Goura Kudesia

Prospective comparative study of culture specimens and methods in diagnosing influenza in adults

Influenza is diagnosed by culturing influenza virus in respiratory secretions.1 Although childhood infection with respiratory syncytial virus is detected by culturing nasopharyngeal aspirates, in adults with influenza throat swabs are generally taken. This report compares culture of nasopharyngeal aspirates with culture of throat swabs and rapid culture methods with standard methods in detecting influenza virus. Between November 1995 and January 1996, 41 patients were admitted to the Infectious Disease Unit at the Royal Hallamshire Hospital, Sheffield, with symptoms and signs consistent with influenza. Thirty nine of these patients gave their informed consent to undergo nasopharyngeal aspiration in addition to routine investigations. The procedure was performed with a small suction catheter and trap. Viral transport medium was added to the aspirate and samples were sent to the laboratory within 24 hours. Nasopharyngeal aspirates and throat swabs were cultured …

The prevalence of Chlamydia trachomatis infection in male undergraduates: a postal survey.

Objectives: To determine the prevalence of Chlamydia trachomatis infection in male undergraduates and to investigate whether prevalence increases with time spent at university. To investigate the feasibility of screening men for C trachomatis by self sampling and posting of urine specimens. Methods: The study design was a postal survey undertaken by the Department of Genito-Urinary Medicine (GUM) and Student University Health Service (SUHS) in Sheffield. 2607 male undergraduates from the SUHS patient list were invited to participate in the study by providing a first void urine specimen and posting it to the laboratory. The main outcome measure was the detection of C trachomatis infection. Results: 758 students participated in the study, a response rate of 29.1%. Nine students (1.2%) tested positive for C trachomatis. The prevalence of infection in the first, second, and third year of study was 0.7%, 1.5%, and 1.6% of participants respectively. There was no statistically significant difference in prevalence of infection between first and third year students (χ2 test, p = 0.32). However, students with chlamydia had a higher median age (Mann-Whitney U test, p=<0.05). Contact tracing identified four further cases of C trachomatis infection. Conclusion: Screening for C trachomatis infection by postal survey is feasible. However, the response rate in this study was poor and the estimated sample size was not reached. Therefore, it has not been possible to determine the true prevalence of infection in this population or to accurately assess changes in prevalence with time spent at university.

BD ProbeTec ET assay for the diagnosis of gonorrhoea in a high-risk population: a protocol for replacing traditional microscopy and culture techniques

Objectives: To evaluate the Neisseria gonorrhoeae Becton Dickinson (BD) ProbeTec strand displacement assay (SDA) on female endocervical swab and male first void urine against culture for Neisseria gonorrhoeae on female endocervical and urethral swab for the diagnosis of N gonorrhoeae infection in genitourinary medicine (GUM) attendees. To determine an algorithm for implementation of N gonorrhoeae infection screening by SDA in these patients taking account of the desirability of having a N gonorrhoeae isolate in people with N gonorrhoeae infection. Methods: Initially, 1582 patients attending the GUM clinic were tested for N gonorrhoeae infection by SDA and routine microscopy, and culture. On the basis of the results, a protocol for diagnosis of N gonorrhoeae infection by SDA, with culture specimens only from patients with a listed risk factor for acquiring N gonorrhoeae infection, was devised and implemented. A post implementation audit was done to assess the effectiveness of this protocol for routine service use. Results: There was good concurrence between the N gonorrhoeae SDA and culture results with a N gonorrhoeae infection prevalence rate of 3.4% by both methods. All men and 85% of women with N gonorrhoeae infection had an identifiable risk factor for acquiring infection. Overall, 38% men and 60% women attending the GUM clinic had this listed risk factor for acquiring N gonorrhoeae. Post implementation audit confirmed the initial findings. Conclusion: Nucleic acid amplification techniques like the SDA are sensitive and specific for diagnosis of N gonorrhoeae. We were able to list certain risk factors, which were predictive of those patients most likely to have N gonorrhoeae infection. To obtain timely sensitivity data, a culture specimen should also be submitted at the same time from patients deemed to have a listed risk factor for acquiring Neisseria gonorrhoeae infection.

Prolonged cryptosporidiosis during primary HIV infection

Primary infection with the human immunodeficiency virus causes profound immunosuppression with a decrease in lymphocyte numbers and function. However, this immunosuppression is transient and most individuals regain normal immune function. Infection with opportunist pathogens during the period of immunosuppression is rare. We report a case of severe prolonged cryptosporidiosis complicating primary HIV infection. This has not previously been described. A review of other cases of opportunist infections in primary HIV infection suggests that various pathogens may take advantage of the transient immunosuppression. This has important implications for the diagnosis and management of acute HIV infection, and for the diagnostic criteria currently used for AIDS.

Management of herpesvirus infections.

Management of human herpesviruses remains a considerable clinical challenge, in part due to their ability to cause both lytic and latent disease. Infection with the Herpesviridae results in lifelong infection, which can reactivate at any time. Control of herpesviruses is by the innate and adaptive immune systems. Herpesviruses must evade the host innate immune system to establish infection. Once infected, the adaptive immune response, primarily CD8(+) T-cells, is crucial in establishing and maintaining latency. Latent herpesviruses are characterised by the presence of viral DNA in infected cells and limited or no viral replication. These characteristics provide a challenge to clinicians and those developing antiviral agents. The scope of this review is two-fold. First, to provide an overview of all antivirals used against herpesviruses, including their mechanism of action, pharmacokinetics, side effects, resistance and clinical uses. And second, to address the management of each of the eight herpesviruses both in the immunocompetent and immunocompromised host, providing evidence for clinical management and therapeutic options, which is important to the clinician engaged in the management of these infections.

Hepatitis B: Report of prevalence and access to healthcare among Chinese residents in Sheffield UK

UNLABELLED Overall prevalence of hepatitis B (HBV) in the UK is low. However, among migrants from endemic areas, prevalence has been shown to be high. Furthermore, timely diagnosis and/or referral are required prevent serious health consequences through early institution of treatment. METHODS We identified locations that would be familiar to Chinese members of the community with the objective of facilitating testing. Dried blood spot samples were collected from 229 Chinese subjects and tested for HBV and also for hepatitis C virus (HCV) infection--offering complete chronic viral hepatitis screening. RESULTS HBsAg was positive in 20/229 (8.7%) participants, (10 F, 10 M). Five women and one man were aware of their condition, but only one man and none of the women were under specialist care. The average length of residence in the UK for positive patients was 15 years (range 2-40). Evidence of HBV past infection, HBcAb(+)/HBsAg(-), was seen in 28/229 participants (12.2%). HCV antibody testing produced negative results in all participants. The methodology of testing was well accepted, 139/144 (95%) responded to a feedback questionnaire declaring no discomfort and 100% finding the information session useful. CONCLUSION This model of outreach testing is helpful for addressing health inequalities afflicting the UKs Chinese community.

Significance of low positive scores obtained with a method other than acceleration in the BDProbeTec-Strand displacement amplification test for detection of Neisseria gonorrhoeae.

Bacterial culture is the reference standard for the diagnosis of Neisseria gonorrhoeae infection and provides useful data on antimicrobial susceptibility. Strict transport and growth conditions, as well as a 48-hour bacterial growth time, can limit the sensitivity and value of culture. Nucleic acid