Outcomes assessment of a residency program in laboratory medicine.

During a down-sizing of residency programs at a State University Medical School, hospital based residents' positions were eliminated. It was determined to find out the characteristics of the residents who graduated from the Laboratory Medicine Program, to compare women graduates with men graduates, and to compare IMGs with United States Graduates. An assessment of a 25 year program in laboratory medicine which had graduated 100 residents showed that there was no statistically significant difference by chi 2 analysis in positions (laboratory directors or staff), in certification (American Board of Pathology [and subspecialties], American Board of Medical Microbiology, American Board of Clinical Chemistry) nor in academic appointments (assistant professor to full professor) when the male graduates were compared with the female graduates or when graduates of American medical schools were compared with graduates of foreign medical schools. There were statistically significant associations by chi 2 analysis between directorship positions and board certification and between academic appointments and board certification. Of 100 graduates, there were 57 directors, 52 certified, and 41 with academic appointments. Twenty-two graduates (11 women and 11 men) attained all three.

Evaluations of enzyme-linked immunosorbent assay procedure for determining specific Epstein-Barr virus serology and of rapid test kits for diagnosis for infectious mononucleosis.

Using the results of Epstein-Barr virus-specific immunofluorescence serology as the "gold standard," we found that the sensitivities of the five rapid test kits varied from 78 to 84% and specificities varied from 89 to 100%. Enzyme-linked immunosorbent assay-determined specific Epstein-Barr virus antibody profiles had a sensitivity and specificity of 98.6 and 95.5%, respectively.

[Diagnostic efforts for the detection of chlamydia trachomatis infections in Iceland 1982-1994.].

The results of diagnostic testing for the detection of Chlamydial infections in Iceland during the years 1982 to 1994 were reviewed. During those 13 years 123,461 laboratory tests were performed in 101,574 examinations. These examinations were positive in 14,462 instances. The first diagnostic test to be introduced was cell culture in 1982. From then on the number of examinations and the number of positive examinations increased steadily until 1988, when positive examinations reached a peak at approximately 570 cases per 100,000 inhabitants. In 1990 a sharp decline in both the total number of examinations and positive results was observed. The percentage of positive examinations declined during the study period. In 1991 and 1992 the number of examinations, the number of positive examinations and the percentage of positive examinations increased but the number of positive tests declined again in 1993. In 1994 the polymerase chain reaction assay (PCR) replaced the much less sensitive Chlamydiazyme(R) assay and the number of positive examinations rose again although the number of tests declined. The dramatic reduction in prevalence experienced in Sweden does not seem to have taken place in Iceland. In Sweden a substantial effort was made to screen asymptomatic populations. In Iceland the screening of asymptomatic patients increased from the beginning of the study period until 1988 but declined thereafter. Screening of asymptomatic populations as well as contact tracing may be important for bringing about a significant reduction of the prevalence of sexually transmitted infections caused by Chlamydia trachomatis.

The risk of acquiring Lyme disease or babesiosis from a blood transfusion.

To determine the risk of acquiring Lyme disease or babesiosis from blood transfusion, serum was collected before and 6 weeks after patients received multiple transfusions during cardiothoracic surgery and antibodies to Borrelia burgdorferi and Babesia microti were measured. Of 155 subjects, 149 received 601 total units of packed red blood cells (PRBC) and 48 received 371 total units of platelets. No patient developed clinical or serologic evidence of Lyme disease; 1 (who received 5 units of PRBC) developed clinical and serologic evidence of babesiosis. The risk of acquiring Lyme disease from a transfused unit of PRBC was 0 (95% confidence interval [CI], 0-0.5%) and from a transfused unit of platelets was 0 (95% CI, 0-0.8%); the same risks for babesiosis were 0.17% (95% CI, 0.004%-0.9%) and 0 (95% CI, 0-0.8%), respectively. The risk of acquiring either Lyme disease or babesiosis from a blood transfusion in Connecticut is very low.

Use of recombinant OspC from Borrelia burgdorferi for serodiagnosis of early Lyme disease.

