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J K Todd

Publications and source records attributed to J K Todd.

97 records · Page 6Linked to original sources

Criteria for the evaluation of new diagnostic tests.

The overall scheme for evaluating a new diagnostic test is presented in Fig. 2. The office-based practitioner has encountered a new diagnostic test (A). The purpose of the new test seems to be one that would be useful in an office practice, for the suspected disease is seen frequently enough to justify stocking an office test (B), and the benefits of the test, if true, would augment the delivery of patient care (C). From the manufacturer, appropriate literature references are obtained which compare the new test with either the current office test or an accepted standard; the article is from a peer review journal (D). This article is then examined more carefully (E). The conclusions contained in the Abstract, if true, would lead the practitioner to change his current office procedure. The Methods section of the article is now examined for evidence that an independent clinical standard of comparison was used; a patient population was described similar to that in the office practice; a wide spectrum of disease presentations was evaluated; a sensible definition of "normal" was utilized; the study was "blinded" to avoid bias; and a detailed description of the test techniques was provided. In the Results section, one notes the precision and inter-observer variability of the test, and an appropriate statistical analysis is verified. Finally, the Discussion is skimmed to find out whether the authors have commented on the utility of the test in an office setting.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnostic Tests, Routine↗

Office laboratory diagnosis of skin and soft tissue infections.

Some skin and soft tissue infections can be treated empirically without culturing. Some infectious sites should be cultured before initiating antimicrobial therapy. When there is a choice, permissive swab specimens are never as good as nonpermissive aspirate specimens. Swab specimens should be cultured semiquantitatively on agar media only in an attempt to distinguish normal flora contaminants from the infecting pathogen. Needle aspirate specimens can be obtained at most infectious sites invoking Sutton's law ("Go where the money is.") to identify the point of maximal involvement. Office laboratory identification in general should be limited to the identification of yeast forms on Gram stain and the initial separation of Group A streptococci from staphylococci. Other organisms should be sent to a referral laboratory for further identification and susceptibility testing.

Biopsy, Needle↗

Comparative evaluation of kits for rapid diagnosis of group A streptococcal disease.

The role of rapid diagnostic tests for Group A streptococcal disease has not been firmly established. High quality data concerning these rapid streptococcal tests are not available; current information does not allow for direct test comparisons to be made; the superiority of rapid diagnostic technology over traditional throat cultures has not been proved. Subgroups which might benefit from this technology could include those who (1) are severely ill, (2) have been excluded from school or day care because of a streptococcal infection, (3) have a history of rheumatic fever and are not taking antimicrobial prophylaxis or (4) live in a confined residential setting. Each available test kit has a mixture of performance features, allowing for individual choices based on office and practice needs. Product technology is expected to change rapidly. Reassessment of any current decision may well lead to a different conclusion in 6 to 12 months.

Evaluation Studies as Topic↗

Outbreak of group A streptococcus septicemia in children. Clinical, epidemiologic, and microbiological correlates.

OBJECTIVE: To determine the epidemiologic, clinical, and microbiological features of group A streptococcus septicemia in children. DESIGN: A descriptive series of 34 cases over an 11-year period from 1980 through 1990. SETTING: An academically affiliated tertiary-care pediatric hospital, the principal referral center for the state of Colorado and surrounding states. PARTICIPANTS: Thirty-four patients with positive blood cultures for group A streptococcus (33 medical records were available). MAIN OUTCOME MEASURES: Yearly incidence and clinical features of cases; microbiological features of isolated organisms. RESULTS: There was a significant increase (P = .01) in the incidence of group A streptococcus bacteremia over an 11-year period, with 14 (41%) of these cases occurring in 1989 and 1990. Patients had a rapidly progressing illness, usually without preceding pharyngitis. The prominent M and T types were 1 (4) and 12 (4). Eleven (73%) of the 15 strains produced pyrogenic exotoxin B that significantly correlated with production of proteinase. CONCLUSION: There appears to be an increase in group A streptococcus bacteremia in children that is associated with a strain phenotype that suggests a change in organism virulence.

Adolescent↗