in a centre that follows SSc-specific clinical practice guidelines. In between, monitoring can take place in secondary care units, under the condition that qualitative examinations and care including interactive multidisciplinary consultations can be provided. 2. Patients with early diffuse cutaneous SSc, (progressive) interstitial lung disease and/or pulmonary arterial hypertension should undergo regular evaluations in specialised tertiary care reference institutions. 3. Monitoring of patients with progressive interstitial lung disease and/or pulmonary (arterial) hypertension will be done in agreement with experts of ERN LUNG.

Abstract P5-16-14: Outcome of lipofilling in patients with a history of breast cancer: A retrospective cohort study

Background:Autologous fat grafting [AFG] is a surgical technique used to correct breast deformities or to reconstruct partial breast deformities after breast conservative treatment [BCT] or mastectomy for breast cancer. However, a strong debate remains upon the topic of safety and the oncological risk after lipofilling. There is a need for more studies assigned with a higher level of evidence.

Objective:This retrospective cohort study aimed to provide a strong evidence-based argument concerning the safety of fat grafting in patients who underwent breast cancer surgery in comparison to a group with similar characteristics who did not receive lipofilling.

Methods: Two cohorts consisting of women with a history of breast cancer were retrospectively assembled. All patients underwent BCT and/or a mastectomy as breast cancer treatment. An intervention population of patients that had received primary or secondary lipofilling was statistically compared to a control population of patients that had received a breast reconstruction without lipofilling.

Results: Fifty patients with a mean age of 53.6 ± 9.3 years at the time of lipofilling were included in the intervention cohort. The control group included 67 patients with a mean age of 52.8 ± 8.5 years at the time of breast reconstruction. Both cohorts showed no significant differences for demographic or oncological data. Mean follow-up time was 15.0 ± 15.6 months in the intervention group and 45.4 ± 35.1 months in the control group. The prevalence of the complications are shown in the table. No complications were seen in 35 patients [70%] after lipofilling. Fat necrosis was mostly observed [n=15] but no infections or local oncological recurrences were reported. In the control group a complication-free follow-up occurred in 38 patients [56.7%] after breast reconstruction. One control patient demonstrated a local oncological recurrence. A higher prevalence of infections was observed in the control population [p = 0.048] and the prevalence of fat necrosis was higher after lipofilling [p = 0.028].

Prevalence of complications Study populationStudy populationControl populationControl populationp-valueLocal oncological recurrence0 1(1.5%)0.386Infection0 5(7.5%)0.048Fet necrosis15(30.0%)9(13.4%)0.028Microcalcifications3(6.0%)3(4.5%)0.712Other1(2.0%)17(25.4%)0.086- hematoma1(2.0%)5(7.5%) - seroma0 2(3.0%) - capsular contracture0 1(1.5%) -implant leak0 1(1.5%) - implant/flap loss0 6(9.0%) - implant redo0 1(1.5%) - rash0 1(1.5%) None35(70%)38(56.7%)0.142

Conclusion: Lipofilling is a safe technique for breast reconstruction in patients with a history of breast cancer. There is no increase in local oncological recurrence. A side effect is an increase in fat necrosis which can potentially lead to more investigations.

Citation Format: Thiessen F, De Schrijver L, De Decker M, Tondu T, Van Goethem M, Tjalma WA. Outcome of lipofilling in patients with a history of breast cancer: A retrospective cohort study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-16-14.

Breast cancer and fat grafting: efficacy, safety and complications-a systematic review

Autologous fat grafting (AFG) or lipofilling is nowadays a popular technique for breast reconstruction after breast cancer surgery. There is debate regarding the oncological safety and risks of this procedure in breast cancer patients. A systematic review of the literature published between January first 1995 and October first 2016 was conducted regarding the efficacy, safety and complications of this technique in breast cancer patients after their cancer treatment. The databases PubMed, Science Direct and Thomson Reuters Web of Science were used to search for qualified articles. Inclusion criteria were women with a personal history of breast cancer and at least one lipofilling procedure. Only studies containing a minimum of 20 patients were included in this systematic review. The search yielded a total of 23 suitable articles: 18 case series, 4 retrospective cohort studies and one prospective cohort study. The systematic review encompassed a total of 2419 patients. Medical imaging was used in the majority of the studies to assess the follow-up. Mammography was the most popular technique (65.2%), followed by ultrasound (47.8%) and MRI (30.4%). The prevalence of complications was the following: fat necrosis in 5.31%, benign lesions, like cysts or calcifications in 8.78%, infections in 0.96% and local cancer recurrence in 1.69%. AFG or lipofilling appears to be an oncological safe technique with a low morbidity in women with a history of breast cancer. In order to have a better understanding and evidence of the oncological safety a randomised controlled trial is urgently needed. We further recommend that all AFG be registered in the cancer register.

Effect of the cathepsin K inhibitor odanacatib on bone resorption biomarkers in healthy postmenopausal women: two double-blind, randomized, placebo-controlled phase I studies

Inhibition of cathepsin K (CatK) is a potential new treatment for osteoporosis. In two double-blind, randomized, placebo-controlled phase I studies, postmenopausal female subjects received odanacatib (ODN), an orally active, potent, and selective CatK inhibitor, once weekly for 3 weeks or once daily for 21 days. Bone turnover biomarkers, safety monitoring, and plasma ODN concentrations were assessed. These studies showed ODN to be well tolerated. Pharmacokinetic (PK) analysis revealed a long half-life (t(1/2); 66-93 h) consistent with once-weekly dosing. Pronounced reductions in C-terminal telopeptide of type I collagen (approximately 62%) and N-terminal telopeptide of type I collagen normalized to creatinine (NTx/Cr) (approximately 62%) at trough (C(168 h)) were seen following weekly administration. Robust reductions in CTx (up to 81%) and NTx/Cr (up to 81%) were seen following daily administration. ODN exhibits robust and sustained suppression of bone resorption biomarkers (CTx and NTx/Cr) at weekly doses > or = 25 mg and daily doses > or = 2.5 mg.

Combination vaccines

The biotechnology revolution has stimulated vaccine development, blessing us with new, safe, and effective vaccines, but burdening our vaccination schedule. The incorporation of multiple individual vaccines into combination vaccines can simplify vaccine administration programs and permit the inclusion of new antigens in the vaccine schedule. Although the development, evaluation, and implementation of combination vaccines pose numerous challenges and raise controversies that remain unresolved, there is a reasonable prospect of United States licensure within the next few years of several new combination vaccines for infant use. Approval in the United States of combination vaccines in use elsewhere might be speeded by improved vaccination tracking systems and post marketing efficacy surveillance, which would provide confidence that material reductions in efficacy could be detected following licensure, and thereby ease concerns regarding moderate, but perhaps immaterial, declines in immunogenicity seen with some combinations.

