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The role of terlipressin in hepatorenal syndrome
No full textHepatorenal syndrome (HRS) is a severe complication in patients with endstage
liver disease. It consists of functional renal vasoconstriction leading to severe
reduction of the glomerular filtration rate. In some patients the renal failure
shows a rapidly progressive course, a clinical pattern known as type 1 HRS. In
other cases the renal failure is less severe and remains stable for months, a
condition known as type 2 HRS. HRS is pathogenically related to disturbances in
circulatory function, mainly characterized by marked arterial vasodilation of the
splanchnic circulation, triggered by portal hypertension. This vasodilation may
result in effective arterial underfilling, with subsequent activation of
vasoconstrictor systems including the renin-angiotensin system and the
sympathetic nervous system, as well as hypersecretion of arginine vasopressin.
These compensatory mechanisms may lead to renal failure due to the increase in
intrarenal resistance and hypoperfusion. Although the available data are derived
from studies including a limited number of patients mainly affected by type 1
HRS, vasoconstrictor drugs, in particular the vasopressin analog terlipressin,
seem to be the most effective approach for the management of HRS. Associated with
albumin infusion, these drugs have been shown to lead to reduced mortality and
improved renal function in type 1 HRS. This is particularly true in HRS patients
awaiting liver transplantation in whom the vasoconstrictor drugs appear to be the
''bridging'' therapy of choice. Finally, their use has been shown to be safe, and
side effects usually disappear after dose reduction
Rhabdomyolysis: role of the nephrologist
No full textRhabdomyolysis is characterized by skeletal muscle necrosis resulting in release of large amounts of toxic
muscle cell components, including electrolytes, myoglobin, and other sarcoplasmic proteins into circulation.
Creatinine phosphokinase (CPK) and myoglobin serum levels constitute the diagnostic hallmark.
Nowadays, drugs have become one of the most frequent cause of rhabdomyolysis and acute kidney
injury (AKI) is a potential life-threatening complication. The mechanisms involved in the development
of AKI in rhabdomyolysis are intrarenal vasoconstriction, direct and ischemic tubule injury and tubular
obstruction. According to some clinical series, the mortality rate in patients who develop AKI due to
rhabdomyolysis is highly variable. The cornerstone in managing this condition is the early, aggressive
repletion of fluids. The composition of replacement fluid remains controversial. Saline and sodium bicarbonate,
especially in patients with metabolic acidosis, seem to be a reasonable approach. When AKI
produces refractory hyperkalemia, acidosis or volume overload, renal replacement therapy is indicated
Tenofovir and kidney transplantation: case report
No full textBackground: Hepatitis B viral
infection (HBV) has been regarded as a contraindication
for kidney transplantation because
of the high risk of viral activation induced by
immunosuppressive therapy. Anti-retroviral
drugs have changed the prognosis of patients
with hepatitis B viral infection (HBV+) who
are candidates for renal transplant; indeed,
therapy with antiretroviral drugs may ensure
lower rates of morbidity and mortality compared
to traditional therapies. Entecavir is
the first-line antiviral therapy recommended
for the treatment of HBV+ kidney-transplanted
patients. In case of resistance to entecavir,
tenofovir may be an alternative drug,
either alone or in combination with entecavir.
However, the best strategy of treatment
is still unknown. In this case-report, a HBV+
kidney-transplanted patient who presented
resistance to entecavir was initially treated
by associating tenofovir to entecavir and
with tenofovir alone afterward. This strategy
induced complete remission of viral replication.
Case presentation: In a HBV+ kidneytransplanted
patient under monotherapy with
entecavir, HBV flare (HBV DNA > 170.000
× 103 UI/mL, HBeAg+, HbeAb–) occurred
9 months after transplantation; at that time,
blood chemistry highlighted: creatinine 1.46
mg/dL, blood urea 65 mg/dL, e-GFR 50 mL/
min, proteinuria 300 mg/24 h, calciuria 2,12
mmol/24 h, phosphaturia 0.56 g/24 h, vitamin
D 11.5 ng/mL, PTH 130 pg/mL, calcemia
2.3 mmol/L, and phosphoremia 2 mg/
dL. Liver elastometry (FibroScan) showed
moderate fibrosis. Tenofovir was associated
to entecavir. Three months after the combination
therapy, reduction in HBV DNA replication
(351 × 103 UI/mL) was obtained. Creatinine
and e-GFR were 1.48 mg/dL and 52
mL/min, respectively. At this point, entecavir
was discontinued. After 13 months of tenofovir
monotherapy, complete remission of viral
replication was achieved but renal function
deteriorated and proteinuria increased
[Rhabdomyolysis: role of the nephrologist]
No full text: Rhabdomyolysis is characterized by skeletal muscle necrosis resulting in release of large amounts of toxic muscle cell components, including electrolytes, myoglobin, and other sarcoplasmic proteins into circulation. Creatinine phosphokinase (CPK) and myoglobin serum levels constitute the diagnostic hallmark. Nowadays, drugs have become one of the most frequent cause of rhabdomyolysis and acute kidney injury (AKI) is a potential life-threatening complication. The mechanisms involved in the development of AKI in rhabdomyolysis are intrarenal vasoconstriction, direct and ischemic tubule injury and tubular obstruction. According to some clinical series, the mortality rate in patients who develop AKI due to rhabdomyolysis is highly variable. The cornerstone in managing this condition is the early, aggressive repletion of fluids. The composition of replacement fluid remains controversial. Saline and sodium bicarbonate, especially in patients with metabolic acidosis, seem to be a reasonable approach. When AKI produces refractory hyperkalemia, acidosis or volume overload, renal replacement therapy is indicated
[Muscle-wasting in end stage renal disease in dialysis treatment: a review]
No full text: Progressive and generalized loss of muscle mass (muscle wasting) is a frequent complication in dialysis patients. Common uremic signs and symptoms such as insulin-resistance, increase in glucocorticoid activity, metabolic acidosis, malnutrition, inflammation and dialysis per se contribute to muscle wasting by modulating proteolytic intracellular mechanisms (ubiquitin-proteasome system, activation of caspase-3 and IGF-1/PI3K/Akt pathway). Since muscle wasting is associated with an increase in mortality, bone fractures and worsening in life quality, a prompt and personalised diagnostic and therapeutic approach seems to be essential in dialysis patients. At present, nuclear magnetic resonance (NMR), computed tomography (CT), dual-energy x-ray absorptiometry (DXA), impedance analysis, bioelectric impedance analysis (BIA) and anthropometric measurements are the main tools used to assess skeletal muscle mass. Aerobic and anaerobic training programmes and treatment of uremic complications reduce muscle wasting and increase muscle strength in uremic patients. The present review analyses the most recent data about the physiopathology, diagnosis, therapy and future perspectives of treatment of muscle wasting in dialysis patients
Vitamin D status in kidney transplant recipients: an Italian cohort report
No full textINTRODUCTION AND AIMS
Abnormal low levels of vitamin D are frequent in both general
population and in patients with chronic kidney disease.
In kidney transplant recipients, serum vitamin D levels are
reported to increase from early post-transplant period. In this
population, however, the assessment of vitamin D levels is not
routinely performed despite the pleiotropic action of the
hormone involved in both bone health control and in the
reduction of diabetes, cardiovascular disease and cancer.
Therefore, it is clinically relevant to assess calcidiol
concentration and find any potential factor which may affect its
concentration.
The aim of this cross-sectional study is to assess the levels of
serum calcidiol and find out any potential factor associated with
low calcidiol concentration in kidney transplant patients.
METHODS
132 kidney transplant recipients, followed in one nephrology
unit, were enrolled.
The analyzed variables were immunosuppressive agents,
supplementary intake of calcidiol or 1-25-dihydroxyvitamin D,
intact PTH, eGFR, serum calcium, serum phosphorus, urinary
calcium excretion, urinary phosphorus excretion, lactate
dehydrogenase, creatine phosphokinase, total protein, albumin.
On the basis of serum calcidiol levels patients were classified as
suffering from hormone insufficiency (< 30 ng/mL), deficiency
(< 20 ng/mL) or severe deficiency (<10 ng/mL). Hip and
lumbar spine BMD was measured by dual-energy X-ray
absorptiometry (DXA).
RESULTS 1
Cohort clinical characteristics and blood chemistry are listed in
Tab 1.
Primary renal diseases were: glomerulonephritis (40.9%),
ADPKD (18.2%), hypertension (3%), diabetes mellitus (4.5%),
interstitial nephritis (9.8%), other diseases (23.6%).
Mean serum calcidiol levels were 17.5±8.7 ng/mL. Vitamin D
insufficiency, deficiency and severe deficiency was observed in
19.7 %, 34.5 %, 34.1%, respectively. No differences were
observed between males (15.9±8.8 ng/mL) and females
(14.5±8,5 ng/mL), seasonal blood collections (winter/autumn
15.4±8.6 ng/mL VS summer/spring 16.0±9.6 ng/mL) or
exposure to sunlight (outdoor job 16.5±8.9 ng/mL VS indoor job
13.1±8.0 ng/mL). RESULTS 2
Only 9.8 % of the patients had normal calcidiol levels. In an
univariate analysis, calcidiol levels were associated with eGFR
(r= ,180; p=0.04), PTH (r= -,334; p=0.01), serum calcium ( r= ,
208; p=0.02) and PTH (r=−0.254, P<0.001).
On multiple regression analysis, PTH (Beta= -252; p=0.003) and
serum calcium (Beta= ,180; p=0.03) predicted levels of calcidiol/
On multiple regression analysis, levels of calcidiol were expected
with PTH (Beta= -252; p=0.003) and serum calcium (Beta= ,180;
p=0.03).
In 53% of the patients, BMD T-score from lumbar spine
(-1.48±0.95) and hip (-1.27±1.4) was considered osteopenia
according to WHO.
CONCLUSIONS
Low levels of calcidiol are very frequent in kidney transplant
patients. Less than 10% of the patients have normal serum
concentration of calcidiol. By contrast, PTH and calcium serum
concentrations influence calcidiol levels.
These findings should be taken into account in kidney transplant
recipients with low calcidiol levels, who may benefit from oral
vitamin D supplementatio
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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