[Long-term outcome after dialysis-dependent renal failure on the intensive care unit]. / Langzeitergebnis nach akutem dialysepflichtigem Nierenversagen auf einer internistischen Intensivstation.

BACKGROUND: Acute kidney injury (AKI) is a common and serious complication of acute life-threatening diseases. OBJECTIVES: The aim of this study was to investigate the effect of acute renal failure on mortality in intensive care patients, the need for renal replacement therapy at discharge, and the effect on long-term mortality. MATERIAL AND METHODS: Evaluation of 118 patient cases with dialysis-dependent acute renal failure between November 2016 and December 2017 admitted to a medical intensive care unit (ICU) at the University Hospital Tübingen, Germany. Dialysis at discharge and 1­year mortality were defined as the primary endpoints. The secondary endpoint was need for continuous renal replacement after 18 months. RESULTS: In 118 patients, renal replacement modality by means of hemodialysis became necessary. A mortality rate of 45.8% (54/118) was found in patients requiring dialysis. Of the 64 surviving dialysis-dependent patients, 35.9% were still dependent on renal replacement therapy at the time of discharge. The 1­year mortality rate was significantly higher in patients that still required dialysis at the time of discharge (p = 0.004). At 18-month follow-up, seven patients (10.9%) were still on renal replacement therapy. At this time, dialysis was significantly more frequent in patients with dialysis at the time of discharge than in dialysis-free patients (7.1% vs. 71.4%, p = 0.001). CONCLUSION: Severe episodes of AKI requiring renal replacement therapy in the setting of an ICU are associated with increased mortality 1 year after discharge and an increased requirement for renal replacement 18 months after discharge.

Plasma kallikrein activates the epithelial sodium channel in vitro but is not essential for volume retention in nephrotic mice.

AIM: Recent work has demonstrated that activation of the epithelial sodium channel (ENaC) by aberrantly filtered serine proteases causes sodium retention in nephrotic syndrome. The aim of this study was to elucidate a potential role of plasma kallikrein (PKLK) as a candidate serine protease in this context. METHODS: We analysed PKLK in the urine of patients with chronic kidney disease (CKD, n = 171) and investigated its ability to activate human ENaC expressed in Xenopus laevis oocytes. Moreover, we studied sodium retention in PKLK-deficient mice (klkb1-/- ) with experimental nephrotic syndrome induced by doxorubicin injection. RESULTS: In patients with CKD, we found that PKLK is excreted in the urine up to a concentration of 2 µg mL-1 which was correlated with albuminuria (r = .71) and overhydration as assessed by bioimpedance spectroscopy (r = .44). PKLK increased ENaC-mediated whole-cell currents, which was associated with the appearance of a 67 kDa γ-ENaC cleavage product at the cell surface consistent with proteolytic activation. Mutating a putative prostasin cleavage site in γ-ENaC prevented channel stimulation by PKLK. In a mouse model for nephrotic syndrome, active PKLK was present in nephrotic urine of klkb1+/+ but not of klkb1-/- mice. However, klkb1-/- mice were not protected from ENaC activation and sodium retention compared to nephrotic klkb1+/+ mice. CONCLUSION: Plasma kallikrein is detected in the urine of proteinuric patients and mice and activates ENaC in vitro involving the putative prostasin cleavage site. However, PKLK is not essential for volume retention in nephrotic mice.

[Pulmonary infection in neutropenia]. / Pulmonale Infektion bei Neutropenie - Fall 1/2015.

UNLABELLED: MEDICAL HISTORY AND CLINICAL COURSE: A 42-year-old patient with hairy cell leukemia had been treated for 3 years by a hematologist in private practice. Initially the patient received 1 course of cladribine upon which the disease went into complete remission. 6 weeks ago a relapse was diagnosed and combination therapy with cladibrin and rituximab was initiated. Now the patient presented to the emergency room with shortness of breath and pain when breathing. INVESTIGATIONS, TREATMENT AND COURSE: In the chest x-ray, patchy infiltrates and pleural effusions were found on both sides. The subsequently performed computed tomography showed bilateral compactions with an Halo suspicious for fungal infiltrates. Upon admission to the hospital, an empirical antibiotic therapy with clarithromycin and piperacillin/tazobactam was initiated, which was later escalated to meropenem and linezolid. Additionally, an antifungal therapy with voriconazole was started and later switched to liposomal amphotericin B. At his admission, a positive aspergillus antigen could be detected in the microbiological laboratory. Under antimycotic treatment the aspergillus antigen was repeatedly negative. The patient presented with pronounced cytopenias and after a switch of therapy to vemurafenib and filgrastim, the hematopoiesis could only be stimulated insufficiently. The patient was transferred to the intensive care unit three days after admission with severe respiratory failure. He died on day 8 after admission. AUTOPSY AND DIAGNOSIS: Diagnosis was consistent with relapse of hairy cell leukemia with positive BRAF mutation and a bone marrow infiltration > 80 %. Autopsy revealed a significant hepato-splenomegaly, a lack of erythro-, granulo- and thrombopoiesis. Clots interspersed with fungal hyphae were found in both lungs and an infarction of the spleen with evidence of fungal hyphae was detected. The cultural findings post mortem on yeast or mold were negative. CONCLUSION: Patients with refractory hairy cell leukemia and prolonged neutropenia are at increased risk for systemic fungal infections. Therefore, prohylactic antimycotic therapy should be considered early in this group of patients. The therapeutic approach of vemurafenib in treatment-refractory hairy cell leukemia is promising and offers an additional treatment option. In the present case, the patient could unfortunately not be stabilized due to the septic complications.

