Replacement of calcineurin inhibitors with daclizumab in patients with transplantation-associated microangiopathy or renal insufficiency associated with graft-versus-host disease

Transplantation-associated microangiopathy (TAM) or renal insufficiency (RI) after allogeneic hematopoietic stem cell transplantation is associated with a high mortality. As calcineurin inhibitors (CI) may contribute to TAM or RI, we evaluated the efficacy of replacing CI by daclizumab in patients with graft-versus-host disease (GVHD). Thirteen patients with GVHD-associated TAM and five patients with RI were treated with daclizumab 1 mg/kg intravenous (i.v.)/week, discontinuation of the CI and continuation of the remaining GVHD treatment. All patients had acute GVHD (steroid-sensitive (n=4), steroid-refractory (n=10)) or chronic GVHD (n=4) and were treated with CI before the start of daclizumab. Nine of 13 patients with TAM treated with daclizumab and discontinuation of CI achieved complete remission of TAM, two had stable disease, and one patient did not respond. Patients receiving daclizumab for RI without TAM showed stabilization (2/5) or improvement (3/5) of renal function. Four of 14 patients with acute GVHD achieved CR, two partial remission, eight patients did not respond and 11/14 died at a median of 39 days after start of the daclizumab. Our data demonstrate that replacement of CI by daclizumab can improve TAM and RI. However, mortality remains high in patients with acute GVHD.

Monitoring of the JAK2-V617F mutation by highly sensitive quantitative real-time PCR after allogeneic stem cell transplantation in patients with myelofibrosis

The JAK2-V617F mutation occurs in about 50% of patients with myelofibrosis and might be a reliable marker to monitor residual disease after allogeneic stem cell transplantation. We describe a new, highly sensitive (>or= 0.01%) real-time polymerase chain reaction (PCR) to monitor and quantify V617F-JAK2-positive cells after dose-reduced allogeneic stem cell transplantation. After 22 allogeneic stem cell transplantation procedures in 21 JAK2-positive patients with myelofibrosis, 78% became PCR negative. In 15 of 17 patients (88%), JAK2 remained negative after a median follow-up of 20 months. JAK2 negativity was achieved after a median of 89 days after allograft (range, 19-750 days). A significant inverse correlation was seen for JAK2 positivity and donor-cell chimerism (r:-0.91, P<.001). Four of 5 patients who never achieved JAK2 negativity fulfilled during the entire follow-up all criteria for complete remission recently proposed by the International Working Group, suggesting a major role for JAK2 measurement to determine depths of remission. In one case, residual JAK2-positive cells were successfully eliminated by donor lymphocyte infusion. In conclusion, allogeneic stem cell transplantation after dose-reduced conditioning induces high rates of molecular remission in JAK2-positive patients with myelofibrosis, and quantification of V617F-JAK2 mutation by real-time PCR allows the detection of minimal residual disease to guide adoptive immunotherapy.

Monocyte-derived cells express CYP27A1 and convert vitamin D3 into its active metabolite

CYP27A1 catalyses hydroxylations in the biosynthesis of bile acids and the bioactivation of vitamin D3. We investigated the expression of CYP27A1 in human monocytes, monocyte-derived macrophages, and dendritic cells on mRNA and protein levels as well as its enzymatic activity in comparison with the expression of CYP27B1 and CYP24A1. Macrophages showed a strong expression of CYP27A1, whereas monocytes and dendritic cells expressed low levels of CYP27A1 mRNA. Immunohistochemistry revealed CYP27A1 and CYP27B1 protein expression in macrophages. Accordingly, macrophages converted vitamin D3 into the active metabolite 1,25(OH)2D3. Dendritic cells also metabolized vitamin D3 although to a lesser extent. This could be due to the high expression of CYP24A1, the enzyme that degrades 25(OH)D3 and 1,25(OH)2D3. Our results show that macrophages and dendritic cells are capable to perform both hydroxylation steps of the vitamin D3 metabolism suggesting a possible role of local 1,25(OH)2D3 synthesis by myeloid cells in the skin and gut.

