Resistance to antiviral drugs in herpes simplex virus infections among allogeneic stem cell transplant recipients: risk factors and prognostic significance.

Herpes simplex virus (HSV) infections in 75 allogeneic stem cell transplant recipients were analyzed. Sixteen patients developed HSV disease following transplantation. The risk factors were age, sex (females), unrelated donor graft, and graft-versus-host disease (GVHD) grade >/=2.

Analysis of hepatitis B virus quasispecies changes during emergence and reversion of lamivudine resistance in liver transplantation.

This report describes nucleotide sequence analysis of part of the polymerase gene of hepatitis B virus (HBV) during the development of lamivudine-resistant HBV in five patients who received lamivudine treatment in conjunction with liver transplantation. Samples from patients were analysed before, during and after drug treatment in conjunction with serum HBV quantification by PCR. Lamivudine resistance was found to be associated with L526M and M550V changes in two patients and M550I change in three patients.

Isolation of viruses from stools in stem cell transplant recipients: a prospective surveillance study.

We prospectively examined stool specimens for enteric viruses in 75 stem cell transplant recipients (autologous 48, allogeneic 27) to determine the frequency and significance of these infections. Only six patients (8%) had a positive isolate. Five of these were allograft recipients (18%) compared to one autograft recipient (2%) (P = 0.

Selection of multiresistant hepatitis B virus during sequential nucleoside-analogue therapy.

Hepatitis B virus (HBV) drug resistance to lamivudine is always accompanied by mutations in the viral polymerase gene at position 550, termed group 1 (M550V with L526M) or group 2 (M550I) mutations. The latter mutation has not been associated with famciclovir resistance. Thus, the addition of famciclovir to lamivudine therapy in persons with group 2 lamivudine resistance may lead to virus suppression.

An outbreak of neonatal infection with Acinetobacter linked to contaminated suction catheters.

An outbreak of multi-drug resistant Acinetobacter spp. infection in the neonatal unit at King Edward VIII hospital in Durban, South Africa, is described. Nine out of a total of 218 neonates were infected during the study period.

Significance testing of clinical data using virus dynamics models with a Markov chain Monte Carlo method: application to emergence of lamivudine-resistant hepatitis B virus.

Bayesian analysis using a virus dynamics model is demonstrated to facilitate hypothesis testing of patterns in clinical time-series. Our Markov chain Monte Carlo implementation demonstrates that the viraemia time-series observed in two sets of hepatitis B patients on antiviral (lamivudine) therapy, chronic carriers and liver transplant patients, are significantly different, overcoming clinical trial design differences that question the validity of non-parametric tests. We show that lamivudine-resistant mutants grow faster in transplant patients than in chronic carriers, which probably explains the differences in emergence times and failure rates between these two sets of patients.

Poor reduction of HIV-1 RNA titres in nucleoside reverse transcriptase inhibitor experienced patients treated with indinavir combination therapy.

Objectives: The long term effectiveness of combination therapy at reducing viral loads in seminal fluid and blood plasma obtained from HIV-1 infected men who had undergone previous antiretroviral therapy was assessed.

Methods: Samples of semen and blood were obtained from a cohort of 12 nucleoside reverse transcriptase inhibitor experienced men before and during 25-68 weeks of combination therapy, which included the protease inhibitor indinavir. HIV-1 RNA titres present in the cell free blood and seminal plasma samples were determined using the nucleic acid sequence based amplification (NASBA)/Nuclisens assay system.

Asymptomatic urethritis and detection of HIV-1 RNA in seminal plasma.

Objective: To define risk factors for detection of HIV-1 RNA in semen in men attending the two largest HIV clinics in the West Midlands.

Methods: 94 HIV-1 seropositive men at any stage of infection donated matched semen and blood samples. 36 subjects (38%) were on no antiretroviral treatment, 12 (13%) were on dual therapy, and 46 (49%) were on three or more drugs.

Outcome of lamivudine resistant hepatitis B virus infection in the liver transplant recipient.