Severe thrombocytopenia in hantavirus-induced nephropathia epidemica.

Nephropathia epidemica is a milder form of hemorrhagic fever with renal syndrome, caused by Puumala virus. The clinical picture is characterized by a rapid loss of renal function (acute kidney injury) and thrombocytopenia. The purpose of the current analysis was to compare the clinical course of patients presenting with or without severe thrombocytopenia. In 47 out of 456 patients with acute nephropathia epidemica, the nadir count of thrombocytes was available for the acute course of the disease. The clinical course of these patients was further analyzed. No major bleeding (e.g., intracranial bleeding or gastrointestinal bleeding) occurred in either group. Creatinine peak levels were higher and proteinuria was more frequently present in the severely thrombocytopenic group. In conclusion, severe thrombocytopenia is common in nephropathia epidemica and is associated with a more severe course of the disease; however, bleeding complications are rare.

[Punt-driver with jaundice - case 1/2014]. / Stocherkahnfahrer mit Ikterus - Fall 1/2014.

HISTORY AND ADMISSION FINDINGS: A 30-year-old student, who worked part-time as a punt-driver, was admitted to the hospital with fever up to 39.5 °C, severe pain in in his lower extremity and the lower back, nausea and jaundice. INVESTIGATIONS: Physical examination showed jaundice of skin and sclera as well as conjunctivitis of both eyes. Blood examination results indicated high levels of bilirubin (mostly conjugated), C-reactive protein and creatinine. There were no pathological findings in the ultrasound examination except of discrete splenomegaly. Serology revealed Leptospira IgM antibodies. DIAGNOSIS, TREATMENT AND COURSE: The patient was diagnosed with leptospirosis and was treated with intravenous ceftriaxon, intravenous rehydration and symptomatic analgesia. Upon this treatment, the liver and kidney function recovered and the patient could be discharged from the hospital in a good general condition. CONCLUSIONS: Leptospirosis is a zoonosis which is mainly transmitted by urine of infected animals (predominantly rodents). In this case, the disease was presumably transmitted during the patients work as a professional punt-driver on the Neckar River. The course of the disease is mostly mild with flu-like symptoms, but there are also serious courses with live-threatening complications such as liver or kidney failure and an associated high mortality rate.

[Renal failure after gastrointestinal hemorrhage: case 10/2012]. / Akutes Nierenversagen nach gastrointestinaler Blutung - Fall 10/2012.

HISTORY AND ADMISSION FINDINGS: We report on a 78-year-old female patient, who presented to the emergency department with nausea and vomiting. INVESTIGATIONS: Endoscopy of the upper gastrointestinal tract revealed gastric erosions and duodenal ulcers. The patient had iron deficiency anemia. DIAGNOSIS, TREATMENT AND COURSE: Following treatment with a proton pump inhibitor (PPI) the patient developed fever, signs of inflammation and oliguric renal failure. In the urine-dipstick there was minimal hematuria and leukocyturia. Urinary protein-differentiation revealed tubular proteinuria with excretion of α1-microglobulin. Renal biopsy showed interstitial nephritis with infiltration of eosinophilic granulocytes. After stopping treatment with PPI and commencing glucocorticoid therapy, the patient recovered fully from renal failure. CONCLUSIONS: Allergic interstitial nephritis following PPI treatment is an important differential diagnosis of renal failure of unknown cause and has a good prognosis when promptly diagnosed and treated.

[Hypercalcemic crisis in intensive care]. / Die hyperkalzämische Krise in der Intensivmedizin.