Prognostic significance of NOD2/CARD15 variants in HLA-identical sibling hematopoietic stem cell transplantation: effect on long-term outcome is confirmed in 2 independent cohorts and may be modulated by the type of gastrointestinal decontamination

To assess the role of NOD2/CARD15 variants on the long-term outcome of allogeneic stem cell transplantation in a genetically homogeneous group, we extended our previous study (cohort I, n = 78) and typed DNA for NOD2/CARD15 single nucleotide polymorphisms (SNPs) from an additional 225 recipients and their HLA-identical sibling donors (cohort II) treated at four other European centers. Results of genotyping were compared with clinical outcome. The strong association of NOD2/CARD15 variants with transplantation-related mortality (TRM) was confirmed in univariate and multivariate analysis; TRM increased from 20% in cohort I/22% in cohort II in recipient/donor pairs without any NOD2/CARD15 variants to 47% in cohort I/32% in cohort II in the presence of one variant in either donor or recipient and further to 57% in cohort I/74% in cohort II in the presence of 2 or more variants (P < .002 in both cohorts). NOD2/CARD15 SNPs were not associated with relapse rate but had a strong impact on overall survival. In an analysis of center effects, the type of gastrointestinal decontamination was the only factor interfering with the prognostic significance of NOD2/CARD15 SNPs. Our data further support an interaction between gastrointestinal defense mechanisms, activation of the innate immune system, and specific transplant-related complications.

Exposure of hematologic patients to parvovirus B19 as a contaminant of blood cell preparations and blood products

BACKGROUND

Patients with hematologic malignancies often require blood products, and parvovirus B19 is known to be transmitted by this route. Primary infection with parvovirus B19 shows a wide variety of disease manifestation. In immunocompromised patients, symptoms are severe and viral clearance is delayed or missing.

STUDY DESIGN AND METHODS

A total of 2123 blood products given to all patients of a hematologic ward over a period of 6 months were retrospectively examined for the presence of parvovirus B19 DNA by an in-house real-time polymerase chain reaction (PCR; TaqMan). Patients who had received B19 DNA-positive blood products were further investigated serologically and by PCR for the presence of parvovirus B19 antibodies and DNA.

RESULTS

Twenty-one (1%) of 2123 blood products tested positive for the presence of B19 DNA (2% of pooled products, 0.7% of single-donor products, and 17.6% of allogeneic peripheral blood progenitor cells), the median viral load was 700 genome equivalents per mL. During the study period, 114 patients were treated on the ward, and 14 (12%) of them received B19 DNA-positive blood components. None of them developed symptoms of an acute B19 infection, although one had a short low-level viremia.

CONCLUSIONS

Although B19 DNA was detected in 1 percent of blood products given to hematologic patients, the exposure of 12 percent of patients did not result in symptomatic infections.

Reactivation of resolved hepatitis B virus infection after allogeneic haematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT) is well known in HBsAg-positive carriers but has only occasionally been reported in patients with resolved HBV infection. We investigated six allo-HSCT recipients with pretransplant anti-HBs and anti-HBc antibodies for serologic markers of HBV infection and for the presence of HBV-DNA in serum. Reverse seroconversion, that is, reappearance of HBsAg after a gradual loss of anti-HBs, but no severe liver damage was observed in three patients at 14, 22 and 12 months after HSCT, respectively. There was an increase in HBV-DNA concentration prior to reverse seroconversion. One patient was repeatedly HBV-DNA positive (10(2)-10(3) copies/ml) without reverse seroconversion. Sequencing of the HBsAg and precore region derived from the four HBV-DNA-positive patients showed no relevant mutations. In conclusion, this study demonstrated a high risk (50%) of reverse seroconversion in allo-HSCT recipients with resolved HBV infection. A highly sensitive HBV-DNA assay (TaqMan-PCR) allowed early identification of the individual patients at risk.

