Synthesis of New Polyheterocyclic Pyrrolo[3,4-b]pyridin-5-ones via an Ugi-Zhu/Cascade/Click Strategy.

A diversity-oriented synthesis (DOS) of two new polyheterocyclic compounds was performed via an Ugi-Zhu/cascade (N-acylation/aza Diels-Alder cycloaddition/decarboxylation/dehydration)/click strategy, both step-by-step to optimize all involved experimental stages, and in one pot manner to evaluate the scope and sustainability of this polyheterocyclic-focused synthetic strategy. In both ways, the yields were excellent, considering the high number of bonds formed with release of only one carbon dioxide and two molecules of water. The Ugi-Zhu reaction was carried out using the 4-formylbenzonitrile as orthogonal reagent, where the formyl group was first transformed into the pyrrolo[3,4-b]pyridin-5-one core, and then the remaining nitrile group was further converted into two different nitrogen-containing polyheterocycles, both via click-type cycloadditions. The first one used sodium azide to obtain the corresponding 5-substituted-1H-tetrazolyl-pyrrolo[3,4-b]pyridin-5-one, and the second one with dicyandiamide to synthesize the 2,4-diamino-1,3,5-triazine-pyrrolo[3,4-b]pyridin-5-one. Both synthesized compounds may be used for further in vitro and in silico studies because they contain more than two heterocyclic moieties of high interest in medicinal chemistry, as well as in optics due to their high π-conjugation.

Ecology and responses to climate change of biocrust-forming mosses in drylands.

Interest in understanding the role of biocrusts as ecosystem engineers in drylands has substantially increased during the past two decades. Mosses are a major component of biocrusts and dominate their late successional stages. In general, their impacts on most ecosystem functions are greater than those of early-stage biocrust constituents. However, it is common to find contradictory results regarding how moss interactions with different biotic and abiotic factors affect ecosystem processes. This review aims to (i) describe the adaptations and environmental constraints of biocrust-forming mosses in drylands, (ii) identify their primary ecological roles in these ecosystems, and (iii) synthesize their responses to climate change. We emphasize the importance of interactions between specific functional traits of mosses (e.g. height, radiation reflectance, morphology, and shoot densities) and both the environment (e.g. climate, topography, and soil properties) and other organisms to understand their ecological roles and responses to climate change. We also highlight key areas that should be researched in the future to fill essential gaps in our understanding of the ecology and the responses to ongoing climate change of biocrust-forming mosses. These include a better understanding of intra- and interspecific interactions and mechanisms driving mosses' carbon balance during desiccation-rehydration cycles.

Ocimum campechianum Mill. from Amazonian Ecuador: Chemical Composition and Biological Activities of Extracts and Their Main Constituents (Eugenol and Rosmarinic Acid).

The essential oil (EO), the methanolic (MeOH), and the 70% ethanolic (70% EtOH) extracts obtained from the aerial parts of Ocimum campechianum Mill. (Ecuador) were chemically characterized through gas-chromatography coupled to mass spectrometry detector (GC-MS), high-performance liquid chromatography coupled to diode array-mass spectrometry detectors (HPLC-DAD-MS) and studied for their in vitro biological activity. The radical scavenger activity, performed by spectrophotometric 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, highlighted significant IC50 values for the EO, extracts and their main constituents (eugenol and rosmarinic acid). EO (and eugenol) showed noteworthy activity against Pseudomonas syringae pv. syringae and a moderate effect against clinical Candida strains, with possible synergism in association to fluconazole against the latter microorganisms. The extracts and pure molecules exhibited weak cytotoxic activity against the HaCat cell line and no mutagenicity against Salmonella typhimurium TA98 and TA100 strains, giving indication of safety. Instead, EO showed a weak activity against adenocarcinomic human alveolar basal epithelial cells (A549). The above-mentioned evidence leads us to suggest a potential use of the crude drug, extracts, and EO in cosmetic formulation and food supplements as antioxidant agents. In addition, EO may also have a possible application in plant protection and anti-Candida formulations.

