Venous graft thrombosis in patients on peritoneal dialysis before transplantation.

BACKGROUND: It has been described that patients on peritoneal dialysis (PD) suffer from thrombotic events (vascular access, deep venous thrombosis, and graft thrombosis) more frequently after transplantation than other recipients. We analyzed the incidence of allograft thrombosis among patients transplanted in a 6-year period (January 1, 2000, to December 31, 2005) to identify etiological factors, such as inherited thrombophilia. MATERIALS AND METHODS: We performed 197 renal transplants in 189 patients, including 115 who had been on hemodialysis (HD), 44 on PD, and 30 preemptive. We recorded immunological and demographic data, studied graft and patient survivals, and evaluated the hypercoagulable state of those who experienced graft thrombosis. RESULTS: The mean age of the patients at transplantation was 49 years. There were no demographic or immunological differences between the three groups of patients, except for the number of previous blood transfusions and panel reactive antibodies (PRA) levels. Forty-seven grafts were lost in the first year; 14 suffered venous thrombosis, and there were 10 acute rejection epidoses (ARE), 7 death-censored graft failures, 3 chronic allograft nephropathies (CAN), 6 primary nonfunctions, 5 removed due to infection, 1 primary disease relapse, and 1 hemolytic-uremic syndrome. Of the 14 cases of thrombosis in 12 patients, 10 had been on PD and 4 on HD immediately before transplant. One-year graft and patient survivals were similar: 74% HD, 68% PD, 86% preemptive, and 93% HD, 95% PD, and 96% preemptive, respectively. The hypercoagulable state showed inherited thrombophilia patterns in some cases, but most of them were normal. CONCLUSION: Renal graft thrombosis was responsible for graft lost in PD patients within the first year, while in the HD group it was ARE and in the preemptive cohort, death with a functioning graft. The hypercoagulable state pretransplant should be more accurately studied to identify thrombotic factors other than those which are inherited.

Relevance of chronic kidney disease classification (K/DOQI) in renal transplant patients.

The National Kidney Foundation has developed guidelines for diagnosis and classification of chronic kidney disease (CKD) but it is not known whether they are applicable to renal transplant patients. This study analyzed the prevalence, the complications, and the influence of the CKD stage on the presence of complications in 506 stable transplant recipients. The mean age of the patients was 52.9 +/- 12 years, 34% were men, and the mean time after transplantation was 9.56 +/- 6.18 years. CKD was present in 90.3% with 9.9% were in CKD stages 4 or 5 with glomerular filtration rates lower than 30 mL/min per 1.73 m(2). The prevalence of anemia, phospho-calcium metabolism disorders, hypertriglyceridemia, and hypertension increased with the stage of CKD. We concluded that CKD and the complications of CKD were highly prevalent in renal transplant recipients. The classification of renal transplant patients by CKD stage may help clinicians to identify patients at increased risk and to target appropriate therapy to improve outcomes.

Impact of HLA antibodies on transplant glomerulopathy.

The influence of humoral rejection on the development of chronic allograft nephropathy (CAN) is controversial, especially in relation to transplant glomerulopathy. The aim of our study was to analyse the influence of anti-HLA antibodies on the development of transplant glomerulopathy (cg0, cg1, cg2, and cg3; Banff'97). We selected all renal transplants patients from 1975 to 2003 who had a functioning graft for at least 6 months and a clinically indicated graft biopsy with CAN and chronic glomerular changes (case group). We studied the presence of anti-HLA antibodies (Ab) in the last serum taken while the graft was functioning and divided them into three groups according to the severity of glomerular lesions. We also selected 52 contemporary and comparable cases without transplant glomerulopathy (control group). A total of 77 case had transplant glomerulopathy: 39 cg1, 29 cg2, and 9 cg3. Pretransplant Ab titers and number of previous blood transfusions were higher among the subgroup with the most severe glomerulopathy. Patients who developed posttransplant anti-HLA Ab more frequently showed transplant glomerulopathy. Serum creatinine and proteinuria were higher among cases with chronic glomerulopathy, and more grafts were lost in that group. Thus, the presence of HLA-Ab is a key factor in the development of transplant glomerulopathy and chronic allograft rejection.

