Photodynamic therapy for inflammatory choroidal neovascularisation unresponsive to immunosuppression

Aim: To report on visual and angiographic outcomes of a consecutive series of patients with inflammatory choroidal neovascular membranes (CNV) unresponsive to systemic immunosuppression treated with photodynamic therapy (PDT). Methods: The medical records of six consecutive patients with inflammatory CNVs that failed to respond to systemic immunosuppression and that later underwent PDT were retrospectively reviewed. Patient demographics, visual acuity, and fluorescein angiographic findings were evaluated. Results: There were five females and one male with a mean age of 40.8 years (range 35-58 years). Four patients had clinical features consistent with punctate inner choroidopathy and two with presumed ocular histoplasmosis. In all cases clinical signs of CNV activity, including subretinal fluid, subretinal blood, hard exudates, and/or recent decrease in visual acuity were present prior to PDT. All patients had been treated with high dose systemic immunosuppressants, which failed to induce regression of the CNV and/or to improve vision. The CNVs were subfoveal in five patients and juxtafoveal in one; all were classified as predominantly classic. Following PDT an improvement in vision occurred in all cases (median improvement of 18 letters, range 3-42 letters). At last follow up, signs of decreased activity in the CNV were detected in all cases. Patients were followed for a median of 10 months (range 9-20 months). Conclusion: PDT appears to be a useful option in the management of patients with inflammatory CNVs unresponsive to immunosuppressive therapies.

Treatment of intestinal Behçet's syndrome with chimeric tumour necrosis factor alpha antibody

Few patients with Behçet's syndrome have gastrointestinal ulceration. Such patients are difficult to treat and have a higher mortality. Faced with refractory symptoms in two patients with intestinal Behçet's, we used the tumour necrosis factor alpha (TNF-alpha) monoclonal antibody infliximab to induce remission. Both women (one aged 27 years, the other 30 years) presented with orogenital ulceration, pustular rash, abdominal pain, bloody diarrhoea due to colonic ulceration, weight loss, and synovitis. One had thrombophlebitis, digital vasculitis, perianal fistula, and paracolic abscess; the other had conjunctivitis and an ulcer in the natal cleft. Treatment with prednisolone, methyl prednisolone, and thalidomide in one and prednisolone, colchicine, and cyclosporin in the other was ineffective. After full discussion, infliximab (3 mg/kg, dose reduced because of recent sepsis in one, and 5 mg/kg in the other) was administered. Within 10 days the ulcers healed, with resolution of bloody diarrhoea and all extraintestinal manifestations. A second infusion of infliximab was necessary eight weeks later in one case, followed by sustained (>15 months) remission on low dose thalidomide. Remission was initially sustained for 12 months in the other but thalidomide had to be stopped due to intolerance, and a good response to retreatment lasted only 12 weeks without immunosuppression, before a third infusion. The cause of Behçet's syndrome is unknown but peripheral blood CD45 gammadelta T cells in Behçet's produce >50-fold more TNF-alpha than controls when stimulated with phorbol myristate acetate and anti-CD3. Infliximab could have a role for inducing remission in Behçet's syndrome.

Dietary exposure to aflatoxin from maize and groundnut in young children from Benin and Togo, West Africa