Improvement of hyponatremia in cirrhosis is associated with improved complex information processing.

BACKGROUND AND AIM: Hyponatremia, a cause of brain dysfunction and risk factor for hepatic encephalopathy, is frequent in patients with advanced cirrhosis and ascites. The interdependence of liver failure and hyponatremia makes it difficult to separate the effects of each on cognitive function. The objective was to assess whether an increase in plasma sodium in patients with cirrhosis and ascites leads to an improvement in cognitive function. METHODS: This is a post-hoc analysis of 250 cirrhosis patients without overt hepatic encephalopathy randomized to receive either placebo or satavaptan, a vasopressin V2 antagonist. The exposure was plasma sodium, and the outcome was the trail-making test (TMT) parts A and B, which assesses speed of information processing, performed before the study starts and after 14 days. The results were analyzed by initial and change to final sodium concentration. RESULTS: At entry, the patients with normonatremia exhibited better results on both the TMT-A (median 56 vs 77.5 s for patients with sodium ≤ 130 mmol/L [P = 0.0059]) and the TMT-B (median 127 vs 170 s for patients with sodium ≤ 130 mmol/L [P = 0.0066]), unrelated to age. Improvement of hyponatremia was more common in patients who received satavaptan (59.7%) than placebo (18.5%). Correction of hyponatremia did not shorten the simple TMT-A but markedly improved the complex TMT-B by an average of 20 s compared with 6.5 s in those with continuing hyponatremia (P = 0.02). Liver status measures remained stable during the period reported. CONCLUSIONS: These data suggest that improvement of hyponatremia in patients with cirrhosis leads to an increase in the speed of complex information processing.

Midodrine and albumin for prevention of complications in patients with cirrhosis awaiting liver transplantation. A randomized placebo-controlled trial.

BACKGROUND & AIMS: Patients with decompensated cirrhosis on the waiting list for liver transplantation (LT) commonly develop complications that may preclude them from reaching LT. Circulatory dysfunction leading to effective arterial hypovolemia and activation of vasoconstrictor systems is a key factor in the pathophysiology of complications of cirrhosis. The aim of this study was to investigate whether treatment with midodrine, an alpha-adrenergic vasoconstrictor, together with intravenous albumin improves circulatory dysfunction and prevents complications of cirrhosis in patients awaiting LT. METHODS: A multicenter, randomized, double-blind, placebo-controlled trial (NCT00839358) was conducted, including 196 consecutive patients with cirrhosis and ascites awaiting LT. Patients were randomly assigned to receive midodrine (15-30 mg/day) and albumin (40 g/15 days) or matching placebos for one year, until LT or drop-off from inclusion on the waiting list. The primary endpoint was incidence of any complication (renal failure, hyponatremia, infections, hepatic encephalopathy or gastrointestinal bleeding). Secondary endpoints were mortality, activity of endogenous vasoconstrictor systems and plasma cytokine levels. RESULTS: There were no significant differences between both groups in the probability of developing complications of cirrhosis during follow-up (p = 0.402) or one-year mortality (p = 0.527). Treatment with midodrine and albumin was associated with a slight but significant decrease in plasma renin activity and aldosterone compared to placebo (renin -4.3 vs. 0.1 ng/ml.h, p < 0.001; aldosterone -38 vs. 6 ng/dl, p = 0.02, at week 48 vs. baseline). Plasma norepinephrine only decreased slightly at week 4. Neither arterial pressure nor plasma cytokine levels changed significantly. CONCLUSIONS: In patients with cirrhosis awaiting LT, treatment with midodrine and albumin, at the doses used in this study, slightly suppressed the activity of vasoconstrictor systems, but did not prevent complications of cirrhosis or improve survival. LAY SUMMARY: Patients with cirrhosis who are on the liver transplant waiting list often develop complications which prevent them from receiving a transplant. Circulatory dysfunction is a key factor behind a number of complications. This study was aimed at investigating whether treating patients with midodrine (a vasoconstrictor) and albumin would improve circulatory dysfunction and prevent complications. This combined treatment, at least at the doses administered in this study, did not prevent the complications of cirrhosis or improve the survival of these patients.

