Seroprevalence of a "new" bacterium, Simkania negevensis, in renal transplant recipients and in hemodialysis patients.

BACKGROUND: Simkania negevensis is an obligate intracellular bacterium belonging to the family Simkaniaceae in the Chlamydiales order. It is considered an ubiquitous microorganism and aquatic environments may be involved as a source of infection for humans. It was just isolated in samples from domestic water supplies and from mains water supplies, like spa water or swimming pool water, confirming its ability to resist to the common chlorination treatments. Evidence indicates a possible role of the microorganism in respiratory tract infections, in gastroenteric disorders and in the pathogenesis of cardiovascular disease, furthermore it has hypothesized that it could play a role in lung transplant rejection. Prevalence and possible effects in nephrology are unknown. METHODS: We examined the occurrence of Simkania negevensis in two differents populations, both characterized by a high susceptibility to infectious complications: 105 hemodialysis patients, 105 renal transplant recipients and 105 healthy subjects through the IgG and IgA response to Simkania negevensis in their sera. Serum antibodies to Simkania negevensis were detected by a homemade ELISA performed according to the Kahane's protocol. Furthermore water samples from hemodialytic circuit were collected, to evaluate Simkania negevensis resistance to usual treatment of disinfection. RESULTS: Our results were unexpected, showing a higher seroprevalence of antibodies against Simkania negevensis in the hemodialysis patients, compared to renal transplant patients (IgG 22% vs 9% - IgA 9% vs 3%). S. negevensis was isolated in all water samples analyzed. CONCLUSIONS: Our study detected for the first time the occurrence of S. negevensis in hemodialysis and in renal transplant patients. Our findings suggest that water used in hemodialysis could be one of the possible sources of S. negevensis infection, without clinical involvement risk for patients.

Severe Milk-Alkali Syndrome in a Patient with Hypoparathyroidism Associated with 1,25(OH)2D, Hydrochlorothiazide and Anthranoid Laxative Consumption.

BACKGROUND: Milk-alkali syndrome is a life-threatening condition defined by the triad of hypercalcaemia, metabolic alkalosis and acute renal failure, and is associated with consumption of calcium and absorbable alkali. METHODS: We report the case of a patient admitted to a step-down unit of a large hospital in Italy. RESULTS: The patient was a 59-year-old woman with hypoparathyroidism and mild chronic kidney insufficiency, treated for a preceding episode of hypocalcaemia with high doses of calcitriol and calcium carbonate, who was also taking hydrochlorothiazide and unreported herbal anthranoid laxatives. The patient was admitted to hospital with severe hypercalcaemia, severe metabolic alkalosis and acute renal insufficiency. The patient was successfully treated with urgent dialysis, loop diuretics and calcitonin administration. CONCLUSIONS: This case underlines the need for caution when treating patients with impaired calcium metabolism regulation, and suggests that herbal anthranoid laxatives might act as triggers for milk-alkali syndrome. LEARNING POINTS: Patients with hypoparathyroidism are more prone to develop milk-alkali syndrome.Patients need careful follow-up and review of their need for calcium supplements.Non-prescription and complementary medicines can aggravate hypercalcaemia.

Hematopoietic Cell and Renal Transplantation in Plasma Cell Dyscrasia Patients.

Gammopathies, multiple myeloma, and amyloidosis are plasma dyscrasias characterized by clonal proliferation and immunoglobulin overproduction. Renal impairment is the most common and serious complication with an incidence of 20-30% patients at the diagnosis. Kidney transplant has not been considered feasible in the presence of plasma dyscrasias because the immunosuppressive therapy may increase the risk of neoplasia progression, and paraproteins may affect the graft. However, recent advances in clinical management of multiple myeloma and other gammopathies allow considering kidney transplant as a possible alternative to dialysis. Numerous evidence indicates the direct relationship between hematological remission and renal function restoring. The combination of kidney and hematopoietic cell transplant has been reported as a promising approach to reestablish end-organ function and effectively treat the underlying disease. This review describes current protocols used to perform kidney transplantation in patients with plasma dyscrasias.

[Kidney Transplantation and inborn errors of metabolism]. / Trapianto renale nelle malattie da errori congeniti del metabolismo.

Inherited kidney diseases constitute at least 150 different disorders and they have an overall prevalence of about 6080 cases per 100,000 in Europe and in USA. At least 10% of adults and nearly all children who progress to renal-replacement therapy have an inherited kidney disease, representing the fifth most common cause of end-stage renal disease after diabetes, hypertension, glomerulonephritis, and pyelonephritis. These conditions include both structural and functional disorders, among which are counted diseases resulting from inborn errors of metabolism (IEM). Some inborn errors of metabolism primarily affect kidney and because of progress in renal replacement therapy, patients with inherited kidney disorders rarely die when their disease progresses and can live for many years. However, these patients often have compromised health with a poor quality of life. Renal transplantation offers a viable treatment option for those inborn errors of metabolism characterized by primary renal damage caused by dysfunction of a mutated protein, as in cystinuria. In this case, the indication to renal transplantation makes it possible to overcome the specific enzyme defect. However this option remains valid even when the genetic defect is expressed systemically and renal involvement is just one of the clinical manifestations of the disease, as in Anderson-Fabry disease, cystinosis, hereditary amyloidosis and primary hyperoxaluria. In these conditions, renal transplantation is combined with the liver (primary hyperoxaluria) or cardiac transplant (familial amyloidosis) improving the quality and life expectancy of patients.

