CD8 encephalitis with CSF EBV viraemia and HIV drug resistance, a case series.

INTRODUCTION: CD8 encephalitis is a relatively recently described condition in the setting of HIV infection. It is becoming increasingly recognised in recent years though is still likely underdiagnosed. METHODS: We present three cases of encephalitis in HIV-positive black African females initially presenting with neurological pathology. Two cases concern recent presentations of patients attending HIV services at a large tertiary referral hospital and the third case involves a retrospective analysis of an archived case. RESULTS AND DISCUSSION: MRI brain demonstrated periventricular white matter changes in 2 cases and a cerebellar lesion in the third case. CSF examination revealed lymphocytosis and elevated protein levels. CSF HIV viral load analysis showed viral escape along with new antiretroviral drug resistance mutations. CSF flow cytometry studies demonstrated a reversed CD4:CD8 ratio with a high CD8+ cells percentage. All patients had EBV DNA detected in their CSF. Brain biopsy in two patients confirmed CD8 encephalitis and also revealed isolated cells demonstrating EBV positivity by in-situ hybridization using EBER (Epstein-Barr virus-encoded small RNAs). Treatment with steroids and ART optimisation led to significant clinical and radiological improvements in all cases. DISCUSSION: CD8 encephalitis should be considered as a cause of neurological symptoms and confusion in the HIV-positive patient, particularly if poor ART adherence or viral resistance are suspected. Brain biopsy should be considered in HIV-positive patients with encephalopathy of uncertain cause. Early treatment with high-dose corticosteroids when suspecting this diagnosis is essential for a favourable outcome. The prognosis is variable but can be favourable even following severe encephalopathy. The presence of new INSTI mutations in the CSF but absent peripherally in two INSTI-era patients is a novel finding for this case series in the context of CD8 encephalitis. The role played by EBV in this disease remains unclear and warrants further investigation.

Abacavir usage patterns and hypersensitivity reactions in the EuroSIDA cohort.

OBJECTIVES: Five to eight per cent of HIV-positive individuals initiating abacavir (ABC) experience potentially fatal hypersensitivity reactions (HSRs). We sought to describe the proportion of individuals initiating ABC and to describe the incidence and factors associated with HSR among those prescribed ABC. METHODS: We calculated the proportion of EuroSIDA individuals receiving ABC-based combination antiretroviral therapy (cART) among those receiving cART after 1 January 2009. Poisson regression was used to identify demographic, and current clinical and laboratory factors associated with ABC utilization and discontinuation. RESULTS: Between 2009 and 2016, of 10 076 individuals receiving cART, 3472 (34%) had ever received ABC-based cART. Temporal trends of ABC utilization were also heterogeneous, with 28% using ABC in 2009, dropping to 26% in 2010 and increasing to 31% in 2016, and varied across regions and over time. Poisson models showed lower ABC utilization in older individuals, and in those with higher CD4 cell counts, higher cART lines, and prior AIDS. Higher ABC utilization was associated with higher HIV RNA and poor renal function, and was more common in Central-East and Eastern Europe and lowest during 2014. During 779 person-years of follow-up (PYFU) in 2139 individuals starting ABC after 1 January 2009, 113 discontinued ABC within 6 weeks of initiation for any reason [incidence rate (IR) 14.5 (95% confidence interval (CI) 12.1, 17.5) per 100 PYFU], 13 because of reported HSR [IR 0.3 (95% CI 0.1, 1.0) per 100 PYFU] and 35 because of reported HSR/any toxicity [IR 4.5 (95% CI 3.2, 6.3) per 100 PYFU]. There were no factors significantly associated with ABC discontinuation because of reported HSR/any toxicity. CONCLUSIONS: ABC remains commonly used across Europe and the incidence of discontinuation because of reported HSR was low in our study population.

Promoting high standards of care for women living with HIV: position statement from the Women Against Viruses in Europe Working Group.

