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C Helg

Publications and source records attributed to C Helg.

At least 19 recordsLinked to original sources
PubMed2006

Long-term complete responses after 131I-tositumomab therapy for relapsed or refractory indolent non-Hodgkin's lymphoma.

We present the long-term results of 18 chemotherapy relapsed indolent (N = 12) or transformed (N = 6) NHL patients of a phase II anti-CD20 (131)I-tositumomab (Bexxar) therapy study. The biphasic therapy included two injections of 450 mg unlabelled antibody combined with (131)I-tositumomab once as dosimetric and once as therapeutic activity delivering 75 or 65 cGy whole-body radiation dose to patients with normal or reduced platelet counts, respectively. Two patients were not treated due to disease progression during dosimetry. The overall response rate was 81% in the 16 patients treated, including 50% CR/CRu and 31% PR. Median progression free survival of the 16 patients was 22.5 months. Median overall survival has not been reached after a median observation of 48 months. Median PFS of complete responders (CR/CRu) has not been reached and will be greater than 51 months. Short-term side effects were mainly haematological and transient. Among the relevant long-term side effects, one patient previously treated with CHOP chemotherapy died from secondary myelodysplasia. Four patients developed HAMA. In conclusion, (131)I-tositumomab RIT demonstrated durable responses especially in those patients who achieved a complete response. Six of eight CR/CRu are ongoing after 46-70 months.

Adult↗
PubMed2006

Impact of high-resolution matching in allogeneic unrelated donor stem cell transplantation in Switzerland.

It is currently unknown what degree of human leukocyte antigen (HLA)-mismatching is acceptable in unrelated donor hematopoietic stem cell transplantation (UD-HSCT). Mismatches at some loci may be more permissive than others. We have analyzed the effect of high-resolution HLA-matching on outcome of all 214 consecutive recipients of UD-HSCT carried out in Switzerland. All typing was by the Swiss reference laboratory. Donor-recipient pairs were HLA-10/10 matched (n=130) or mismatched for either HLA-A/-B/-DRB1/multiple loci (n=33; (HLA-A/-B=10); (-DRB1=8); (multiple=15)); HLA-C (n=29) or HLA-DQ/-DRB3 (n=22; (DQ=16); (-DRB1=6)). The median follow-up was 32 months. Survival probabilities (+/-95% confidence interval) at 3 years were 57 (+/-10)% for recipients of HLA 10/10-matched transplants, 53 (+/-22)% for recipients of HLA-DQ/-DRB3-mismatched transplants, 44 (+/-20)% for recipients of HLA-C-mismatched transplants and 0% for recipients of transplants mismatched at HLA-A/-B/-DRB1/multiple loci (P<0.0001). In multivariate analyses, HLA compatibility was the variable most significantly associated with survival and treatment-related mortality. We found important differences in survival in recipients of UD-HSCT with best results for transplants from 10/10 matched donors. Single mismatches at HLA-DQ/-DRB3 were well tolerated, mismatches at HLA-C had intermediate results and mismatches at HLA-A/-B/-DRB1/multiple loci resulted in poor survival.

Adolescent↗
PubMed2005

Longitudinal follow-up of body composition in hematopoietic stem cell transplant patients.

Patients with hematological malignancies are well nourished prior to allogeneic hematopoietic stem cell transplantation (HSCT). HSCT and associated complications can affect body composition. The study evaluated cross-sectionally the prevalence and longitudinally the changes in lean body mass index (LBMI) in HSCT patients. Patients (n=82) were classified as normal or low LBMI. Logistic regression analyses were used to estimate odds ratios (OR) for low vs normal LBMI, between healthy volunteers and patients; for limited or extensive vs no chronic graft-versus-host-disease (GVHD); and for decreased (Karnofsky <80) vs normal functional status (>80). Patients were significantly more likely to have low LBMI at 6, 12 months, 2-3, 4-6 and >6 years than volunteers. In all, 38% of patients were below pre-HSCT LBMI at 4-6 years post-HSCT. Low LBMI was significantly associated with steroid treatment (OR 2.6, confidence intervals (CI) 1.3-5.2, P=0.008); limited (OR 5.5, CI 1.7-18.5, P=0.005) or extensive chronic GVHD (OR 20.3, CI 5.7-71.6, P<0.001); and decreased performance status (Karnofsky scores of < or =80) (OR 2.7, CI 1.3-5.9, P=0.01). Patients were more likely to have low LBMI than volunteers. Chronic GVHD and low performance status were associated with low LBMI; thus, complications and/or treatment increase the likelihood of low LBMI.

Body Composition↗
PubMed2004

Isolated HLA-C mismatches in unrelated donor transplantation for CML.

HLA-incompatibility is a major factor associated with outcome of allogeneic stem cell transplantation, but little is known on the impact of isolated HLA-C mismatches. We analyzed the outcome of 114 CML patients transplanted with marrow from unrelated donors of whom 24 were mismatched for HLA-C only (9/10 match). Univariate estimates of 5-year survival (SRV) (median follow-up: 47 months) in the HLA-matched group were 68+/-12 vs 42+/-20% (P=0.03) for the patients mismatched for HLA-C only and 33+/-33% in the mismatched group (non-HLA-C single mismatches and multiple mismatches) (P=0.0004). Disease stage, GVHD-prophylaxis (T-cell depletion), CMV-status and HLA-incompatibility were the risk factors associated (all P< or =0.005) with poor outcome. In the multivariate analysis, patients mismatched for loci other than HLA-C were at high risk of an adverse outcome (death: RR, 2.9; CI, 1.6-5.4, P=0.008, transplant-related mortality (TRM): RR, 3; CI, 1.5-5.9, P=0.0015). For patients mismatched for HLA-C only, the increased risk was of borderline significance (death: RR, 1.9; CI, 1-3.9, P=0.06, TRM: RR, 2.1; CI, 1-4.5, P=0.07). In spite of their lower expression, HLA-C antigens still represent relevant transplantation barriers that should be considered when searching for an unrelated donor.

Adult↗
PubMed2004

Resistant pure red cell aplasia after allogeneic stem cell transplantation with major ABO mismatch treated by escalating dose donor leukocyte infusion.

We report a case of pure red cell aplasia (PRCA) following allogeneic stem cell transplantation (SCT) with major ABO mismatch which proved resistant to all standard treatment options such as change in immunosuppressive treatment, high-dose erythropoietin (EPO) or plasma exchange. We therefore proceeded to administer five cycles of Rituximab therapy, without success. Finally, escalating doses of donor-derived leukocyte infusion (DLI) resolved the PRCA of our patient 415 d after bone-marrow transplantation (BMT) and 140 d after the first infusion of donor leukocytes. A review of the literature shows the efficacy of various treatments; the role of DLI and other treatment options are discussed. Furthermore, the underlying pathophysiological mechanisms especially with regard to the role of NK cells in alloreactivity after allogeneic SCT are explained.

ABO Blood-Group System↗
PubMed2003

An unusual form of primary systemic amyloidosis: amyloid elastosis: report of a case treated by haematopoietic cell transplantation.

Amyloid elastosis is a rare variant of primary systemic amyloidosis characterized by amyloid deposited around elastic fibres. Only two cases, with pseudoxanthoma elasticum-like features and fatal outcome, have been reported. A 56-year-old woman presented with polyneuropathy and a diffuse plane xanthoma-like eruption. Light and electron microscopy studies revealed deposits of amyloid L encasing either normal-looking or short, fragmented elastic fibres in the dermis in a pattern characteristic of amyloid elastosis. The patient had medullary plasmocytosis with lambda light chain restricted expression and underwent autologous stem cell transplantation, which resulted in progressive regression of mucocutaneous signs and stabilization of the polyneuropathy. Our case extends the spectrum of clinical and histopathological presentations of amyloid elastosis. Haematopoietic cell transplantation might improve outcome in patients with multisystem disease.

Amyloidosis↗
PubMed2002

Diagnosis of a gastric mucosa-associated lymphoid tissue lymphoma by endoscopic ultrasonography-guided biopsies in a patient with a parotid gland localization.

We report the case of a 32-year-old man with a low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the parotid gland associated with Sjögren syndrome. He underwent an upper endoscopy as part of the screening of a gastric localization which showed a diffuse non-specific gastritis. However, endoscopic ultrasonography (EUS) evidenced a focal wall thickening of the vertical portion of the smaller curvature. EUS-guided biopsies of this area disclosed a MALT lymphoma, whereas biopsies under endoscopy concluded to mild chronic gastritis. The search for Helicobacter pylori infection remained negative. Four months after treatment with anti-CD20 antibodies, EUS showed a diminution of the abnormal thickening of the second layer. Regression was confirmed histologically on new EUS-guided biopsies. MALT lymphoma is usually considered a localized disease; however, dissemination is probably more frequent than initially believed. Our case reflects the importance of a systematic screening for a gastric localization in patients with MALT lymphoma of the salivary glands. In this situation, association to autoimmune disease such as Sjögren syndrome is more likely to explain the gastric location than infection with H. pylori. Endoscopic ultrasonography has a major impact for the staging of gastric MALT lymphoma, but may also help diagnose focal infiltration by the disease.

Adult↗
PubMed2001

Total body irradiation before allogeneic bone marrow transplantation: is more dose better?

PURPOSE: This study was performed to retrospectively assess the potential influence of total-body irradiation (TBI) dose on overall survival in patients undergoing allogeneic bone-marrow transplants (BMT) for hematologic malignancies. METHODS AND MATERIALS: Between October 1984 and December 1996, 116 patients were conditioned with high-dose chemotherapy and fractionated TBI before allogeneic BMT. The median age was 34 years (range 3-60). The TBI dose was given in 6 fractions, twice-a-day, over 3 days before BMT. The total dose was 10 Gy in 24 patients, 12 Gy in 66 patients, and 13.5 Gy in 26 patients. RESULTS: TBI dose was inversely correlated with overall survival. Five-year survival was 62% for patients conditioned with 10 Gy, 55% for patients conditioned with 12 Gy, and 46% for patients conditioned with 13.5 Gy. Age at BMT was also independently correlated with survival, with the best outcome for patients < 40 years old. CONCLUSION: A TBI dose (fractionated) > 10 Gy may not necessarily be associated with a better outcome in patients undergoing allogeneic bone-marrow transplant for hematologic malignancies.

Adolescent↗
PubMed2001

Accelerated telomere shortening in hematological lineages is limited to the first year following stem cell transplantation.

Using quantitative fluorescence in situ hybridization and flow cytometry, the telomere length of telomere repeat sequences after stem cell transplantation (SCT) were measured. The study included the telomeres of peripheral blood monocytes that should reflect the length of telomeres in stem cells and the telomeres of T lymphocytes that could shorten as a result of peripheral expansion. The loss of telomeres in monocytes and in memory T cells, although accelerated initially, became comparable to the loss of telomeres in healthy controls from the second year after transplantation. In addition, the telomere length in the naive T cells that were produced by the thymus was comparable to the telomere length in the naive T cells of the donor. Compared to the total length of telomeres available, the loss of telomere repeats in leukocytes after SCT resembles the accelerated shortening seen in early childhood and remains, therefore, relatively insignificant.

Adult↗
PubMed2001

Allogeneic bone marrow transplantation is associated with a preferential femoral neck bone loss.

