CMV in the gut: a critical review of CMV detection in the immunocompetent host with colitis.

As scientific techniques for the detection of cytomegalovirus (CMV) improve, we are able to detect small amounts of CMV in the mucosal wall. As clinicians, we are unsure how to interpret the results of this novel test. There is controversy in the literature as to the significance of the detection of CMV in the gut. Whilst the importance of CMV and reactivation of the virus is clear in those patients such as allograft recipients with established immune compromise, the role is less clear in patients with less damaged immune systems. We explore whether the detection of CMV in such cases influences outcome and how it should be optimally managed. We discuss the optimal management of such cases, according to current guidelines, with a review of the literature.

Expanded blood borne virus testing in a tuberculosis clinic. A cost and yield analysis.

OBJECTIVES: Testing for HIV is a standard of care for people with active tuberculosis (TB). People investigated for TB in the UK often originate from areas with a high prevalence of HIV and other blood borne viruses (BBV). However, assessment for these infections is patchy. We determined the yield and costs of different testing strategies for BBV in a UK TB clinic. METHODS: Since 2009, it has been routine to test all TB clinic attendees. Demographic, clinical and virological data were retrospectively extracted from patient notes and hospital databases. RESULTS: Over 3 years, 1036 people were assessed in the TB service. 410 had a final diagnosis of active TB. HIV testing of the latter population diagnosed 27 new HIV cases at a cost of £3017. When BBV testing was offered to all clinic attendees, a further 6 (total 33) new HIV, 5 Hepatitis B (HBV) and 2 Hepatitis C (HCV) diagnoses were made at a total cost of £22,170. CONCLUSIONS: We have identified previously undiagnosed HIV, HBV and HCV in a TB clinic population. Our data suggest that despite increasing upfront expense, the associated yield argues strongly for BBV testing to be offered to all patients being investigated for possible TB, irrespective of their final diagnosis.

The utility of genotypic tropism testing in clinical practice.

A review of a large number of HIV-1 tropism test requests (n = 1148) performed at a London tertiary referral centre was carried out. The aim was to establish whether these were being performed in line with recommendations from published guidelines and whether this represented the most cost-effective use of these tests in informing prescribing decisions of the CCR5 antagonist drug, maraviroc. The cost of these assays within the UK was covered by commercial funding until April 2013 which has subsequently been withdrawn. Furthermore, all healthcare settings are under increasing cost constraints and hence establishing the real utility and appropriate use of these tests is of vital importance.

Positive hepatitis B virus core antibody in HIV infection--false positive or evidence of previous infection?

Isolated HBV core antibody (anti-HBc) is defined as the presence of anti-HBc with a negative HBV surface antigen (HBsAg) and HBV surface antibody (anti-HBs <10 IU/l). In patients infected with HIV with isolated anti-HBc, the aim was to determine: The prevalence of isolated positive anti-HBc; The most effective method of identifying which patients have had previous Hepatitis B Virus (HBV) infection; The prevalence of false positive anti-HBc. HBV serology results were identified from 539 patients infected with HIV sampled between January 2010 and December 2012. In those with an isolated anti-HBc and negative anti-HBe, a second anti-HBc test was carried out using a different assay. Samples were also screened for HBV DNA. The anti-retroviral regimens at time of screening were documented. 101/539 had an isolated anti-HBc. Of these, 32 (32%) had a positive anti-HBe (including 1 equivocal) and 69(68%) were anti-HBe negative. Of those negative for anti-HBe, 32 were tested for both DNA and a second anti-HBc. Of these 26 (81%) were on cART at time of HBV testing, with 25 (78%) on ART with anti-HBV activity. The prevalence of isolated anti-HBc was 19%. Only 32% were also anti-HBe positive, whereas 97% of those anti-HBe negative were positive on a second anti-HBc assay suggesting lack of utility of anti-HBe in resolving serological quandaries. One subject (3%) had a false positive anti-HBc. There was no evidence of chronic HBV but 78% patients were on HBV-suppressive combination anti-retroviral therapy.

Quantification of hepatic FOXP3+ T-lymphocytes in HIV/hepatitis C coinfection.