[Kidney Transplantation and inborn errors of metabolism]. / Trapianto renale nelle malattie da errori congeniti del metabolismo.

Inherited kidney diseases constitute at least 150 different disorders and they have an overall prevalence of about 6080 cases per 100 000 in Europe and in USA. At least 10% of adults and nearly all children who progress to renal-replacement therapy have an inherited kidney disease, representing the fifth most common cause of end-stage renal disease after diabetes, hypertension, glomerulonephritis, and pyelonephritis. These conditions include both structural and functional disorders, among which are counted diseases resulting from inborn errors of metabolism (IEM). Some inborn errors of metabolism primarily affect kidney and because of progress in renal replacement therapy, patients with inherited kidney disorders rarely die when their disease progresses and can live for many years. However, these patients often have compromised health with a poor quality of life. Renal transplantation offers a viable treatment option for those inborn errors of metabolism characterized by primary renal damage caused by dysfunction of a mutated protein, as in cystinuria. In this case, the indication to renal transplantation makes it possible to overcome the specific enzyme defect. However this option remains valid even when the genetic defect is expressed systemically and renal involvement is just one of the clinical manifestations of the disease, as in Anderson-Fabry disease, cystinosis, hereditary amyloidosis and primary hyperoxaluria. In these conditions, renal transplantation is combined with the liver (primary hyperoxaluria) or cardiac transplant (familial amyloidosis) improving the quality and life expectancy of patients.

Hypoacusia and chronic renal dysfunction: new etiopathogenetic prospective.

The oto-renal axis describes the relationship between hearing loss and chronic nephropathy. Several clinical studies have investigated the incidence of hypoacusia in patients affected by chronic renal failure, but the etiopathogenic mechanism is not fully understood. In this context, there is a general agreement that hypoacusia is usually neurosensorial and the cochlea is the main site of lesion. Inner ear and kidney present an interesting similarity in terms of structure and function. In particular, the presence of pericytes and podocytes in inner ear and in glomeruli, respectively, evidence common characteristics of microcirculation. Defects in microcirculation in the inner ear mainly cause an electrolytic imbalance with the consequent impairment of endocochlear potential and sensorial transduction. In kidney, microvessels and podocytes contribute to glomerular stability and function. Microcirculation dysfunction often occurs during the inflammatory status, frequently reported both in chronic nephropathy and in cardiovascular disease. Clinical studies aimed to describe the hypoacusia in nephropathy patients are summarized. Then, in order to speculate the etiopathogenic mechanism of hearing loss in chronic nephropathy, we report the similarities between pericytes and podocytes in inner ear and glomeruli microcirculation in terms of structure and function. Finally, we propose a model in which inflammation plays an important role in oto-renal dysfunction. Our model proposes the inflammation, as an etiopathogenic mechanism of hypoacusia in chronic nephropathy and the defective cross-talk between pericytes/podocytes and vascular endothelium, as the initial event of the degenerative process.

The impact of apoptosis and inflammation gene polymorphisms on transplanted kidney function.

BACKGROUND: The progressive deterioration of kidney allograft function leads in most cases to transplant failure. Polymorphisms in genes encoding for inflammatory and apoptosis molecules may be one possible explanation for interindividual differences in kidney transplant outcomes. The objective of our work was to identify the possible effect of interleukin 6 (IL-6), transforming growth factor beta 1 (TGFB1), and Fas on graft function. MATERIAL AND METHODS: A case-control study was carried out to assess potential associations between polymorphisms in inflammation- and apoptosis-related genes and the risk for chronic impairment of kidney graft function. The study included 376 cadaveric kidney recipients, 256 of them with stable graft function and 120 who experienced renal deterioration during the follow-up period of 2.6 ± 1.4 years. Genotyping of IL-6/G-174C, TGFB1/L10P, TGFB1/R25P, and Fas/G-670A polymorphisms was performed by PCR-RFLP and direct sequencing. RESULTS: Considering the single IL-6, TGFB1, and Fas polymorphisms, we found similar allelic and genotype frequencies between the 2 groups. To test the hypothesis of mutual effects of polymorphisms, multiple logistic regression was performed incorporating data for all the possible dual genotypic associations. The association of IL-6 high producer and Fas low producer genotype resulted in a protective effect against graft dysfunction (OR=0.79; 95% C.I.=0.72-0.86). CONCLUSIONS: This study did not find significant associations of apoptosis and inflammation gene polymorphisms with transplanted kidney function in Italian renal transplant recipients. However, our data seem to indicate that the carriage of IL-6 high producer/Fas low producer genotype has a protective effect against graft function loss.