OBJECTIVES: Gender-related factors can influence management decisions, treatment outcomes and the overall long-term wellbeing of people living with HIV (PLWH). The Women Against Viruses in Europe (WAVE) Working Group was established to promote the health and wellbeing of women living with HIV (WLWH). WAVE is part of the European AIDS Clinical Society (EACS) and organizes annual workshops to discuss different issues in the management of WLWH. METHODS: In 2016, 34 WAVE members including community representatives, HIV clinicians and researchers met to discuss standards of care for WLWH and to review current guidelines. Participants focused on three different themes: (1) access to and engagement and retention in care; (2) monitoring of women on antiretroviral therapy and management of comorbidities; and (3) review of EACS treatment guidelines. RESULTS: Five priority areas for optimizing the care of WLWH were identified: (1) psychosocial aspects of HIV diagnosis and care; (2) mental health and wellbeing; (3) pharmacokinetics, toxicity and tolerability of antiretroviral therapy; (4) coinfections and comorbidities; and (5) sexual and reproductive health. WAVE recommendations are provided for each of these areas, and gaps in knowledge and needs for changes in currently existing standards are discussed. CONCLUSIONS: This position statement provides an overview of the key recommendations to optimize the care of WLWH that emerged during the 2016 WAVE workshop.

Effect of integrating HIV and addiction care for non-engaging HIV-infected opiate-dependent patients.

BACKGROUND: HIV-positive substance dependent patients contribute disproportionally to HIV morbidity and mortality as a result of poor compliance with their HIV treatment. For HIV-positive opiate-dependent patients integrating HIV and addiction care improves HIV morbidity but the effect on addiction morbidity is not known. AIMS: This study aims to establish if integrating HIV and addiction care has a significant effect on addiction and HIV morbidity for non-engaging HIV-positive opiate-dependent patients. METHODS: Patients attending the National Drug Treatment Centre who had disengaged from their HIV treatment in St James's Hospital were recruited to receive HIV care integrated into their methadone maintenance programme. Outcome was investigated in terms of urine toxicology (opiates, cocaine, cannabis and amphetamines); adherence to methadone; proportion receiving directly observed antiretroviral therapy; proportion HIV virally suppressed; and the CD4 cell count. RESULTS: No significant change in substance use or methadone adherence was demonstrated in the 19 recruited participants. There was a significant increase in the proportion receiving directly observed antiretroviral therapy, and in the CD4 cell count. CONCLUSION: Integration of HIV and addiction care optimises the physical health of non-engaging HIV-positive opiate-dependent patients with no substantial effect on their methadone maintenance programme.

Patients Accessing Ambulatory Care for HIV-infection: Epidemiology and Prevalence Assessment.

This study describes the demographics and treatment status of HIV-infected adults accessing ambulatory care in the Republic of Ireland and estimates diagnosed HIV prevalence rates. 3254 HIV-infected adults attended 1 of the 6 specialist HIV centres in the 12- month period 1st July 2009 to 30th June 2010. 2023/3254 (62%) were male, 1761/3133 (56%) Irish and 1048/3133 (34%) African. 1924/3098 (62%) resided in the Dublin area. The mean age was 39.8 years (SD 9.3); probable route of acquisition was available for 2898/3254 (89%); heterosexual acquisition accounted for 1442 (50%), MSM 777 (27%) and IDU 598 (21%). 2574/3202 (80%) were on highly active antiretroviral therapy (HAART). Of these 87% had HIV-RNA levels < 50cpm and 94% < 500cpm. The HIV diagnosed prevalence rate is estimated at 1.09/1000 nationally and at 2.25/1000 in the Dublin area for 15-59 year olds.

Clinical and epidemiological characteristics of patients with early syphilis from three academic centres in Poland, Germany and Ireland: initial findings from the POETS study.

OBJECTIVES: Syphilis recognition in HIV-positive patients has important implications. Initial data from this study, established in June 2012 to better understand the natural history of syphilis and treatment response, examine the characteristics of patients including sexual behaviour, rates of concurrent sexually transmitted infections (STI) and type of treatment given. METHODS: Patients were recruited from Ireland, Poland and Germany. Data gathered included demographics, method of syphilis acquisition, stage of syphilis infection, HIV status, nadir and current CD4 counts and HIV viral suppression rates. Data were then subanalysed into HIV-positive and HIV-negative groups. RESULTS: Of 175 patients recruited, 68% were HIV-positive and 86.3% were men who have sex with men. Most HIV-positive patients presented with secondary syphilis (55.7% vs 13.2%) (p=0.0001) while the majority of HIV-negative patients had primary syphilis noted at the time of recruitment (47.2% vs18.9%, p=0.0002). Approximately half of all patients had a HIV RNA viral load <40 copies/mL (55%). Previous syphilis infection occurred more frequently in HIV-positive than HIV-negative patients (p=0.0001). Concurrent STIs at the time of syphilis diagnosis were found in 26.8%, of whom 31 (25.4%) were HIV-positive (p=0.64). HIV-positive patients received doxycycline more frequently than their HIV-negative counterparts (33.6% vs 1.9%, p=0.0001) while HIV-negative patients were treated with long-acting penicillin in 88.7% of cases vs 58% of HIV-positive patients (p=0.0002). CONCLUSIONS: A 40% rate of unsuppressed viraemia, high levels of STIs and varying treatment regimens represent a public health risk for Europe, suggesting the model of sexual healthcare delivery in HIV-positive patients requires further evaluation.