Coinfection with HIV adversely impacts every stage of hepatitis C (HCV) infection. Liver damage in HCV infection results from host antiviral responses rather than direct viral pathogenesis. Despite depressed cellular immunity, coinfected patients show accelerated hepatic fibrosis compared with HCV monoinfected patients. This paradox is poorly understood. T-regulatory (Treg) cells (CD4+ and FOXP3+) are hypothesized to limit hepatic damage in HCV. Our hypothesis was that reduced frequency of hepatic Treg in HIV/HCV coinfection compared with HCV monoinfection may explain poorer outcomes. We quantified FOXP3+, CD4+, CD8+ and CD20+ cells in liver biopsies of 35 male subjects matched by age and ISHAK fibrosis score, 12 HIV monoinfected, 11 HCV monoinfected and 12 HIV/HCV coinfected. Cell counts were performed using indirect immunohistochemical staining and light microscopy. HIV/HCV coinfected subjects had fewer hepatic FOXP3+ (P = 0.031) and CD4+ cells (P = 0.001) than HCV monoinfected subjects. Coinfected subjects had more hepatic CD8+ cells compared with HCV monoinfected (P = 0.023), and a lower ratio of FOXP3+ to CD8+ cells (0.08 vs 0.27, P < 0.001). Multivariate analysis showed number of CD4+ cells controlled for differences in number of FOXP3+ cells. Fewer hepatic FOXP3+ and CD4+ cells in HIV/HCV coinfection compared with HCV monoinfection suggests lower Treg activity, driven by an overall loss of CD4+ cells. Higher number of CD8+ cells in HIV/HCV coinfection suggests higher cytotoxic activity. This may explain poorer outcomes in HIV/HCV coinfected patients and suggests a potential mechanism by which highly active antiretroviral therapy may benefit these patients.

A not so simplex case of genital herpes.

We report the case of a 28-year-old, HIV-positive woman presenting with painful vesicular and ulcerating lesions in the ano-genital region caused by varicella zoster virus that appeared similar to herpes simplex infection. The case highlights that herpes zoster needs to be considered in the differential diagnosis of genital lesions, particularly in HIV-positive individuals, and the importance of virological diagnosis by PCR to direct appropriate management.

Evaluation of the Roche prototype 454 HIV-1 ultradeep sequencing drug resistance assay in a routine diagnostic laboratory.

BACKGROUND: Studies have shown that low-frequency resistance mutations can influence treatment outcome. However, the lack of a standardized high-throughput assay has precluded their detection in clinical settings. OBJECTIVE: To evaluate the performance of the Roche prototype 454 UDS HIV-1 drug resistance assay (UDS assay) in a routine diagnostic laboratory. STUDY DESIGN: 50 plasma samples, previously characterized by population sequencing and that had shown ≥1 resistance associated mutation (RAM), were retrospectively tested by the UDS assay, including 18 B and 32 non-B subtypes; viral loads between 114-1,806,407 cp/ml; drug-naive (n=27) and drug-experienced (n=23) individuals. RESULTS: The UDS assay was successful for 37/50 (74%) samples. It detected all RAMs found by population sequencing at frequencies above 20%. In addition, 39 low-frequency RAMs were exclusively detected by the UDS assay at frequencies below 20% in both drug-naïve (19/26, 73%) and drug-experienced (9/18, 50%) individuals. UDS results would lead to changes from susceptible to resistant to efavirenz (EFV) in one drug-naive individual with suboptimal response to an EFV-containing regimen and from susceptible to resistance to lamivudine (3TC) in one drug naïve subject who subsequently failed a 3TC-containing regimen and in a treatment experienced subject who had failed a 3TC-containing regimen. CONCLUSIONS: The UDS assay performed well across a wide range of subtypes and viral loads; it showed perfect agreement with population sequencing for all RAMs analyzed. In addition, the UDS assay detected additional mutations at frequencies below 20% which correlate with patients' treatment history and had in some cases important prognostic implications.

Spontaneous clearance and treatment of acute hepatitis C infection in HIV-positive men with 48 weeks of interferon-alpha and ribavirin.

