Hepatorenal syndrome

Hepatorenal syndrome (HRS) is a "functional" and reversible form of renal failure that occurs in patients with advanced chronic liver disease. The distinctive hallmark feature of HRS is the intense renal vasoconstriction caused by interactions between systemic and portal hemodynamics. This results in activation of vasoconstrictors and suppression of vasodilators in the renal circulation. Epidemiology, pathophysiology, as well as current and emerging therapies of HRS are discussed in this review.

Relationship of MTHFR gene polymorphisms with renal and cardiac disease

AIM: To investigate the effects of different methylenetetrahydrofolate reductase(MTHFR) 677C>T gene polymorphism and hyperhomocysteinemia for the development of renal failure and cardiovascular events, which are controversial.METHODS: We challenged the relationship, if any, of MTHFR 677C>T and MTHFR 1298A>C polymorphisms with renal and heart function. The present article is a reappraisal of these concepts, investigating within a larger population, and including a subgroup of dialysis patients, if the two most common MTHFR polymorphisms, C677 T and A1298 C, as homozygous, heterozygous or with a compound heterozygous state, show different association with chronic renal failure requiring hemodialysis. MTHFR polymorphism could be a favorable evolutionary factor, i.e., a protective factor for many ominous conditions, like cancer and renal failure. A similar finding was reported in fatty liver disease in which it is suggested that MTHFR polymorphisms could have maintained and maintain their persistence by an heterozygosis advantage mechanism. We studied a total of 630 Italian Caucasian subject aged 54.60 ± 16.35 years, addressing to the increased hazard of hemodialysis, if any, according to the studied MTHFR genetic polymorphisms. RESULTS: A favorable association with normal renal function of MTHFR polymorphisms, and notably of MTHFR C677 T is present independently of the negative effects of left ventricular hypertrophy, increased IntraRenal arterial Resistance and hyperparathyroidism. CONCLUSION: MTHFR gene polymorphisms could have a protective role on renal function as suggested by their lower frequency among our dialysis patients in end-stage renal failure; differently, the association with left ventricular hypertrophy and reduced left ventricular relaxation suggest some type of indirect, or concurrent mechanism.

Early renal failure as a cardiovascular disease:Focus on lipoprotein(a) and prothrombotic state

Patients with renal failure are at increased risk of cardiovascular events even at the earliest stages of disease. In addition to many classic cardiovascular risk factors, many conditions that are commonly identified as emerging risk factors might contribute to occurrence of cardiovascular disease. Changes in circulating levels of many of these emerging risk factors have been demonstrated in patients with early stages of renal failure caused by different types of renal disease and have been associated with detection of cardiovascular complications. However, for most of these factors evidence of benefts of correction on cardiovascular outcome is missing. In this article, we comment on the role of lipoprotein（a） and prothrombotic factors as potential contributors to cardiovascular events in patients with early renal failure.

Hypertensive disorders in pregnancy

Renal injury or failure may occur in the context of pre-gnancy requiring special considerations with regard to fetal and maternal health. The condition of pregnancy itself may be a major factor in such injuries. In addition,for many young women previously known to be healthy, pregnancy may be the frst presentation for routine urine and blood testing which may yield previously subclinical renal disease. As such, pregnancy may add complexity to considerations in the management of renal disease presenting coincidentally requiring knowledge of the physiologic changes and potential renal disorders that may be encountered during pregnancy.

Functional coupling of V-ATPase and CLC-5

Dent’s disease is an X-linked renal tubulopathy characterized by low molecular weight proteinuria, hypercalciuria and progressive renal failure. Disease aetiology is associated with mutations in the CLCN5 gene coding for the electrogenic 2Cl-/H＋ antiporter chloride channel 5 （CLC-5）, which is expressed in the apical endosomes of renal proximal tubules with the vacuolar type H＋-ATPase （V-ATPase）. Initially identified as a member of the CLC family of Cl- channels, CLC-5 was presumed to provide Cl shunt into the endosomal lumen to dissipate H＋ accumulation by V-ATPase, thereby facilitating efficient endosomal acidification. However, recent findings showing that CLC-5 is in fact not a Cl- channel but a 2Cl-/H＋ antiporter challenged this classical shunt model, leading to a renewed and intense debate on its physiological roles. Cl- accumulation via CLC-5 is predicted to play a critical role in endocytosis, as illustrated in mice carrying an artifcial Cl- channel mutation E211A that developed defective endocytosis but normal endo-somal acidification. Conversely, a recent functional analysis of a newly identifed disease-causing Cl- channel mutation E211Q in a patient with typical Dent’s disease confrmed the functional coupling between V-ATPase and CLC-5 in endosomal acidifcation, lending support to the classical shunt model. In this editorial, we will address the current recognition of the physiological role of CLC-5 with a specific focus on the functional coupling of V-ATPase and CLC-5.