A hypercalcemic crisis is a life-threatening disease with multiorgan failure due to severe hypercalcemia. If left untreated, a hypercalcemic crisis is associated with a very high mortality and requires immediate diagnostic and therapeutic interventions. Especially a rapid rise to high calcium levels impairs the function of several organ systems and leads to central nervous, renal, cardiovascular and gastrointestinal symptoms. A hypercalcemic crisis is caused in more than 90 % by malignancy or primary hyperparathyreoidism and only in very rare cases by other diseases such as granulomatous diseases or other endocrinological diseases. Causal therapeutic options include an adequate treatment of malignancy and a surgical resection of the adenomatous tissue in primary hyperparathyreoidism. In addition, an adequate supportive therapy to lower calcium levels should be initiated as soon as possible. Rehydration with normal saline is the mainstay of therapy. Additional pharmacological therapies include biphosphonates, loop diuretics, calcitonin, steroids and calcimimetics. Besides classic hemodialysis continous renal replacement therapy with citrate anticoagulation is new therapeutical approach that can be used for the acute reduction of elevated serum calcium levels.

Exercise-induced albuminuria is associated with perivascular renal sinus fat in individuals at increased risk of type 2 diabetes.

AIMS/HYPOTHESIS: Microalbuminuria represents an established surrogate marker of early diabetic nephropathy and glomerular microangiopathy. Increasing evidence is emerging of a role of perivascular adipose tissue (PVAT) as an important link between obesity, insulin resistance and both macro- and microangiopathy. It is not known whether perivascular renal sinus fat (RSF) has an impact on microalbuminuria in the prediabetic stage. We investigated whether RSF quantified by MRI is associated with microalbuminuria before or after exercise. METHODS: Non-diabetic individuals at increased risk of type 2 diabetes were recruited into the Tübingen Lifestyle Intervention Program (TULIP); 146 participants took part in the analysis. RSF was measured in axial MRI sections at the level of the renal artery. Urine was collected before and after exercise stress testing. RESULTS: Participants (age 47 ± 12 years; mean ± SD) reached a mean exercise load of 176 ± 49 W, with a mean arterial peak pressure (MAPP) of 112 ± 14 mmHg. After adjusting for sex, age, visceral adipose tissue (VAT) and MAPP during exercise, RSF was significantly associated with postexercise albumin/creatinine ratio (ACR; p = 0.006). No association between RSF and baseline BP could be observed after adjusting for confounders (p = 0.26), and there was no association between RSF and baseline ACR either (p = 0.2). CONCLUSIONS: RSF is associated with exercise-induced albuminuria independently of sex, age, VAT and MAPP in a non-diabetic cohort at diabetic risk. We conclude that PVAT in the renal sinus may play a role in the pathogenesis of microalbuminuria.

SGK1-dependent salt appetite in pregnant mice.

AIM: Pregnancy is typically paralleled by substantial increase in maternal extracellular fluid volume, requiring net accumulation of water and NaCl. The positive water and salt balance is accomplished at least in part by increased uptake of salt secondary to enhanced salt appetite. Little is known about the underlying cellular mechanisms. Stimulation of salt appetite by mineralocorticoids, however, is known to be dependent on the serum- and glucocorticoid-inducible kinase SGK1. METHODS: To test for a role of SGK1 in the stimulation of salt appetite during pregnancy, fluid intake was recorded in pregnant SGK1 knockout mice (sgk1(-/-) ) and their wild type littermates (sgk1(+/+) ). The mice were offered two bottles, one with plain water and the other with isotonic saline. RESULTS: In early pregnancy, i.e. up to 10 days prior to parturition, the sgk1(+/+) mice displayed a significant preference for saline, whereas the sgk1(-/-) mice preferred water. Accordingly, the water intake was significantly smaller and saline intake was significantly larger in sgk1(+/+) mice than in sgk1(-/-) mice and the preference for water was significantly stronger in sgk1(-/-) mice than in sgk1(+/+) mice. Plasma aldosterone levels were higher in sgk1(-/-) mice than in sgk1(+/+) mice, a difference contrasting the enhanced salt appetite of sgk1(+/+) mice. CONCLUSIONS: SGK1 participates in the stimulation of salt appetite during pregnancy.

[Two autopsy cases with systemic amyloidosis--case 11/2010]. / Zwei Autopsiefälle mit systemischer Amyloidose--Fall 11/2010.