Infection with Borrelia burgdorferi, the etiologic agent of Lyme disease, is associated with an early and dominant humoral response to the spirochete's 23-kDa outer surface protein C (OspC). We have cloned and expressed OspC as a fusion protein in Escherichia coli and have shown that patient serum samples react with it in an enzyme-linked immunosorbent assay (ELISA) (S. J. Padula, A. Sampieri, F. Dias, A. Szczepanski, and R. W. Ryan, Infect. Immun. 61:5097-5105, 1993). Now we have compared the detection of B. burgdorferi-specific immunoglobulin M antibodies in 74 individuals with culture-positive erythema migrans by a whole-cell ELISA, immunoblot, and the recombinant OspC (rOspC) ELISA. Seventy-six negative controls were also studied. With all of the tests, there was a statistically significant association between the duration of disease and the frequency of a positive result. With the rOspC ELISA, the predictive value of a positive test was 100% and the predictive value of a negative test was 74%. Similar results were obtained with the whole-cell ELISA and with the immunoblot using as the source of test antigen a strain of B. burgdorferi which expresses abundant levels of OspC. We conclude that the use of rOspC in an ELISA is a convenient, readily automated, and easily standardized test for the serodiagnosis of early Lyme disease.

Single dose azithromycin treatment of gonorrhea and infections caused by C. trachomatis and U. urealyticum in men.

BACKGROUND AND OBJECTIVES: Single dose regimens have advantages in the treatment of STD. Azithromycin has unique pharmacokinetics that may make single dose regimens feasible. Treatment with a single 1 g dose of azithromycin was compared to 100 mg doxycycline twice daily for seven days. STUDY DESIGN: This was a randomized third-party blinded study on 183 male patients, 176 of whom could be evaluated for efficacy. RESULTS: Chlamydia trachomatis was cultured from 148 patients, 79 receiving azithromycin and 69 receiving doxycycline. Six patients receiving azithromycin had positive cultures on follow-up, four were known to have had sexual intercourse with infected partners. Fifty-one patients had gonorrhea; 28 were treated with azithromycin and 23 with doxycycline. Neisseria gonorrhoeae was eradicated from all patients except one receiving azithromycin. He denied sexual exposure during follow-up. Sixty patients were infected with Ureaplasma urealyticum, 35 were treated with azithromycin and 25 with doxycycline. Five patients in each group had positive cultures on follow up. Three patients receiving azithromycin and two receiving doxycycline were known to have had sexual exposure during follow-up. CONCLUSION: A single dose of azithromycin showed similar effectiveness as a 7-day regimen of doxycycline.

Molecular characterization and expression of p23 (OspC) from a North American strain of Borrelia burgdorferi.

We have found that sera from patients with early stages of Lyme disease contain predominant immunoglobulin M reactivity to a major 23-kDa protein (p23) from Borrelia burgdorferi 2591 isolated in Connecticut. To characterize this immunodominant antigen, we cloned and sequenced p23 and found it to be 83% identical by nucleotide sequence and 75% identical by amino acid sequenced to pC (recently renamed OspC), an abundantly expressed protein on the outer surface of PKo, a European strain of B. burgdorferi (B. Wilske, V. Preac-Mursic, S. Jauris, A. Hofmann, I. Pradel, E. Soutschek, E.Schwab, G. Will, and G. Wanner, Infect. Immun. 61:2182-2191, 1993). In addition, immunoelectron microscopy localized p23 to the outer membrane, confirming that p23 is the strain 2591 homolog of OspC. The North American strain B31, commonly used in serologic assays for Lyme disease, does not express OspC. Northern (RNA) blot analysis detected low levels of ospC mRNA in B31, and DNA sequencing of the ospC gene from B31 revealed a 54-bp deletion in the upstream regulatory region, possibly accounting for the low transcriptional activity of ospC. The ospC coding region from B31 was cloned and antibody-reactive OspC was expressed in Escherichia coli. An immunoglobulin M enzyme-linked immunosorbent assay using recombinant OspC as the target antigen shows promise for the serodiagnosis of early stages of Lyme disease.

Use of polymerase chain reaction for laboratory diagnosis of herpes simplex virus encephalitis.