Principles of pediatric combination vaccines and practical issues related to use in clinical practice

BACKGROUND

During the past two decades the number of injections that are required per office visit to fulfill the recommended childhood immunization schedule has increased dramatically.

METHODS

By reviewing the literature, the principles associated with pediatric combination vaccines are discussed, and practical issues related to their use in clinical practice are evaluated.

RESULTS

The ideal combination vaccine is safe, effective and easy to store and use, and its antigenic components fit within the recommended immunization schedule. The ideal combination is associated with fewer adverse reactions than the separately administered antigens, with improved efficacy and higher immune responses compared with its component vaccines. An acceptable combination vaccine must provide comparable efficacy and safety to its component vaccines. Although there are a limited number of combination vaccines already available [diphtheria-tetanus-pertussis, inactivated poliovirus vaccine (IPV) and measles-mumps-rubella], effort is being focused on combining these vaccines with other routine vaccines of infancy including Haemophilus influenzae type b (Hib) and hepatitis B vaccine (HepB). Currently under review by the Food and Drug Administration are diphtheria-tetanus-acellular pertussis (DTPa)-HepB-IPV and DTPa-Hib-IPV combination vaccines, and two DTPa-HepB-IPV-Hib vaccines have been licensed in Europe. As more combination vaccines become available, issues such as interchangeability and administration of extra doses are raised; however, it is important not to miss a vaccination opportunity.

CONCLUSIONS

The number of injections required to fulfill the recommended childhood immunization schedule at each visit creates problems for patients and practitioner, sometimes risking a missed opportunity for vaccination. The development of combination vaccines will circumvent this problem and increase compliance and vaccination coverage rates.

Combination vaccines

The past decade has shown a marked increase in the number of vaccines currently licensed and recommended for use in infants and children. Although most agree that it is desirable to combine as many of these vaccines as possible into a single injection, safety and efficacy must not be sacrificed. Clearly, a resurgence in Hib meningitis or measles (for example) would not be an acceptable price for the convenience of a single injection; but it is not clear how large a reduction in immunogenicity can be incurred without paying such a price. This conundrum has slowed the licensure of useful combination vaccines, despite a consensus that parents and practitioners have reached a limit to the number of injections they will deliver to young children. We anticipate US licensure for infant use of (at least) one DTaP-IPV-Hib vaccine and one DTaP-IPV-HB vaccine within the next few years, given the apparent lack of material reduction in immunogenicity of these specific combination products. Licensure in the United States of some of the other combinations now used in Europe is also possible, given supporting national surveillance data or improvements in our understanding of the correlates of immunity. Enhanced vaccination tracking systems and postmarketing efficacy surveillance should provide confidence that material reductions in efficacy could be detected following licensure, and thereby ease the approval of combinations that result in moderate, but perhaps immaterial, declines in immunogenicity.

A randomized, double-blinded study of remifentanil versus fentanyl for tonsillectomy and adenoidectomy surgery in pediatric ambulatory surgical patients

We compared, in a double-blinded manner, the anesthetic maintenance and recovery properties of remifentanil with a clinically comparable fentanyl-based anesthetic technique in pediatric ambulatory surgical patients. Anesthesia was induced with either halothane or sevoflurane and nitrous oxide and oxygen. Patients were randomized (computer generated) to receive either remifentanil or fentanyl in a blinded syringe with nitrous oxide and oxygen in one of four possibilities: halothane/remifentanil, halothane/fentanyl, sevoflurane/remifentanil or sevoflurane/fentanyl. In patients receiving remifentanil, a placebo bolus was administered, and a continuous infusion (0.25 microg. kg(-1). min(-1)) was begun. In patients receiving fentanyl, a bolus (2 microg/kg) was administered followed by a placebo continuous infusion. The time from discontinuation of the anesthetic to extubation, discharge from the postanesthesia care unit (PACU), and discharge to home, as well as pain scores, were assessed by a blinded nurse observer. Systolic blood pressure and heart rate were noted at selected times, and adverse events were recorded. Remifentanil provided faster extubation times and higher pain-discomfort scores. PACU and hospital discharge times were similar. There were no statistical differences among the groups for adverse events. There were statistically, but not clinically, significant differences in hemodynamic variables. We noted that continuous infusions of remifentanil were intraoperatively as effective as bolus fentanyl. Although patients could be tracheally extubated earlier with remifentanil, this did not translate to earlier PACU or hospital discharge times. In addition, remifentanil was associated with higher postoperative pain scores. The frequent incidence of postoperative pain observed in the postoperative recovery room suggests that better intraoperative prophylactic analgesic regimens for postoperative pain control are necessary to optimize remifentanil's use as an anesthetic for children.

IMPLICATIONS

This is a study designed to examine the efficacy and safety of a short-acting opioid, remifentanil, when used in pediatric patients. The frequent incidence of postoperative pain observed in the postoperative recovery room suggests that better intraoperative prophylactic analgesic regimens for postoperative pain control are necessary to optimize remifentanil's use as an anesthetic for children.

Acellular pertussis vaccines

Although whole-cell pertussis vaccines have been highly effective in preventing whooping cough, their common and burdensome adverse reactions have spurred the development of safer alternatives. Seven acellular vaccines are licensed in one or more countries; four have been licensed thus far in the United States, and more may follow. Although the licensed acellular pertussis vaccines differ in their immunogenicity, adverse reactions, and efficacy, all are effective and, compared with whole-cell vaccine, are associated with markedly fewer and milder adverse reactions.

An acellular pertussis vaccine in healthy adults: safety and immunogenicity. Pennridge Pediatric Associates

Recent data indicate that Bordetella pertussis can be an important cause of illness in adolescents and adults. In a randomized observer- and subject-blinded study, adults (> or = 18 years of age) received an acellular pertussis (aP) vaccine containing genetically inactivated pertussis toxin (PT), filamentous hemagglutinin (FHA) and pertactin (PRN), or a saline placebo, and were monitored for safety and immunogenicity. IgG antibodies to PT, FHA, and PRN were measured by enzyme-linked immunosorbent assay (ELISA) and PT neutralization by a Chinese hamster ovary (CHO) cell assay. Local reactions, more common in the aP group, were mild and transient. One month after immunization, geometric mean ELISA antibody concentrations for the aP and placebo groups, respectively, were: anti-PT, 463 and 7.6; anti-FHA, 417 and 18; and anti-PRN, 855 and 14. The anti-PT neutralization titers for the aP and placebo groups were 1:3439 and 1:58 respectively. This aP vaccine is a safe and immunogenic candidate booster vaccine against pertussis for adults.

