Browsing by Subject "chlamydia"

Now showing 1 - 4 of 4
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    Immunoglobulin-Based Investigation of Spontaneous Resolution of Chlamydia trachomatis Infection
    (Oxford, 2017-06) Bakshi, Rakesh; Gupta, Kanupriya; Jordan, Stephen J.; Brown, Ladraka' T.; Press, Christen G.; Gorwitz, Rachel J.; Papp, John R.; Morrison, Sandra G.; Lee, Jeannette Y.; Morrison, Richard P.; Geisler, William M.; Medicine, School of Medicine
    Chlamydia trachomatis elementary body enzyme-linked immunosorbent assay (ELISA) was used to investigate serum anti-CT immunoglobulin G1 (IgG1; long-lived response) and immunoglobulin G3 (IgG3; short-lived response indicating more recent infection) from treatment (enrollment) and 6-month follow-up visits in 77 women previously classified as having spontaneous resolution of chlamydia. Of these women, 71.4% were IgG1+IgG3+, consistent with more recent chlamydia resolution. 15.6% were IgG3− at both visits, suggesting absence of recent chlamydia. Using elementary body ELISA, we demonstrated approximately 1 in 6 women classified as having spontaneous resolution of chlamydia might have been exposed to C. trachomatis but not infected. Further, we classified their possible infection stage.
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    Mutational Analysis of the Chlamydia muridarum Plasticity Zone
    (American Society for Microbiology, 2015-07) Rajaram, Krithika; Giebel, Amanda M.; Toh, Evelyn; Hu, Shuai; Newman, Jasmine H.; Morrison, Sandra G.; Kari, Laszlo; Morrison, Richard P.; Nelson, David E.; Department of Biology, IU School of Science
    Pathogenically diverse Chlamydia spp. can have surprisingly similar genomes. C. trachomatis isolates that cause trachoma, sexually transmitted genital tract infections (chlamydia) and invasive lymphogranuloma venereum (LGV), and the murine strain C. muridarum share 99% of their gene content. A region of high genomic diversity between Chlamydia spp. termed the Plasticity Zone (PZ) may encode niche-specific virulence determinants that dictate pathogenic diversity. We hypothesized that PZ genes might mediate the greater virulence and IFN-γ resistance of C. muridarum compared to C. trachomatis in the murine genital tract. To test this hypothesis, we isolated and characterized a series of C. muridarum PZ nonsense mutants. Strains with nonsense mutations in chlamydial cytotoxins, guaBA-add and a phospholipase D homolog developed normally in cell culture. Two of the cytotoxin mutants were less cytotoxic than wild-type suggesting that the cytotoxins may be functional. However, none of the PZ nonsense mutants exhibited increased IFN-γ sensitivity in cell culture or were profoundly attenuated in a murine genital tract infection model. Our results suggest that C. muridarum PZ genes are transcribed and some may produce functional proteins, but are dispensable for infection of the murine genital tract.
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    Validation of ICD-10-CM Codes for Identifying Cases of Chlamydia and Gonorrhea
    (Wolters Kluwer, 2020-07) Ho, Yenling A.; Rahurkar, Saurabh; Tao, Guoyu; Patel, Chirag G.; Arno, Janet N.; Wang, Jane; Broyles, Andrea A.; Dixon, Brian E.; Epidemiology, School of Public Health
    Background While researchers seek to use administrative health data to examine outcomes for individuals with sexually transmitted infections, the ICD-CM-10 codes used to identify persons with chlamydia and gonorrhea have not been validated. Objectives were to determine the validity of using ICD-10-CM codes to identify individuals with chlamydia and gonorrhea. Methods We utilized data from electronic health records gathered from public and private health systems from October 1, 2015 to December 31, 2016. Patients were included if they were aged 13-44 years and received either 1) laboratory testing for chlamydia or gonorrhea or 2) an ICD-10-CM diagnosis of chlamydia, gonorrhea, or an unspecified STI. To validate ICD-10-CM codes, we calculated positive and negative predictive values, sensitivity, and specificity based on the presence of a laboratory test result. We further examined the timing of clinical diagnosis relative to laboratory testing. Results The positive predictive values for chlamydia, gonorrhea, and unspecified STI ICD-10-CM codes were 87.6%, 85.0%, and 32.0%, respectively. Negative predictive values were high (>92%). Sensitivity for chlamydia diagnostic codes was 10.6% and gonorrhea was 9.7%. Specificity was 99.9% for both chlamydia and gonorrhea. The date of diagnosis occurred on or after the date of the laboratory result for 84.8% of persons with chlamydia, 91.9% for gonorrhea, and 23.5% for unspecified STI. Conclusions Disease specific ICD-10-CM codes accurately identify persons with chlamydia and gonorrhea. However, low sensitivities suggest that most individuals could not be identified in administrative data alone without laboratory test results.
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    Where Do People Go for Gonorrhea and Chlamydia Tests: A Cross-sectional View of the Central Indiana population, 2003-2014
    (Wolters Kluwer, 2018-10) Batteiger, Teresa A.; Dixon, Brian E.; Wang, Jane; Zhang, Zuoyi; Tao, Guoyu; Tong, Yan; Tu, Wanzhu; Hoover, Sarah A.; Arno, Janet N.; Medicine, School of Medicine
    Background Despite major efforts to control their spread, reported sexually transmitted infections (STI) are increasing. Using data from a mid-sized Midwest metropolitan area, we examined the settings in which individuals are tested for gonorrhea and chlamydia in relation to demographics and test result to determine where interventions may best be focused. Methods A de-identified and integrated registry, containing records from all patients tested for an STI from 2003-2014, was created by combining data from a large health information exchange and the reporting district’s STI Program located in Indianapolis, IN. Individual characteristics and visit settings where gonorrhea and chlamydia testing was performed were analyzed. Results We identified 298,946 individuals with 1,062,369 visits where testing occurred at least once between the ages of 13 and 44 years. Females were tested significantly more often than males and received testing more often in outpatient clinics whereas males were most often tested in the STI clinic. Individuals who utilized both STI and non-STI settings were more likely to have a positive test at an STI or ED visit (6.4% - 20.8%) than outpatient or inpatient setting (0.0-11.3%) (p<.0001). Test visits increased over the study period particularly in emergency departments, which showed a substantial increase in the number of positive test visits. Conclusions The most frequent testing sites remain STI clinics for men and outpatient clinics for women. Yet, emergency departments are increasingly a source of testing and morbidity. This makes them a valuable target for public health interventions that could improve care and population health.