Warming reduces the cover, richness and evenness of lichen-dominated biocrusts but promotes moss growth: insights from an 8 yr experiment.

Despite the important role that biocrust communities play in maintaining ecosystem structure and functioning in drylands world-wide, few studies have evaluated how climate change will affect them. Using data from an 8-yr-old manipulative field experiment located in central Spain, we evaluated how warming, rainfall exclusion and their combination affected the dynamics of biocrust communities in areas that initially had low (< 20%, LIBC plots) and high (> 50%, HIBC plots) biocrust cover. Warming reduced the richness (35 ± 6%), diversity (25 ± 8%) and cover (82 ± 5%) of biocrusts in HIBC plots. The presence and abundance of mosses increased with warming through time in these plots, although their growth rate was much lower than the rate of lichen death, resulting in a net loss of biocrust cover. On average, warming caused a decrease in the abundance (64 ± 7%) and presence (38 ± 24%) of species in the HIBC plots. Over time, lichens and mosses colonized the LIBC plots, but this process was hampered by warming in the case of lichens. The observed reductions in the cover and diversity of lichen-dominated biocrusts with warming will lessen the capacity of drylands such as that studied here to sequester atmospheric CO2 and to provide other key ecosystem services associated to these communities.

Synthesis of New 5-Aryl-benzo[f][1,7]naphthyridines via a Cascade Process (Ugi-3CR/Intramolecular Aza-Diels-Alder Cycloaddition)/Aromatization.

A series of eight new 5-aryl-benzo[f][1,7]naphthyridines were synthesized in 17 to 64% overall yields via an improved MW-assisted cascade-like one pot process (Ugi⁻three component reaction/intramolecular aza-Diels-Alder cycloaddition) coupled to an aromatization process from tri-functional dienophile-containing ester-anilines, substituted benzaldehydes and the chain-ring tautomerizable 2-isocyano-1-morpholino-3-phenylpropan-1-one as starting reagents, under mild conditions. The doubly activated dienophile and the aza-diene functionalities of the eight new Ugi-adducts were exploited to perform an in situ aza-Diels-Alder cycloaddition/aromatization (dehydration/oxidation) process, toward the complex polysubstituted 5-aryl-polyheterocycles, which could be taken as starting point for further SAR studies because the benzo[f][1,7]naphthyridine is the core of various bioactive products. It is relevant to emphasize that the synthesis or isolation of benzo[f][1,7]naphthyridines containing a substituted aromatic ring in the C-5 position, has not been published before.

Effects of alfapump™ system on kidney and circulatory function in patients with cirrhosis and refractory ascites.

The alfapump system has been proposed as a new treatment for the management of refractory ascites. The system removes ascites from the peritoneal cavity to urinary bladder, producing a continuous low-volume paracentesis. The aim of the study is to investigate the effects of treatment with the alfapump™ system on kidney and circulatory function in patients with cirrhosis and refractory ascites. This was a prospective study including 10 patients with cirrhosis and refractory ascites. Primary outcomes were changes in glomerular filtration rate (GFR), as assessed by isotopic techniques, and changes in circulatory function assessed by arterial pressure, cardiac output, and activity of vasoconstrictor systems. Secondary outcomes were the need for large-volume paracentesis and adverse events. Follow-up was 1 year. GFR decreased significantly from 67 mL/minute/1.73 m2 (41-90 mL/minute/1.73 m2 ) at baseline to 45 mL/minute/1.73 m2 (36-74 mL/minute/1.73 m2 ) at month 6 (P = 0.04). Mean arterial pressure and cardiac output did not change significantly; however, there was a marked increase in plasma renin activity and norepinephrine concentration (median percent increase with respect to baseline +191% and 59%, respectively). There were 68 episodes of complications of cirrhosis in 8 patients during follow-up, the most frequent being acute kidney injury. In conclusion, treatment with alfapump™ system was associated with marked activation of endogenous vasoconstrictor systems and impairment of kidney function. The chronological relationship observed between kidney impairment and vasoconstrictor systems activation after device insertion suggests a cause-effect relationship, raising the possibility that treatment with alfapump impairs effective arterial blood volume mimicking a postparacentesis circulatory dysfunction syndrome. In this context, the potential role of albumin in counteracting these effects should be investigated in future studies. Liver Transplantation 23 583-593 2017 AASLD.