Polymerase chain reaction was used to detect herpes simplex virus (HSV) specific deoxyribonucleic acid (DNA) sequences in acute and convalescent cerebrospinal fluid (CSF) and brain tissue of a 78-year-old man and in CSF of a neonate who died of complications owing to herpes simplex virus encephalitis (HSVE). Polymerase chain reaction (PCR) was carried out for 35 cycles with a set of primers that bracketed a 92 base pair segment unique to the HSV DNA polymerase gene. Amplified DNA was electrophoresed on 3 percent agarose gel, blotted onto a nylon membrane, and probed with 32p-labeled oligonucleotide internal to the primers. The HSV specific DNA sequences were detected in the specimens from both patients. No HSV specific DNA was detected in CSFs from 20 patients with suspected Lyme disease or neurosyphilis. Polymerase chain reaction is a rapid and noninvasive technique for the diagnosis of HSVE.

Persistence of serum antibodies to Borrelia burgdorferi in patients treated for Lyme disease.

To determine if antibodies to Borrelia burgdorferi persist after antibiotic treatment, we recalled 32 patients with Lyme disease from a primary care practice a mean of 16 months after treatment and analyzed initial and follow-up serum samples by ELISA and immunoblot assays. Of the eight patients whose initial serum specimens were positive for IgM antibody by ELISA, three had positive titers of IgM antibody at follow-up; of the 23 patients whose initial serum specimens were positive for IgG antibody by ELISA, 19 had positive titers of IgG at follow-up. Of the five patients whose initial serum specimens were positive for IgM antibody by immunoblot, two had positive titers of IgM antibody at follow-up; of the 30 patients whose initial serum specimens were positive for IgG antibody by immunoblot, 29 had positive titers of IgG antibody at follow-up. The bands on the IgG immunoblot remained remarkably constant during the period from analysis of the initial specimen to that of the follow-up specimen. Nine of the 32 patients had persistent or recurrent symptoms, and ELISA and immunoblot were not helpful for identifying these nine patients.

Azithromycin in the treatment of sexually transmitted disease.

One hundred and eighty-two patients were enrolled in a randomized third-party blinded study to assess the efficacy and safety of azithromycin in the treatment of sexually transmitted diseases. Three regimens of azithromycin, including a single oral dose, were compared with a standard treatment with doxycycline. The patients were followed for four weeks. Efficacy was evaluated in 168 patients (113 azithromycin, 55 doxycycline). Fourteen patients had negative cultures or did not come for all follow-up visits. Of the 168, 138 were infected with Chlamydia trachomatis, 43 with Neisseria gonorrhoeae, and 45 with Ureaplasma urealyticum. Ninety-six per cent of patients with chlamydial infections and 92% of those with gonorrhoea were cured with azithromycin. Two patients infected with N. gonorrhoeae, four with C. trachomatis and six with U. urealyticum had positive cultures on follow-up visits after receiving azithromycin. Of these 11 patients with positive cultures on follow-up visits, seven (five with U. urealyticum and two with C. trachomatis) violated the protocol by having intercourse with infected individuals during the study. Azithromycin was very well tolerated; one patient complained of mild abdominal pain shortly after receiving the drug, seven patients complained of mild nausea and two patients had mild diarrhoea.

Comparative evaluation of three products for the detection of Borrelia burgdorferi antibody in human serum.

Eighty human serum specimens tested concomitantly by immunoblot and an enzyme-linked immunosorbent assay developed jointly at the University of Connecticut School of Medicine and the Connecticut Agricultural Experiment Station were used to evaluate three commercially available diagnostic products for Lyme borreliosis. The sources of the kits were Hillcrest Biologicals, Cypress, Calif.; Whittaker Bioproducts, Walkersville, Md.; and Cambridge Bioscience, Worcester, Mass. When compared with Western blot analysis, the sensitivities and specificities, respectively, for the diagnostic assays were as follows: Hillcrest Biologicals, 93 and 75%; Whittaker Bioproducts, 73 and 100%; Cambridge Bioscience, 89 and 100%; and University of Connecticut School of Medicine, 96 and 92%.

DNA probe versus culture for detection of Mycoplasma pneumoniae in clinical specimens.

