'Nipped in the Budd': hepatic venous outflow obstruction in evolution

Hepatic venous thrombosis (Budd-Chiari) in evolution is a rare phenomenon and carries a high morbidity and mortality. We describe the case of a 39-year-old Bangladeshi lady who presented with severe abdominal pain secondary to a perforated duodenal ulcer and during her hospital admission developed an asymptomatic Budd-Chiari syndrome (BCS). Our report highlights the important role of an inflammatory focus, and how this process with an associated reactive thrombocytosis may act as a trigger for the development of BCS in an individual with predisposing risk factors. Our patient had been on the contraceptive pill, and was homozygous for the C677T mutation of 5,10-methylenetetrahydrofolate reductase, which results in hyperhomocysteinaemia. These pro-thrombotic risk factors were compounded by the thrombogenic potential of subsequent laparoscopic surgery, and resulted in an evolving thrombus that progressed into the inferior vena cava causing hepatic infarction. A particular feature of this case was the radiological demonstration of complete regression of the thrombus and the hepatic parenchymal changes, upon resolution of the inflammation and normalization of the platelet count. These changes occurred with oral anticoagulation as the only treatment modality, since our patient declined systemic thrombolysis. The demonstration of complete radiological resolution raises the question of how long one should continue oral anticoagulants and, indeed, whether in some instances a conservative approach may be the best management strategy for evolving BCS.     

Alloreactive T cell clonotype recruitment in a mixed lymphocyte reaction: implications for graft engineering

OBJECTIVE: The selective elimination of alloreactive T cells from donor stem cell grafts prior to hematopoietic stem cell transplantation (HSCT) is an important goal in the prevention of graft-vs-host disease (GVHD). However, in HLA-identical donor-recipient pairs, it has proven difficult to identify alloreactive T cells using in vitro systems pretransplant due, in part, to their low frequency and a lack of methodological standardization. To better understand the alloresponse between HLA-identical related pairs, we characterized the alloreactive T cells generated in a mixed lymphocyte reaction (MLR) assay system. METHODS: HSCT donor peripheral blood mononuclear cells (responder) were labeled with carboxyfluorescein diacetate, succinimidyl ester (CFSE) dye and cocultured with irradiated HSCT recipient cells (stimulator) in a one-way MLR. Alloreactive T cells were sorted by upregulation of activation markers (CD25 in most cases) and the responding clonotypes were defined by sequencing the complementarity region 3 (CDR3) of the T cell receptor beta-chain. RESULTS: We show that the recruitment of alloreactive CD4(+) T cells is highly variable. Oligoclonal CD4(+) T-cell expansions in repeated MLRs performed in the same donor-recipient pair showed inconsistent recruitment of clonotypes. The recruitment of alloreactive CD8(+) T cells was more consistent in repeated assays, with the same clonotypes identified in the same donor-recipient pair performed under different conditions. CONCLUSION: Taken together, our data show that even in culture conditions constrained to eliminate background proliferation, stochastic events and low precursor frequencies preclude reproducible elicitation of immunodominant T cell clonotypes with the potential to cause GVHD.     

Pregnancy after bariatric surgery: Consensus recommendations for periconception,antenatal and postnatal care

The objective of the study is to provide evidence‐based guidance on nutritional management and optimal care for pregnancy after bariatric surgery. A consensus meeting of international and multidisciplinary experts was held to identify relevant research questions in relation to pregnancy after bariatric surgery. A systematic search of available literature was performed, and the ADAPTE protocol for guideline development followed. All available evidence was graded and further discussed during group meetings to formulate recommendations. Where evidence of sufficient quality was lacking, the group made consensus recommendations based on expert clinical experience. The main outcome measures are timing of pregnancy, contraceptive choice, nutritional advice and supplementation, clinical follow‐up of pregnancy, and breastfeeding. We provide recommendations for periconception, antenatal, and postnatal care for women following surgery. These recommendations are summarized in a table and print‐friendly format. Women of reproductive age with a history of bariatric surgery should receive specialized care regarding their reproductive health. Many recommendations are not supported by high‐quality evidence and warrant further research. These areas are highlighted in the paper.     

Early reconstitution of the T-cell repertoire after non-myeloablative peripheral blood stem cell transplantation is from post-thymic T-cell expansion and is unaffected by graft-versus-host disease or mixed chimaerism

To study immune recovery after non-myeloablative, reduced-intensity stem cell allografts (NST) and T-cell-depleted myeloablative transplants (TCD), we measured T-cell subset recovery by flow cytometry, T-cell repertoire by spectratyping and thymic T-cell output using a T-cell receptor excision circle (TREC) assay. We found a rapid and comparable increase in lymphocyte numbers in both NST and TCD, supporting the presence of a powerful drive for lymphocyte recovery after transplant. Spectratyping on d 45 and 100 revealed almost complete normalization of the T-cell repertoire in NST patients by d 45, whereas TCD patients demonstrated marked skewing of the repertoire, persisting to d 100. After NST, there was a significantly higher number of TREC-positive CD4+ and CD8+ cells (P = 0.02 and P = 0.01 respectively). However, in both NST and TCD, early T-cell recovery after transplant appeared to result entirely from post-thymic T cells, the expansion pattern of which is most influenced by the starting T-cell dose, but not markedly by graft-versus-host disease (GVHD) or mixed chimaerism. These results define important qualitative differences in the T-cell repertoire according to the type of transplant schedule used.     

Diabetes in the parents of children with Type I diabetes

Aims/hypothesis. Previous studies have reported an excess of Type II (non-insulin-dependent) diabetes mellitus in parents of children with Type I (insulin-dependent) diabetes mellitus. We set out to characterise the clinical and immunogenetic features of diabetes in parents of affected children, and to test the hypothesis that there is no excess of Type II diabetes within this population. Methods. Clinical details were collected from 3164 parents of 1641 children with Type I diabetes participating in the Bart's-Oxford study of childhood diabetes. Islet cell antibodies, antibodies to GAD and IA-2, and HLA class II genotype were determined in a subset of this group. Individuals were assigned a classification of Type I diabetes on the basis of clinical features and measurement of islet autoantibodies. Results. Of 184 parents with diabetes, 138 (75 %) were on insulin. At least one islet autoantibody was detected in 90 (59 %) of 152 parents tested, and of 116 who were HLA-typed, 23 (20 %) had the highest risk genotype HLA-DRB1^*03-DQA1*0501-DQB1^*0201 / DRB1*04-DQA1^*0301-DQB1*0302. Of 46 non-insulin-treated parents, 12 had islet autoantibodies. Of all parents, 141 (4.5 %) were therefore classified as having Type I diabetes, and 31 (0.98 %) as Type II diabetes; 12 could not be classified because of missing data or samples. Conclusion/interpretation. Autoimmune diabetes can present late and without immediate need for insulin treatment in parents of children with the disease. Previous studies have categorised this as Type II diabetes. Our study suggests that there is no excess of non-autoimmune diabetes in the families of children with Type I diabetes. [Diabetologia (2002) 45: ▪–▪] Received: 7 November 2001 and in revised form: 3 January 2002     

High avidity myeloid leukemia-associated antigen-specific CD8+ T cells preferentially reside in the bone marrow

The activity of allogeneic CD8(+) T cells specific for leukemia-associated antigens (LAAs) is thought to mediate, at least in part, the curative effects of hematopoietic stem cell transplantation (HSCT) in myeloid malignancies. However, the identity and nature of clinically relevant LAA-specific CD8(+) T-cell populations have proven difficult to define. Here, we used a combination of coreceptor-mutated peptide-major histocompatibility complex class I (pMHCI) tetramers and polychromatic flow cytometry to examine the avidity profiles, phenotypic characteristics, and anatomical distribution of HLA A*0201-restricted CD8(+) T-cell populations specific for LAAs that are over-expressed in myeloid leukemias. Remarkably, LAA-specific CD8(+) T-cell populations, regardless of fine specificity, were confined almost exclusively to the bone marrow; in contrast, CD8(+) T-cell populations specific for the HLA A*0201-restricted cytomegalovirus (CMV) pp65(495-503) epitope were phenotypically distinct and evenly distributed between bone marrow and peripheral blood. Furthermore, bone marrow-resident LAA-specific CD8(+) T cells frequently engaged cognate antigen with high avidity; notably, this was the case in all tested bone marrow samples derived from patients who achieved clinical remission after HSCT. These data suggest that concomitant examination of bone marrow specimens in patients with myeloid leukemias might yield more definitive information in the search for immunologic prognosticators of clinical outcome.     