A randomized clinical trial of acellular pertussis vaccines in healthy adults: dose-response comparisons of 5 vaccines and implications for booster immunization

The safety and immunogenicity of 5 acellular pertussis vaccines (ACVs) were compared in a multicenter, randomized, double-blind trial. A total of 481 healthy adults were given a single intramuscular booster dose of ACV or placebo. Three different dose levels were tested for 4 ACVs: full strength (the dose level proposed for infant immunization), one-third strength, and one-tenth strength. For 1 multicomponent vaccine, only the pertussis toxoid dose level varied. Minor injection site reactions were common and similar in frequency among vaccinated groups. Late-onset injection site reactions were seen in all ACV groups. Dose-related increases in mean antibody titers against vaccine antigens were seen after immunization with all ACVs. Antibody responses against antigens not known to be present in the vaccines were detected after immunization with 4/5 ACVs. Antibody levels fell significantly during the year after immunization. These data support evaluation of ACVs for broader use among adolescents and adults.

Incidence of pertussis infection in healthcare workers

OBJECTIVE

To determine the incidence of pertussis infection in two groups of healthcare workers.

DESIGN

Retrospective cohort study.

SETTING

660-bed, urban, tertiary-care university hospital.

PARTICIPANTS

106 resident physicians and 39 emergency department employees.

INTERVENTIONS

Antibodies to pertussis toxin and filamentous hemagglutinin were determined in fresh serum specimens and in stored sera collected 1 to 3 years previously. A 50% rise in both the pertussis toxin and filamentous hemagglutinin from the initial to the follow-up specimen was considered diagnostic of a pertussis infection.

RESULTS

Two of 106 residents had serological evidence of a pertussis infection during 151.3 subject-observation years, for an annual incidence rate of 1.3% (95% confidence interval [CI95], 0%-3.5%). Three of 39 emergency department employees had serological evidence of a pertussis infection during 81.2 subject-observation years, for an annual incidence of 3.6% (CI95, 0%-9.6%). Of these 5 subjects, 2 had symptomatic disease.

CONCLUSION

We found both symptomatic and asymptomatic pertussis infections in two cohorts of healthcare workers. Although the incidence rates were somewhat lower than found in other studies, they nonetheless were higher than for almost all other diseases for which we vaccinate healthcare workers. Our results would support the use of acellular pertussis vaccine in healthcare workers.

Haemophilus influenzae type b vaccines: history, choice and comparisons

The conjugate Haemophilus influenzae type b (Hib) vaccines are safe and far more immunogenic among infants and young children than is the unconjugated H. influenzae type b polysaccharide. The vaccines differ in their immunogenicity when used for primary immunization of infants, and these differences appear to be predictive of efficacy, such that some vaccines might be more suitable than others in certain populations.

International variation in the management of infants hospitalized with respiratory syncytial virus. International RSV Study Group

Respiratory syncytial virus (RSV) is a frequent cause of hospitalization among infants. To compare patient management in Europe, the United States, and Australia, we analyzed the charts of 1,563 pediatric patients hospitalized with laboratory-confirmed RSV lower respiratory infections during recent RSV seasons. Half of patients had been seen initially as outpatients. Median duration of hospitalization was 4 days in Australia, Finland, the United Kingdom, and the United States, and 8 or 9 days in Belgium, France, Germany, Italy, and the Netherlands. In a linear regression model that included clinical findings, underlying conditions, prematurity, and age, the leading variable associated with length of stay was "hospitalization in continental Europe". This geographic factor conferred a 1.8-fold longer stay (95% CI: 1.7-1.9) than hospitalization elsewhere. Utilization of nine supportive therapies for RSV varied widely among hospitals, even within the same country. The individual hospital was strongly associated with the use of every therapy studied, independent of patient characteristics and clinical status.

CONCLUSION

Management of RSV patients varies markedly by country and hospital. Multicenter RSV trials that measure length of stay should standardize criteria for "readiness for discharge". It may be appropriate to limit international trials to countries with similar median stays for RSV. Variability within multicenter trials could be further controlled by standardizing the use of other therapies and the diagnosis of complications.

A safety and immunogenicity comparison of 12 acellular pertussis vaccines and one whole-cell pertussis vaccine given as a fourth dose in 15- to 20-month-old children

OBJECTIVE

To compare the safety and immunogenicity of 12 different acellular pertussis vaccines combined with diphtheria and tetanus toxoids (DTaP) with one licensed diphtheria, tetanus, and whole-cell pertussis vaccine (DTwP) as a fourth-dose booster in children who had previously received DTaP or DTwP primary vaccinations.

METHODS

Healthy 15- to 20-month-old children were enrolled at six National Institutes of Health Vaccine Treatment and Evaluation Units. All had been randomly assigned to receive three primary doses of DTaP or DTwP at 2, 4, and 6 months of age as part of an earlier National Institutes of Health multicenter trial of DTaP vaccines in the same Vaccine Treatment and Evaluation Units. Parents recorded the occurrence and magnitude of fever; irritability; and injection site redness, swelling, and pain for 3 days after vaccination. Sera obtained before and 1 month after the booster vaccination were analyzed for antibody to pertussis toxin (PT), filamentous hemagglutinin (FHA), fimbriae (FIM), and pertactin (PRN). Diphtheria and tetanus toxoid as well as PT neutralizing (Chinese hamster ovary cell) and whole-cell agglutinating antibodies were measured on a subset of sera.

RESULTS

A total of 1293 children contributed fourth-dose reaction data. Reactions were less frequent after DTaP than after DTwP. For children vaccinated with a fourth dose of DTaP, which was the same DTaP as received in the primary series, fever and injection site redness, swelling, and pain increased in prevalence compared with the third dose in the primary series. For children receiving DTaP as a fourth dose, injection site redness and swelling occurred more frequently in DTaP-primed than in DTwP-primed children. Variation in the occurrence of reactions among DTaP vaccines was observed. A total of 1160 paired pre- and postvaccination sera were available for analysis. Serum antibody concentrations before boosting were lower than those obtained 1 month after the primary immunization. After the fourth dose, significant increases in antibodies directed against the included antigens were observed for all vaccines; postbooster vaccination antibody titers differed significantly among the DTaP vaccines. For children primed and boosted with the same DTaP, antibody levels were not directly related to the quantity of antigen included for PT, FHA, and FIM; for PRN, there was a closer relationship. Some DTaP vaccines given as fourth-dose boosters elicited antibody to PRN or FIM in some vaccinees, although the DTaP vaccines were not reported to contain these antigens; these responses were observed more frequently in DTwP-primed children. Agglutinin antibody rises were observed in all groups immunized with four doses of a DTaP vaccine containing FHA or PRN, regardless of whether the vaccine included FIM. Diphtheria and tetanus antibody levels exceeded the presumed protective concentration (0.1 IU/mL for diphtheria and 0.01 IU/mL for tetanus) after the fourth dose for all vaccinees.