HISTORY AND ADMISSION FINDINGS: A 37-year old patient was admitted with upper abdominal pain, vomiting and diarrhea. A 38-year-old patient was admitted for liver failure. INVESTIGATIONS: Case 1 was diagnosed with an AL amyloidosis due to deposition of the immunoglobulin light chain kappa in all tissues analyzed. In the bone marrow plasma cells were increased to 20-30%. Case 2 suffered from AA amlyoidosis secondary to familial mediterranean fever and underwent dialysis treatment for years. He was positive for hepatitis B and C. DIAGNOSIS, TREATMENT AND COURSE: Patient 1 developed refractory nephrotic syndrome and low blood pressure. During hemodialysis circulatory failure occured and she died during resuscitation. In patient 2 a flare of chronic hepatitis B was found and treated with antiviral therapy. He was referred to ICU for rectal bleeding and developed pulmonary arrest. After resuscitation he died because of lactate acidosis and refractory circulatory failure. Both cases were subjected to autopsy. CONCLUSIONS: The vast majority (90%) of amyloidoses are due to acquired AA or AL amyloidosis. Prognosis remains poor, in particular when cardiac and vascular involvement occurs.

Simultaneous evaluation of renal morphology and function in live kidney donors using dynamic magnetic resonance imaging.

BACKGROUND: Evaluation of potential kidney donors requires the assessment of both kidney anatomy and function. In this prospective study, we sought to expand the diagnostic yield of magnetic resonance (MR) by adding functional measurements of glomerular filtration rate (GFR) and split renal function. METHODS: Between 2007 and 2009, all potential kidney donors presenting to our facility underwent a comprehensive single-stop MR study that included an assessment of anatomy, angiography and functional measurements. GFR was measured after a bolus injection of gadobutrol (4 ml, approximately 0.05 mmol/kg) and calculated from the washout of the signal intensity obtained over the liver. Split renal function was calculated from the increase of signal intensity over the renal cortex. Values were compared to renal scintigraphy with (99m)Tc-DTPA from the same day. RESULTS: The MR investigation was successfully performed in 21 participants. The GFR derived from MR (MR-GFR) correlated well (r = 0.84) with the GFR derived from scintigraphy (DTPA-GFR). The mean value of the paired differences was 4 +/- 13 [SD] ml/min/1.73 m(2) and was not significantly different from zero. The ratio between right and left kidney function was similar with both techniques (1.01 +/- 0.17 with MR and 1.06 +/- 0.12 with scintigraphy, P = 0.20). CONCLUSIONS: We demonstrate an MR-based approach to comprehensively evaluate both kidney anatomy and function in a single investigation, thereby facilitating the evaluation of potential kidney donors.

[Retroperitoneal masses: two case reports--Case 11/2009]. / Retroperitoneale Raumforderungen: Zwei Kasuistiken--Fall 11/2009.

HISTORY AND ADMISSION FINDINGS: A 35-year old patient (male, headaches, visual impairment, 170/100 mmHg, case 1) and a 61-year old patient (female, headaches, epistaxis, 230/110 mmHg, case 2) were investigated in our hospital. INVESTIGATIONS: Laboratory findings in case 1 verified acute renal failure (serum creatinine 23 mg/dl, urea 146 mg/dl, pH 7.19). Bilateral obstructive uropathy was seen in sonography, and CT showed periureteral, retroperitoneal masses (RPM). In case 2, the lab showed a marked hyperreninism with secondary hyperaldosteronism, and ultrasound revealed a lowered right renal resistance-index. The MRI showed a retroperitoneal mass with long-segmental compression of the right renal artery (no lymphomas). CT-guided biopsy revealed grade 2 adenocarcinoma. No metastases were seen in the PET-CT. DIAGNOSIS, TREATMENT AND COURSE: In case 1, Morbus Ormond with post-renal failure owing to obstructive uropathy was assumed. After drainage of obstructive uropathy, immunsuppressive therapy (glucocorticoids and azathioprine) was started, and renal function recovered completely in the patient who was free of complaints in the further clinical course. In case 2, cancer disease progressed to osteoblastic metastases under palliative chemotherapy. CONCLUSIONS: RPM generally cause symptoms at rather late stages of the underlying disease. A total of 75% of RPM are based on idiopathic retroperitoneal fibrosis (M. Ormond). Common causes of secondary RPM are drugs, neoplasms, infectious diseases and former therapies in the retroperitoneum (surgery, radiotherapy). Histological investigation is recommended for RPM with atypical location, clinical suspicion of underlying neoplastic or infectious diseases and lacking response to glucocorticoids. The standard therapy for M. Ormond includes glucocorticoids, tamoxifene or methotrexate (or combinations of glucocorticoids with either tamoxifene or methotrexate). In case of secondary RPM, therapy depends on the cause of RPM.

[Hypercalcaemic crisis and acute renal failure due to primary hyperparathyroidism]. / Hyperkalzämische Krise und akutes Nierenversagen infolge eines primären Hyperparathyreoidismus.

