BACKGROUND Treatment of cytomegalovirus (CMV) infections after stem cell transplantation (SCT) does not always lead to a rapid viral response. The causes of treatment failure may be either viral... Show moreBACKGROUND Treatment of cytomegalovirus (CMV) infections after stem cell transplantation (SCT) does not always lead to a rapid viral response. The causes of treatment failure may be either viral resistance or immunological failure to control viral replication. This study investigated the response to pre-emptive treatment in CMV infections in order to define risk factors for treatment failure, including the role of antiviral resistance. METHODS Adult recipients of allogeneic T-cell depleted SCT were studied retrospectively (n=92). CMV infections were treated with (val)ganciclovir according to a CMV DNA-load-based pre-emptive strategy. Treatment failure was defined as a CMV DNA load of 1,000 copies/ml or more after at least 2 weeks of treatment. Resistance was analysed by nucleotide sequence analysis of the UL97 and UL54 genes in the first CMV DNA-positive sample and in samples during treatment failure. RESULTS Treatment failure occurred in 26 of the 47 pre-emptively treated patients (55%) and in 39 of 86 (45%) treatment episodes. The risk of treatment failure was increased during first treatment episodes (P=0.01) and during the use of immunosuppressive medication (P=0.02). Antiviral resistance was found in only 1 patient (4%) with treatment failure. CONCLUSIONS A slow response to pre-emptive antiviral treatment occurred frequently in CMV infections in SCT recipients. Antiviral resistance was observed but played a minor role in treatment failure. Show less
BACKGROUND: Human enteroviruses (HEVs) can cause severe infections, especially in patients with a deficient humoral immune response, such as X-linked agammaglobulinemia. In this patient group,... Show moreBACKGROUND: Human enteroviruses (HEVs) can cause severe infections, especially in patients with a deficient humoral immune response, such as X-linked agammaglobulinemia. In this patient group, chronic enteroviral meningitis (CEMA) is feared because of extensive morbidity and high fatality rate. Treatment options consist of intravenous immunoglobulin (IVIG), with various outcomes. Pleconaril is an antiviral agent with in vitro activity against HEVs that has been used in the treatment of HEV infections. METHODS: The efficacy of pleconaril and IVIG against HEV isolated from the patients was assessed in vitro in two patients with CEMA. RESULTS: Echovirus 11 was found in the cerebrospinal fluid (CSF) of case 1. Treatment with high-dose IVIG and pleconaril did not provide any clinical improvement and HEV PCR in CSF remained positive. Case 2 (echovirus 13 positive in CSF) was also treated with IVIG and pleconaril. The patient recovered completely and HEV PCR in CSF became negative. Recent IVIG batches contained low titres of neutralizing antibodies against the patient strains. Echovirus 11 (case 1) was resistant to pleconaril in vitro, whereas echovirus 13 (case 2) was susceptible, in accordance with virological response after treatment and subsequent clinical results. CONCLUSIONS: This is the first report that evaluates efficacy of antiviral treatment in CEMA patients in relation to in vitro susceptibility of clinical virus isolates. Since pleconaril is no longer available for compassionate use we strongly propagate that new drugs should be developed against these potential life threatening HEV infections. Show less
Zhang, S.; Sighem, A. van; Gras, L.; Reiss, P.; Smit, C.; Kroon, F.; ... ; Wolf, F. de 2010
Background: Transient episodes of HIV type-1 viraemia are frequently observed in patients on suppressive combination antiretroviral therapy (cART). We studied the effect of such episodes and of... Show moreBackground: Transient episodes of HIV type-1 viraemia are frequently observed in patients on suppressive combination antiretroviral therapy (cART). We studied the effect of such episodes and of treatment interruptions on clinical outcome and immunological response. Methods: A total of 3,321 patients from the ATHENA cohort had virological suppression (HIV type-1 RNA<50 copies/ml) after 24 weeks of cART. The association between subsequent episodes of treatment interruptions, viral suppression, low-level (50-400 copies/ml) and high-level (>400 copies/ml) viraemia and the outcomes death, AIDS or immunological response (CD4(+) T-cell count increase >= 50% from 24 weeks) was studied with Poisson regression models, including either time-updated cumulative follow-up, time spent per type of episode or modelling episodes as binary status indicators. Results: During 11,165 person-years of follow-up, 88 patients died, 111 developed AIDS and 2,019 had an immunological response. Longer follow-up time in treatment interruptions increased the risk of AIDS (relative risk [RR] 8.07, 95% confidence interval [CI] 3.98-16.4 per year longer) and impaired immunological response (RR 0.22, 95%) CI 0.12-0.41). High-level viraemia was only associated with immunological response (RR 0.55, 95% CI 0.40-0.74), whereas low-level viraemia was not associated with any of the three outcomes. Status indicator models gave similar results. When also including time-updated CD4(+) T-cell counts, the observed associations diminished. Conclusions: Treatment interruptions and high-level, but not low-level, viraemia are strongly associated with clinical outcome, mainly via their effect on CD4(+) T-cell counts Show less