Aflatoxins are a family of fungal toxins that are carcinogenic to man and cause immunosuppression, cancer and growth reduction in animals. We conducted a cross-sectional study among 480 children (age 9 months to 5 years) across 4 agroecological zones (SS, NGS, SGS and CS) in Benin and Togo to identify the effect of aflatoxin exposure on child growth and assess the pattern of exposure. Prior reports on this study [Gong, Y.Y., Cardwell, K., Hounsa, A., Egal, S., Turner, Hall, A.J., Wild, C.P., 2002. Dietary aflatoxin exposure and impaired growth in young children from Benin and Togo: cross sectional study. British Medical Journal 325, 20-21, Gong, Y.Y., Egal, S., Hounsa, A., Turner, P.C., Hall, A.J., Cardwell, K., Wild, C.P., 2003. Determinants of aflatoxin exposure in young children from Benin and Togo, West Africa: the critical role of weaning and weaning foods. International Journal of Epidemiology, 32, 556-562] showed that aflatoxin exposure among these children is widespread (99%) and that growth faltering is associated with high blood aflatoxinalbumin adducts (AF-alb adducts), a measure of recent past exposure. The present report demonstrates that consumption of maize is an important source of aflatoxin exposure for the survey population. Higher AF-alb adducts were correlated with higher A. flavus (CFU) infestation of maize (p=0.006), higher aflatoxin contamination (ppb) of maize (p<0.0001) and higher consumption frequencies of maize (p=0.053). The likelihood of aflatoxin exposure from maize was particularly high in agro-ecological zones where the frequency of maize consumption (SGS and CS), the presence of allatoxin in maize (SGS) or the presence of A. flavus on maize (NGS and SGS) was relatively high. Socio-economic background did not affect the presence of A. flavus and aflatoxin in maize, but better maternal education was associated with lower frequencies of maize consumption among children from the northernmost agro-ecological zone (SS) (p=0.001). The impact of groundinit consumption on aflatoxin exposure was limited in this population. High AF-alb adduct levels were correlated with high prevalence of A. flavus and aflatoxin in groundinit, but significance was weak after adjustment for weaning status, agro-ecological zone and maternal socio-economic status (resp. p = 0.091 and p = 0.083). Ingestion of A. flavus and aflatoxin was high in certain agro-ecological zones (SS and SGS) and among the higher socio-economic strata due to higher frequencies of groundnut consumption. Contamination of groundnuts was similar across socio-economic and agroecological boundaries.

In conclusion, dietary exposure to aflatoxin from groundnut was less than from maize in young children from Benin and Togo. Intervention strategies that aim to reduce dietary exposure in this population need to focus on maize consumption in particular, but they should not ignore consumption of groundnuts. (c) 2005 Elsevier B.V. All rights reserved.

Limbal stem cells of the corneal epithelium

Stem cells have certain unique characteristics, which include longevity, high capacity of self-renewal with a long cell cycle time and a short S-phase duration, increased potential for error-free proliferation, and poor differentiation. The ocular surface is made up of two distinct types of epithelial cells, constituting the conjunctival and the corneal epithelia. Although anatomically continuous with each other at the corneoscleral limbus, the two cell phenotypes represent quite distinct subpopulations. Stem cells for the cornea reside at the corneoscleral limbus. The limbal palisades of Vogt and the interpalisade rete ridges are believed to be repositories of stem cells. The microenvironment of the limbus is considered to be important in maintaining the stemness of stem cells. Limbal stem cells also act as a 'barrier' to conjunctival epithelial cells and normally prevent them from migrating on to the corneal surface. Under certain conditions, however, the limbal stem cells may be partially or totally depleted, resulting in varying degrees of stem cell deficiency with resulting abnormalities in the corneal surface. Such deficiency of limbal stem cells leads to 'conjunctivalization' of the cornea with vascularization, appearance of goblet cells, and an irregular and unstable epithelium. This results in ocular discomfort and reduced vision. Partial stem cell deficiency can be managed by removing the abnormal epithelium and allowing the denuded cornea, especially the visual axis, to resurface with cells derived from the remaining intact limbal epithelium. In total stem cell deficiency, autologous limbus from the opposite normal eye or homologous limbus from living related or cadaveric donors can be transplanted on to the affected eye. With the latter option, systemic immunosuppression is required. Amniotic membrane transplantation is a useful adjunct to the above procedures in some instances. Copyright (C) 2000 Elsevier Science Inc.

Allo-limbal transplantation in patients with limbal stem cell deficiency

Aim - To report the outcome of a series of patients with stem cell deficiency who underwent allo-limbal transplantation and to describe a technique for this procedure. Methods - Six consecutive patients underwent allo-limbal stem cell transplantation. The primary diagnosis included alkali burn (n = 2), trachoma (n = 1), chronic rosacea blepharitis and keratoconjunctivitis (n = 1), aniridia (n = 1), and Stevens-Johnson syndrome (n = 1). The limbal rim consisted of peripheral cornea and perilimbal sclera, FK-506 was used postoperatively for immunosuppression. Results - The length of follow up ranged from 3 to 24 months (mean follow up 11.8 (SD 9.3) months). The outcome was considered satisfactory in five of six cases. The corneal surface was completely epithelialised within 2 weeks, and there was a substantial improvement in vision and symptoms. One patient had recurrent epithelial defects related to eyelid abnormalities. No side effects associated with systemic immunosuppression were noted. Conclusion - Allo-limbal transplantation, with systemic immunosuppression with FK-506 is useful in reconstruction of the ocular surface with improvement in vision in patients with severe stem cell deficiency.