CONCLUSION

Although differences were observed in reaction rates among the DTaP vaccines given as a fourth dose, the DTaP vaccines were, in general, associated with fewer adverse events than a US-licensed DTwP. For DTaP vaccines, fever; irritability; and injection site pain, redness, and swelling occurred more frequently after the fourth dose than after the third dose of the same vaccine in the primary series. No DTaP was consistently most or least reactogenic or immunogenic. Although serologic correlates of pertussis immunity are not defined, it is clear that most DTaP vaccines can stimulate comparable or higher serum antibody responses than DTwP for those antigens contained in the vaccine.

Combination vaccines consisting of acellular pertussis vaccines

Combination vaccines consisting of multiple vaccine antigens delivered in a single injection simplify vaccine administration. Combining multiple antigens into one injection, however, presupposes that the administration of multiple vaccines in combination will not reduce the safety and immunogenicity of the component vaccines. New generation vaccines seek to combine many more antigens from multiple, different pathogens, making them difficult to study in controlled, double blind, randomized clinical trials because of the number of study arms required for complete evaluation. Methods to simplify studies of combination vaccines include building on the framework of earlier studies to calculate sample size and reduce the number of control arms, standardizing serologic assays and assessment of adverse reactions and determining serologic correlates of protection to minimize the need for multiple efficacy studies and to facilitate evaluation of immunogenicity studies. Preliminary data indicate that immune responses to combination vaccines including diphtheria-tetanus-acellular pertussis, hepatitis B and inactivated poliovirus are comparable with those seen when the vaccines are administered separately. In contrast studies of combination vaccines that include Haemophilus influenzae type b Hib antigens show a diminished Hib antibody response, although the clinical relevance of this lowered antibody response has not yet been determined. Numerous small safety studies of combined vaccines have not found evidence of increased adverse reactions.

Prevalence of positive serology for acute Chlamydia pneumoniae infection in emergency department patients with persistent cough

OBJECTIVE

To determine the prevalence of acute Chlamydia pneumoniae infection in ED patients presenting with a persistent cough.

METHODS

This was a case series consisting of a convenience sample of 65 patients > or = 18 years of age who presented with a chief complaint of a cough lasting > or = 2 weeks. Patients were treated in the ED of an urban university hospital. Patients with immunosuppression, lung disease, pneumonia, or a cough lasting > or = 3 months were excluded. Acute and convalescent sera were assayed for antibody to C. pneumoniae. Subjects with C. pneumoniae antibody titers showing a fourfold rise in either immunoglobin M (IgM) or immunoglobin G (IgG) antibody, an IgM titer of > or = 16, or an IgG titer of > or = 512 were considered to have evidence of acute C. pneumoniae infection.

RESULTS

Thirteen (20%; 95% CI, 11% to 32%) of the 65 subjects had serologic evidence of acute C. pneumoniae infection. Except for an increased rate of fever, clinical signs and symptoms and laboratory studies did not differentiate those who had C. pneumoniae from those who did not have the disease. Patients diagnosed as having Bordetella pertussis or Mycoplasma pneumoniae infection did not have serologic evidence of concurrent C. pneumoniae infection.

CONCLUSIONS

C. pneumoniae infection appears to be associated with a persistent cough in ED patients. Clinicians should consider this organism when evaluating these patients. It is unclear whether antibiotic therapy is indicated for these patients. If antibiotics are used, a tetracycline or macrolide antibiotic would be most appropriate.

Comparison of serological results in the NIAID Multicenter Acellular Pertussis Trial with recent efficacy trials

Comparison of the serological results from the NIAID-funded Multicenter Acellular Pertussis Trial (MAPT) and the efficacy trials are complicated by differences in assay methods, immunization schedules, vaccine lots and populations immunized. In spite of these differences, serological results closely approximating those obtained in the MAPT were found for most or all of the assayed antibodies in the Mainz and Erlangen studies. Serological results for some of the antigens included in the vaccines used in the Italian and Stockholm trials were similar to the MAPT results, while significant differences were noted with other antigens. Differences in immunization schedules and serological assay methods made comparisons between MAPT and the Gothenburg and Senegal trials more difficult. Our understanding of the efficacy trial results, and our ability to apply those results to the U.S. population, would be enhanced markedly by simultaneous re-analysis of stored sera from MAPT and selected efficacy trials. This goal should be given priority by the study organizers and sponsors.

The multicenter acellular pertussis trial: an overview

A multicenter, randomized, double-blind study was undertaken in 2342 infants to evaluate the safety and immunogenicity of 13 acellular and 2 whole cell pertussis vaccines combined with diphtheria and tetanus toxoids. Vaccines were administered to infants at 2, 4, and 6 months of age. Sera were obtained before the first vaccination (age 2 months) and 1 month after the third vaccination (age 7 months). All of the acellular vaccines produced significant increases in antibody for included antigens; mean antibody levels often exceeded those obtained with the reference whole cell vaccine. The vaccines were well-tolerated. All acellular vaccines were associated with significantly fewer adverse reactions than the control whole cell vaccine.

Effect of gender, race, and parental education on immunogenicity and reported reactogenicity of acellular and whole-cell pertussis vaccines

OBJECTIVE

To determine whether gender, race (black or white), or level of parental education influenced serologic responses or reporting of clinical reactions after immunization with acellular (DTaP) or whole-cell (DTP) pertussis vaccine with diphtheria and tetanus toxoids combined.

METHODS

Healthy infants were prospectively randomized to receive one of 13 DTaP, Lederle DTP, or another DTP. Parents recorded the occurrence of adverse reactions for 2 weeks after each inoculation. Sera obtained before the first immunization and 1 month after the third immunization were analyzed for antibody to pertussis toxin, filamentous hemagglutinin, fimbriae, and pertactin (PRN). Chinese hamster ovary cell pertussis toxin neutralization assays were performed, and levels of agglutinating antibodies determined.

RESULTS

Prevaccination antibody levels did not differ by race, gender, or parental education. Postimmunization geometric mean titers (GMTs) were strongly and consistently associated with race. For both DTaP and DTP and for every included antigen, postimmunization GMTs were about twice as high for black as for white infants. Among DTaP recipients, these differences were significant for pertussis toxin, Chinese hamster ovary cell pertussis toxin neutralization assay, filamentous hemagglutinin, PRN, and agglutinins; among the much smaller sample of WCL recipients, the differences achieved or approached statistical significance for agglutinins, PRN, and fimbriae. These findings were confirmed by regression analyses that controlled for gender, parental education, study site, and preimmunization antibody level. Reported reactions were not correlated with parental education level and showed no material correlation with gender. Black infants were reported to have had more pain than white infants after receiving WCL and DTaP and were reported to be more fussy after receiving WCL.

