[Infection of the orbita due to Delftia acidovorans after a cat scratch]. / Orbita-Infektion mit Delftia acidovorans nach Katzenkratzer.

HISTORY: A 60 years old woman experienced a cat scratch 34 months ago on the left eyelid. Chronic, progredient skin lesions and headache developed. Treatments with cortisone, pimecrolimus, pregabalin and metamizole were not successful. After 24 months the patient complained of severe bulbus pain in the left eye, increased eye movement pain, and high photosensitivity. There were granulomatous papules in the area of the eye. FINDINGS AND DIAGNOSIS: The interdisciplinary examination findings and clinical-chemical parameters were inconspicuous. A biopsy of the eyelid area revealed the detection of Delftia acidovorans by bacterial 16S-rRNA-PCR. THERAPY AND COURSE: Treatment with piperacillin/tazobactam 3 × 4.5 g/d IV for 10 days led to rapid clinical improvement, so that the patient could be discharged after 11 days. After additional 10 months, she had no relapse and was free of complaints. CONCLUSIONS: D. acidovorans has not yet appeared as a zoonotic pathogen but should be included in the case of injury by animals in the differential diagnostic considerations.

Evolution of adefovir-resistant HBV polymerase gene variants after switching to tenofovir disoproxil fumarate monotherapy.

BACKGROUND: Tenofovir disoproxil fumarate (TDF), an acyclic nucleotide analogue was shown to be effective in many HBV-infected patients with resistance to adefovir dipivoxil (ADV). This observation is intriguing because in vitro studies show that HBV mutations selected by ADV confer cross-resistance to TDF. To assess the clinical relevance of this cross-resistance, we studied the evolution of HBV polymerase gene variants in patients with genotypic resistance against ADV (rtN236T and/or rtA181V/T) during TDF treatment. METHODS: In 10 HBV-monoinfected patients (9 male, mean age 47 ±11 [range 27-67] years, 6 hepatitis B e antigen-positive) with virological breakthrough during ADV treatment associated with the mutations rtN236T and/or rtA181T/V, HBV polymerase gene variants were studied during up to 24 months of consecutive monotherapy with TDF by population sequencing, line probe assay and clonal analysis. RESULTS: In all patients, switching to TDF resulted in a continuous reduction of HBV DNA from a median of 7.6 (4.6-9.4) log(10) copies/ml to 3.3 (2-5) log(10) copies/ml, remaining in 7 patients >400 copies/ml at 12 months. ADV-resistance mutations remained detectable throughout the whole observation period in most patients. Apart from an M204Q mutation in one sample, no new HBV polymerase gene mutations were found. In two patients with low level viraemia after 72 weeks of TDF, adding lamivudine led to a complete response within a few weeks. CONCLUSIONS: ADV-resistant HBV variants may further become selected during TDF treatment, however they cause only a mild decrease in TDF susceptibility.

Long-term efficacy of tenofovir monotherapy for hepatitis B virus-monoinfected patients after failure of nucleoside/nucleotide analogues.

UNLABELLED: Tenofovir disoproxil fumarate (TDF) has demonstrated high antiviral efficacy in treatment-naive patients with chronic hepatitis B virus (HBV) infection but experience in nucleoside/nucleotide analogue (NA)-experienced patients is limited. In this retrospective multicenter study we therefore assessed the long-term efficacy of TDF monotherapy in patients with prior failure or resistance to different NA treatments. Criteria for inclusion were HBV DNA levels >4.0 log(10) copies/mL at the start and a minimum period of TDF therapy for at least 6 months. In all, 131 patients (mean age 42 +/- 12 years, 95 male, 65% hepatitis B e antigen [HBeAg]-positive) were eligible. Pretreatment consisted of either monotherapy with lamivudine (LAM; n = 18), adefovir (ADV; n = 8), and sequential LAM-ADV therapy (n = 73), or add-on combination therapy with both drugs (n = 29). Three patients had failed entecavir therapy. Resistance analysis in 113 of the 131 patients revealed genotypic LAM and ADV resistance in 62% and 19% of patients, respectively. The mean HBV DNA level at TDF baseline was 7.6 +/- 1.5 log(10) copies/mL. The overall cumulative proportion of patients achieving HBV DNA levels <400 copies/mL was 79% after a mean treatment duration of 23 months (range, 6-60). Although LAM resistance did not influence the antiviral efficacy of TDF, the presence of ADV resistance impaired TDF efficacy (100% versus 52% probability of HBV DNA <400 copies/mL, respectively). However, virologic breakthrough was not observed in any of the patients during the entire observation period. Loss of HBeAg occurred in 24% of patients and HBsAg loss occurred in 3%. No significant adverse events were noticed during TDF monotherapy. CONCLUSION: TDF monotherapy induced a potent and long-lasting antiviral response in NA-experienced patients with previous treatment failure. Our data may have implications for current add-on strategies.

