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AIM: To discuss the overlapping clinical spectrum of encephalopathy due to Addison's disease and HIV infection. PATIENT: We report a 2.5-year-old boy from Uzbekistan with recurrent episodes of encephalopathy and seizures, triggered by infection or vaccinations, in whom adrenal insufficiency and infection with HIV and HCV was diagnosed. Presumably, Addisonian crises prompted hypovolemic shock and blood transfusions, which were responsible for horizontal HIV infection. The combination of adrenal insufficiency and HIV infection eventually led to progressive severe encephalopathy. Despite highly active antiretroviral therapy (which led to substantial reduction of blood viral load), the neurological condition did not improve. DISCUSSION: The interactions of Addison's disease and HIV in the pathogenesis of encephalopathy are discussed.

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In multiple sclerosis (MS) and its animal model, experimental allergic encephalomyelitis (EAE), clinical disease is associated with infiltration of the central nervous system (CNS) by immune cells. Subsequent remission with remyelination has been linked to an increased occurrence of oligodendrocyte progenitor (O2A) cells. Platelet-derived growth factor (PDGF) and fibroblast growth factor-2 (FGF-2) are key growth factors for O2A cells, yet little is known about their relevance in EAE and MS. We analyzed the expression of PDGF, FGF-2, and their receptors by peripheral-blood leukocytes (PBLs) and lymphocyte subsets during MBP-induced EAE. Strong up-regulation of PDGF, but not FGF-2, was observed in PBLs, with the highest expression after the disease maximum. T, NK, and NKT cells expressed PDGF, which is a novel observation because thus far only monocytes/macrophages have been reported to express PDGF. These results extend the idea that growth factors may contribute to improved CNS tissue repair, including PDGF, which is secreted by lesion-homing immune cells. The production of PDGF by lymphocytes may have potential therapeutic value when activating or modulating T-cell responses in demyelinating diseases.

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BACKGROUND: Antigen-specific immunoadsorption combined with rituximab offers the possibility for ABO-incompatible kidney transplantation without splenectomy. PATIENT AND METHOD: An 8-year-old mentally retarded girl with steroid-resistant nephrotic syndrome and focal segmental glomerulosclerosis due to mitochondriopathy poorly tolerated hemodialysis. Paternal blood group A1B was incompatible with blood group B of the child. Therefore, we decided to perform the first ABO-incompatible renal transplantation in a child in Germany using antigen-specific immunoadsorption. Rituximab (1 x 375 mg/m2) was administered 2 weeks before the first immunoadsorption (Glycosorb) ABO A-column). Triple-drug immunosuppression (tacrolimus, mycophenolate mofetil and prednisolone) was simultaneously started with immunoadsorption. Initial tacrolimus levels were targeted between 15 and 20 ng/ml. Before transplantation, six immunoadsorptions were applied on days -9, -7, -4, -3, -2 and -1. Intravenous immunoglobulin (0.5 g/kg) was administered preoperatively. After transplantation, three immunoadsorptions were performed on days +4, +6 and +8. RESULTS: Before transplantation, antibody (Ab) titers against paternal erythrocytes (20 degrees C) were reduced from 1 : 64 to 1 : 4 by six antigen-specific immunoadsorptions. After transplantation, we performed three more immunoadsorptions and the Ab titers were stable between 1 : 1 and 1 : 8. One, 2 and 8 months later we observed increases in the Ab titer up to 1 : 32 requiring no change in immunosuppressive therapy. No side effects of immunoadsorption were observed. The girl had excellent initial graft function with a serum creatinine of 55 to 70 micromol/l. Two weeks after transplantation, graft biopsy showed no signs of rejection; there was focal positivity for C4d only. Twelve months after transplantation, renal function was stable, with a serum creatinine of 117 micromol/l. Episodes of rejection or severe infections were absent. CONCLUSION: ABO-incompatible transplantation using antigen-specific immunoadsorption and rituximab may serve as a suitable alternative for children urgently needing renal transplantation and missing a blood group-compatible donor.

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BACKGROUND: Vascular endothelial growth factor (VEGF) exerts cytoprotective, antiapoptotic and proangiogenic effects; its synthesis is induced by hypoxia, several cytokines and histamine. The effects of histamine and the H2 receptor antagonist ranitidine on renal VEGF and IL-6 synthesis were investigated in a well-established rat model of renal ischemia/reperfusion injury. METHODS: Following 7 days of pretreatment with histamine (H group; n = 12), ranitidine (R group; n = 10) or vehicle (controls; n = 13), the left vascular pedicle was clamped for 50 min in uninephrectomized male rats and survival assessed in the different treatment groups. Additionally, renal IL-6 mRNA expression, as well as VEGF mRNA and protein abundance were measured in the three treatment groups following pretreatment only, 2 and 16 h after 50 min of renal ischemia (n = 6/group/timepoint). RESULTS: Ranitidine significantly increased, while histamine significantly decreased survival following renal ischemia. Renal IL-6 mRNA expression increased 2 h after reperfusion in all groups and decreased thereafter, with the lowest level observed in the R group. While VEGF mRNA did not change in controls, histamine increased, whereas ranitidine decreased its expression during the follow-up. Two hours after ischemia a twofold increase in renal VEGF protein abundance was observed in controls and the H group and significantly higher values were noted in the R group at this time point. A further increase in VEGF protein was only present in the H group 16 h after reperfusion. CONCLUSION: These results indicate an important role of histamine in kidney damage following renal ischemia. The beneficial effects of ranitidine were partly mediated by decreased IL-6 and VEGF mRNA expression and significant early increase in renal VEGF abundance.

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BACKGROUND: Single nucleotide polymorphisms (SNPs) have been reported to influence cytokine production. Certain cytokine high producer genotypes have been associated with an increased risk for acute rejection and chronic allograft dysfunction (CAD) after transplantation. Our study evaluates SNP distribution for transforming growth factor-beta1 (TGF-beta1), interleukin-10 (IL-10), and tumor necrosis factor-alpha (TNF-alpha) in pediatric renal transplant recipients and control individuals and correlates them to corresponding intrarenal gene expression. METHODS: SNPs for TGF-beta1 (codon 10 and 25), IL-10 (positions -1082, -819, -592) and TNF-alpha (position -308) were determined in 30 patients with stable graft function, in 75 patients with CAD, and in 173 control individuals by allele-specific polymerase chain reaction (PCR). Intrarenal cytokine gene expression was studied in 25 biopsies with chronic allograft nephropathy (CAN) and 27 normal kidney specimens by real-time reverse transcription (RT)-PCR. RESULTS: No difference in allele and genotype frequency was detected in any of the investigated groups. No correlation between genotype and intragraft cytokine gene expression was recognized in CAN patients. However, in normal kidney specimens, the low producer TGF-beta1 genotype at codon 10 was associated with significant lower TGF-beta1 mRNA expression. This association was not found for IL-10 or TNF-alpha. CONCLUSION: Our results do not support the proposition that certain specific cytokine genotypes for TGF-beta1, IL-10, and TNF-alpha are associated with CAD. Intrarenal cytokine gene expression only correlated to one TGF-beta1 SNP in normal kidney specimens. Since overall TGF-beta1 expression was higher in transplanted patients compared to controls, this suggests that SNPs may not play a significant role once the immune system is activated.

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BACKGROUND: Small children represent a challenging patient group in kidney transplantation (KTx). The aim of this study was to analyze patient and donor data influencing outcome in children that weighed <15 kg. METHODS: Sixty-eight kidneys were transplanted in 64 children that weighed <15 kg. In 44 cases, kidneys came from cadaveric donors (CAD) and in 24 cases from living-related donors (LRD). Grafts were placed transperitoneally via midline incision (n=16) or extraperitoneally to the iliac fossa (n=52). Vascular anastomoses were routinely performed to the aorta and vena cava even when the extraperitoneal approach was used. RESULTS: Vascular thrombosis was observed in two (3%), urinary leaks in five (7%), and stenosis in four (6%) patients. In six children receiving organs from adults to the iliac fossa, wound closure was performed using an absorbable mesh to avoid organ compression. Initial graft function occurred in 60 cases (88%). Frequency of initial graft function was significantly higher after KTx from LRD (100%) compared with CAD (82%). The 1-, 5-, and 10-year patient survival was 93%, 91%, and 91%, respectively, and the 1-, 5-, and 10-year graft survival was 92%, 85%, and 85%, respectively. There was no significant difference in patient and graft survival when KTx from LRD and CAD were compared. Within the CAD group, graft survival was improved using kidneys from donors >12 years compared with younger donors. CONCLUSION: Despite size discrepancy between recipients and grafts, KTx is feasible in children that weigh <15 kg by using an improved surgical technique even when adult organs are placed to the iliac fossa.

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