Role of imaging in the evaluation of renal dysfunction in heart failure patients

Heart failure and kidney disease share common pathophysiological pathways which can lead to mutual dysfunction,known as cardiorenal syndrome.In heart failure patients,renal impairment is related to hemodynamic and nonhemodynamic factors.Both decreased renal blood flow and renal venous congestion due to heart failure could lead to impaired renal function.Kidney disease and worsening renal function are independently associated with poor prognosis in heart failure patients,both in acute and chronic clinical settings.The aim of this review is to assess the role of renal imaging modalities in the evaluation and management of heart failure patients.Renal imaging techniques could complete laboratory data,as estimated glomerular filtration rate,exploring different pathophysiological factors involved in kidney disease and adding valuable information about renal structure and function.In particular,Doppler examination of arterial and venous hemodynamics is a feasible and non invasive technique,which has proven to be a reliable method for prognostic stratification in patients with cardiorenal syndrome.The renal resistance index,a measure related to renal hemodynamics,can be calculated from the Doppler evaluation of arterial flow.Moreover,the analysis of Doppler venous flow patterns can integrate information from the arterial study and evaluate renal congestion.Other imaging modalities are promising,but still confined to research purposes.

Primary focal and segmental glomerulosclerosis and soluble factor urokinase-type plasminogen activator receptor

Primary focal and segmental glomerulosclerosis(FSGS) may be due to genetic or acquired etiologies and is a common cause of nephrotic syndrome with high morbidity that often leads to end-stage renal failure. The different available therapeutic approaches are unsuccessful, in part due to partially deciphered heterogeneous and complex pathophysiological mechanisms. Moreover, the term FSGS, even in its primary form, comprises a histological description shared by a number of different causes with completely different molecular pathways of disease. This review focuses on the latest developments regarding the pathophysiology of primary acquired FSGS caused by soluble factor urokinase type plasminogen activator receptor, a circulating permeability factor involved in proteinuria and edema formation, and describes recent advances with potential success in therapy.

Erectile dysfunction in hemodialysis: A systematic review

Men with chronic renal failure （CRF） on hemodialysis have been frequently associated with erectile dysfunc-tion （ED）, with an of between 20% to 87.7%. As a result of the multi-system disease processes present in many uremic men, it is apparent that the pathogenesis of ED is most probably multifactorial. Factors to be con-sidered include peripheral vascular disease, neurogenic abnormalities, hormonal disturbances and medications used for treatment of conditions associated with CRF. These physiological abnormalities may be supplement-ed by signifcant psychological stresses and abnormali-ties resulting from chronic illness. Treatment must start with the determination and treatment of the underlying causes. In addition to psychological treatment, furtherlines of treatment of ED in CRF can be classifed as 1stline （medical treatment which includes oral phosphodi-esterase-5 inhibitors and hormone regulation）, 2nd line（intracavernosal injection, vacuum constriction devicesand alprostadil urethral suppositories） or 3rd line （sur-gical treatment）. Renal transplantation improves thequality of life for some patients with CRF and subse-quently it may improve erectile function in a signifcantnumber of them, however still there is high incidenceof ED after transplantation.

Contrast induced nephropathy after percutaneous coronary intervention： risk factors and preventive strategy

Objective To analyze the risk factors and clinical outcome of contrast induced nephropathy （CIN） in patients with coronary artery disease （CAD） after percutaneous coronary intervention （PCI） and discuss its prevention. Methods Fifty-four patients with C1N among 729 patients who received PCI were retrospectively studied and the related risk factors, cardiovascular events and preventive strategy were analyzed. Results C1N was strongly associated with pre-procedure chronic renal failure, diabetes mellitus and large-dose contrast. The incidence of cardiac mortality and major adverse cardiac events 1 year after PCI in CIN group was higher than that in group without CIN. Conclusion Chronic renal failure, diabetes mellitus and dosage of contrast agent were three independent risk factors of CIN. CIN could affect the patients＇ prognosis. A well overall perioperative management of CAD patients following PCI, especially hydration therapy, is the most important strategy for prevention of CIN.

In Vitro Study on Virulence Potentials of Burkholderia pseudomallei Isolated from Immunocompromised Patients

Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cultured first in the selective media Ashdown＇s broth then subcultured on Ashdown＇s agar to isolate Burkholderia pseudomallei which was recovered from seven cases （8.33%）. Four isolates were from renal failure patients （23.53%）, two from diabetic patients （11.76%） and the seventh isolate was from an outpatient with tonsillitis. All isolates were able to produce capsules, form filament chains, exhibit swarming motility and were arabinose non assimilators （Ara-） indicative of their virulence. