Systematic review and meta-analyses of studies of glutamine supplementation in haematopoietic stem cell transplantation.

It is unclear whether supplemental glutamine is of benefit in haematopoietic stem cell transplantation (HSCT). We performed a systematic review and meta-analyses using Cochrane methodology. Seventeen randomized controlled trials (RCTs) were found. There was considerable heterogeneity between studies in terms of patient demographics and glutamine administration schedule. Many of the studies were small and scored poorly on methodological quality. Oral glutamine may reduce mucositis (average mucositis score: standard mean difference -0.38, 95% confidence interval (CI) -0.59 to -0.16) and days of opioids (mean difference -1.95 days, 95% CI -3.66 to -0.25) and GVHD (relative risk 0.42, 95% CI 0.21-0.85). Glutamine (i.v.) may reduce clinical infections (relative risk 0.75, 95% CI 0.58 to 0.97) and positive cultures (relative risk 0.72, 95% CI 0.57-0.91) but may also increase the risk of relapse (relative risk 2.91, 95% CI 1.34-6.29) but this is based on only two small studies. There was no effect of oral or i.v. glutamine on overall transplant-related mortality at day +100. In conclusion, there may be beneficial effects of glutamine in HSCT but larger, well-designed studies are required to confirm the beneficial effects and investigate possible adverse effects.

A case of hepatosplenic gamma-delta T-cell lymphoma with a transient response to fludarabine and alemtuzumab.

Hepatosplenic gamma-delta T-cell lymphoma is a rare, usually fatal lymphoma and available literature on management is sparse. Allografting is probably the only curative option. We describe a further case with a dramatic, though transient response to Fludarabine and Alemtuzumab combination, following a failure of conventional chemotherapy. Given the dreadful prognosis with conventional chemotherapy, it is a regimen worth pursuing as a disease reduction strategy prior to allograft where appropriate.

Transfusion-associated graft-versus-host disease in a patient with Waldenstrom's macroglobulinaemia.

BACKGROUND AND OBJECTIVES: Routine irradiation of cellular blood products is not presently recommended for patients with non-Hodgkin's lymphoma (NHL). MATERIALS AND METHODS: We report the case of a 72-year-old-man with Waldenstrom's macroglobulinaemia who developed transfusion-associated graft-versus-host disease (TA-GvHD) 13 days following a non-irradiated red cell transfusion. RESULTS: The patient had not previously received purine analogues and none of the donors was homozygous for a human leucocyte antigen (HLA) haplotype that was shared by the recipient. Therefore, his only apparent risk factor was lymphoplasmacytoid NHL. CONCLUSIONS: This case further strengthens the argument that NHL per se is a risk factor for TA-GvHD and supports the proposal that the guidelines for prophylactic irradiation of cellular blood products be extended to include all cases of NHL.

Inferior vena cava malformation as a risk factor for deep venous thrombosis in the young.

Conditions which result in hypercoagulable blood or venous stasis may predispose to the development of deep vein thrombosis (DVT). Most of the recently described risk factors for DVT induce a hypercoagulable state. Over a 3-year period we have observed anomaly of the inferior vena cava (IVC) in four young patients presenting with spontaneous unprovoked DVT. This is a greater than expected rate (5% observed versus 0.5% expected). Further, bilateral DVT, which constitutes less than 10% of cases in most series, was present in three of the four cases. Anomaly of the IVC is a rare example of a prevalent congenital condition that predisposes to DVT, presumably by favouring venous stasis. This diagnosis should be considered in young patients with spontaneous and bilateral DVT.

Sight-threatening varicella zoster virus infection after fludarabine treatment.

Varicella zoster virus (VZV) infection involving the posterior segment of the eye after fludarabine treatment has not previously been described. Two patients, who had completed fludarabine treatment 3 and 18 months previously, presented with visual loss that had been preceded by a recent history of cutaneous zoster. The use of the polymerase chain reaction (PCR) for VZV DNA from ocular specimens allowed rapid confirmation of clinical diagnosis and treatment with a good outcome in one patient. With the increasing use of fludarabine and other purine analogues, an awareness of such complications is important because of their potentially sight-threatening consequences.

Translocation (X;5)(q13;q33) in essential thrombocythemia.

We report a novel chromosomal translocation (X;5)(q13;q33) in a woman with no history of prior chemotherapy or radiotherapy, found to have essential thrombocythemia. Aberrations in chromosome 5, mostly deletions of 5q, have been described in essential thrombocythemia; however, a t(X;5) translocation has not been reported.

Acute promyelocytic leukaemia with t(11;17)(q23;q12-21) and a good initial response to prolonged ATRA and combination chemotherapy.

Acute myeloid leukaemia (AML) of FAB subtype M3 is associated with t(15;17)(q22;q21) and a relatively good prognosis when treated with all-trans retinoic acid (ATRA) and combination chemotherapy. Rarely, alternative balanced translocations have been described in this subtype of AML. The translocation t(11;17)(q23;q21) leading to a PLZF/RARalpha rearrangement has been described in a very small number of cases and has been associated with a poor response to ATRA and an adverse prognosis. We describe a case of AML FAB type M3 with this translocation who entered morphological and cytogenetic complete remission after concurrent prolonged ATRA and one course of induction chemotherapy and remains in morphological and molecular remission at 10 months after presentation. This diagnosis therefore may not always be associated with a poor initial response to treatment.

Pathogenetic Aspects of Myelodysplastic Syndromes.

The myelodysplastic syndromes (MDS) are acquired clonal disorders of the bone marrow. They were clearly defined in morphological terms by the French-American-British (FAB) group in 1982, as five conditions each with their own diagnostic criteria, but with the shared characteristics of ineffective blood cell production in one or more cell line, morphological dysplasia and a variable propensity to evolve into acute myeloid leukaemia (AML). In clinical practice patients typically present in old age with macrocytic anaemia, cytopenias, monocytosis and accumulation of marrow blast cells leading in time to fatal bone marrow failure or AML. To date treatment is unable to alter the natural history of MDS except in those few individuals who are able to undergo allogeneic progenitor cell transplantation.

Refractory anaemia with preleukaemic polyclonal haemopoiesis and the emergence of monoclonal erythropoiesis on disease progression.

We describe a young woman with a myelodysplastic syndrome (MDS) of the type refractory anaemia (RA) which remained stable for 11 years and then underwent rapid progression manifested by bone marrow failure with the emergence of a complex clonal cytogenetic abnormality. Peripheral blood granulocytes, mononuclear cells and bone marrow erythroblasts were all polyclonal by X-inactivation analysis detected by the probe M27B during the preleukaemic phase. On disease progression, bone marrow erythroblasts developed an extremely skewed monoclonal pattern of X-inactivation. In some cases of MDS, therefore, polyclonal haemopoiesis can be detected for a considerable time during the preleukaemic phase and we report the demonstration of bone marrow erythroblasts changing from a polyclonal to a monoclonal pattern on disease progression.

Clonal haemopoiesis following cytotoxic therapy for lymphoma.

Patients successfully treated for lymphoma by conventional cytotoxic therapy are at increased risk of developing treatment-related myelodysplasia and acute myeloid leukaemia. In this study we have investigated a group of haematologically normal females in remission from lymphoma for evidence of clonal haemopoiesis as a possible marker for the development of clonal haemopoietic disorders. Unilateral X-inactivation, and hence clonality, can be determined in females heterozygous for X-linked restriction fragment length polymorphisms by differences in methylation between active and inactive X-chromosomes. We have studied methylation patterns at the DXS255 locus and the phosphoglycerate kinase (PGK) gene in 25 females in remission from lymphoma and compared them to 35 normal females. Unilateral X-inactivation was detected in 4/15 patients in remission from lymphoma versus 2/27 normals at the DXS255 locus and in 4/13 treated lymphoma patients versus 0/11 normals at the PGK locus. Six individuals were analysed by both techniques with complete concordance. Unilateral X-inactivation was more common following cytotoxic therapy for lymphoma (7/25) than in normals (2/35) (p < 0.025) and in the lymphoma cohort was associated with increasing time from the end of therapy (p = 0.03). Patients in remission from lymphoma have an increased incidence of clonal haemopoiesis compared to normal individuals. This may be due to either the clonal expansion of an abnormal genetically damaged stem cell or a variation of normal haemopoiesis. Prospective studies will establish whether this finding is associated with an increased risk of developing treatment-related myelodysplasia and acute myeloid leukaemia.