Hypercalcaemic crisis is a rare endocrine emergency. Often, an acute renal failure develops due to hypercalcaemia-induced polyuria. The molecular causes comprise stimulation of the calcium-sensing receptor in the ascending Henle loop and a reduced aquaporin expression in the collecting ducts. We report on a 54-year-old woman who was admitted for hypercalcaemic crisis and acute renal failure. Immediate rehydratation, bisphosphonate administration, and slow-extended daily dialysis (SLEDD) were initiated leading to a marked reduction of serum calcium. Endocrine work-up revealed primary hyperparathyroidism due to a parathyroid adenoma, which was treated by emergency surgery. Haemodialysis was continued in the first post-operative weeks for prolonged acute renal failure.

[Nephrogenic systemic fibrosis]. / Nephrogene systemische Fibrose.

Nephrogenic systemic fibrosis (NSF) is a novel disease entity, increasingly diagnosed over the last years in patients with renal functional impairment and chronic kidney disease. Recently, gadolinium-containing MR contrast agents have been causally associated with the development NSF. Herein, we present the case of a dialysis-dependent young patient with systemic lupus erythematodes, who developed disabling cutaneous sclerosis of extremities, abdomen and mammae. Clinical and laboratory investigations revealed no signs of activity of the underlying disease. Histopathological examination of a skin biopsy was consistent with NSF showing profound thickening of tissue septae with mucine deposition and slight fibroblast proliferation without inflammatory reaction. Analysis of the patient's medical history revealed that she had undergone repeated contrast enhanced MR scans, including MR angiographies with high doses of gadopentetate. UV phototherapy was little effective, and not until kidney transplantation two years later with good allograft function, improvement of clinical symptoms was observed. Discussion of this case summarizes the current knowledge of clinical features and pathogeneses of NSF, including the role of gadolinium-containing contrast agents. Evolving clinical implications are summarized in the current Tübingen University Hospital guideline for the use of contrast-enhanced MR scans in patients with impaired renal function.

[Nephropathia epidemica as the result of a Puumala virus infection in a pregnant patient]. / Nephropathia epidemica als Folge einer Puumala-Virus-Infektion bei einer schwangeren Patientin.

HISTORY AND ADMISSION FINDINGS: A 29-year-old woman in the early stage of pregnancy ( approximately 6 (th) week) presented in our hospital with influenza-like symptoms of fever, headache, aching limbs and tenderness over the costovertebral angle. Acute oliguric renal failure occurred within a few days. INVESTIGATIONS: Ultrasonography revealed symmetrically enlarged kidneys with a small amount of perirenal fluids. The blood count showed thrombocytopenia, and viral serology verified a recent infection with Puumala virus (species of Hantavirus). TREATMENT AND COURSE: Epidemic nephropathy was diagnosed. The patient underwent one session of hemodialysis and soon recovered without any residual renal damage. The pregnancy continued without any further complications. CONCLUSIONS: There are only few reports on infections with Puumala virus during pregnancy are. None of theses described any fetal abnormalities causes by the maternal infection, as in our patient. Hantavirus infections should be considered in differential diagnosis of acute renal failure in endemic regions.

Improved estimation of GFR by serum cystatin C in patients undergoing cardiac catheterization.

Clinical assessment of glomerular filtration rate (GFR) mainly relies on single determinations of serum creatinine (crea) which is commonly insensitive to mild renal dysfunction. Serum cystatin C (cysC) has been proposed as an alternative endogenous marker of GFR showing higher correlation to standard clearance methods such as inulin or iohexol clearance. We compared serum crea and cysC levels in n=127 patients undergoing cardiac catheterization. The clearance of the iodinated contrast dye iopromide served as reference method for GFR. Serum cysC was determined by a particle-enhanced immunonephelometric method. CysC showed higher non-parametric correlation (r=0.805) to the iopromide clearance compared to crea (r=0.652) and to the estimated GFR according to the Cockcroft-Gault formula (r=0.690), which underestimated true GFR systematically. Receiver operating curves revealed a greater area-under-the-curve (AUC) for cysC (0.957 vs. 0.801, p<0.05). At a cut-off level of >1.3 mg/l cysC exhibited an 88% sensitivity and a 96% specificity for detecting renal dysfunction which was defined as an iopromide clearance less than 80 ml/min/1.73 m2; best values for crea were 63% for sensitivity and 80% for specificity at a cut-off of >1.2 mg/dl. In conclusion, cysC detected reduced GFR more reliably and at an earlier stage in patients undergoing cardiac catheterization allowing a better identification of patients with renal dysfunction and those at risk for contrast damage.