Tenofovir for patients with lamivudine-resistant hepatitis B virus (HBV) infection and high HBV DNA level during adefovir therapy.

Incomplete virological response to adefovir dipivoxil (ADV) has been observed in patients with lamivudine-resistant hepatitis B virus (HBV) infection and may be associated with developing resistance and disease progression. We therefore investigated whether the efficacy of viral suppression could be improved by replacing ADV with tenofovir disoproxil fumarate (TDF). Twenty patients with chronic HBV infection (18 HBeAg+), viral breakthrough during lamivudine therapy, and persistent viral replication (>10(4) copies/mL) after 15 months of ADV monotherapy (range 4-28 months) were treated with TDF 300 mg daily and were retrospectively analyzed. A screening for nucleoside/nucleotide analogue resistance mutations within the HBV polymerase gene was performed in all patients by direct sequencing. Within a median of 3.5 months, application of TDF led to undetectable HBV DNA in 19 of 20 patients, as demonstrated by suppression of HBV DNA below the detection limit of 400 copies/mL. Initially elevated ALT levels had normalized in 10 of 14 patients by the end of follow-up (median 12 months, range 3-24 months). Four patients lost HBeAg, after 3, 4, 5, and 16 months, and one patient seroconverted to anti-HBs after 16 months of TDF therapy. Lamivudine-associated mutations (rtV173L, rtL180M, rtM204V/I) could be detected in 6 patients at baseline of TDF, but this obviously did not influence the response. ADV-resistant mutations were not detected. No side effects were reported. In conclusion, these preliminary observations strongly suggest that TDF might be a highly effective rescue drug for HBV-infected patients with altered responsiveness to treatment with lamivudine and ADV.

Clinical reactivation after liver transplantation with an unusual minor strain of hepatitis B virus in an occult carrier.

Hepatitis B virus (HBV) DNA is detectable in a number of liver transplant candidates who are negative for hepatitis B surface antigen (HBsAg). After liver transplantation (LT), such patients may have molecular and/or serologic evidence of HBV replication. However, clinical disease from reactivation of occult HBV infection after LT has not been described. We report a patient who underwent LT for cryptogenic cirrhosis and had to be retransplanted twice for hepatic artery thrombosis. The patient was negative for HBsAg and positive for anti-hepatitis B core (HBc) and anti-HBs before all LT procedures and developed acute hepatitis B shortly after receiving the third graft. The HBV strain isolated at that time exhibited an unusual in frame insertion of a CAG motif within the HBV polymerase (HBV(INS+)). HBV(INS+) was detected retrospectively as a minor species in pretransplantation sera and the explanted native liver by insertion-specific polymerase chain reaction. This case in an occult HBV carrier shows that clinically apparent, endogenous reinfection of the graft may occur with minor HBV variants that are not detectable in pretransplantation samples by standard diagnostic procedures. This has implications for the analysis of sources of acute hepatitis B in patients after LT and possibly for consideration of antiviral prophylaxis in anti-HBc/anti-HBs/HBV DNA-positive patients.

Prolonged time until seroconversion among hemodialysis patients: the need for HCV PCR.

OBJECTIVE: Patients on maintenance hemodialysis are known to have an elevated risk of acquiring hepatitis C virus (HCV) infection. Therefore, a reliable diagnosis of HCV infection is essential in order to prevent the spread of the disease in dialysis units. However, whether PCR examination is dispensable in hemodialysis patients has been debated. METHODS: From 1995 to 2002, serum samples from all hemodialysis patients at our hospital (n = 1,774) were screened by serological assays and by polymerase chain reaction (PCR). RESULTS: In 25 of these patients acute HCV infection was observed and in 11 patients HCV seroconversion was delayed for 3-16 months. During this time the infection was exclusively detectable by PCR. CONCLUSION: Despite the growing demand for cost-effectiveness in the health system, HCV PCR examination must remain an essential part of the routine screening in hemodialysis patients.

Viral features of lamivudine resistant hepatitis B genotypes A and D.