Background: In many transplant centres lamivudine is an important component of prophylaxis against, and treatment of, hepatitis B virus (HBV) graft infection. Drug resistant HBV species with specific polymerase mutations may emerge during lamivudine treatment.

Aims: To examine the clinical consequences of graft infection by lamivudine resistant virus.

Urinary levels of tissue kallikrein in the South African Black and Indian hypertensives.

It is accepted that Black subjects differ from White and Indian hypertensives in their response to hypotensive agents. Black hypertensives in the USA have a lower urinary tissue kallikrein (TK) excretion levels compared to White hypertensives. It has been suggested that Black patients respond better to thiazide diuretics compared to beta-blockers because thiazides increase whereas beta-blockers decrease tissue kallikrein excretion.

Prevalence of long-term BK and JC excretion in HIV-infected adults and lack of correlation with serological markers.

The natural history of polyomavirus infection, and sensitivity of diagnostic assays remain unclear. A stratified group of 94 human immunodeficiency virus (HIV)-infected patients was studied for both virological and serological markers of active infection with both JC virus and BK virus. JC DNA was detected in the urine of 18 of 81 (22%) patients and BK DNA in 30 (37%) patients.

Respiratory viruses in adult liver transplant recipients.

Background: The contribution of respiratory viruses to respiratory disease in adult liver transplant (LT) recipients has not been studied. We performed a prospective audit to document the incidence of respiratory syncytial viruses ([RSVs], parainfluenza virus, influenza virus, and adenovirus) after LT, and to determine their contribution to respiratory disease in this setting.

Methods: Consecutive adult recipients were followed for 8 months after LT.

Use of real-time PCR and fluorimetry to detect lamivudine resistance-associated mutations in hepatitis B virus.

Very rapid amplification of DNA by PCR in small volumes can be continuously monitored by the detection of the binding of probes with a rapid cycler with built-in fluorometric detection. Primers were designed to amplify approximately 100 bp of the polymerase gene of hepatitis B virus (HBV) spanning codon 550, where mutations associated with resistance to lamivudine invariably occur. Four hybridization probes were synthesized: one was 3' labelled with fluorescein and hybridized upstream of codon 550.

Hepatic dysfunction in a population of antibody-deficient patients: prevalence, aetiology and outcome of PCR screening for hepatitis C and G viruses.

Background And Objectives: A group of 40 antibody-deficient patients receiving regular infusions of intravenous immunoglobulin underwent close monitoring in an attempt to identify hepatic dysfunction. The continuing risk of hepatitis virus transmission, especially hepatitis C virus via immunoglobulin products prompted this policy. We report our findings.

High pre-treatment serum hepatitis B virus titre predicts failure of lamivudine prophylaxis and graft re-infection after liver transplantation.

Background/aims: Orthotopic liver transplantation has an established role for the treatment of patients with chronic liver failure secondary to hepatitis B virus (HBV) infection. Unfortunately, recurrent infection of the graft can be associated with aggressive disease, and with diminished graft and patient survival. Currently, the role of nucleoside analogues for prevention of graft re-infection is being evaluated.

Laboratory surveillance of Shigella dysenteriae type 1 in KwaZulu-Natal.

Objective: To collect data on the antimicrobial susceptibility of Shigella dysenteriae type 1 in KwaZulu-Natal, including the testing of newer therapeutic agents, and to evaluate the ability of laboratories to participate in a provincial surveillance programme.

Design: Prospective descriptive study.

Setting: Hospital laboratories in KwaZulu-Natal, including peripheral laboratories and the medical microbiology laboratory of the University of Natal.

GBV-C/HGV coinfection in HIV-1-positive men: frequent detection of viral RNA in blood plasma but absence from seminal fluid plasma.

Sequential paired samples of blood and seminal fluid were obtained from a cohort of 54 HIV-1-infected homosexual males. The prevalence of GBV-C/HGV RNA in the cell-free fractions of some of these patients was determined using reverse-transcription polymerase chain reaction (RT-PCR). To assess the effects of HIV-1 and HCV infection upon GBV-C/HGV RNA status, blood CD4 cell counts, HCV RNA status, and HIV-1 proviral DNA and viral RNA titres were also determined.