Methylation of the DXS255 hypervariable locus 5' CCGG site may be affected by factors other than X-chromosome activation status.

Differences in the methylation status of certain cytosine residues between active and inactive X chromosomes can be used to determine X-inactivation in females heterozygous for X-linked restriction fragment length polymorphisms. We have studied methylation patterns in 105 females heterozygous at the DXS255 locus by Southern blotting of PstI and MspI or HpaII double digests and hybridization with the probe M27B. Unequivocal patterns of unilateral or bilateral X-inactivation were obtained in 15/64 and 49/64 cases, respectively. In the remaining 41 cases the results were unclear due to the absence of HpaII digestion of one or both PstI fragments. In 7 samples an unequivocal digestion pattern was demonstrated on repeat analysis, suggesting that the initial ambiguous pattern was due to incomplete HpaII digestion. In certain individuals, methylation at the 5' CCGG DXS255 locus may be affected by factors other than X-inactivation, making analysis of clonality with the M27B probe impossible. These individuals should be clearly identified in studies of clonality.

Cell-cycle progression rates and sister chromatid exchange frequencies in the bone marrow of patients with myelodysplastic syndrome and acute myeloid leukemia.

The proliferation characteristics of leukemic cells may be a determining factor in disease course and response to therapy. The present study compares the rate of cell-cycle progression in the bone marrow of 16 hematologically normal subjects, 19 patients with acute myeloid leukemia (AML), and 23 patients with myelodysplastic syndrome (MDS). The frequency of sister chromatid exchanges (SCE) in bone marrow cells is also compared. MDS and AML patients showed a reduction in the rate of cell-cycle progression compared with normal subjects. Patients with 'high risk' MDS (RAEB/RAEB-t) did not differ significantly from patients with AML but had a significantly slower rate of cell-cycle progression than patients with 'low-risk' MDS (PASA/RA). There was no correlation between the rate of cell-cycle progression and clonal karyotype status or the percentage of blast cells in either MDS or AML. There were no significant differences in SCE frequency between normal subjects and MDS or AML patients.

Extended cytogenetic follow-up of patients with myelodysplastic syndrome (MDS).

The prognostic significance of clonal karyotype status in myelodysplastic syndrome (MDS) is assessed after an extended follow-up period of 5 years. There are three karyotype, single abnormalities or multiple abnormalities at the time of referral. However, there is no correlation between the size of the abnormal clone and prognosis. Karyotype status has independent prognostic significance in 'high risk' MDS so that patients with a refractory anaemia with excess of blasts (RAEB)/RAEB in transformation (RAEB-t) and a normal karyotype survive significantly longer than those with an abnormal karyotype (P < 0.001) and do not differ significantly from patients with refractory anaemia (RA). Significant differences in survival according to karyotype status are also seen in patients with chronic myelomonocytic leukaemia (P < 0.001) but not in those with primary acquired sideroblastic anaemia and RA. Among patients studied sequentially, those who retained a normal karyotype survived significantly longer than those who developed an abnormality on follow-up (P < 0.001). The risk of leukaemic transformation was also increased in patients who presented with or subsequently developed a clonal karyotype abnormality compared with those who remained normal (P < 0.05).

Clonal lymphocytes are detectable in only some cases of MDS.

Clonal analysis of lymphocytes from patients with myelodysplastic syndrome (MDS) has been carried out using X-chromosome inactivation patterns detected by the probe M27 beta, and by polymerase chain reaction amplification of the immunoglobulin heavy chain gene hypervariable region, CDR3. Of 32 female patients heterozygous for M27 beta only seven (22%) demonstrate monoclonality of peripheral blood lymphocytes. 12 (37%) give unequivocal polyclonal results and the remaining cases give patterns of X-inactivation which cannot be interpreted either way. A study of 68 MDS patients showed five (7%) with a population of B-cells with a monoclonal rearrangement of CDR3 compared with none out of 60 normal individuals, none out of 15 with B-non Hodgkin lymphoma (B-NHL) in remission and 19 out of 25 (75%) of cases of B-chronic lymphocytic leukaemia (B-CLL). Monoclonal lymphocytes were found by both techniques in only two females with MDS. We conclude that the presence of polyclonal lymphocytes is a common finding in patients with MDS.