The laboratory diagnosis of Mycoplasma pneumoniae is often difficult because of lengthy and complicated cultural methods and serological tests that may be both insensitive and nonspecific. In this study, 82 patients suspected of Mycoplasma pneumonia were cultured for M. pneumoniae, and their respiratory secretions were tested by a DNA probe for M. pneumoniae. The probe test was 100% sensitive and 98% specific compared to culture. This DNA probe, then, is an effective alternative method for the detection of M. pneumoniae in respiratory specimens.

Kell blood group activity of gram-negative bacteria.

To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens.

Asymptomatic calcified herniated thoracic disks: CT recognition.

Among 270 CT scans of the thorax obtained over a 7-month period, four patients (1.5%) with calcified herniated thoracic disks were identified. Each of these patients presented with abnormal chest radiographs and had a CT examination for evaluation of suspected malignancy. None showed any signs or symptoms of thoracic spinal cord compression. The clinical significance of incidental thoracic disk protrusions is unknown. It may be that these patients are at risk for the later development of symptomatic disk disease.

Multicenter comparative evaluation of two rapid microscopic methods and culture for detection of Chlamydia trachomatis in patient specimens.

Four hundred and seventy-three men and women at high risk for sexually transmitted disease were tested for the presence of Chlamydia trachomatis in the urethra or the endocervix. Four groups were involved in this multicenter study of two direct fluorescent-antibody microscopy tests, Kallestad Pathfinder and Syva Microtrak, compared with culture techniques. Results from the test sites indicated that there was no significant difference overall in the sensitivity and specificity of the two test kits. However, there was some interlaboratory variation seen in the sensitivity of the microscopy, but little difference in the specificity. Either kit could be an effective screening method for C. trachomatis in high-risk populations.

Comparative evaluation of three commercial tests for detection of heterophile antibody in patients with infectious mononucleosis.

Infectious mononucleosis (IM) is caused by the Epstein-Barr virus. Commonly used laboratory tests used for diagnosis of IM include a screening test based on the observation that horse erythrocytes are agglutinated by the Paul-Bunnell antibody found in the serum of patients with IM. This study evaluated two latex agglutination (LA) kits for IM, Monolatex (Wampole Laboratories) and Immunoscan-IM (American MicroScan) (formerly Monogen; Biokit, S.A.), and compared them with Monospot (Ortho Diagnostic Systems) results on 220 patient sera. Discrepancies in the three test results were resolved with complete Epstein-Barr virus antibody profiles. They indicated that any of the three kits tested can be successfully used as a screening test for IM. The advantage of the LA kits is that no differential absorption step is necessary. When discrepancies were resolved, sensitivity and specificity of both LA kits were greater than 93%.

Utility of a rapid latex test for the detection of Clostridium difficile in fecal specimens.

Currently, the method of choice for the laboratory diagnosis of Clostridium difficile disease is the detection of cytotoxin in stool filtrates by tissue culture. Since many hospital laboratories do not have tissue culture facilities, there is a need for a rapid test which is both sensitive and specific to diagnose C. difficile disease. A commercial latex agglutination was compared with the conventional cytotoxin tissue culture assay for the detection of C. difficile or its toxin(s) in fecal specimens. Of the 574 specimens evaluated, 111 were cytotoxin positive while 97 were positive by the latex agglutination test. There were 17 specimens positive by latex agglutination but negative by tissue culture assay. The overall sensitivity and specificity of the CDT latex test was 86.1 percent and 95.3 percent respectively. This rapid latex test can serve as an excellent screening procedure for the presence of C. difficile. Those specimens positive by the latex test should be further evaluated for the presence of cytotoxin by tissue culture.

Clinical and ecological characteristics of Vibrio vulnificus in the northeastern United States.

Multiple seawater sites in the northeastern United States, particularly Long Island Sound, and shellfish from Long Island Sound were sampled from April to November for 3 successive yr, 1983-1985. Hospitals in coastal and metropolitan areas of Connecticut were surveyed for the same 3-yr period, Vibrio vulnificus can be found in these waters during the summer months. The appearance of these virulent bacteria in both seawater and shellfish are a function of the water temperature; no V. vulnificus could be isolated until the temperature was approximately 17 degrees C. Although the risk of infection is small, as shown by isolation of this organism from patients, certain high-risk groups exist. Consumption of raw shell fish during the summer months should be discouraged in people with liver disease or patients on immunosuppressive therapy.