Osteoporosis is a major complication of organ transplantation. Little is known about the risk of developing osteoporosis in bone marrow transplant (BMT) recipients. We studied early and late changes in bone mineral density (BMD), as well as biochemical markers of bone remodeling, in patients at the time of allogeneic BMT (alloBMT) and up to 13 years thereafter. In a cross-sectional study, 102 patients (40 women, 62 men, mean age +/- SEM, 38.9 +/- 1.6 years) were segregated into a first group (A, n = 48) and evaluated before or during the first weeks (mean +/- SD 0.3 +/- 0.1 month, range -0.5 to 3 months) following alloBMT, and a second group (B, n = 54) studied 60.1 +/- 5.6 months (range 6-156 months) following alloBMT. Lumbar spine (LS) BMD was similar in groups A and B and was within normal limits. In contrast, femoral neck (FN) Z- and T-scores were significantly decreased in group B compared with group A (-0.68 +/- 0.14 vs -0.03 +/- 0.14 SD and -0.84 +/- 0.14 vs -0.22 +/- 0.14 SD, respectively; p < or = 0.002). Osteopenia (T-score between -1 and -2.5 SD) was present in 35% of group A and 43% of group B patients (NS). Osteoporosis (T-score < -2.5 SD) was detected in 7% of group B patients, but in none of those in group A (p = 0.05). In a longitudinal study, 56 subjects were evaluated at the time of alloBMT, and 33 and 23 were studied 6 or 12 months later, respectively (13 women, 20 men, 37.5 +/- 1.6 years). All were treated with supplements of calcium and vitamin D. Amenorrheic women received hormone replacement therapy (HRT). Three-monthly pamidronate infusions were given to 15 men and 10 non-amenorrheic women who were osteopenic/osteoporotic or had elevated baseline bone turnover markers. Mean baseline LS and FN Z- and T-scores were within normal range. Six months after BMT, FN BMD decreased by 4.2 +/- 0.7% (p < 0.001), and whole body BMD and bone mineral content by 1.5 +/- 0.4% and 3.1 +/- 0.6%, respectively (p < or = 0.0001). Twelve months after the graft, there was no further significant bone loss and only FN BMD decrease remained significantly different compared with baseline (-5.6 +/- 1.1%, p < or = 0.0001). These results indicate that the risk of decreased BMD is higher for the femoral neck than the lumbar spine and whole body levels in patients with allogeneic bone marrow transplantation, and that bone loss occurs mainly during the first 6 months after the graft.

Adolescent↗
PubMed2001

Human memory T cells: lessons from stem cell transplantation.

Animal models have revealed the rules for the organization of mature T-cell pools. However, in humans, little is known about memory T cells, which differ in lifespan and in the number of times that the same antigen is encountered. Here, Nathalie Rufer and colleagues discuss their findings in stem-cell-transplanted patients, which provide interesting data on the human T-cell compartment.

Animals↗
PubMed2001

Fatal myocardial aspergillosis in an immunosuppressed child.

A girl with resistant acute myeloid leukemia (AML) had a stem cell transplantation. Preceding transplantation, she had recurrent pneumonitis. No causative agent was identified. Despite several antibiotics including high-dose liposomal amphotericin-B, pulmonary infection progressed. Aspergillosis, always considered, could not be documented. She died from cardiac arrest on the second day after transplantation, with no forewarning of previous heart disease. Pericardial and myocardial aspergillosis was an autopsy finding. Pericardial and myocardial aspergillosis, rare manifestations of systemic aspergillosis, should be considered in any immunocompromised patient with long-lasting pulmonary infection, even in the absence of specific cardiac findings.

Amphotericin B↗
PubMed2000

Recovery of immune reactivity after T-cell-depleted bone marrow transplantation depends on thymic activity.

To evaluate the importance of the thymus for the reconstitution of immunity in recipients of a T-cell-depleted bone marrow, we measured the appearance of CD4(+)CD45RA(+)RO(-) naive T cells (thymic rebound), restoration of the diversity of the T-cell-receptor (TCR) repertoire and the response to vaccinations with tetanus toxoid (TT). Repopulation by CD4(+)CD45RA(+)RO(-) thymic emigrants varied among patients, starting at approximately 6 months after transplantation. Young patients reconstituted swiftly, whereas in older patients, the recovery of normal numbers of naive CD4(+) T cells could take several years. Restoration of TCR diversity was correlated with the number of naive CD4(+)CD45RA(+)RO(-) T cells. Moreover, the extent of the thymic rebound correlated with the patient's capacity to respond to vaccinations. Patients without a significant thymic rebound at the moment of vaccination (CD4(+)CD45RA(+)RO(-) T cells less than 30 microL) did not respond, or responded only marginally even after 3 boosts with TT. We conclude that during the first year after transplantation, the absence of an immune response is due mainly to the loss of an adequate T-cell repertoire. Restoration of the repertoire can come only from a thymic rebound that can be monitored by measuring the increase of CD4(+)CD45RA(+)RO(-) naive T cells. This will allow postponing revaccinations to a moment when the patient will be able to respond more effectively. This may be particularly useful in the elderly patient who, owing to low thymic activity, might not yet be able to respond 1 year after transplant when revaccinations are usually scheduled.