A systematic literature review of surgical interventions for limbal stem cell deficiency in humans

PURPOSE: To evaluate the relative benefits and to identify any adverse effects of surgical interventions for limbal stem cell deficiency (LSCD).

DESIGN: Systematic literature review.

METHODS: We searched the following electronic databases from January 1, 1989 through September 30, 2006: MEDLINE, EMBASE, Science citation index, BIOSIS, and the Cochrane Library. In addition, reference lists were scanned to identify any additional reports. The quality of published reports was assessed using standard methods. The main outcome measure was improvement in vision of at least two Snellen lines of best-corrected visual acuity (BCVA). Data on adverse outcomes also were collected.

RESULTS: Twenty-six studies met the inclusion criteria. There were no randomized controlled studies. All 26 studies were either prospective or retrospective case series. For bilateral severe LSCD, keratolimbal allograft was the most common intervention with systemic immunosuppression. Other interventions included eccentric penetrating keratolimbal allografts and cultivated autologous oral mucosal epithelial grafts. An improvement in BCVA of two lines or more was reported in 31% to 67% of eyes. For unilateral severe LSCD, the most common surgical intervention was contralateral conjunctival limbal autograft, with 35% to 88% of eyes gaining an improvement in BCVA of two lines or more. The only study evaluating partial LSCD showed an improvement in BCVA of two lines or more in 39% of eyes.

CONCLUSIONS: Studies to date have not provided strong evidence to guide clinical practice on which surgery is most beneficial to treat various types of LSCD. Standardized data collection in a multicenter LSCD register is suggested.

Caveolin-1 single nucleotide polymorphism in antineutrophil cytoplasmic antibody associated vasculitis

Immunosuppression is cornerstone treatment of antineutrophil cytoplasmic antibody associated vasculitis (AAV) but is later complicated by infection, cancer, cardiovascular and chronic kidney disease. Caveolin-1 is an essential structural protein for small cell membrane invaginations known as caveolae. Its functional role has been associated with these complications. For the first time, caveolin-1 (CAV1) gene variation is studied in AAV.

Proteomics on porcine haptoglobin and IgG/IgA show protein species distribution and glycosylation pattern to remain similar in PCV2-SD infection

Haptoglobin (Hp) and immunoglobulins are plasma glycoproteins involved in the immune reaction of the organism after infection and/or inflammation. Porcine circovirus type 2-systemic disease (PCV2-SD), formerly known as postweaning multisystemic wasting syndrome (PMWS), is a globally spread pig disease of great economic impact. PCV2-SD affects the immunological system of pigs causing immunosuppression. The aim of this work was to characterize the Hp protein species of healthy and PCV2-SD affected pigs, as well as the protein backbone and the glycan chain composition of porcine Hp. PCV2-SD affected pigs had an increased overall Hp level, but it did not affect the ratio between Hp species. Glycoproteomic analysis of the Hp β subunits confirmed that porcine Hp is N-glycosylated and, unexpectedly, O-glycosylated, a PTM that is not found on Hp from healthy humans. The glyco-profile of porcine IgG and IgA heavy chains was also characterized; decreased levels of both proteins were found in the investigated group of PCV2-SD affected pigs. Obtained results indicate that no significant changes in the N- and O-glycosylation patterns of these major porcine plasma glycoproteins were detectable between healthy and PCV2-SD affected animals.