Circulating CD56dim natural killer cells and CD56+ T cells that produce interferon-γ or interleukin-10 are expanded in asymptomatic, E antigen-negative patients with persistent hepatitis B virus infection.

Infection with hepatitis B virus (HBV) can result in spontaneous resolution or chronic infection, which can remain asymptomatic or can progress to cirrhosis and/or hepatocellular carcinoma. The host immune response is thought to be a major determinant of the outcome of HBV infection and virus-specific cytotoxic T lymphocytes (CTL) can mediate immunity against the virus and cause liver pathology. Antigen-nonspecific innate lymphocytes may also contribute to HBV infection and liver disease, therefore, we examined the frequencies, phenotypes, cytolytic activities and cytokine profiles of circulating natural killer (NK) cells, CD1d-restricted invariant natural killer T (iNKT) cells and CD56(+) T cells in 102 asymptomatic HBV-infected patients and compared them with those in 66 uninfected control subjects. NK cells expressing low levels of CD56 (CD56(dim)) and CD56(+) T cells were significantly expanded in the circulation of HBV-infected patients compared with control subjects. CD1d expression and iNKT cell frequencies were similar in both groups. Despite these expansions, we did not detect augmented natural or cytokine-induced cytotoxicity in the HBV-infected subjects. All lymphocyte populations studied produced interferon-γ (IFN-γ) significantly more frequently when taken from HBV-infected patients compared with when taken from healthy controls. Additionally, NK cells from the patients more frequently produced interleukin-10. As our HBV-infected cohort consisted of asymptomatic patients with low viral loads, we propose that CD56(dim) NK cells and CD56(+) T cells control HBV infection by noncytolytic mechanisms.

Clinically significant extra-cardiac findings in asymptomatic HIV-positive men undergoing cardiac magnetic resonance imaging.

Increased research-based imaging has led to an increase in clinically significant extra-cardiac findings. HIV patients are at increased risk of having polypathology at a younger age; therefore, it may be hypothesised that they would have more incidental findings on imaging. We reviewed the magnetic resonance imaging results of 169 HIV-positive and 40 HIV-negative, clinically well volunteers undergoing cardiac magnetic resonance imaging scanning to assess the prevalence of subclinical cardiac pathology. This sub-study assessed the prevalence of clinically significant extra-cardiac findings. Associated risk factors were assessed and clinical follow-up and outcome were ascertained. Of the HIV-positive study group, 12/169 (7.1%) vs. 1/40 (2.5%) control patients had a clinically significant extra-cardiac finding which warranted further radiological or clinical intervention (p = 0.28). A total of three out of 169 (1.1%) were highly clinically significant findings. On logistic regression analysis, age was the only significant contributing factor (p = 0.049); no HIV-associated factors were found to be significant. The prevalence of clinically significant extra-cardiac findings of 7.1% in this HIV-positive cohort is comparable to the prevalence found in previous studies carried out on an older, sicker general population. This highlights the need for planning for unexpected outcomes and also the high rate of clinically significant findings in a seemingly well HIV-positive population.

Differential interactions of antiretroviral agents with LXR, ER and GR nuclear receptors: potential contributing factors to adverse events.

BACKGROUND AND PURPOSE: Antiretroviral (ARV) drugs activate pregnane X receptors and constitutive androstane receptors, increasing the risk of drug interactions due to altered drug metabolism and disposition. The closely related liver X receptors (LXRα/ß), oestrogen receptors (ERα/ß) and glucocorticoid receptor (GR) regulate many endogenous processes such as lipid/cholesterol homeostasis, cellular differentiation and inflammation. However, ARV drug activation of these nuclear receptors has not been thoroughly investigated. EXPERIMENTAL APPROACH: The ability of an ARV drug library to activate LXRα/ß, ERα/ß and GR was assessed using a combined in silico and in vitro approach encompassing computational docking and molecular descriptor filtering, cell-free time-resolved fluorescence resonance energy transfer co-activator assays to assess direct binding to ligand-binding domains (LBDs), cell-based reporter assays and target gene expression. KEY RESULTS: Direct LBD interactions with LXRα and/or LXRß were predicted in silico and confirmed in vitro for darunavir, efavirenz, flavopiridol, maraviroc and tipranavir. Likewise, efavirenz was also predicted and confirmed as a ligand of ERα-LBD. Interestingly, atazanavir and ritonavir also activated LXRα/ß in reporter assays, while tipranavir enhanced transcriptional activity of ERα. Effects on ER and LXR target gene expression were confirmed for efavirenz and tipranavir. CONCLUSIONS AND IMPLICATIONS: There was good agreement between in silico predictions and in vitro results. However, some nuclear receptor interactions identified in vitro were probably due to allosteric effects or nuclear receptor cross-talk, rather than direct LBD binding. This study indicates that some of the adverse effects associated with ARV use may be mediated through 'off-target' effects involving nuclear receptor activation.

