Distinct immunity in patients with visceral leishmaniasis from that in subclinically infected and drug-cured people: implications for the mechanism underlying drug cure.

Significant levels of IgG3 and IgG4 and high levels of IgG1 leishmania-specific antibody differentiated the immune states in 10 patients with visceral leishmaniasis from those of virtually all 20 drug-cured and 18 subclinically infected subjects, whereas the level of IgG2 antibody was nondiscriminating. The most extreme "subclinically infected" outlier subsequently developed disease. Overall, the immune states in subclinically infected and drug-cured persons were mutually indistinguishable but were readily distinguished from those of patients. These findings may have implications for the immunologic mechanism underlying drug cure in visceral leishmaniasis.

Information and patient participation in screening for prostate cancer.

The purpose of this study was to determine if providing men with information about screening for prostate cancer would enable them to assume a more active role in decision making with their family physician, and lower levels of anxiety and decisional conflict. Men were recruited from one family medical clinic in Winnipeg, Manitoba. One hundred men scheduled for a periodic health examination (PHE) were randomly assigned to receive verbal and written information either prior to the PHE, or following the second interview. Men completed measures of preferred decisional role and anxiety prior to the PHE; and assumed decisional role, decisional conflict, and anxiety post PHE. Results demonstrated that men who received the information prior to the PHE assumed a significantly more active role in making a screening decision, and had lower levels of decisional conflict post PHE. The two groups did not differ with regard to levels of state anxiety. Providing men with information enables them to make informed screening decisions with their family physicians.

Surveillance of vaccine-related adverse events in the first year of life: a Manitoba cohort study.

This study used data from the population database through which the province of Manitoba, Canada, administers its universal health insurance plan. Enrollment, hospitalization, and immunization files from children born in the 1987-1989 period were linked using the unique identification number assigned to each population member. Analysis of these linked data successfully identified serious potential adverse events in the first year of life and the timing of events around immunization. Not only is population-based active surveillance for immunization-related events feasible, but the techniques described, applied to years of data accumulated through surveillance, offer powerful research tools. Baseline population incidences of adverse events were calculated, temporal relationships between events and immunization assessed, and incidences for events showing true temporal associations determined. Eventual goals are the quantification of vaccine-related risk and the gathering of evidence concerning casual associations. The approach could be used readily by several other Canadian provinces and by health maintenance organizations in the United States.

Predetermination as a cost-containment mechanism in a social allowances dental program in Manitoba.

OBJECTIVES: A review of dental consultant actions during predetermination of benefits in the publicly insured indemnity program in Manitoba under which Social Allowances Health Services certificate holders receive dental care was undertaken to determine the value of this process as a cost-containment mechanism. METHODS: Dollar amounts of services denied by a dental consultant during eight predetermination sessions selected to represent the 96 sessions during the 1990-91 fiscal year were determined and grouped according to category of service. RESULTS: Approximately one-third of average total expenditures each month were reviewed by the dental consultant through the predetermination process. Of the requested dollar amount reviewed, 26 percent was denied, a savings of 8.5 percent of average total monthly expenditures. The categories of services that made up the denied requests were: prosthodontics (30%); endodontics (32%); restorative (5%); periodontics (12%); and miscellaneous (21%), including diagnostic, surgical, preventive, orthodontic, and adjunctive. CONCLUSIONS: A properly administered predetermination process can save a third party 8.5 percent of total plan expenditures; dollar changes to altered treatment plans amount to a 26 percent reduction of expenditures relating to these requests. A predetermination process with an unbiased appeal mechanism provides a system to advise and protect providers regarding what treatment is covered.

Comparison of the dental health status of six-year-old children in Manitoba.

The caries rates of six-year-old Manitoba children from a non-fluoridated Northern community were compared with those of a representative group of southern Manitoba children from non-fluoridated areas. All of the surveyed children became eligible for dental treatment coverage under Manitoba Health's Children's Dental Program approximately two months prior to the survey. Access to dental care was equivalent for all children. Screening (data collection) was completed by Manitoba Dental Health staff and was based on standard World Health Organization (WHO) criteria. The initial assessment of the data indicated that the Northern Manitoba children experienced an average of 82 per cent more decay per child than the southern group. Caries treatment requirements in the north were 59 per cent greater than in the south. The southern Manitoba children were almost twice as likely to be caries free than the Northern children. Closer examination of the Northern data, based on a socioeconomic delineation, indicated that the Northern middle- to high-income group experienced 24 per cent more decay per child than the southern group. The Northern middle- to low-income group experienced 124 per cent more decay per child than the southern group. In this study, it was demonstrated that although increased dental caries experience was closely related to geographic location, socioeconomic factors may play an even greater role in dental caries experience.

Evaluating medical performance in the diagnosis and treatment of occupational health problems: a standardized patient approach.

Primary care physicians must identify and manage work-related disease, yet it is unclear whether training is adequate to accomplish this. This study examines the performance of 110 candidates, including 93 4th-year medical students, in the diagnosis and treatment of a standardized patient with occupational illness. Results indicated that the students did substantially better than the medical practitioners who had not received recent training. Although a strong correlation existed between candidates performance on the occupational health (OH) case and overall score on 19 non-occupational health cases, the competency measure that most determined performance on the OH case was interpersonal skills. A correlation also existed between working knowledge, data collection and data interpretation skills overall, and performance on the OH case; diagnostic skills, test selection, test interpretation, and case management skills overall showed no such correlation. The findings highlighted the importance of emphasizing interpersonal skills in training physicians to appropriately manage occupational medical cases, and illustrated the usefulness of standardized patients in teaching and evaluating occupational medical skills.