CONCLUSIONS

The consistently higher postimmunization GMTs among black infants seems to be a real finding for which we have no explanation; the infants did not significantly differ by race in vaccine assignment, preimmunization antibody levels, age at immunization, or interval from immunization to phlebotomy. These observations should be confirmed and further evaluated in future pertussis vaccine trials. Reported differences by race in pain and fussiness after receiving WCL might reflect chance, differences by race in the occurrence of reactions, or differences by race in the reporting of reactions.

The effect of maternal antibody on the serologic response and the incidence of adverse reactions after primary immunization with acellular and whole-cell pertussis vaccines combined with diphtheria and tetanus toxoids

OBJECTIVE

To evaluate the effect of maternally derived antibody on the immunogenicity and reactogenicity of acellular (DTaP) or whole-cell (DTP) pertussis vaccine with diphtheria and tetanus toxoids combined.

METHODS

A total of 2342 infants were randomized to receive one of 13 DTaP or 2 DTP vaccines at 2, 4, and 6 months of age. The correlation between preimmunization and postimmunization antibody after three doses of vaccine and the relation between preimmunization antibody and adverse reactions after the first immunization were modeled by linear regression.

RESULTS

After DTP but not DTaP, higher levels of preexisting antibody were associated with substantial (28% to 56%) reductions in the subsequent antibody response to pertussis toxin (PT). For other pertussis antibodies, modest inverse correlations were seen between preexisting antibody concentrations and most postimmunization antibody responses (resulting in 8% to 18% reductions in postimmunization antibody) for both DTP and DTaP. There was no consistent association in any DTP or DTaP group between adverse reactions and preimmunization antibody levels.

CONCLUSION

The PT antibody response to DTaP, unlike DTP, is not adversely affected by preexisting antibody to PT. Inhibitory effects with respect to other antibodies, seen with both DTP and DTaP, were relatively modest. Our data suggest that the use of acellular pertussis vaccines in adults, which could confer higher levels of antibody in women before pregnancy, would be unlikely to adversely affect pertussis antibody responses after DTaP among infants born to mothers with high antibody levels.

Comparison of 13 acellular pertussis vaccines: overview and serologic response

OBJECTIVE

To compare the immunogenicity of a licensed conventional whole-cell (WCL) and 13 diphtheria-tetanus-acellular pertussis (DTaP) vaccines that differed in source, method of manufacture, and included antigens; all vaccines included diphtheria and tetanus toxoids.

METHODS

Healthy infants were enrolled through six university-based vaccine and treatment evaluation units and were randomized to receive one of the study vaccines at 2, 4, and 6 months of age. Sera were obtained before the first immunization and 1 month after the third immunization and were analyzed for antibody to pertussis toxin (PT), filamentous hemagglutinin, fimbriae, pertactin, and diphtheria and tetanus toxins. Chinese hamster ovary cell toxin neutralization assays were performed, and levels of agglutinating antibodies were determined.

RESULTS

Of 2342 infants enrolled, 1942 contributed usable preimmunization and postimmunization serum specimens. Each vaccine produced significant increases in antibodies directed against the included antigens; postimmunization antibody titers differed significantly among the DTaP vaccines. For each evaluated antigen, the majority of DTaP vaccines produced antibody responses that equaled or exceeded those produced by WCL. For some antigens (eg, PT), mean antibody levels by vaccine correlated poorly with the quantity of antigen included in each vaccine; for others (eg., fimbriae), there was a close correlation.

CONCLUSION

Although serologic correlates of pertussis immunity are not defined, it is clear that DTaP vaccines can stimulate immune responses that exceed those of licensed whole-cell vaccine with respect to the measured antibodies. Particularly for PT, immunogenicity seems to depend on factors in addition to antigen concentration, possibly including antigen derivation and formulation. No DTaP was most or least immunogenic with respect to all included antigens.

Association of reactions after consecutive acellular or whole-cell pertussis vaccine immunizations

OBJECTIVE

To evaluate the relative frequency of adverse reactions after initial and subsequent immunizations among infants receiving primary immunization with acellular (DTaP) or whole-cell (DTP) pertussis vaccine with diphtheria and tetanus combined.

METHODS

We examined the occurrence of common reactions in 2127 infants within 48 hours after immunization at 2, 4, and 6 months with one of 13 DTaP or with Lederle DTP (WCL). Data on at least two consecutive immunizations were available for 357 WCL recipients and 1770 DTaP recipients. For these analyses, reactions evaluated included fever of 100.4 degrees F (38 degrees C) or greater, redness of 21 mm or larger, swelling of 21 mm or larger, moderate or severe pain, moderate or severe fussiness, loss of appetite, drowsiness, and vomiting.

RESULTS

With one exception, reactions were approximately 1.5 to 8 times more likely to occur in WCL recipients if the same reaction had been observed at the previous immunization (the single exception was redness after the second immunization). Both initial and repeated reactions were less likely in DTaP than in WCL recipients. As with WCL recipients, risks of repeated reactions in DTaP recipients were higher than the risks of initial reactions (from 2.5 to 24 times as high).

CONCLUSION

Reactions after a second or third immunization with either WCL or DTaP vaccine are more likely to occur in infants who had the same reaction after the preceding immunization. Absolute risks of repeated reactions tended to be lower after DTaP vaccine than after the WCL vaccine.

A randomized comparison of reactogenicity and immunogenicity of two whole-cell pertussis vaccines

OBJECTIVE

To compare prospectively the reactogenicity and immunogenicity of two licensed whole-cell pertussis vaccines.

METHODS

We conducted a prospective, randomized, double-blinded assessment of two licensed whole-cell pertussis vaccines with diphtheria and tetanus toxoids that were included in a multicenter trial evaluating 13 acellular pertussis vaccines. Infants were immunized at 2, 4, and 6 months of age with a single lot of Lederle (309 infants) or Massachusetts Public Health Biologic Laboratories (MPHBL; 94 infants) vaccine.

RESULTS

The group receiving the Lederle vaccine demonstrated significantly higher antibody titers to pertussis toxin by enzyme-linked immunosorbent assay (ELISA) and by the Chinese hamster ovary cell pertussis toxin neutralization assay, and to fimbrial antigens by ELISA, as well as higher mean agglutinin titers. In contrast, the group receiving the MPHBL vaccine demonstrated higher ELISA antibody levels to filamentous hemagglutinin and pertactin. Similar differences were observed in the proportions of vaccinees seroconverting to these antigens. Rates of systemic and local reactions were relatively low for both vaccines. Although the Lederle product had substantially lower reactogenicity in this study than previously reported for that vaccine, the MPHBL vaccine was significantly less reactogenic in nearly all clinical categories.