A randomized trial of the efficacy and tolerability of the COX-2 inhibitor rofecoxib vs ibuprofen in patients with osteoarthritis. Rofecoxib/Ibuprofen Comparator Study Group.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). It is not known whether a specific inhibitor of COX-2 will provide efficacy in osteoarthritis (OA) comparable with NSAIDs. Therefore, we compared the efficacy and safety of the rofecoxib, which specifically inhibits COX-2, with those of the NSAID ibuprofen in patients with OA. OBJECTIVE: To compare the clinical efficacy and tolerability of rofecoxib (12.5 and 25 mg once daily) with ibuprofen (800 mg 3 times daily). METHODS: A randomized, double-blind trial of 809 adults with OA was conducted. Patients with OA in whom the knee or hip was the primary source of pain were randomized to 1 of 4 treatment groups on demonstration of disease activity: placebo; rofecoxib, 12.5 or 25 mg once daily; or ibuprofen, 800 mg 3 times daily. Clinical efficacy and safety were monitored during a 6-week treatment period. RESULTS: Both doses of rofecoxib demonstrated efficacy clinically comparable with ibuprofen as assessed by 3 primary end points (pain walking on a flat surface [Western Ontario and McMaster Universities Osteoarthritis Index], patient global assessment of response to therapy, and investigator global assessment of disease status) according to predefined comparability criteria. Both rofecoxib doses and the ibuprofen dose provided significantly (P<.001) greater efficacy than placebo on all primary end points. Results from secondary end points were consistent with those of the primary end points. All treatments were well tolerated; the overall incidence rates of clinical adverse experiences were not significantly different (P>.05) among the treatment groups. CONCLUSION: Rofecoxib was well tolerated and provided clinical efficacy comparable with a high dose of the NSAID ibuprofen.

[Microscopic polyangiitis in a patient with rheumatoid arthritis]. / Poliangeítis microscópica en paciente con artritis reumatoide.

Rheumatoid arthritis (RA) is a systemic disorder that primary involves joints, although renal disease has also been associated it is not common that rapidly progressive glomerulonephritis (RPGN) appears. We report the case of a patient with nodular and aggressive RA who had an acut renal failure secondary to ANCA positive RPGN due to a Microscopic polyangiitis who was not responsive to steroids and cyclophosphamide therapy.

HLA-DRB and HLA-DQB loci in the genetic susceptibility to develop glaucoma in Mexicans.

PURPOSE: Glaucoma is a clinically heterogeneous disease with a pathophysiology that may include genetic susceptibility, possibly associated with an immunologic disorder. The aim of this study was to determine whether the DNA polymorphisms located in the HLA-DRB1 and HLA-DQB1 genes show a specific association pattern in Mexican mestizo patients with primary open-angle glaucoma. METHODS: This was a cross-sectional, case-control, multicenter study. We analyzed the HLA-DRB1 and DQB1 loci of 81 Mexican mestizo nonrelated patients with primary open-angle glaucoma and 98 healthy ethnic matched control subjects. Patients were diagnosed clinically and by visual fields examination. HLA typing was performed by PCR-SSO reverse dot blot. RESULTS: We documented increased frequencies of HLA-DRB1*0301, DRB1*1101, DRB1*0701, DRB1*1402, DQB1*0302, and DQB1*0301; however, none of them were significantly different from normal control subjects. Haplotype analysis showed that the HLA-DRB1*0407-DQB1*0302 haplotype is significantly increased in patients compared with control subjects (P = .0001). CONCLUSIONS: The haplotype HLA-DRB1*0407-DQB1*0302 is common among Mexican mestizo (haplotype frequency = 0.102), and it was increased in our patients (haplotype frequency = 0.259, P = .0001). This may reflect an independent association of this haplotype with the disease as the result of linkage disequilibrium or the influence of a neighboring gene. The pathophysiology of this illness is uncertain, and further studies are needed regarding the genetic susceptibility to develop primary open-angle glaucoma.

Characterization of a potassium channel toxin from the Caribbean Sea anemone Stichodactyla helianthus.

A peptide toxin, ShK, that blocks voltage-dependent potassium channels was isolated from the whole body extract of the Caribbean sea anemone Stichodactyla helianthus. It competes with dendrotoxin I and alpha-dendrotoxin for binding to synaptosomal membranes of rat brain, facilities acetylcholine release at an avian neuromuscular junction and suppresses K+ currents in rat dorsal root ganglion neurones in culture. Its amino acid sequence is R1SCIDTIPKS10RCTAFQCKHS20MKYRLSFCRK30TCGTC35. There is no homology with other K+ channel-blocking peptides, except for BgK from the sea anemone Bunodosoma granulifera. ShK and BgK appear to be in a different structural class from other toxins affecting K+ channels.