The HIV-1 reservoir in eight patients on long-term suppressive antiretroviral therapy is stable with few genetic changes over time

The source and dynamics of persistent HIV-1 during long-term combinational antiretroviral therapy (cART) are critical to understanding the barriers to curing HIV-1 infection. To address this issue, we isolated and genetically characterized HIV-1 DNA from naïve and memory T cells from peripheral blood and gut-associated lymphoid tissue (GALT) from eight patients after 4–12 y of suppressive cART. Our detailed analysis of these eight patients indicates that persistent HIV-1 in peripheral blood and GALT is found primarily in memory CD4⁺ T cells [CD45RO⁺/CD27(^+/−)]. The HIV-1 infection frequency of CD4⁺ T cells from peripheral blood and GALT was higher in patients who initiated treatment during chronic compared with acute/early infection, indicating that early initiation of therapy results in lower HIV-1 reservoir size in blood and gut. Phylogenetic analysis revealed an HIV-1 genetic change between RNA sequences isolated before initiation of cART and intracellular HIV-1 sequences from the T-cell subsets after 4–12 y of suppressive cART in four of the eight patients. However, evolutionary rate analyses estimated no greater than three nucleotide substitutions per gene region analyzed during all of the 4–12 y of suppressive therapy. We also identified a clearly replication-incompetent viral sequence in multiple memory T cells in one patient, strongly supporting asynchronous cell replication of a cell containing integrated HIV-1 DNA as the source. This study indicates that persistence of a remarkably stable population of infected memory cells will be the primary barrier to a cure, and, with little evidence of viral replication, this population could be maintained by homeostatic cell proliferation or other processes.Combinational, antiretroviral therapy (cART) effectively suppresses but does not eradicate HIV-1 infection (1). Persistent low-level HIV-1 can still be detected in plasma (2–7) and cellular reservoirs (8–10) even after several years of suppressive cART, and cessation of current treatments invariably results in resumption of viral replication. Resting-memory CD4⁺ T cells are a well-defined reservoir of HIV-1, and the reservoir is established when an activated CD4⁺ T cell becomes infected by HIV-1 but transitions to a resting state (9) or perhaps when resting cells are infected directly (11–13). Central and transitional memory T cells have recently been identified as major contributors to the HIV-1 reservoir in the memory T-cell population (14). Naïve T cells have also been demonstrated to contain HIV-1 DNA in patients on suppressive therapy, although at a lower infection frequency than the memory T-cell population (15). In addition, many other cell types, including monocyte/macrophages, have been proposed to play a role in HIV-1 persistence (reviewed in ref. 16). These long-lived HIV-1–infected cells have been detected in peripheral blood. Several studies, however, suggest that the reservoir is largely established and maintained in lymphoid tissues, and that the infected cells circulating in blood may not be representative of the population of infected cells in tissue. For example, the majority of lymphocytes are sequestered in the gastrointestinal tract, and gut-associated lymphoid tissue (GALT) has been shown to be a major viral reservoir in patients on suppressive antiretroviral therapy (17–22).In addition to the persistence of long-lived, latently infected cells, low-level viral replication has been proposed as a mechanism that maintains HIV-1 during cART. If complete viral replication cycles persist, despite suppressive antiretroviral therapy, this would lead to de novo cellular infection and a constant replenishment of the viral reservoir. Investigations into whether HIV-1 replication continues during suppressive therapy have been carried out with peripheral blood and GALT samples but have led to potentially contradictory results. Some studies have found an absence of genetic evolution in viral reservoirs (23–29) and no reduction of plasma RNA during intensification of cART (30, 31), suggesting that cART is effective in preventing viral replication in these anatomical sites. In contrast, increased numbers of 2-long terminal repeat circles in peripheral blood mononuclear cells and decreased amounts of unspliced HIV-1 RNA in CD4⁺ T cells isolated from the terminal ileum have been reported during raltegravir intensification, supporting the concept that some viral replication can occur despite suppressive cART (32, 33). Thus, the role of on-going replenishment via cycles of replication as a cause of persistence is not fully understood.To investigate the source and dynamics of HIV-1 reservoirs in peripheral blood and GALT, we sorted and genetically characterized intracellular HIV-1 from subsets of memory T cells, naïve T cells, and myeloid cells from these two compartments from eight patients who had been on suppressive therapy with undetectable viral loads (<40–75 copies/mL) for 4–12 y: five who initiated therapy during acute/early infection and three who initiated therapy during chronic infection. Our aim was to investigate the nature of the infected cell population during cART and explore the role of HIV-1 replication, as reflected by nucleotide sequence substitutions in maintaining this reservoir. Our study revealed that both memory T cells and naïve T cells harbor HIV-1 DNA after long-term suppressive therapy, and the infection frequency of these T cells was higher in patients treated during chronic infection compared with patients treated during early infection. In-depth phylogenetic analysis revealed little or no change in viral structure or divergence over time within the viral sequences isolated from the different T-cell populations compared with sequences isolated from plasma collected just before initiation of cART, indicating lack of on-going replication during long-term suppressive therapy.     

Near fatal ingestion of oil of cloves

A case of ingestion of oil of cloves is presented, which resulted in coma, fits, a coagulopathy, and acute liver damage. This is not unlike the syndrome produced in the late stages of a substantial paracetamol overdose, and a similar treatment regimen is proposed.