Viral differences among lamivudine resistant hepatitis B (HBV) genotypes have not been yet investigated. Therefore, we analyzed the characteristics of these viral strains in vivo. Forty-one patients carrying lamivudine resistant HBV were enrolled. Twenty-six patients (63%) carried resistant HBV genotype A (group A) and 15 patients (37%) carried resistant HBV genotype D (group D). The rate of reverse transcriptase 204I mutants was significantly higher in group D (67%) compared with group A (19%), whereas rt204V mutants (81% in group A vs 33% in group D; P =.006) and rt180M mutants (81% in group A vs 40% in group D, P =.015) prevailed in group A. The median time of shift from rt204I to rt204V mutants was significantly shorter in group A (4 months in group A, >12 months in group D, P <.001). Additional resistance associated mutations were detected exclusively in group D (P =.004). In a multivariate analysis, HBV genotype (P =.039) and pretreatment serum HBV DNA (P =.001) were independently associated with emerging rt204I or rt204V mutants, respectively. Serum HBV copy numbers after emergence of resistance were higher in group A (mean log(10) 6.99 copies/ml; range 3-9) compared with group D (mean log(10) 6.1 copies/ml; range 3.3-8; P =.04). There was no difference between both groups regarding core promoter/precore mutations, viral turnover, and number of flares or disease progression during follow-up. In conclusion, the mutational pattern during selection of lamivudine resistant HBV strains differs between genotypes A and D. This may have consequences for a salvage regimen initiated for treatment of lamivudine resistant HBV.

Multiple infections with different HCV genotypes: prevalence and clinical impact.

BACKGROUND: In a HCV genotype 3a-infected patient, viremia with a different genotype (1b) was detected after 16 weeks of ineffective therapy. Serological typing revealed that this genotype had already been present prior to therapy. OBJECTIVES: To investigate the epidemiology of multiple HCV infections and the therapeutical consequences for patients superinfected with a new HCV strain. METHODS: Sera of 600 patients were screened for infection with multiple genotypes by using sequencing and a serological assay in parallel. RESULTS: Infection with two different HCV types was detected in 13 patients. The prevailing strain was genotyped by sequencing. From two of these patients additional sera were available which had been drawn up to 24 and 28 months prior to the current sample, respectively. Those early samples showed viremia with a HCV subtype that could not be detected by PCR afterwards. Only antibodies to the initial strain were detectable in the later samples. CONCLUSION: In patients serially infected by different HCV strains, one strain will prevail as the viremic virus. Under antiviral therapy, the displaced strain may become viremic again and may influence the outcome of therapy. Detection of inferior strains by serological assays before antiviral therapy may be important for choosing the adequate regimen.

A novel DNA virus (SEN) among patients on maintenance hemodialysis: prevalence and clinical importance.

BACKGROUND: A recently discovered DNA virus (SEN) has been assumed to be responsible for posttransfusion hepatitis in humans. Phylogenetic analysis of SEN virus has revealed the existence of 8 different strains. Two of them (SEN virus strain H (SENV-H) and SENV-D) have been described as possible candidate viruses for inducing posttransfusion hepatitis. Until now, it is unclear whether patients on maintenance hemodialysis are on increased risk for acquiring SEN virus. OBJECTIVES: To investigate the prevalence of SENV-H among patients on maintenance hemodialysis and to examine whether special measures have to be taken to prevent nosocomial spreading of the virus. STUDY DESIGN: Serum samples derived from 78 chronically hemodialysed patients were examined for SENV-H viremia by seminested polymerase chain reaction. A panel of 226 samples from healthy blood donors served as a control group. RESULTS: The prevalence of SENV-H was determined to be 12.8% (n=10) among patients on maintenance hemodialysis. This is nearly the same prevalence as in healthy blood donors (16.8%; n=38). None of the solely SENV-H-viremic individuals had clinical or biochemical signs of liver disease. Enhanced severity of liver disease could not be observed in patients coinfected with hepatitis C virus and SENV-H. CONCLUSION: We conclude that SENV-H viremia is widespread among hemodialysis patients. Since no viremic patient had clinical or biochemical signs of liver disease, in our setting the hepatitis-inducing capacity of SENV-H remains unclear. On the basis of our results, at present, we do not regard it as necessary to dialyse SENV-H-viremic patients on separate machines.

Comparison of BDPhoenix and VITEK2 automated antimicrobial susceptibility test systems for extended-spectrum beta-lactamase detection in Escherichia coli and Klebsiella species clinical isolates.