Reactivation of resolved hepatitis B virus infection after allogeneic haematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT) is well known in HBsAg-positive carriers but has only occasionally been reported in patients with resolved HBV infection. We investigated six allo-HSCT recipients with pretransplant anti-HBs and anti-HBc antibodies for serologic markers of HBV infection and for the presence of HBV-DNA in serum. Reverse seroconversion, that is, reappearance of HBsAg after a gradual loss of anti-HBs, but no severe liver damage was observed in three patients at 14, 22 and 12 months after HSCT, respectively. There was an increase in HBV-DNA concentration prior to reverse seroconversion. One patient was repeatedly HBV-DNA positive (10(2)-10(3) copies/ml) without reverse seroconversion. Sequencing of the HBsAg and precore region derived from the four HBV-DNA-positive patients showed no relevant mutations. In conclusion, this study demonstrated a high risk (50%) of reverse seroconversion in allo-HSCT recipients with resolved HBV infection. A highly sensitive HBV-DNA assay (TaqMan-PCR) allowed early identification of the individual patients at risk.

Quantitation of Epstein-Barr virus mRNA using reverse transcription and real-time PCR

Monitoring of Epstein-Barr virus (EBV) infection and reactivation in immunocompromized patients (e.g., after organ or bone-marrow transplantation) is based mainly on serological assays and detection of viral DNA. For further characterization of virus reactivation and monitoring of viral transcription we established real-time RT-PCR assays using TaqMan technology to sensitively quantify viral transcripts expressed at different times of the lytic cycle: for BZLF1, an immediate early transactivator initiating the transition from latency to lytic replication, for the DNA-polymerase BALF5 and for the major viral glycoprotein gp350/220 (BLLF1). RNA-isolation was optimized to eliminate contaminating DNA. Preparations were shown to be virtually DNA-free for up to 10(6) copies of RNA. With our PCR systems, it is possible to detect 10 copies of DNA or 100 copies of RNA per reaction as shown with serial dilutions of DNA-plasmids or in vitro transcribed RNA, respectively. This corresponds to a detection limit of 8 x 10(2) copies/10(6) peripheral blood mononuclear cells (PBMCs). Evaluation of this system showed that even in healthy carriers borderline levels of BLLF1 mRNA were sometimes detectable. In patients with acute infectious mononucleosis (IM) viral transcripts were regularly found in varying concentrations. Extremely high levels of all three mRNA species could be seen in a patient after bone-marrow transplantation monitored during an episode of lymphoproliferation which regressed during treatment with acyclovir and transfusion of donor T-cells. This sensitive and reproducible method to detect and quantify different transcripts of EBV can be used to closely monitor reactivation of EBV, e.g., in immunocompromized patients.

Long-term parvovirus B19 viraemia associated with pure red cell aplasia after allogeneic bone marrow transplantation

BACKGROUND

Parvovirus B19 infection is associated with a variety of symptoms like erythema infectiosum, anaemia and arthritis. In immunocompetent persons, viraemia is usually cleared a few weeks after infection.

OBJECTIVE

An immunocompromised adult female patient was persistently infected with B19 after allogenic bone marrow transplantation (BMT) and developed chronic anaemia.

STUDY DESIGN

B19-specific antibodies were determined by ELISA and viral load was assessed using a quantitative real time B19 PCR. The patient was evaluated clinically.

RESULTS

Two years after successful BMT, the patient received intensified immunosuppressive treatment, erythropoetin and erythrocyte concentrates due to chronic graft-versus-host disease with renal failure. Despite of this treatment, the aplastic anaemia worsened. PCR revealed B19 viraemia with 10(12) geq/ml serum. After 7 months of repeated applications of immunoglobulins and reduction of immunosuppressive treatment, reticulocyte counts and haemoglobin levels normalized and the viral load finally dropped to 10(3) geq/ml serum. One of the back-up samples of the erythrocyte concentrates tested positive, the respective transfusion had been applied 2 months after the beginning of viraemia.

CONCLUSIONS

The source of the primary infection remained unclear, but at least re-infection by blood transfusion is likely. Treatment did not result in virus elimination from peripheral blood but in resolvement of symptoms.