Health-related quality of life of HIV-infected intravenous drug users.

To investigate health-related quality of life in HIV-infected intravenous drug users registered but not engaged in HIV outpatient care (missing ≥2 outpatient appointments over 1 year or non-attendance for ≥6 months) we conducted a cross-sectional study to examine health-related quality of life of HIV-infected intravenous drug users registered for care at an inner city HIV unit. EQ-5D, SF-36, SF-6D, mood disorder, clinical and substance misuse data were collected. Mean scores and preference derived utility scores were calculated. Statistical relationships between health-related quality of life and other variables were explored using univariate and multivariate analysis. Fifty-five patients were recruited, 64% were males. The mean anxiety value was 11.44 (anxious) and mean depression score was 9.3 (borderline depressed). The mean EQ-5D utility was 0.45 (95% CI 0.35, 0.55) and mean SF-6D utility was 0.52 (95% CI 0.48, 0.55). There was no statistical relationship between HIV indices, substance misuse and EQ-5D and SF-6D utility. Anxiety and depression were significantly correlated with EQ-5D and SF-6D utility values on univariate and multivariate analysis. Health-related quality of life was reduced in this HIV-infected intravenous drug user population. Whilst hepatitis C co-infection and substance misuse did not affect health-related quality of life, anxiety and depression had a significant impact on it.

Use of the Alcohol Use Disorders Identification Test (AUDIT) to determine the prevalence of alcohol misuse among HIV-infected individuals.

The aim of the paper is to evaluate alcohol misuse among an inner city adult HIV clinic population with AUDIT (Alcohol Use Disorders Identification Test). A cross-sectional HIV outpatient clinic analysis between 28 February 2011 and 11 March 2011 was carried out. AUDIT, demographic and clinical data were collected. Univariate analysis was performed to look for the associations between variables. Backward stepwise multivariate analyses were performed on significant variables from the univariate analysis to assess for predictors of alcohol dependence. In total, 111 patients were included (60% uptake of clinic attendees); 66% were men and 26% were hepatitis C virus (HCV) co-infected. The median AUDIT score was 5 (within normal range). Thirty-four 'AUDIT positive' cases were identified: five (4.5%) indicated consumption of hazardous levels of alcohol; 21 (19%) indicated harmful levels of alcohol; and eight (7%) were likely alcohol dependent. Younger age (<40 years old) was significantly associated with AUDIT positivity (P = 0.006). On multivariate analysis younger age (P = 0.045, odds ratio 13.8) and lower level of education (P = 0.006, odds ratio 6.7) were predictive of scores indicative of alcohol dependence (AUDIT ≥20). In conclusion, younger age and lower educational levels were associated with scores consistent with alcohol dependence. AUDIT was well tolerated and easy to administer in this outpatient HIV clinic population.

Dilemmas in the management of syphilis.

A recent U.S. survey demonstrated wide variation in the management of syphilis. 25/31 (73.5%) Consultants and Specialist Registrars in Infectious Diseases and Genitourinary Medicine, in Ireland were surveyed. 23 (92%) treat more than 50 HIV patients a year, 18 (72%) had been consulted on a patient with syphilis in the last year. With secondary syphilis, 13 (52%) give 3 doses of benzathine penicillin, while 10 (40%) give one, no statistical difference between consultants and SpRs (p = 0.9). Significant variation in the investigation and management of syphilis in Ireland was identified. There is a need for the development of Irish national guidelines on the management of syphilis.

Long-term neurological follow-up of HIV-positive patients diagnosed with syphilis.

