Foley Follies: Emphysematous Pyelitis from Instrumentation in Obstructive Uropathy.

Emphysematous pyelitis (EP) is a subclass of a life-threatening necrotizing infection of the urinary system called emphysematous pyelonephritis (EPN). We report a case of an 81-year-old man with emphysematous pyelitis, which occurred after urinary tract instrumentation and resolved with conservative medical management. This case highlights the potential complications of urinary tract manipulation and the importance of a prompt diagnosis.

Use of continuous venovenous hemofiltration for acute renal failure due to multiple myeloma cast nephropathy.

Renal insufficiency is associated with high morbidity and mortality in multiple myeloma. One of the common causes for acute renal failure in multiple myeloma is cast nephropathy. It is important to reduce the levels of light chains to improve renal failure and also the overall outcome. Plasmapheresis has failed to show any significant improvement in renal failure due to cast nephropathy as demonstrated in a recent randomized control trial. Here, we present a case series of three patients who were treated with continuous venovenous hemofiltration as a modality to remove these free light chains. There was improvement in renal failure in these patients with decrease in the levels of free light chains. These patients remained off hemodialysis on follow-up and two of them were able to undergo hematopoietic stem cell transplantation.

Mitogen-activated protein kinase phosphorylation in kidneys of beta(s) sickle cell mice.

Previous studies in beta(s) sickle cell mice demonstrated renal immunostaining for nitrotyrosine, which is putative evidence of peroxynitrite (ONOO(-)) formation. ONOO(-) is known to nitrate tyrosine residues of various enzymes, thereby interfering with phosphorylation and inactivating them. The present study examined the state of phosphorylation of mitogen-activated protein (MAP) kinase signal transduction enzymes, i.e., p38, c-Jun NH(2)-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK). Western blot performed with antibodies directed against specific phosphorylated threonine/tyrosine residues of these enzymes demonstrated reduced phosphorylation of renal p38 and a trend toward reduced phosphorylation of ERK. In contrast, phosphorylation of renal JNK was markedly increased compared with normal mice. The abundance of MAP kinase phosphatase-1 (MKP-1), a key upstream enzyme that modulates phosphorylation of MAP kinases, was not different in beta(s) versus normal mice. To determine whether nitration of tyrosine by ONOO(-) was responsible for reduced phosphorylation of p38 and ERK, mercaptoethylguanidine (MEG), a compound known to reduce inducible isoform of nitric oxide synthase activity and to scavenge ONOO(-), was administered to beta(s) mice for 5 d. MEG was found to restore phosphorylation of p38 and ERK toward normal levels. These observations provide evidence that ONOO(-) (or closely related reaction products of NO) contributes to dephosphorylation of p38 and ERK, and presumably reduces activity of these enzymes. The increased phosphorylation of JNK, which suggests activation of this signaling pathway by extracellular stress signals, may play a role in apoptosis in the kidneys of these mice. The changes in phosphorylation of MAP kinase pathways found in this study could have important consequences for regulation of nuclear transcription factors, and thus renal function and pathology in sickle cell kidneys.