An efficient Ugi-3CR/aza Diels-Alder/Pomeranz-Fritsch protocol towards novel aza-analogues of (±)-nuevamine, (±)-lennoxamine and magallanesine: a diversity oriented synthesis approach.

A rapid and efficient synthesis of a series of (±)-nuevamine, (±)-lennoxamine and magallanesine aza analogues is described. The synthetic strategy involves Ugi-3CR and two further condensation processes, aza-Diels-Alder cycloaddition and the Pomeranz-Fritsch reaction. The variation of the chain-size in aldehyde moieties provided structural diversity in only two operational reaction steps.

Type-1 hepatorenal syndrome associated with infections in cirrhosis: natural history, outcome of kidney function, and survival.

UNLABELLED: Type-1 hepatorenal syndrome (HRS) is a common complication of bacterial infections in cirrhosis, but its natural history remains undefined. To assess the outcome of kidney function and survival of patients with type-1 HRS associated with infections, 70 patients diagnosed during a 6-year period were evaluated prospectively. Main outcomes were no reversibility of type-1 HRS during treatment of the infection and 3-month survival. Forty-seven (67%) of the 70 patients had no reversibility of type-1 HRS during treatment of the infection. [Correction to previous sentence added March 10, 2014, after first online publication: "Twenty-three (33%)" was changed to "Forty-seven (67%)."] The main predictive factor of no reversibility of type-1 HRS was absence of infection resolution (no reversibility: 96% versus 48% in patients without and with resolution of the infection; P < 0.001). Independent predictive factors of no reversibility of type-1 HRS were age, high baseline serum bilirubin, nosocomial infection, and reduction in serum creatinine <0.3 mg/dL at day 3 of antibiotic treatment. No reversibility was also associated with severity of circulatory dysfunction, as indicated by more marked activity of the vasoconstrictor systems. In the whole series, 3-month probability of survival was only 21%. Factors associated with poor prognosis were baseline serum bilirubin, no reversibility of type-1 HRS, lack of resolution of the infection, and development of septic shock after diagnosis of type-1 HRS. CONCLUSION: Type-1 HRS associated with infections is not reversible in two-thirds of patients with treatment of infection only. No reversibility of type-1 HRS is associated with lack of resolution of the infection, age, high bilirubin, and no early improvement of kidney function and implies a poor prognosis. These results may help advance the management of patients with type-1 HRS associated with infections.

Urinary neutrophil gelatinase-associated lipocalin predicts kidney outcome and death in patients with cirrhosis and bacterial infections.

BACKGROUND & AIMS: Infections in cirrhosis are frequently complicated by kidney dysfunction that entails a poor prognosis. Urinary biomarkers may be of potential clinical usefulness in this setting. We aimed at assessing the value of urinary neutrophil gelatinase-associated lipocalin (uNGAL), a biomarker overexpressed in kidney tubules during kidney injury, in predicting clinical outcomes in cirrhosis with infections. METHODS: One-hundred and thirty-two consecutive patients hospitalized with infections were evaluated prospectively. Acute kidney injury (AKI) was defined according to AKIN criteria. uNGAL was measured at infection diagnosis and at days 3 and 7 (ELISA, Bioporto, DK). RESULTS: Patients with AKI (n=65) had significantly higher levels of uNGAL compared to patients without AKI (203 ± 390 vs. 79 ± 126 µg/g creatinine, p<0.001). Moreover, uNGAL levels were significantly higher in patients who developed persistent AKI (n=40), compared to those with transient AKI (n=25) (281 ± 477 vs. 85 ± 79 µg/g creatinine, p<0.001). Among patients with persistent AKI, uNGAL was able to discriminate type-1 HRS from other causes of AKI (59 ± 46 vs. 429 ± 572 µg/g creatinine, respectively; p<0.001). Moreover, the time course of uNGAL was markedly different between the two groups. Interestingly, baseline uNGAL levels also predicted the development of a second infection during hospitalization. Overall, 3-month mortality was 34%. Independent predictive factors of 3-month mortality were MELD score, serum sodium, and uNGAL levels at diagnosis, but not presence or stage of AKI. CONCLUSIONS: In patients with cirrhosis and infections, measurement of urinary NGAL at infection diagnosis is useful in predicting important clinical outcomes, specifically persistency and type of AKI, development of a second infection, and 3-month mortality.