The present study compares the ability to detect extended-spectrum beta-lactamases (ESBL) among a collection of 34 ESBL producing clinical isolates belonging to Escherichia coli and Klebsiella species with two new rapid susceptibility and identification instruments-VITEK2 (bioMérieux, Marcy l'Etoile, France) vs. BDPhoenix (BD Biosciences, Sparks, MD). ESBL content in these isolates was previously characterized on the basis of PCR amplification and sequencing results which were used as the reference method in our evaluation. BDPhoenix correctly determined the ESBL outcome for all strains tested (100% detection rate), whereas VITEK2 was not able to detect the ESBL status in 5 isolates (85% detection rate). Detailed analysis revealed that the discrepancies were mainly observed with 'difficult-to-detect' strains. Misidentification was either due to low oximino cephalosporin MIC in these strains or was associated with pronounced 'cefotaximase' or 'ceftazidimase' phenotypes. Klebsiella oxytoca chromosomal beta-lactamase (K1) is phenotypically quite similar to ESBL enzymes. In order to evaluate whether the K1 and ESBL enzymes could be discriminated, we expanded our analysis by 8 clinical K. oxytoca strains with K1 phenotypes. VITEK2 gave excellent identification of these strains whereas 7 out of 8 were falsely labeled ESBL-positive by the BDPhoenix system.

Epidemiological dynamics of hepatitis C virus among 747 German individuals: new subtypes on the advance.

This study demonstrates the dynamics in the epidemiology of hepatitis C virus subtypes. Subtypes 3a and 4a have become increasingly prevalent in patients where an infection within recent years can be assumed. Evidence is presented that the subtypes observed among younger patients can spread rapidly and lead to significant changes in the subtype distribution.

Genotyping of hepatitis C virus types 1, 2, 3, and 4 by a one-step LightCycler method using three different pairs of hybridization probes.

Determination of hepatitis C virus (HCV) genotypes has become increasingly important during the last years for prediction of the clinical course and the outcome of antiviral therapy. Therefore, numerous different methods have been developed to enable HCV genotyping. However, many of them are very laborious and expensive, leading to limited usage in daily routine diagnostics. We have established a method which combines the speed of the new LightCycler technology with the use of amplification products generated for diagnostic quantitative HCV RNA determination. Differentiation of HCV genotypes is performed with these amplicons in a single step by using fluorophore-labeled hybridization probes. Although currently only two different acceptor fluorophores are available for the LightCycler, types 1, 2, 3, and 4, which are by far the prevailing HCV genotypes in Europe and the United States, can be distinguished. Genotypes of specimens from 190 chronically HCV-infected patients were determined by the LightCycler method and compared with the results of nucleotide sequencing. Concordant results were obtained for all samples. This new method offers a fast and convenient possibility to determine the quantitative HCV RNA load and the genotype in large-scale settings within about 4 h.

Subtype-dependent response of hepatitis B virus during the early phase of lamivudine treatment.

We conducted a 12-month longitudinal investigation of the subtype-dependent response of hepatitis B virus (HBV) to lamivudine treatment in 43 consecutive patients with chronic hepatitis B. HBV subtype ayw appears to respond better to lamivudine monotherapy than does HBV subtype adw (P=.005). This might be the reason for the lower incidence of lamivudine-resistant strains observed in persons infected with HBV subtype ayw during follow-up.

Reappearance of HIV multidrug-resistance in plasma and circulating lymphocytes after reintroduction of antiretroviral therapy.

BACKGROUND: After the discontinuation of antiretroviral therapy in HIV-infected patients with highly resistant virus, the detectability of viral resistance mutations quickly decreases. To which extent this represents a true loss of resistance or rather a detectability phenomenon remains unclear. OBJECTIVES: To monitor virologic response and resistance pattern during a non-strategic treatment interruption in the presence of highly drug-resistant viral strains. STUDY DESIGN: We performed serial genotypic resistance analyses on viral DNA isolated from a patient with a multidrug-resistant human immunodeficiency virus infection who discontinued and later on reintroduced antiretroviral therapy. Sequencing was performed on viral DNA from plasma as well as DNA from circulating leukocytes. RESULTS: While under combination antiretroviral therapy with two nucleosidic reverse transcriptase inhibitors, a non-nucleosidic reverse transcriptase inhibitor and a protease inhibitor, the viral load of the patient was around five logs. Genotypic resistance to all available agents was detected during this time. Antiretroviral therapy was then interrupted, and 14 weeks later an almost complete reversion of the virus to wild type was observed. After introduction of a new antiretroviral therapy regimen, the reappearance of nearly all of the formerly present resistance mutations had to be noted within 6 weeks, including mutations without known relation to any of the drugs in the new regimen. CONCLUSIONS: We obviously observed not the de novo appearance of a complex resistance pattern under just 6 weeks of potent antiretroviral therapy, but a reappearing archival strain of the virus. This finding provides evidence for subdetectable persistence of resistant variants during treatment interruptions. Therefore, resistance analyses from peripheral blood performed in times of treatment interruptions should be interpreted with caution as they may provide incomplete information about the resistance profile soon after reintroduction of therapy.