[Neuropathological findings after cardiac surgery-retrospective study over 6 years]

Neuropathologische Untersuchungen sollen dazu beitragen, die Ursachen der zentralnervösen Komplikationen nach Herzoperationen aufzudecken und die Rate der postoperativen neurologisch-kognitiven Störungen zu reduzieren. Unter diesem Aspekt haben wir die Gehirne von 262 nach herzchirurgischen Operationen (Bypass-, Klappenoperationen und Herztransplantationen) Verstorbenen untersucht. Es finden sich Zirkulationsstörungen (Makro- und Mikroblutungen, Infarkte, Subarachnoidalblutungen, hypoxämische Hirnschäden) in 128 Fällen (49%), davon kommen 33 Fälle als Todesursache in Betracht (12,6%). Als Ursachen der Infarkte sind neben einer stenosierenden Arteriosklerose von Hirnarterien und Thromboembolien (Operationsgebiet, Myokardinfarkte) in seltenen Fällen Fettembolien (2), Fremdkörperembolien (1) und Mikroembolien durch Megakaryozyten zu nennen. Weiterhin bestehen entzündliche Veränderungen in 17 Fällen, davon meist Septikopyämien (12 Fälle) durch Pilze oder Bakterien, und in 5 Fällen ließen sich Gliaknötchen als mögliches Substrat einer viralen oder Autoimmunencephalitis (Bickerstaff) nachweisen. Als Nebenbefund fand sich noch ein Morbus Alzheimer (37 Fälle, 14% des Materials) bei älteren Patienten, zum Teil mit einer Amyloidangiopatie, jedoch nicht als Todesursache und nicht als Ursache größerer Hirnblutungen. Da die Arbeit eine Autopsiestudie darstellt, ist eine Übertragung der gefundenen Veränderungen auf die Gesamtgruppe der operierten Herzpatienten mit neurologisch-kognitiven Störungen nur bedingt möglich ist. Auf jeden Fall spielen im eigenen Material umfangreiche mikroembolische Ereignisse (Fettembolie, Fremdkörperembolie), wie sie oft in der Literatur angegeben werden, keine entscheidende Rolle. Es finden sich aber, in unterschiedlicher Häufigkeit in den einzelnen untersuchten Operationsgruppen, besonders nach Klappenoperationen, Mikroblutungen der weißen Substanz, die nicht zum Tode führen. Sie könnten, ebenso wie die gelegentlich auftretenden Gliaknötchen, nach Resorption und Vernarbung postoperativ bei den Patienten neurologisch- kognitive Störungen verursachen.

Both donor and recipient NOD2/CARD15 mutations associate with transplant-related mortality and GvHD following allogeneic stem cell transplantation

Single nucleotide polymorphisms (SNPs) of the NOD2/CARD15 gene resulting in a diminished nuclear factor-kappaB (NF-kappaB) response to bacterial cell wall products have been associated with an increased incidence of Crohn disease. To assess a possible contribution of NOD2/CARD15 mutations to graft-versus-host disease (GvHD) and complications following allogeneic stem cell transplantation, we retrospectively typed DNA from donor/recipient pairs in 169 consecutive patients receiving transplants from related or unrelated donors. Mutated alleles were observed in 21% of patients and in 14% of donors. Cumulative incidence of 1-year, transplant-related mortality rose from 20% in donor/recipient pairs without mutated SNPs to 49% in pairs with recipient mutations (P =.03) and 59% in pairs with donor mutations (P <.005), and was highest in 12 pairs with mutated alleles in both donor and recipients (83%; P <.001). Similar associations were observed for severe overall and severe gastrointestinal GvHD. The impact of NOD2/CARD15 mutations was more prominent for HLA-identical sibling transplantations but was also observed in unrelated donor transplantation. Mutations proved to be independent risk factors for transplant-related mortality. Our findings indicate a major role of monocyte/macrophage dysfunction in the pathophysiology of GvHD and strongly suggest a future risk assessment or even donor selection through NOD2/CARD15 typing.

Septicemia due to Acinetobacter junii

Acinetobacter spp. are considered to be emerging nosocomial pathogens. Acinetobacter junii is a rare cause of disease in humans and was associated mainly with bacteremia in preterm infants and pediatric oncologic patients. In this report we describe a case of catheter-related infection by A. junii in an adult oncologic patient. Application of molecular methods for precise species identification of Acinetobacter spp. will help to further clarify their role as human pathogens.