Terlipressin and albumin for type-1 hepatorenal syndrome associated with sepsis.

BACKGROUND & AIMS: Terlipressin and albumin is the standard of care for classical type-1 hepatorenal syndrome (HRS) not associated with active infections. However, there is no information on efficacy and safety of this treatment in patients with type-1 HRS associated with sepsis. Study aim was to investigate the effects of early treatment with terlipressin and albumin on circulatory and kidney function in patients with type-1 HRS and sepsis and assess factors predictive of response to therapy. METHODS: Prospective study in 18 consecutive patients with type-1 HRS associated with sepsis. RESULTS: Treatment was associated with marked improvement in arterial pressure and suppression of the high levels of plasma renin activity and norepinephrine. Response to therapy (serum creatinine <1.5mg/dl) was achieved in 12/18 patients (67%) and was associated with improved 3-month survival compared to patients without response. Non-responders had significantly lower baseline heart rate, poor liver function tests, slightly higher serum creatinine, and higher Child-Pugh and MELD scores compared to responders. Interestingly, non-responders had higher values of CLIF-SOFA score compared to responders (14±3 vs. 8±1, respectively p<0.001), indicating greater severity of acute-on-chronic liver failure (ACLF). A CLIF-SOFA score ⩾11 had 92% sensitivity and 100% specificity in predicting no response to therapy. No significant differences were observed between responders and non-responders in baseline urinary kidney biomarkers. Treatment was safe and no patient required withdrawal of terlipressin. CONCLUSIONS: Early treatment with terlipressin and albumin in patients with type-1 HRS associated with sepsis is effective and safe. Patients with associated severe ACLF are unlikely to respond to treatment.

LEFT ventricular function assessed by echocardiography in cirrhosis: relationship to systemic hemodynamics and renal dysfunction.

BACKGROUND & AIMS: The current study aimed at assessing the potential role of cardiac abnormalities in the pathogenesis of circulatory and renal dysfunction in cirrhosis. METHODS: One hundred and fifty-two patients (34 without ascites, 95 with ascites without renal failure and 21 with hepatorenal syndrome) were evaluated using Doppler echocardiography. In 102 patients, diastolic function was assessed by measuring parameters related to ventricular filling velocity, mitral annulus velocity and left atrial dimensions. Cardiopulmonary pressures were also measured by cardiac catheterization in 54 patients. In 50 additional patients, left ventricular myocardial strain was performed to estimate myocardial contractility and systolic function. RESULTS: Grade 1 and 2 diastolic dysfunction was present in 41% and 16% of the patients, respectively. There was no patient with severe grade 3 diastolic dysfunction. Grade 2 diastolic dysfunction was associated with higher cardiopulmonary pressures but values were within the normal limits in all cases. Diastolic dysfunction directly correlated with liver failure but not with the degree of impairment in circulatory and renal function. The proportion of patients without or with grade 1 or 2 diastolic dysfunction was similar in patients with compensated cirrhosis, with ascites without renal failure or with hepatorenal syndrome despite marked differences in the degree of circulatory dysfunction, as indicated by plasma renin activity and noradrenaline concentration. The heart rate and systolic function were normal in all cases. There were no differences between patients without ascites, with ascites without renal failure or with HRS, despite marked differences in the activity of the renin-angiotensin system and sympathetic nervous system. These features indicate an impaired response of cardiac chronotropic and inotropic function to changes in systemic hemodynamics. CONCLUSIONS: These data indicates that: (1) diastolic dysfunction is frequent in cirrhosis but in most cases it is of mild degree and does not increase the cardiopulmonary pressure to abnormal levels. This feature, which may be due to the central hypovolemia of cirrhosis, probably accounts for the lack of symptoms associated with this condition. (2) Diastolic dysfunction in cirrhosis is unrelated to circulatory dysfunction, ascites and HRS. (3) In cirrhosis, there is a lack of response of the left ventricular systolic and chronotropic function to peripheral arterial vasodilation and activation of the sympathetic nervous system and this feature is an important contributory factor to the progression of circulatory dysfunction and the pathogenesis of ascites and HRS.