Adolescent↗
PubMed1999

CD45 isoform phenotypes of human T cells: CD4(+)CD45RA(-)RO(+) memory T cells re-acquire CD45RA without losing CD45RO.

We have studied the alterations in CD45R phenotypes of CD4(+)CD45RA(-)RO(+) T cells in recipients of T cell-depleted bone marrow grafts. These patients are convenient models because early after transplantation, their T cell compartment is repopulated through expansion of mature T cells and contains only cells with a memory phenotype. In addition, re-expression of CD45RA by former CD4(+)CD45RA(-) T cells can be accurately monitored in the pool of recipient T cells that, in the absence of recipient stem cells, can not be replenished with CD45RA(+) T cells through the thymic pathway. We found that CD4(+)CD45RA(-)RO(+) recipient T cells could re-express CD45RA but never reverted to a genuine CD4(+)CD45RA(+)RO(-) naive phenotype. Even 5 years after transplantation, they still co-expressed CD45RO. In addition, the level of CD45RA and CD45RC expression was lower ( approximately 35 %) than that of naive cells. In contrast, the level of CD45RB expression was comparable to that of naive cells. We conclude that CD4(+)CD45RA(-)RO(+) T cells may re-express CD45(high) isoforms but remain distinguishable from naive cells by their lower expression of CD45RA / RC and co-expression of CD45RO. Therefore, it is likely that the long-lived memory T cell will be found in the population expressing both low and high molecular CD45 isoforms.

Adult↗
PubMed1998

Reconstitution of the T-cell compartment after bone marrow transplantation: restoration of the repertoire by thymic emigrants.

We have studied the reconstitution of the T-cell compartment after bone marrow transplantation (BMT) in five patients who received a graft-versus-host disease (GVHD) prophylaxis consisting of methotrexate, cyclosporin, and 10 daily injections (day -4 to day +5) of Campath-1G. This treatment eliminated virtually all T cells (7 +/- 8 T cells/microL at day 14) which facilitated the analysis of the thymus-dependent and independent pathways of T-cell regeneration. During the first 6 months, the peripheral T-cell pool was repopulated exclusively through expansion of residual T cells with all CD4(+) T cells expressing the CD45RO-memory marker. In two patients, the expansion was extensive and within 2 months, the total number of T cells (CD8>>CD4) exceeded 1,000/microL. In the other three patients, T cells remained low (87 +/- 64 T cells/microL at 6 months) and remained below normal values during the 2 years of the study. In all patients, the first CD4(+)CD45RA+RO- T cells appeared after 6 months and accumulated thereafter. In the youngest patient (age 13), the increase was relatively fast and naive CD4(+) T cells reached normal levels (600 T cells/microL) 1 year later. In the four adult patients (age 25 +/- 5), the levels reached at that time-point were significantly lower (71 +/- 50 T cells/microL). In all patients, the T-cell repertoire that had been very limited, diversified with the advent of the CD4(+)CD45RA+RO- T cells. Cell sorting experiments showed that this could be attributed to the complexity of the T-cell repertoire of the CD4(+)CD45RA+RO- T cells that was comparable to that of a normal individual and that, therefore, it is likely that these cells are thymic emigrants. We conclude that after BMT, the thymus is essential for the restoration of the T-cell repertoire. Because the thymic activity is restored with a lag time of approximately 6 months, this might explain why, in particular in recipients of a T-cell-depleted graft, immune recovery is delayed.

Adolescent↗