[Clinical suspicion of vertebral osteomielitis: back pain in patients with hemodyalisis by catheter related infection]. / Sospecha clínica de osteomielitis vertebral: dolor de espalda en los pacientes con infección asociada a catéter de hemodiálisis.

The overall incidence of vertebral osteomyelitis is increasing due to, the increasing rates of bacteraemia due to intravascular devices. We report a patient with end-stage renal failure under hemodialysis by internal jugular catheters who started with back pain after several episodes of Staphylococcus aureus bacteraemia, and whose magnetic resonance imaging was showed signs suggestive of spondylodiscitis. Other 4 similar cases from our service have been analysed, thereby we can conclude the most effective treatment of vertebral osteomyelitis and/or epidural abscess is premature diagnosis of these pathologies. Magnetic resonance imaging is the most sensitive radiologic technique whom we have. Treatment of vertebral osteomyelitis must be preceded by a correct bacteriological diagnosis. Surgery plays a central role in the successful treatment and should be performed as soon as neurological problems are apparent.

[Diabetic neuropathy. Current concepts on etiopathogenesis, diagnosis, and treatment]. / Neuropatía diabética. Conceptos actuales sobre etiopatogénesis, diagnóstico y tratamiento.

Diabetic neuropathy (DN) is chronic complication which occurs in 50% of long standing diabetes mellitus. DN is a consequence of hyperglycemia probably through the following mechanisms: a) activation of aldose-reductase, intracellular sorbitol accumulation and myoinositol depletion, reduced activity of Na+/K+ATPase, loss of Na+ channels and demyelination; b) proteins glycation; c) microangiopathy; the first mechanism being the best known and the most reliable. DN may be subclinical or clinical. The main clinical picture is a peripheral, bilateral, symmetric polyneuropathy with a "socks and gloves" sensory impairment, muscular weakness, hyporeflexia, plantar ulcers and arthropathy. Less frequent syndromes are proximal motor neuropathy and mononeuropathy of cranial nerves or thoraco-abdominal roots. Diagnosis is based on clinical data, and may be sustained on impaired nerve conduction velocity, abnormal evoked somatosensory potentials, or sural nerve biopsy. These methods are highly sensitive but unspecific. Etiopathogenic treatment is based on glycemic control and aldose reductase inhibitors. Improvement in clinical, electrophysiologic and histopathologic data have been obtained with the latter. Symptomatic treatment includes carbamazepin, phenytoin, tricyclic antidepressives and a phenotiazin. Mononeuropathies tend to complete recovery in less than 6 months. Polyneuropathy is thought to be irreversible and progressive; however, with excellent glycemic control or with aldose reductase inhibitors nerve damage may be stabilized or even reversed.

[Nutrients in 39 Mexican coastal lagoons]. / Nutrientes en 39 lagunas costeras mexicanas.

An analysis of 39 Mexican coastal lagoons most in tropical environments, shows no nutrient limitation for primary productivity: even minimum nutrient values are higher than those of similar systems (mostly of temperate zones). In some cases, nutrient variations are large and indicative of heterogeneity. The N:P ratio is more important than simple nutrient concentrations. Using this ratio, coastal lagoons are classified as limited in nitrogen (< 5) or phosphorus (> 10).

Toxins from Physalia physalis (Cnidaria) raise the intracellular Ca(2+) of beta-cells and promote insulin secretion.

Physalia physalis is a marine cnidarian from which high molecular weight toxins with hemolytic and neurotoxic effects have been isolated. In the present work, two novel toxins, PpV9.4 and PpV19.3 were purified from P. physalis by bioactive guideline isolation. It involved two steps of column chromatography, gel filtration and RP-HPLC. The molecular weights were 550.7 and 4720.9 Da for PpV9.4 and PpV19.3, respectively. In the light of the Edman sequencing results, the structure of these toxins included the presence of modified amino acids. Both toxins increased the percentage of insulin secreting beta-cells and induced cytosolic Ca2+ elevation. To date, this is the first report of low molecular weight toxins increasing insulin secretion purified from cnidarians, by constituting a new approach to the study of beta-cells physiology.