Trade-offs between personal immunity and reproduction in the burying beetle, Nicrophorus vespilloides

How are resources split between caring for offspring and self-maintenance? Is the timing of immune challenge important? In burying beetles challenging the immune system prior to breeding does not affect the total number and quality of offspring produced during the individual's lifetime. However, the immune system is suppressed during breeding and if an immune challenge is presented during this time the beetle will upregulate its immune system, but at the detriment to the number of offspring produced during that breeding opportunity.We know that parental investment and immune investment are costly processes, but it is unclear which trait will be prioritized when both may be required. Here, we address this question using the burying beetle Nicrophorus vespilloides, carrion breeders that exhibit biparental care of young. Our results show that immunosuppression occurs during provision of parental care. We measured phenoloxidase (PO) on Days 1-8 of the breeding bout and results show a clear decrease in PO immediately from presentation of the breeding resource onward. Having established baseline immune investment during breeding we then manipulated immune investment at different times by applying a wounding challenge. Beetles were wounded prior to and during the parental care period and reproductive investment quantified. Different effects on reproductive output occur depending on the timing of wounding. Challenging the immune system with wounding prior to breeding does not affect reproductive output and subsequent lifetime reproductive success (LRS). LRS is also unaffected by applying an immune elicitor prior to breeding, though different arms of the immune system are up/downregulated, perhaps indicating a trade-off between cellular and humoral immunity. In contrast, wounding during breeding reduces reproductive output and to the greatest extent if the challenge is applied early in the breeding bout. Despite being immunosuppressed, breeding beetles can still respond to wounding by increasing PO, albeit not to prebreeding levels. This upregulation of PO during breeding may affect parental investment, resulting in a reduction in reproductive output. The potential role of juvenile hormone in controlling this trade-off is discussed.

Risk of myeloid neoplasms after solid organ transplantation

Solid organ transplant recipients have elevated cancer risks, owing in part to pharmacologic immunosuppression. However, little is known about risks for hematologic malignancies of myeloid origin. We linked the US Scientific Registry of Transplant Recipients with 15 population-based cancer registries to ascertain cancer occurrence among 207 859 solid organ transplants (1987–2009). Solid organ transplant recipients had a significantly elevated risk for myeloid neoplasms, with standardized incidence ratios (SIRs) of 4.6 (95% confidence interval 3.8–5.6; N=101) for myelodysplastic syndromes (MDS), 2.7 (2.2–3.2; N=125) for acute myeloid leukemia (AML), 2.3 (1.6–3.2; N=36) for chronic myeloid leukemia and 7.2 (5.4–9.3; N=57) for polycythemia vera. SIRs were highest among younger individuals and varied by time since transplantation and organ type (Poisson regression P<0.05 for all comparisons). Azathioprine for initial maintenance immunosuppression increased risk for MDS (P=0.0002) and AML (2–5 years after transplantation, P=0.0163). Overall survival following AML/MDS among transplant recipients was inferior to that of similar patients reported to US cancer registries (log-rank P<0.0001). Our novel finding of increased risks for specific myeloid neoplasms after solid organ transplantation supports a role for immune dysfunction in myeloid neoplasm etiology. The increased risks and inferior survival should heighten clinician awareness of myeloid neoplasms during follow-up of transplant recipients.

Factors influencing survival after kidney transplant failure

BACKGROUND: The failure of a kidney transplant is now a common reason for initiation of dialysis therapy. Kidney transplant recipients commencing dialysis have greater morbidity and mortality than transplant-naïve, incident dialysis patients. This study aimed to identify variables associated with survival after graft failure.

METHODS: All recipients of first, deceased donor kidney transplants performed in Northern Ireland between 1986 and 2005 who had a functioning graft at 12 months were included (n = 585). Clinical and blood-derived variables (age, gender, primary renal disease, diabetic status, smoking status, human leukocyte antigen (HLA) mismatch, acute rejection episodes, immunosuppression, cardiovascular disease, graft survival, haemoglobin, albumin, phosphate, C reactive protein, estimated glomerular filtration rate (eGFR), rate of eGFR decline, dialysis modality, and access) were collected prospectively and investigated for association with re-transplantation and survival. The association between re-transplantation and survival was explored by modelling re-transplantation as a time-dependent covariate.

RESULTS: Median follow-up time was 12.1 years. Recipients with a failing graft (158/585) demonstrated rapid loss of eGFR prior to graft failure, reducing the time available to plan for alternative renal replacement therapy. Median survival after graft failure was 3.0 years. In multivariate analysis, age and re-transplantation were associated with survival after graft failure. Re-transplantation was associated with an 88% reduction in mortality.

CONCLUSIONS: Optimal management of kidney transplant recipients with failing grafts requires early recognition of declining function and proactive preparation for re-transplantation given the substantial survival benefit this confers. The survival benefit associated with re-transplantation persists after prolonged exposure to immunosuppressive therapy.