A modified acute kidney injury classification for diagnosis and risk stratification of impairment of kidney function in cirrhosis.

BACKGROUND & AIMS: The Acute Kidney Injury Network (AKIN) criteria are widely used in nephrology, but information on cirrhosis is limited. We aimed at evaluating the AKIN criteria and their relationship with the cause of kidney impairment and survival. METHODS: We performed a prospective study of 375 consecutive patients hospitalized for complications of cirrhosis. One-hundred and seventy-seven (47%) patients fulfilled the criteria of Acute Kidney Injury (AKI) during hospitalization, the causes being hypovolemia, infections, hepatorenal syndrome (HRS), nephrotoxicity, and miscellaneous (62, 54, 32, 8, and 21 cases, respectively). RESULTS: At diagnosis, most patients had AKI stage 1 (77%). Both the occurrence of AKI and its stage were associated with 3-month survival. However, survival difference between stages 2 and 3 was not statistically significant. Moreover, if stage 1 patients were categorized into 2 groups according to the level of serum creatinine used in the classical definition of kidney impairment (1.5mg/dl), the two groups had a significantly different outcome. Combining AKIN criteria and maximum serum creatinine, 3 risk groups were identified: (A) patients with AKI stage 1 with peak creatinine ≤ 1.5mg/dl; (B) patients with stage 1 with peak creatinine >1.5mg/dl; and (C) patients with stages 2-3 (survival 84%, 68%, and 36%, respectively; p<0.001). Survival was independently related to the cause of kidney impairment, patients with HRS or infection-related having the worst prognosis. CONCLUSIONS: A classification that combines the AKIN criteria and classical criteria of kidney failure in cirrhosis provides a better risk stratification than AKIN criteria alone. The cause of impairment in kidney function is key in assessing prognosis in cirrhosis.

Effects of intravenous albumin in patients with cirrhosis and episodic hepatic encephalopathy: a randomized double-blind study.

BACKGROUND & AIMS: Episodic hepatic encephalopathy is frequently precipitated by factors that induce circulatory dysfunction, cause oxidative stress-mediated damage or enhance astrocyte swelling. The administration of albumin could modify these factors and improve the outcome of hepatic encephalopathy. The aim of this study is to assess the efficacy of albumin in a multicenter, prospective, double-blind, controlled trial (ClinicalTrials.gov number, NCT00886925). METHODS: Cirrhotic patients with an acute episode of hepatic encephalopathy (grade II-IV) were randomized to receive albumin (1.5g/kg on day 1 and 1.0g/kg on day 3) or isotonic saline, in addition to the usual treatment (laxatives, rifaximin 1200mg per day). The primary end point was the proportion of patients in which encephalopathy was resolved on day 4. The secondary end points included survival, length of hospital stay, and biochemical parameters. RESULTS: Fifty-six patients were randomly assigned to albumin (n=26) or saline (n=30) stratified by the severity of HE. Both groups were comparable regarding to demographic data, liver function, and precipitating factors. The percentage of patients without hepatic encephalopathy at day 4 did not differ between both groups (albumin: 57.7% vs. saline: 53.3%; p>0.05). However, significant differences in survival were found at day 90 (albumin: 69.2% vs. saline: 40.0%; p=0.02). CONCLUSIONS: Albumin does not improve the resolution of hepatic encephalopathy during hospitalization. However, differences in survival after hospitalization suggest that the development of encephalopathy may identify a subgroup of patients with advanced cirrhosis that may benefit from the administration of albumin.