No cerebrospinal fluid (CSF) abnormalities are found in HIV-positive patients in long-term follow-up after standard syphilis treatment. Syphilis has been reported to have immunological effects on HIV infection and HIV is known to modulate both the manifestations of syphilis and the serological response to therapy. HIV-positive patients who had been diagnosed with and treated for syphilis prior to 2007 were identified. Patients were consented for lumbar puncture. Serum HIV viral load, CD4 count and CSF were recorded. Thirty-five patients with previously diagnosed and treated syphilis underwent lumbar puncture. Thirty-four patients had a normal neurological exam. Only one patient had an abnormal mean white cell count (10.7 cells per high-power field). The finding that those with previously diagnosed syphilis had normal CSF and clinical findings is reassuring and supports the practice of using standard syphilis therapy in HIV-positive patients.

Bilateral brachial neuritis secondary to varicella reactivation in an HIV-positive man.

We present the case of a 48-year-old HIV-positive man, who developed acute onset of pain in both upper limbs associated with proximal weakness and distal paraesthesia. Eight weeks prior to this presentation he had had varicella zoster affecting his right S1 dermatome. CD4 count was 355 cells/mm(3) and he was antiretroviral therapy (ART) naive. Power was 0/5 proximally and 4/5 distally in the upper limbs. Reflexes were absent and there was sensory loss in the C5, C6 and T1 dermatomes. Cerebrospinal fluid (CSF) examination showed a lymphocytosis with low glucose; however, CSF Mycobacterium tuberculosis (TB), and herpes simplex virus polymerase chain reaction (HSV PCR) were negative as was syphilis serology. Electromyography showed marked motor axonal loss. Magnetic resonance imaging (MRI) did not show any cervical spinal lesion. Varicella zoster virus (VZV) PCR was positive in the CSF. He was treated with high-dose intravenous aciclovir with good resolution of his syndrome over time and was commenced on ART. We believe this to be the first case report of varicella reactivation causing bilateral neuralgic amyotrophy in an HIV-positive patient.

Efficacy, adherence and tolerability of once daily tenofovir DF-containing antiretroviral therapy in former injecting drug users with HIV-1 receiving opiate treatment: results of a 48-week open-label study.

OBJECTIVE: To assess efficacy, adherence and tolerability of once daily antiretroviral therapy containing tenofovir disoproxil fumarate (DF) 300 mg in HIV-1-infected former injecting drug users receiving opiate treatment (IVDU). METHODS: European, 48-week, open-label, single-arm, multicenter study. Patients were either antiretroviral therapy-naive, restarting therapy after treatment discontinuation without prior virological failure or switching from existing stable treatment. RESULTS: Sixty-seven patients were enrolled in the study and 41 patients completed treatment. In the primary analysis (intent-to-treat missing=failure) at week 48, 34% of patients (23/67; 95% CI: 23%-47%) had plasma HIV-1 RNA <50 copies/mL. Using an intent-to-treat missing=excluded approach, the week 48 proportion of patients with plasma HIV-1 RNA <50 copies/mL increased to 56% (23/41; 95% CI: 40%-72%). Mean (standard deviation) increase from baseline in CD4+ cell count at week 48 was 176 (242) cells/mm(3). Although self-reported adherence appeared high, there were high levels of missing data and adherence results should be treated with caution. No new safety issues were identified. CONCLUSIONS: Levels of missing data were high in this difficult-to-treat population, but potent antiretroviral suppression was achieved in a substantial proportion of HIV-infected IVDU-patients.

High uptake of hepatitis C virus treatment in HIV/hepatitis C virus co-infected patients attending an integrated HIV/hepatitis C virus clinic.

Hepatitis C virus (HCV) is a major cause of liver disease in HIV-infected patients. The HCV treatment outcomes and barriers to HCV referral were examined in a centre with a HIV/HCV co-infection clinic. Patients who were antibody positive for both HIV and HCV between 1987 and January 2009 were identified. A retrospective chart review was undertaken. Multivariate analysis was performed to assess predictors of HCV clinic referral. Data were collected on 386 HIV/HCV patients; 202/386 had been referred to the co-infection clinic and 107/202 had HCV treatment. In addition, 29/202 were undergoing pretreatment work-up. Overall sustained virologic response (SVR) was 44%; SVR was equivalent in those who acquired HIV/HCV infection from intravenous drug use (IDU) and others. On multivariate analysis, patients who missed appointments, were younger, with active IDU and advanced HIV and who were not offered HCV treatment were less likely to be referred to the clinic. Patients attending the clinic were more likely to have been screened for hepatocellular carcinoma than those attending the general HIV service. Two-thirds of patients referred to the clinic had engaged with the HCV treatment programme. Dedicated co-infection clinics lower the threshold for treatment and improve management of liver disease in co-infected patients.

