False-positive tuberculin skin tests in a state prison system

OBJECTIVE

To assess the existence and extent of false-positive tuberculin skin test (TST) results in a regularly tested population subsequent to switching to a different skin testing product.

METHOD

Over 9300 state prison inmates were tuberculin skin tested as part of a routine annual testing program. A shortage of Tubersol caused the prison system to purchase and test with Aplisol. Prison health services staff reported an apparent increase in skin test positivity using Aplisol compared to Tubersol. Record reviews were conducted in 34 prisons where inmates read as positive (> or = 5 mm) were retested with Tubersol.

RESULTS

Among 368 inmates recorded as positive (> or = 5 mm) with Aplisol who were retested with Tubersol, 150 (40.8%) were read as negative (0-4 mm).

CONCLUSION

The tuberculin skin test is a valuable tool in evaluating patients for TB infection. However, variations in planting and reading the test, and in the consistency between lots and manufacturers, can contribute to errors in determining an individual's infection status. The entire clinical and epidemiological picture for each patient must always be evaluated using the TST as a tool, and not an indisputable answer.

Maze procedure and homograft replacement of a rheumatic mitral valve

A 64-year-old woman presented with congestive heart failure due to severe mitral valve stenosis and chronic atrial fibrillation. A Maze III procedure was performed, and the mitral valve replaced with a mitral homograft. Postoperatively, the patient regained normal sinus rhythm, had trivial mitral regurgitation, regained her atrial transport function, and had improved myocardial function.

Long-term follow-up of an alternative medical curriculum

BACKGROUND

The Alternative Curriculum (AC), an elective program at the University of Virginia School of Medicine that enrolled a total of 48 students in 1973 and 1974, was one of many demonstration and pilot programs conducted during the 1970s. Its principal features were (1) a three-year time span; (2) early, prolonged, and intensive instruction in clinical skills; (3) intensive consideration of behavioral, social, economic, ethical, and legal aspects of medicine in a patient-centered curriculum; (4) an extensive course in sexuality; (5) an independent study format for two preclinical courses; (6) instruction in cardiopulmonary resuscitation; and (7) participation in the activities of the local rescue squad. In view of continuing questions about the structure and content of medical school curricula, it seemed worthwhile to try to determine what effects the program might have had on the participants during medical school and in their subsequent careers.

METHODS

In 1991, data on the AC participants were collected, largely by means of a survey but also by examination of the participants' medical school records and determination of their current professional status.

RESULTS

Of the 48 participants, 44 were available for the survey, and 37 returned completed questionnaires. The great majority of the respondents had positive opinions about the program's three-year time span, morale during the program, and beneficial effects of the program's special content during their clerkships, postgraduate training programs, and subsequent careers. They thought they had had enough time to make informed specialty choices and did not think that their participation in the AC had been a handicap in getting the internships they wanted. Fewer than half of the students thought that the AC had influenced their career choices, and only 26% were currently in primary care specialties.

CONCLUSION

The AC was successful in improving students' morale during the preclinical segment, preparing them for clerkships, and increasing their sensitivity to the patient as a whole. That the program was not effective in inducing students to enter primary care specialties supports the view that curriculum content is not a major factor in students' choices of specialty.

Magnetic resonance imaging in ischemic injury after heart transplantation in rats

Magnetic resonance imaging with and without gadolinium (Gd)-DTPA has been shown to enable detection of coronary occlusive ischemic injury and heart transplant rejection. This study was performed to examine findings on magnetic resonance images associated with ischemic injury after heart transplantation in rats. Magnetic resonance imaging was performed immediately before death in 22 rats, between 1 and 90 days after isogeneic (Lewis grafts, Lewis host; or Fischer graft, Fischer host) heterotopic heart transplantation. Ischemic injury, characterized histologically by cellular infiltration or myocyte necrosis, correlated inversely with graft duration. It was graded as moderate to severe in 5 of 5 rats killed at 1 to 2 days, and in 0 of 9 animals killed at greater than or equal to 30 days. T2-weighted myocardial signal intensity (TR = 2.3 seconds; TE = 90 milliseconds) correlated inversely with graft duration and was significantly greater in grafts with moderate or severe histologic abnormalities than in grafts with absent or minimal changes. GD-DTPA-induced myocardial enhancement was judged on T1-weighted images (TR = 0.5 seconds, TE = 25 milliseconds). Areas of intense enhancement were present in all seven grafts with severe histologic abnormalities, but in only 3 of 15 grafts with absent to moderate histologic abnormalities. In conclusion, after heart transplantation in rats, ischemic injury causes increased T2-weighted signal intensity and Gd-DTPA-induced T1-weighted signal enhancement--findings similar to those described in transient coronary occlusive ischemia and in graft rejection. Abnormalities seen on magnetic resonance images during the first few posttransplant weeks may represent ischemic injury rather than rejection.