Changes in biocrust cover drive carbon cycle responses to climate change in drylands.

Dryland ecosystems account for ca. 27% of global soil organic carbon (C) reserves, yet it is largely unknown how climate change will impact C cycling and storage in these areas. In drylands, soil C concentrates at the surface, making it particularly sensitive to the activity of organisms inhabiting the soil uppermost levels, such as communities dominated by lichens, mosses, bacteria and fungi (biocrusts). We conducted a full factorial warming and rainfall exclusion experiment at two semiarid sites in Spain to show how an average increase of air temperature of 2-3 °C promoted a drastic reduction in biocrust cover (ca. 44% in 4 years). Warming significantly increased soil CO2 efflux, and reduced soil net CO2 uptake, in biocrust-dominated microsites. Losses of biocrust cover with warming through time were paralleled by increases in recalcitrant C sources, such as aromatic compounds, and in the abundance of fungi relative to bacteria. The dramatic reduction in biocrust cover with warming will lessen the capacity of drylands to sequester atmospheric CO2 . This decrease may act synergistically with other warming-induced effects, such as the increase in soil CO2 efflux and the changes in microbial communities to alter C cycling in drylands, and to reduce soil C stocks in the mid to long term.

[Biomarkers of acute kidney injury: a « trending topic ¼ in cirrhosis]. / Biomarcadores de insuficiencia renal: un «trending topic¼ en cirrosis.

Acute kidney injury (AKI) is an ominous event in the natural history of cirrhosis. The differential diagnosis of this entity is hampered by the absence of specific biomarkers of tubular damage in cirrhosis. The clinical usefulness of such biomarkers is determined by their effectiveness in the diagnosis of AKI and their ability to provide critical information to ameliorate clinical outcomes and survival. The lack of biomarkers has hindered the development of interventions aimed to improve the prognosis of kidney impairment in cirrhosis. Currently, biomarkers are an area of intense research in nephrology. Emerging genomic and proteomic technologies have revealed novel plasma and urinary biomarkers of AKI. The present article discusses the most promising candidate biomarkers with potential application in cirrhosis, such as NGAL, KIM-1, cystatin-C, IL-18, L-FABP, N-acetyl glucosaminidase and netrin-1, are discussed below.

Atypical Mal de Meleda in a Hispanic Patient.

Mal de Meleda (MDM) is a rare autosomal palmoplantar keratoderma (PPK) skin disorder (estimated incidence of 1 per 100,000 people) commonly associated with consanguinity and early childhood onset. MDM is characterized by bilateral diffusion of PPK plaques with delimited yellowish lesions that transgredien to the dorsum of the hands and feet. Additional features include nail dystrophy, lichenoid lesions, hyperhidrotic maceration, involvement of the knees and elbows, malodor, fungal superinfections, and digital constrictions. A male patient aged 42 years presented with asymptomatic, chronic, and diffused PPK lesions that progressed to the dorsal surface of the hands and feet, along with knees and elbows involvement. On clinical examination, asymmetrical lesions were observed on the hands, the left palm with yellowish waxy hyperkeratotic plaques, and the right palm with erythematous scaling and hyperkeratotic interphalangeal rings. The soles of the feet presented with yellow waxy hyperkeratotic plaques. In addition, nail dystrophy and loss of dermatoglyphics were observed. Initially, symptomatic topical treatment was established. However, owing to the lack of clinical response, a biopsy was performed, which revealed thickened corneal layer, acanthosis, spongiosis, and perivascular lymphohistiocytic infiltrate. MDM diagnosis was confirmed based on a personal history of consanguinity, clinical presentation with absence of systemic symptoms, and transgredien pattern of the lesions. Systemic treatment with low doses of isotretinoin (10 mg orally everyday) was initiated, and two months later, slight clinical improvement has been observed until date. The present case report describes MDM in a Hispanic patient, who presented with asymmetric PPK lesions on the hands and received isotretinoin treatment.