Analysis of single nucleotide polymorphisms implicate mTOR signalling in the development of new-onset diabetes after transplantation

Introduction
Despite excellent first year outcomes in kidney transplantation, there remain significant long-term complications related to new-onset diabetes after transplantation (NODAT). The purpose of this study was to validate the findings of previous investigations of candidate gene variants in patients undergoing a protocolised, contemporary immunosuppression regimen, using detailed serial biochemical testing to identify NODAT development.

Methods
One hundred twelve live and deceased donor renal transplant recipients were prospectively followed-up for NODAT onset, biochemical testing at days 7, 90, and 365 after transplantation. Sixty-eight patients were included after exclusion for non-white ethnicity and pre-transplant diabetes. Literature review to identify candidate gene variants was undertaken as described previously.

Results
Over 25% of patients developed NODAT. In an adjusted model for age, sex, BMI, and BMI change over 12 months, five out of the studied 37 single nucleotide polymorphisms (SNPs) were significantly associated with NODAT: rs16936667:PRDM14 OR 10.57;95% CI 1.8–63.0;p = 0.01, rs1801282:PPARG OR 8.5; 95% CI 1.4–52.7; p = 0.02, rs8192678:PPARGC1A OR 0.26; 95% CI 0.08–0.91; p = 0.03, rs2144908:HNF4A OR 7.0; 95% CI 1.1–45.0;p = 0.04 and rs2340721:ATF6 OR 0.21; 95%CI 0.04–1.0; p = 0.05.

Conclusion
This study represents a replication study of candidate SNPs associated with developing NODAT and implicates mTOR as the central regulator via altered insulin sensitivity, pancreatic β cell, and mitochondrial survival and dysfunction as evidenced by the five SNPs.

General significance
1) Highlights the importance of careful biochemical phenotyping with oral glucose tolerance tests to diagnose NODAT in reducing time to diagnosis and missed cases.
2)This alters potential genotype:phenotype association.
3)The replication study generates the hypothesis that mTOR signalling pathway may be involved in NODAT development.

Burden of fungal disease in Ireland

Our objective was to estimate the burden of fungal disease on the island of Ireland, as part of a coordinated project estimating the global burden. Published epidemiology data describing fungal infection in Ireland were identified. Population and underlying disease data were collected for 2010 and a structured set of assumptions were applied to estimate burden of fungal disease based on immunosuppression, chronic disease, and other demographic information indicating predisposition to fungal infection. From Ireland’s population of 6.4 million, we estimate 117 000 patients develop significant fungal disease each year. By far the most common fungal disease is recurrent Candida vaginitis, with an estimated 95 000 episodes annually (3000 per 100 000 women). Other fungal diseases which may be less well recognized are severe asthma with fungal sensitization and allergic bronchopulmonary aspergillosis, with estimated episodes per year of 11 700 and 9000, respectively (182 and 140 per 100 000 population, respectively). The model also estimates 450 episodes of invasive aspergillosis, 200 of chronic pulmonary aspergillosis, 600 of oesophageal candidiasis and 450 of candidaemia per year (7, 3, 9 and 6 episodes per 100 000 population, respectively). This is, we believe, the first attempt to estimate the burden of fungal disease in our population and provides a basis for estimating its impact on human health and resource use.

Marrow aplasia developing 13 years after HLA-identical sibling allogeneic transplantation for chronic myeloid leukaemia:successful treatment with antithymocyte globulin and peripheral blood stem cell infusion from the original donor

Secondary or late graft failure has been defined as the development of inadequate marrow function after initial engraftment has been achieved. We describe a case of profound marrow aplasia occurring 13 years after sibling allogeneic bone marrow transplantation for chronic myeloid leukaemia (CML) in first chronic phase. Although the patient remained a complete donor chimera, thereby suggesting that an unselected infusion of donor peripheral blood stem cells (PBSC) or bone marrow might be indicated, the newly acquired aplasia was thought to be immune in aetiology and some immunosuppression was therefore considered appropriate. Rapid haematological recovery was achieved after the infusion of unselected PBSC from the original donor following conditioning with anti-thymocyte globulin (ATG).