Acute hepatitis C infection in the context of HIV is an emerging problem in men who have sex with men (MSM). We conducted a retrospective cohort study of MSM diagnosed with and treated for acute hepatitis C infection over 10 years. Genotype 1 was the commonest type representing 69% of cases; the spontaneous clearance rate was 20%. The overall sustained virological response (SVR) rate on an intention-to-treat basis was 83%; SVR and was 92% for those completing 48 weeks of treatment. The presence of detectable RNA at week 12 had a 100% negative predictive value for SVR. This is the largest single cohort treated with 48 weeks of interferon and ribavirin and the treatment SVR is one of the highest reported. We propose that a 48-week treatment regimen may be superior to shorter (24-week) regimens though we acknowledge the need for a randomized controlled trial.

Impact of a clonal outbreak of extended-spectrum ß-lactamase-producing Klebsiella pneumoniae in the development and evolution of bloodstream infections by K. pneumoniae and Escherichia coli: an 11 year experience in Oxfordshire, UK.

OBJECTIVES: The objectives of this study were: (i) to describe an outbreak of multidrug-resistant Klebsiella pneumoniae in our population; (ii) to identify the potential source of this outbreak by examining antibiotic resistance trends in urocultures; (iii) to evaluate the contribution of this outbreak to resistance patterns over time in the two commonest Gram-negative blood culture isolates, namely K. pneumoniae and Escherichia coli; and (iv) to assess risk factors for multidrug resistance and the impact of this resistance on mortality and length of stay. METHODS: We searched Microbiology and Patient Administration Service databases retrospectively and describe resistance trends in E. coli and K. pneumoniae bloodstream infections (BSIs) in Oxfordshire, UK, over an 11 year period. RESULTS: An outbreak of a multidrug-resistant, CTX-M-15 extended-spectrum ß-lactamase (ESBL)-producing K. pneumoniae clone was identified and shown by multilocus sequence typing to belong to a novel sequence type designated ST490. This was associated with a sporadic change in resistance rates in K. pneumoniae BSIs with rates of multidrug resistance (defined as resistance to three or more antibiotic classes) reaching 40%. A case-control study showed prior antibiotic exposure as a risk factor for infection with this organism. During the same time period, rates of ESBL-producing Klebsiella spp. isolated from urocultures increased from 0.5% to almost 6%. By contrast, the rate of multidrug resistance in E. coli rose more steadily from 0% in 2000 to 10% in 2010. CONCLUSIONS: Changes in resistance rates may be associated with outbreaks of resistant clones in K. pneumoniae. Changing resistance patterns may affect important health economic issues such as length of stay.

Hepatobiliary infections due to non-capsulated Haemophilus influenzae.

We present two cases of non-capsulated Haemophilus influenzae hepatobiliary infection and review the literature. Such cases are rare, and prior to routine immunization against H. influenzae serotype b invasive Haemophilus disease was largely caused by capsulated strains. The epidemiology of invasive Haemophilus infections has changed and the number of cases of intra-abdominal and hepatobiliary infection may be underestimated due to current microbiological processing practices.

A DNA prime-modified vaccinia virus ankara boost vaccine encoding thrombospondin-related adhesion protein but not circumsporozoite protein partially protects healthy malaria-naive adults against Plasmodium falciparum sporozoite challenge.

The safety, immunogenicity, and efficacy of DNA and modified vaccinia virus Ankara (MVA) prime-boost regimes were assessed by using either thrombospondin-related adhesion protein (TRAP) with a multiple-epitope string ME (ME-TRAP) or the circumsporozoite protein (CS) of Plasmodium falciparum. Sixteen healthy subjects who never had malaria (malaria-naive subjects) received two priming vaccinations with DNA, followed by one boosting immunization with MVA, with either ME-TRAP or CS as the antigen. Immunogenicity was assessed by ex vivo gamma interferon (IFN-gamma) enzyme-linked immunospot assay (ELISPOT) and antibody assay. Two weeks after the final vaccination, the subjects underwent P. falciparum sporozoite challenge, with six unvaccinated controls. The vaccines were well tolerated and immunogenic, with the DDM-ME TRAP regimen producing stronger ex vivo IFN-gamma ELISPOT responses than DDM-CS. One of eight subjects receiving the DDM-ME TRAP regimen was completely protected against malaria challenge, with this group as a whole showing significant delay to parasitemia compared to controls (P = 0.045). The peak ex vivo IFN-gamma ELISPOT response in this group correlated strongly with the number of days to parasitemia (P = 0.033). No protection was observed in the DDM-CS group. Prime-boost vaccination with DNA and MVA encoding ME-TRAP but not CS resulted in partial protection against P. falciparum sporozoite challenge in the present study.