Tolvaptan, an oral vasopressin antagonist, in the treatment of hyponatremia in cirrhosis.

BACKGROUND & AIMS: Tolvaptan is a vasopressin V2-receptor antagonist that improves serum sodium concentration by increasing renal solute-free water excretion. Specific data on the safety and efficacy of tolvaptan in patients with cirrhosis and hyponatremia has not been exclusively evaluated. METHODS: This sub-analysis of the Study of Ascending Levels of Tolvaptan trials examined cirrhotic patients with hyponatremia who received 15 mg oral tolvaptan (n=63; increased to 30 or 60 mg if needed) or placebo (n=57) once-daily for 30 days. At baseline, 44% had mild hyponatremia (serum sodium 130-134 mmol/L), 56% had marked hyponatremia (serum sodium <130 mmol/L), 85% had cirrhosis due to alcohol and/or hepatitis B/C, and 80% were Child-Pugh class B/C. RESULTS: Tolvaptan was effective in raising serum sodium. Average daily area under the curve for serum sodium was significantly greater in the tolvaptan group from baseline to day 4 (p<0.0001) and day 30 (p<0.0001). This superiority was maintained after stratification by baseline hyponatremia (mild and marked), estimated glomerular filtration rate (≤ 60 ml/min and >60 ml/min), or serum creatinine levels (<1.5mg/dl and ≥ 1.5mg/dl). Hyponatremia recurred 7 days after discontinuation of tolvaptan. Mean mental component summary scores of the SF-12 health survey improved from baseline to day 30 in the tolvaptan group but not the placebo group (4.68 vs. 0.08, p=0.02). Major side effects due to tolvaptan were dry mouth and thirst. Gastrointestinal bleeding occurred in 10% and 2% of patients in the tolvaptan and placebo group, respectively (p=0.11). Adverse event rates, withdrawals, and deaths were similar in both groups. CONCLUSIONS: One month of tolvaptan therapy improved serum sodium levels and patient-reported health status in cirrhotic patients with hyponatremia. Hyponatremia recurred in tolvaptan-treated patients after discontinuation.

Albumin for bacterial infections other than spontaneous bacterial peritonitis in cirrhosis. A randomized, controlled study.

BACKGROUND & AIMS: Treatment with albumin in patients with cirrhosis and spontaneous bacterial peritonitis (SBP) prevents renal failure and improves survival. Whether albumin has similar beneficial effects in patients with infections other than SBP is unknown. METHODS: One hundred and ten patients with cirrhosis hospitalized for infections other than SBP were randomly assigned to receive antibiotics plus albumin (1.5 g/kgbw at diagnosis and 1 g/kgbw at day 3) (albumin group; n=56) or antibiotics alone (control group; n=54). The primary end point was survival at 3 months. Secondary end points were effects on renal and circulatory function. RESULTS: The renal function, as evaluated by differences in changes in serum creatinine and estimated glomerular filtration rate between the two groups, improved in patients treated with albumin. The circulatory function improved significantly in patients treated with albumin, but not in those from the control group. There was a trend for a lower frequency of type 1 hepatorenal syndrome in the albumin group compared to the control group (1 vs. 4 patients, respectively; p=n.s.). Probability of survival at 3 months was not significantly different among the two groups. However, when adjusted for factors with independent prognostic value, treatment with albumin was an independent predictive factor of survival. CONCLUSIONS: As compared with standard antibiotic therapy alone, treatment with albumin together with antibiotics has beneficial effects on the renal and circulatory function and shows a potential survival benefit. Further studies with large sample sizes should be performed to confirm these findings.