Syphilis resurgence in Dublin, Ireland.

A large outbreak of syphilis was reported in Dublin, Ireland, in 2001. The mean age of patients in 2001 was 35 years and 22.5% of patients were HIV-positive. The number of new cases decreased from 2003 on, however, new diagnoses have again increased. All positive syphilis serology results from 2007-09 were identified. Patients were included if they had a newly positive syphilis serology or, in the case of patients with previously treated syphilis, had a four-fold rise in rapid plasma reagin titre. Four hundred and thirty-nine new diagnoses of syphilis were made. The mean age of patients at diagnosis was 35.7 years (range 17-73 years). Four hundred and twelve (93.8%) cases occurred in men. Three hundred and eighty-one (86.8%) cases occurred in men who have sex with men (MSM). The estimated crude incidence rate among MSM is 378.16 per 100,000 population. Where known, 126/421 (28.7%) occurred in HIV-positive patients. Sixty-eight (15.5%) episodes of syphilis infection were diagnosed in patients who had had previously been diagnosed and treated for syphilis; 43/68 (63.2%) cases of re-infection occurred in HIV-positive patients. The rising number of syphilis diagnoses and high associated HIV co-infection rate is concerning and prevention efforts must continue to decrease the number of new syphilis cases.

HIV-related malignancies pre- and post-highly active antiretroviral therapy: experiences in an inner city tertiary referral centre.

With highly active antiretroviral therapy (HAART), AIDS-defining malignancies are becoming less common. The outcomes with standard chemotherapy are improving. In the last 10 years there have been significant changes in our patient demographics due to immigration. The aim of this study was to review the demographics and outcomes of patients with cancer in the post-HAART era and to assess the impact of changing demographics and HAART through comparing them with previously published pre-HAART data from the same centre. A retrospective chart review of 42 patients diagnosed with malignancy from 2000 to 2007 was performed and compared with pre-HAART (1987-1994) data. The incidence of malignancies has decreased from 5.2% to 2.4%. The incidence of Kaposi's sarcoma and primary cerebral lymphoma has decreased. Non-Hodgkin's lymphoma incidence has remained stable, but survival has improved with 44% of patients achieving remission. Non-AIDS-defining malignancies have increased and were associated with longer duration of HIV infection. The change in patient demographics did not have an impact on the type of malignancies diagnosed. Overall the incidence of malignancy has decreased; however, the increase in non-AIDS-defining malignancies highlights the importance of early diagnosis, use of HAART and prospective surveillance.

Role of rapid virological response in prediction of sustained virological response to Peg-IFN plus ribavirin in HCV / HIV co-infected individuals.

The objective of the study was to evaluate the role of rapid virological response (RVR) in predicting sustained virological response (SVR) rates to hepatitis C virus (HCV) therapy. 65 HIV / HCV co-infected patients commenced HCV treatment per protocol. HIV / HCV patients with a mean CD4 count of 502 were treated for 24-48 weeks depending on genotype. Virological response was assessed at weeks 4 (RVR), 12 [early virological response (EVR)], 24, at end of treatment (EOTR) and 24 weeks post-completion of treatment (SVR). Primary end-point was defined as undetectable HCV RNA at 24 weeks post-treatment completion. Fifty-five per cent of co-infected patients were on highly active anti-retroviral therapy. A majority of patient group were male. 60% of HIV / HCV patients achieved SVR (35% genotype 1 / 4; 77% genotype 2 / 3). 24 HIV / HCV patients achieved undetectable HCV levels compared with baseline by week 4. The positive predictive value (PPV) of RVR at week 4 for subsequent SVR in HIV-HCV co-infected patients was 100%; the negative predictive value (NPV) was 57%. Significant variables associated with SVR were: (i) lower median pre-treatment HCV viral load, (ii) genotype 2 / 3 disease and (iii) achievement of RVR. Independent variables associated with RVR were low pre-treatment HCV viral load and genotype 2 / 3 disease. Achievement of RVR, a negative HCV-PCR, at week 4 of treatment is predictive of SVR in this cohort of patients. This may be used to guide optimal treatment duration in patient groups. More significantly, the data serve to highlight the subgroup of patients who, on achieving RVR, should be actively supported to complete HCV treatment with full dose therapy, especially patients co-infected with G2 / 3 disease for whom 6 months' full dose therapy may be sufficient to obtain a SVR.