Bile duct cancer

Bile duct cancer, although not among the common tumors, still accounts for more than 4,000 deaths a year in the United States. Clinicians caring for these patients are faced with difficulties in diagnosis, even with the best of modern imaging techniques, and if the tumor is not resectable (as is true for about 75 percent of all patients), the mean survival time is only a few months. Endoscopic diagnostic and therapeutic techniques have improved markedly. As with other malignant tumors, biliary cancer is best managed by a multidisciplinary team approach.

Accuracy and cost-effectiveness of fine needle aspiration biopsy

Two hundred eighty-six fine needle aspiration biopsies were reviewed. The sensitivity for the diagnosis of malignancy was 90 percent for lymph node specimens, 93 percent for skin and soft tissue masses, and 74 percent for breast cancer. The overall accuracy of the technique was 82 percent for breast lesions, and 90 to 92 percent for soft tissue and lymph node lesions. Traditional open biopsy in an outpatient setting for these tumors is twice as costly as fine needle aspiration biopsy. Further refinement in the use of the cytocentrifuge and immunohistochemical techniques will result in fewer inadequate fine needle aspiration specimens and an increase in the diagnostic information available with this technique. Fine needle aspiration is recommended as the first biopsy technique of choice for localized solid tumors.

Increased oxidation of a chemical carcinogen, benzo(a)pyrene, by colon tissue biopsy specimens from patients with ulcerative colitis

Colonic biopsy specimens from patients with ulcerative colitis and normal subjects were studied for the ability to metabolize an environmental carcinogen, benzo(a)pyrene. Approximately 73% of 30 colonic biopsy specimens from 7 ulcerative colitis patients could metabolize benzo(a)pyrene to oxidized products, with an average production of 11.6 nmol/mg biopsy protein. In contrast, 39% of 23 biopsy specimens from 5 normal persons showed metabolic activity, with an average of 2.79 nmol benzo(a)pyrene metabolites/mg biopsy protein. Thus, benzo(a)pyrene oxidation activity in colonic tissue from colitis patients was, on the average, fourfold greater than that in normal subjects. This elevated metabolic activity appeared to be unrelated to the state of inflammation in the biopsy section. There was a tendency toward increased metabolic activity in the distal colon. Although there is no evidence that benzo(a)pyrene itself is "the colon carcinogen," this chemical belongs to a broad class of environmental carcinogens, the polycyclic aromatic hydrocarbons. Our findings suggest that the colonic mucosa of patients with ulcerative colitis has a greater ability than that of normal subjects to oxidize such chemicals possibly to electrophiles with higher mutagenic potential.

A computer-assisted surgical pathology system

SURPATH is a comprehensive, integrated computer-assisted system for service, research, and management in surgical pathology that has been in use at New England Medical Center (NEMC) since July 1, 1978. Functions of the system include: maintenance of patient-name and diagnostic files; generation, editing, and printing of preliminary and final specimen reports; SNOMED coding and indexing of diagnoses; retrieval and video display or printing of data on individual cases or groups of cases; billing and generation of billing reports; and, calculation of intervals between accession and signout of specimens. Use of the system has greatly facilitated the production of surgical pathology reports; increased the spread with which inquiries about individual specimens can be answered; provided rapid, accurate searches of the diagnostic files; improved timeliness, accuracy, and completeness of billing resulting in increased departmental revenue; reduced intervals between accession and reporting; and, improved the morale of the professional and support staffs.

Tissue injury by toxins in experimental staphylococcal infections. Effect of polyvalent antitoxin on developing renal lesions

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Hemolysin production in the development of staphylococcal lesions

The presence of hemolysin in staphylococcal lesions of the rabbit kidney was detected by overlaying sections of kidney with blood agar. Hemolytic activity against rabbit, human, sheep, calf, and guinea pig erythrocytes was present and was not abolished by heating the sections to 60 degrees C for 30 minutes. In developing lesions, hemolytic activity appeared before necrosis or exudation.