CONCLUSION

The two whole-cell vaccines demonstrated statistically significant differences in postimmunization antibody levels to all six evaluated pertussis antigens. Whether these statistically significant differences in antibody levels have clinical relevance is not clear. Rates of nearly all local and systemic reactions were significantly lower among the MPHBL group than the Lederle group. Licensed whole-cell diphtheria-tetanus-pertussis vaccines produced by different manufacturers cannot be assumed to be similar in reactogenicity or immunogenicity.

Defining the key parameters for comparing reactions among acellular and whole-cell pertussis vaccines

OBJECTIVE

To facilitate future vaccine reaction data collection and analysis, we sought to determine the minimum data set required to describe accurately and to compare common reactions after the administration of acellular (DTaP) or whole-cell (DTP) pertussis vaccine with diphtheria and tetanus toxoids combined.

METHODS

Thirteen DTaP and 2 DTP vaccines were studied in a multicenter trial involving 2342 infants who received a primary series of vaccinations at 2, 4, and 6 months of age. Temperature, fussiness, redness, swelling and pain at the injection site, antipyretic use, drowsiness, loss of appetite, and vomiting were evaluated. Reactions were assessed at 3 hours and (if not immunized in the evening) 6 hours after immunization, at bedtime each evening for 7 evenings, and on the 14th evening after immunization.

RESULTS

Two reaction assessment approaches were compared: (1) analysis of all reactions, regardless of the degree of severity; and (2) a condensation of the data to five key reactions (fever > 100 degrees F, moderate or more fussiness, any local redness, any local swelling, and moderate or more local pain). We found that the onset of reactions was infrequent beyond the second evening, and that collection and analysis of reaction data beyond that time did not further discriminate among the vaccines. Information regarding antipyretic use, loss of appetite, drowsiness, or vomiting did not assist in differentiating among these vaccines.

CONCLUSION

Monitoring the occurrence of fever greater than 100 degrees F, moderate or severe fussiness, injection site redness or swelling, and moderate or severe injection site pain occurring through the second evening after immunization will provide the minimum data set needed to discriminate among DTaP and DTP vaccines with respect to the common adverse reactions.

Simultaneous administration of Haemophilus influenzae type b vaccine with acellular or whole-cell pertussis vaccine: effects on reactogenicity and immune responses to pertussis vaccines

OBJECTIVE

To evaluate the effect of simultaneous Haemophilus influenzae type b conjugate (Hib) vaccination on the safety and immunogenicity of selected acellular (DTaP) and whole-cell (DTP) pertussis vaccines with diphtheria and tetanus toxoids combined.

METHODS

Enrollment of infants into a large multicenter study of the safety and immunogenicity of 13 DTaP and 2 DTP vaccines was partially completed when the first Hib vaccine, HbOC (Haemophilus b oligosaccharide conjugate vaccine), was licensed for use in infants. Thereafter, at each immunization most infants received HbOC simultaneously with DTaP (or DTP), administered in opposite thighs. Postvaccination geometric mean titers or concentrations (GMTs) of pertussis antibodies as measured by six different assays were compared pairwise among groups of infants receiving 0, 1, 2, or 3 simultaneous HbOC immunizations. The incidence of reactions was compared between infants who received only DTaP or DTP and those who received HbOC simultaneously.

RESULTS

Comparison of postvaccination GMTs was possible among groups of infants receiving different numbers of simultaneous immunizations for 10 of the 13 DTaP and both DTP vaccines. Increased HbOC exposure had no consistent dose-response effect on antibody titers for DTaP or DTP vaccines in any assay. Significant differences between groups in postvaccination GMTs were observed with 4 DTaP vaccines in 1 to 2 assays each; the GMTs were higher with increasing HbOC exposure for 2 DTaP vaccines and lower for 2 others. There was no significant increase in reactions with simultaneous HbOC and DTaP immunization.

CONCLUSIONS

Based on these retrospective analyses, there did not seem to be an interference in pertussis immunogenicity or alteration in reactogenicity associated with the simultaneous administration of HbOC and DTaP. These findings are encouraging with respect to the development of DTaP-Hib combination vaccines.

Comparison of 13 acellular pertussis vaccines: adverse reactions

OBJECTIVE

To compare the reactogenicity of a licensed conventional whole-cell (WCL) and 13 acellular pertussis vaccines that differed in the source, manufacture, and quantity of included antigens; all vaccines included diphtheria and tetanus toxoids.

METHODS

Healthy infants were enrolled through six university-based vaccine and treatment evaluation units and were randomized to receive one of the study vaccines at 2, 4, and 6 months of age. Parents recorded the occurrence of fever, redness, swelling, pain, fussiness, drowsiness, anorexia, and use of antipyretics for 2 weeks after each inoculation; nurses interviewed parents on the third day and at each succeeding visit; long-term follow-up information was collected from parents and medical records 1 year after the third immunization.

RESULTS

Of 2200 vaccinated infants, 2189 contributed reaction data after 6375 vaccinations. For every acellular vaccine, every monitored reaction except vomiting occurred at a significantly lower frequency and severity than was seen with WCL. The groups receiving acellular pertussis vaccines differed significantly with respect to redness, swelling, pain, and vomiting, but not with respect to fussiness, antipyretic use, drowsiness, or anorexia.

CONCLUSION

Although there were differences among the acellular vaccines, none was consistently the most or least reactogenic; all were associated with substantially fewer and less severe adverse reactions than a standard commercial whole-cell vaccine. Selection of acellular vaccines for further development and for introduction into efficacy trials can give priority to assessments of immunogenicity and purity, with comparative reactogenicity a secondary consideration.

OSHA inspections. Workplace inspections

The Occupational Safety and Health Act of 1970 requires that every worker be provided with a safe and healthful workplace and authorizes the Occupational Safety and Health Administration (OSHA) to conduct workplace inspections. OSHA conducts workplace inspections in hospitals and checks for compliance with the Bloodborne Pathogens Standard, the Enforcement Policy and Procedures for Occupational Exposure to Tuberculosis, and the Hazardous Chemicals Standards, among others. The hospital epidemiologist bears considerable responsibility for developing and implementing plans to protect employees from occupational exposures to infectious hazards such as bloodborne pathogens and tuberculosis. To prepare for an inspection, the hospital epidemiologist must understand the basis on which OSHA operates and must proceed in a thoughtful, coordinated manner.

Respiratory protection standard: comments on OSHA's proposed revision

On November 15, 1994, the Occupational Safety and Health Administration (OSHA) published in the Federal Register (59:58884-58956) the draft of a proposed revision of the Respiratory Protection Standard. One of OSHA's oldest standards, the Respiratory Protection Standard defines the conduct of the employer (eg, hospital) with respect to respirator training, fit testing, medical examinations, use, storage, and so on. The proposed revision appears to have been drafted with no consideration for its effect on healthcare workers or the healthcare industry. SHEA has prepared the following comments to OSHA, which have been submitted to the docket and will be presented at public hearings later this month.

