[Staphylococcus-associated glomerulonephritis without IgA deposits: a case report].

Staphylococcus-associated glomerulonephritis (SAGN) represents a possible version of parainfectious glomerulonephritis and is a pathological entity that's now constantly increasing in developed countries. It is known how bacterial infections can be a possible trigger for various type of glomerulonephritis with clinical onset and evolution comparable to the ones observed in parainfectious glomerulonephritis. Furthermore, in clinical practice the identification and isolation of the pathogenic microorganism responsible for the development of parainfectious glomerulonephritis is not always possible. Therefore, in those cases in which SAGN is suspected, it is often necessary to recur to kidney biopsy in order to come to as much as possible correct diagnosis. Historically, according to scientific literature, the most distinctive anatomopathological feature of SAGN is represented by predominant or codominant mesangial IgA deposits, sometimes associated with C3 deposits. These findings make the differential diagnosis between SAGN and IgA nephropathy often necessary. However, many reports describe how SAGN can also be characterized by a varying spectrum of immunological deposits. In some cases, for example, IgA deposits can be absent and in some other cases it is described a net dominance of C3 deposits. In this case, it becomes extremely important to exclude a possible occurrence of C3 glomerulopathy (C3GN), considering how different are the therapeutic approach and the prognostic implications associated to it. However, the differential diagnosis between SAGN and C3GN can be very hard. Here's a case report about a patient who has been hospitalized into our Unit after developing a form of Staphylococcus Aureus associated glomerulonephritis which presented atypical anatomopathological features.

[Kidney involvement in Waldenström's disease - case report].

Waldenström's disease is a rare haematological neoplasm involving B lymphocytes, characterized by medullary infiltrated lymphoplasmacytic lymphoma and by the presence of a monoclonal M paraprotein. Although rarely, this condition may lead to heterogeneous renal involvement and cause severe renal failure. We report the clinical case of a patient with overt nephrotic syndrome in Waldenström's disease treated with a combination chemotherapy (rituximab, cyclophosphamide, dexamethasone) until complete renal and haematological remission.

[Diabetes after Kidney Transplantation]. / Il diabete dopo trapianto di rene.

Abnormal glucose metabolism is one of the most important complication encountered after renal transplantation. Besides the well-known type 2 diabetes mellitus, there are other two abnormal conditions that must be mentioned, high fasting plasma glucose and impaired glucose tolerance. The last one is often misdiagnosed because it needs an oral glucose tolerance (OGT), rarely used in clinical practice. The 15-30% of patients on waiting list of renal transplantation have impaired glucose tolerance. Therefore OGT should be performed in non-diabetic patients and when glycosylated hemoglobin is > 5.8 %. At 1 year after renal transplantation, about 15% of patients develops de novo diabetes, 28% after 3 years. Besides traditional risk factors, a primary role is played by immunosuppressive drugs because they reduce both the synthesis and peripheral activity of insulin. Hence the therapy of diabetes after renal transplantation must look at the cautious management of immunosuppressive therapy, in particular of the drugs like corticosteroids and tacrolimus. In most cases, either reducing or weaning these drugs can help us to achieve an improving of glucose metabolism.

[Genetics and nosological classification of renal cystic diseases]. / Genetica e nosografia delle malattie renali cistiche.

Renal cystic diseases are the major group of inherited renal disorders in humans and a leading cause of end-stage renal disease. Dominant and recessive polycystic kidney disease (ADPKD and ARPKD, respectively) account for most of the clinical conditions. However, nephronophthisis (NPHP), medullary cystic kidney disease (MCKD), and dominant glomerulocystic kidney disease (GCKD) still have a relevant clinical impact, particularly in children. The discovery that the proteins that are defective in ADPKD and ARPKD localize to the primary cilium and the recognition of the role of this organelle in cystogenesis have led to the term ''ciliopathies''. In the last decade, the list of ciliopathies has continued to grow. Analysis of the protein products of the nine NPHP genes (NPHP 1-9) evinced a strong relation between ciliary function and pathogenesis of NPHP. The oral-facial-digital syndrome (OFD) type I, characterized by congenital malformations and cystic kidney disease, was found to result from mutations in the OFD1 gene, which encodes a protein located to the primary cilium. Parallel to these advances, mutations in UMOD, the gene encoding uromodulin, were identified in pedigrees with MCKD2, familial juvenile hyperuricemic nephropathy, and autosomal dominant GCKD. In all these disorders, uromodulin was found to be accumulating in intracellular aggregates, suggesting a common pathogenesis. Taken together, these findings suggest the need for the separation of renal cystic diseases due to UMOD mutations (uromodulin-associated diseases) from renal cystic diseases related to mutation of genes encoding for proteins expressed in the primary cilium (ciliopathies).