Safety of recombinant fowlpox strain FP9 and modified vaccinia virus Ankara vaccines against liver-stage P. falciparum malaria in non-immune volunteers.

The ability to generate potent antigen-specific T cell responses by vaccination has been a major hurdle in vaccinology. Vaccinia virus and avipox viruses have been shown to be capable of expressing antigens in mammalian cells and can induce a protective immune response against several mammalian pathogens. We report on two such vaccine constructs, modified vaccinia virus Ankara and FP9 (an attenuated fowlpox virus) both expressing the pre-erythrocytic malaria antigen thrombospondin-related adhesion protein and a string of CD8+ epitopes (ME-TRAP). In prime-boost combinations in a mouse model MVA and FP9 are highly immunogenic and induce substantial protective efficacy. A series of human clinical trials using the recombinant MVA and FP9 malaria vaccines encoding ME-TRAP, both independently and in prime-boost combinations with or without the DNA vaccine DNA ME-TRAP, has shown them to be both immunogenic for CD8+ T cells and capable of inducing protective efficacy. We report here a detailed analysis of the safety profiles of these viral vectors and show that anti-vector antibody responses induced by the vectors are generally low to moderate. We conclude that these vectors are safe and show acceptable side effect profiles for prophylactic vaccination.

Differentiating acute appendicitis from pelvic inflammatory disease in women of childbearing age.

A retrospective study was performed to evaluate the usefulness of various historical, clinical, and laboratory findings in differentiating acute appendicitis from pelvic inflammatory disease (PID) in women of childbearing age. The records of all female patients presenting to the emergency department with abdominal pain who were found to have histologically proven appendicitis (n = 80) or PID confirmed on endocervical culture (n = 71) were reviewed. Clinically useful indicators favoring appendicitis included the presence of anorexia and the onset of pain later than day 14 of the menstrual cycle. Indicators favoring PID included a history of vaginal discharge, urinary symptoms, prior PID, tenderness outside the right lower quadrant, cervical motion tenderness, vaginal discharge on pelvic examination, and positive urinalysis. Despite these indicators, differentiating acute appendicitis from PID remains difficult.

Use of transcutaneous electrical nerve stimulation for fingertip analgesia: a pilot study.

STUDY OBJECTIVES: To determine if transcutaneous electrical nerve stimulation (TENS) can produce fingertip analgesia. DESIGN: Randomized, crossover trial. PARTICIPANTS: Fifteen healthy volunteers, naive to the technique of TENS. INTERVENTIONS: TENS stimulation was applied to the middle and ring fingers of each subject's hands by means of small carbon electrodes placed over the digital nerves. Patients received one fingertip puncture from a mechanically driven sterile lancet device to each digit corresponding to one of four conditions: sham, one minute of TENS, ten minutes of TENS, and 20 minutes of TENS. The TENS unit was operated in the "burst" mode, with two eight-pulse burst groups per second (pulse width, 225 mu sec; pulse frequency, 80 Hz). The order of the conditions and the finger used for each condition were assigned randomly. The pain of each puncture was rated on a 10-cm visual-analog scale. Data were analyzed using a repeated-measures analysis of variance with Duncan's multiple comparisons procedure. MEASUREMENTS AND RESULTS: Mean visual-analog scale scores decreased sequentially from sham in each experimental condition: one minute of TENS, 24.4% (P < .025); ten minutes of TENS, 28.2% (P < .025); and 20 minutes of TENS, 55.7% (P < 10(-6)). Two patients had total anesthesia of the fingertip (visual-analog scale = 0 cm) in the 20-minute TENS condition. CONCLUSION: TENS significantly reduces the pain of lancet-induced trauma to the fingertip. Further studies are warranted to determine if this technique is useful clinically as an alternative or adjunct to digital nerve block anesthesia for fingertip surgical procedures.