Performance and perception in a simulated clinical encounter.

The feasibility of using data arising from a simulated patient encounter to determine the nature of the relationship between patient satisfaction and examinee performance during a clinical examination is explored. Satisfaction (on dimensions of sensitivity, participation and thoroughness) is shown to be related to aspects of the physical examination and the history taking.

Hearing aids poststapedectomy: incidence and timing.

Ninety-four percent of 508 patients operated on between 1960 and 1975 have been followed-up at yearly intervals. Their status as of 1977 was assessed in order to determine their mean duration of socially adequate hearing levels and to relate the type of surgical procedure to the interval between operation and hearing aid requirement. Postoperative hearing losses due to conduction and sensorineural deficits resulted in preoperative bone/postoperative air gaps greater than 10 dB in up to 40% of large fenestra operations and in 15% of small fenestra operations at 5 years. On average, a large fenestra ear would require amplification at 13 years and a small fenestra ear at 21 years postoperatively.

The 'induction' dose of thiopentone. A method of study and preliminary illustrative results.

Study of the minimal dose requirements for induction of anaesthesia poses great problems which are solved by the use of a standard administration technique and the abolition of the eyelash reflex as an endpoint. This has been used in 2206 consecutive unselected inductions, in which variables considered to be likely to influence the dosage were recorded. Milligram per kilogram is the most acceptable method of expressing the average dosage of thiopentone. Doses follow a right skew distribution. Women required a significantly lower average dose of thiopentone than men, while obese patients required less than others. Moderate or heavy drinking increased the induction dose but the use of tobacco did not have any influence. The most important factors governing dosage are the physical fitness of the patient and the premedication used. Patients in ASA grades 1 and 2 required significantly more thiopentone than those in grades 3 and 4. This effect is as great as that of premedication in which an opiate with a phenothiazine or hyoscine markedly reduced the induction dose. It was more important than the patient's pre-operative condition with respect to sedation or apprehension. Small doses of opiates or benzodiazepines do not have as much effect on dosage.

A reconsideration of the parameters for evaluating tympanic reconstruction.

Twenty years' experience with tympanoplasty operations incorporating ossicular reconstruction revealed some unexpected improvements in bone conduction thresholds postoperatively. Because there appeared to be a relationship between this occurrence and the degree of air-bone closure, the possibility that bone conduction thresholds were related to the efficiency of the middle ear sound transformer mechanism was investigated. It has been possible to demonstrate that such a relationship does exist. Its extent and the possible underlying mechanisms are discussed. It is concluded that the evaluation of ossiculoplasty results would be more realistic if they were based on a parameter that measures cochlear function with greater accuracy than do preoperative bone conduction thresholds.

The surgical treatment of vertigo. The essentials of patient selection and long-term results.

The essential features of the posturing and positional mechanisms in man are defined and the causes of their dysfunction categorized to provide a scheme of surgical management appropriate for each. The authors' long-term results (two to twelve years) with (1) twenty-seven operations designed to decompress the endolymphatic system, (2) twenty-eight selective eighth nerve sections are documented and compared, by means of statistical analysis, with those reported by others during the past fifteen years. Although the latter procedure provided better control of vertigo, there was no difference between the two groups in regard to preservation of hearing. Nor was there any evidence from this study that either operation did anything to alter the progressive hearing loss that characterizes Meniere's disease. Nevertheless, because of failure of noninvasive therapy to control vertiginous symptoms in some patients, it would appear that there is still a definite place for surgical treatment. Saccus decompression is recommended as the initial procedure because it is technically less difficult. In patients whose vertigo persists in conjunction with useful auditory function vestibular nerve section should be considered before resorting to total labyrinthectomy.

Postoperative cholesteatoma: are claims for the canal wall down technique justified?

To discover whether removal of the canal wall would reduce the incidence of postoperative cholesteatoma in tympanoplasty, the findings in staged, intact canal wall tympanoplasties were compared with those in staged, modified radical mastoidectomies with cavity obliteration and tympanoplasty. In all, cholesteatoma was considered totally removed at the first operation. The incidence of residual cholesteatoma was not significantly different in either group. It is concluded that staging in tympanoplasty for cholesteatoma is mandatory.

Tympanoplasty in children.

To evaluate the possibility that current teaching regarding the postponement of tympanoplasty as desirable in young patients might be less correct than previously thought, the results in 260 ears in patients aged less than 16 years were scrutinized. It was found that not only were the functional results comparable to those obtained with adult patients, but also that there was little evidence of subsequent deterioration of initially good hearing results with time. The findings in regard to postoperative cholesteatomatous complications were in agreement with those previously reported and were not different from those in adult patients. It is concluded that, with children, in the interests of health, educational progress and social integration, tympanoplasty procedures, often in two stages, should be carried out as soon as concomitant upper respiratory disease is brought under control. Childhood cholesteatoma is not a "different" disease. Functional results are the same as with adults and are influenced by identical deficiencies in our technical ability.