Pertussis infection in adults with persistent cough

OBJECTIVE

To determine the prevalence of Bordetella pertussis infection in adult patients with persistent cough.

DESIGN

Prospective case series.

SETTING

Urban university hospital emergency department.

PATIENTS

Convenience sample of 75 patients aged 18 years or older with a cough lasting 2 weeks or longer. Serum specimens from 67 patients without respiratory complaints were used to develop reference values.

INTERVENTIONS

In patients with cough, nasopharyngeal culture and direct fluorescent antibody testing for B pertussis were performed and serum samples were obtained at the first visit and 1 month later. Serum specimens were assayed for antibody to pertussis toxin (PT) and filamentous hemagglutinin (FHA).

MAIN OUTCOME MEASURES

A subject with one or more of the following was defined as having a pertussis infection: a positive B pertussis culture result, a four-fold change in PT or FHA titer, and/or a single PT or FHA titer at least 2 SDs greater than the geometric mean of the control group.

RESULTS

No subject tested culture positive for B pertussis. Sixteen (21%) (95% confidence interval [CI], 13% to 32%) of 75 subjects met the serologic criteria for pertussis infection; for 13 (81%; 95% CI, 54% to 96%) of the 16, the criteria were met by the initial serum specimen. In contrast, the geometric mean levels of antibody to PT and FHA for the remaining 59 subjects with cough did not differ from those of the control group. Clinical symptoms and the lymphocyte count did not differentiate patients with pertussis from those without the disease.

CONCLUSION

Pertussis is a common cause of persistent cough in adults and should be considered in the differential diagnosis. Clinical symptoms, pertussis culture, direct fluorescent antibody testing, and lymphocytosis are of limited value in making the diagnosis.

Interchangeability of conjugated Haemophilus influenzae type b vaccines in infants

OBJECTIVE

To evaluate the safety and immunogenicity of two Haemophilus influenzae type b (Hib) conjugate vaccines when administered in serial combination. These vaccines consisted of Hib capsular polysaccharide polyribosyl-ribitol phosphate (PRP) conjugated to the meningococcal outer membrane protein (OMP) complex (PRP-OMP) and H influenzae oligosaccharide conjugated to a mutant toxin (CRM197) isolated from Corynebacterium diphtheriae (HbOC).

DESIGN

Randomized, double-blind, clinical trial evaluating five Hib vaccination regimens.

SETTING

Vaccine Treatment and Evaluation Units and affiliated private pediatric practices at Saint Louis (Mo) University, Vanderbilt University, Nashville, Tenn, and Baylor College of Medicine, Houston, Tex.

PATIENTS

A total of 497 healthy 2-month-old infants scheduled to receive routine immunization.

INTERVENTION

Participants received either PRP-OMP or HbOC given as recommended by the manufacturer, PRP-OMP at 2 and 6 months, HbOC at 2 months, then PRP-OMP at 4 and 6 months, or PRP-OMP at 2 months and then HbOC at 4 and 6 months. Unconjugated PRP was given at 15 months to evaluate priming.

RESULTS

Geometric mean antibody concentrations differed significantly among the groups following the second and third immunizations of the primary series and following booster immunization with unconjugated PRP. On each occasion, the groups receiving serial combinations of PRP-OMP and HbOC achieved mean antibody concentrations that equalled or exceeded those of the groups receiving a single product. Adverse reactions did not vary by group.

CONCLUSIONS

The studied sequential combinations of Hib vaccines were safe and at least as immunogenic as either vaccine alone.

Pertussis seroprevalence in emergency department staff

STUDY OBJECTIVE

The purpose of this study was to look at the prevalence of pertussis immunity in emergency department employees.

DESIGN

Prospective, observational study conducted in September 1992.

SETTING

A university hospital ED.

PARTICIPANTS

A convenience sample of 73 ED employees.

INTERVENTIONS

Blood was collected from ED staff and assayed for antibody to pertussis toxin and filamentous hemagglutinin.

RESULTS

Ninety-nine percent of the subjects reported childhood immunization. Geometric mean titers were 3.6 (geometric SD, 3.2) enzyme-linked immunosorbent assay (ELISA) units for pertussis toxin and 12.1 (geometric SD, 3.3) ELISA units for filamentous hemagglutinin. These titers are comparable to those previously reported in other adults not immunized since childhood and are substantially lower than the levels commonly seen in children or adults following immunization. Titers did not differ significantly between male and female subjects or between subjects with or without a recent prolonged cough, family members with a cough, or small children in the household.

CONCLUSION

Most ED staff members have low levels of antibody to pertussis and may be at risk for acquiring the disease from infected children or adults, with subsequent risk of transmission to susceptible patients. Booster immunization with an acellular pertussis vaccine has been shown to be safe and immunogenic in adults and may be appropriate for adult ED personnel to reduce these risks.

Enhanced antibody response in Venezuelan infants immunized with Haemophilus influenzae type b-tetanus toxoid conjugate vaccine

The safety and immunogenicity of primary immunization at 2, 4 and 6 months of age with Haemophilus influenzae type b capsular polysaccharide conjugated to tetanus toxoid (PRP-T; Act-HIB) were evaluated in infants in Valencia, Venezuela. In order better to assess reactions to PRP-T, subjects received their initial PRP-T vaccine a mean of 6.5 days after their initial diphtheria-tetanus-pertussis (DTP) vaccine. The PRP-T vaccine was well tolerated. Serum was obtained at ages 2 and 7 months (before the first and 1 month after the third PRP-T dose). Antibody responses were compared with those from Nashville infants who had received PRP-T and DTP simultaneously in a previous trial. The preimmunization titers in the Venezuelan and Nashville infants did not differ. The geometric mean postimmunization titer in the Venezuelan infants was 37.9 micrograms/ml, as compared with 3.63 micrograms/ml in the Nashville infants (P < 0.00001). Possible explanations for the exceptional antibody response of these Venezuelan infants to PRP-T include carrier priming caused by prior DTP immunization, synergy associated with the specific DTP vaccine used, preimmunization immunologic experience that differed from their United States counterparts and genetic differences that altered response to the vaccines. Further studies are proposed to evaluate these possibilities.

Serologic response to standard inactivated influenza vaccine in human immunodeficiency virus-infected children

We compared the serologic response of 46 human immunodeficiency virus (HIV)-infected children and adolescents and 61 age-matched controls to standard trivalent inactivated influenza vaccine (A/Taiwan (H1N1), A/Shanghai (H3N2), B/Yamagata). Children were immunized according to the package insert recommendations before the 1990 to 1991 influenza season. Serum antibody titers to influenza A were determined before and 1 month after each vaccination and compared for study and control subjects. Serologic responses of HIV-infected participants were correlated with absolute CD4 counts and stage of HIV disease. Regardless of age or HIV status, all groups responded with significant increases in antibody to the influenza A strains (range, 2.1-fold to 11.8-fold), with the exception that antibody to H3N2 rose only 1.5-fold (P = 0.058) among HIV-positive subjects > or = 9 years old. Pre- and postimmunization antibody titers were significantly higher for controls than for HIV-positive subjects. There was no correlation between serologic responses and CD4 counts among HIV-infected subjects, but those with Centers for Disease Control and Prevention-defined acquired immunodeficiency syndrome responded significantly less well to vaccine. We conclude that HIV-infected children and adolescents produce significant antibody rises after inactivated influenza A vaccination but that their absolute antibody concentrations are lower than those seen in age-matched controls.

Acellular and whole-cell pertussis vaccines as booster doses: a multicenter study

OBJECTIVE

To compare the safety and immunogenicity of a variety of acellular (AC) and whole-cell (WC) pertussis vaccines combined with diphtheria and tetanus toxoids.

METHODS

Standard enrollment and reaction forms were used at five sites, and serologic evaluation was performed at a single site. Nine AC (Massachusetts Public Health Laboratories, Biocine Sclavo recombinant pertussis toxoid [PT], Connaught/BIKEN, Lederle three-component, Biocine Sclavo recombinant three-component, SmithKline Beecham three-component, Porton three-component, Takeda-Wyeth, and Connaught multicomponent), and three WC (Connaught Laboratories, Lederle Laboratories, and Massachusetts Public Health Laboratories) were studied. All AC contained varying concentrations of PT; some vaccines also contained filamentous hemagglutinin (FHA), pertactin, and/or agglutinogens.

RESULTS

Two hundred forty children, aged 16 to 21 months and 4 to 6 years, were enrolled at five sites. Significantly less fever, redness, swelling, pain, limp, and use of pain medication were noted following AC compared with WC. Significant increases in antibody to PT were seen following all vaccines. Significant rises in FHA antibody were seen following all WC and the seven AC that contained FHA. Postbooster PT antibody levels were similar among the AC groups, regardless of the amount of PT administered (between 3.5 and 25 micrograms per dose). The dose of FHA did not affect PT antibody response. Infants primed with WC who were boosted with a monocomponent PT vaccine did not manifest a significant antibody response to FHA.

CONCLUSION

The rate of adverse reactions was not a function of the number of antigens or the antigen quantity in the acellular vaccines, and antibody responses following AC were similar or better than antibody responses following WC. These results support the further evaluation of these vaccines in a larger National Institute of Allergy and Infectious Diseases-sponsored study in infants.

Continuous quality improvement and hospital epidemiology: common themes

Recently, many have begun to explore the possibility of using analytical methods associated with continuous quality improvement in the efforts to improve health care. Central to this paradigm is the proposition that such analytical methods can be used to identify and react to variations in the processes and outcomes of care. These methods and principles are remarkably similar to those employed by hospital epidemiologists. This article explores the similarities between these fields in an attempt to bring together leading thinkers in both disciplines.

Responses of children to booster immunization with their primary conjugate Haemophilus influenzae type B vaccine or with polyribosylribitol phosphate conjugated with diphtheria toxoid

Children primed with one of four conjugate Haemophilus influenzae type b vaccines received booster immunization with their primary vaccine or with polyribosylribitol phosphate conjugated with diphtheria toxoid. The latter vaccine produced postbooster antibody levels that equaled or exceeded those produced by boosting with the original vaccine, and thus may be used as a booster irrespective of the original vaccine.

Adult immunization with acellular pertussis vaccine

OBJECTIVE

To evaluate the safety and immunogenicity in adults of several different concentrations of an acellular pertussis vaccine.

DESIGN

Double-blind, randomized, placebo-controlled trial.

SETTING

Medical center immunization clinic.

PARTICIPANTS

One hundred eighteen healthy adult volunteers.

INTERVENTIONS

Participants received standard adult tetanus-diphtheria vaccine alone or combined with full-strength, half-strength, or quarter-strength concentrations of a currently licensed acellular pertussis vaccine used for booster doses in young children. Full-strength vaccine contained 40 micrograms of pertussis proteins, consisting of 86% filamentous hemagglutinin, 8% pertussis toxin, 4% 69-kd outer-membrane protein, and 2% agglutinogens.

MAIN OUTCOME MEASURES

Local and systemic reactions were assessed for 14 days after vaccination. Serum samples for antibody assay were obtained before, 1 month after, and 1 year after immunization.

RESULTS

Adverse reactions were few and minor and did not differ in frequency or severity among the four study groups. The groups receiving acellular pertussis vaccine showed strong antibody responses to pertussis antigens, which did not significantly differ by concentration of vaccine. After 1 year, levels of antibody to pertussis had declined by approximately 50% but remained substantially higher than preimmunization levels. The four groups did not differ in antibody responses to tetanus or diphtheria toxoids.

CONCLUSIONS

Routine reimmunization of adults with a vaccine containing acellular pertussis antigens in addition to diphtheria and tetanus toxoids can substantially enhance pertussis antibody levels without an increase in adverse reactions or diminution in response to the diphtheria and tetanus components. Such a program might materially reduce respiratory illness among both adults and children.

Psychoactive drugs and the risk of injurious motor vehicle crashes in elderly drivers

To determine whether commonly used psychoactive drugs increase the risk of involvement in motor vehicle crashes for drivers > or = 65 years of age, the authors conducted a retrospective cohort study. Data were obtained from computerized files from the Tennessee Medicaid program, driver's license files, and police reports of injurious crashes. Cohort members were Medicaid enrollees 65-84 years of age who had a valid driver's license during the study period 1984-1988 and who met other criteria designed to exclude persons unlikely to be drivers and to ensure availability of necessary study data. There were 16,262 persons in the study cohort with 38,701 person-years of follow-up and involvement in 495 injurious crashes. For four groups of psychoactive drugs (benzodiazepines, cyclic antidepressants, oral opioid analgesics, and antihistamines), the risk of crash involvement was calculated with Poisson regression models that controlled for demographic characteristics and use of medical care as an indicator of health status. The relative risk of injurious crash involvement for current users of any psychoactive drug was 1.5 (95% confidence interval (CI) 1.2-1.9). This increased risk was confined to benzodiazepines (relative risk = 1.5; 95% CI 1.2-1.9) and cyclic antidepressants (relative risk = 2.2; 95% CI 1.3-3.5). For these drugs, the relative risk increased with dose and was substantial for high doses: 2.4 (95% CI 1.3-4.4) for > or = 20 mg of diazepam and 5.5 (95% CI 2.6-11.6) for > or = 125 mg of amitriptyline. Analysis of data for the crash-involved drivers suggested that these findings were not due to confounding by alcohol use or driving frequency.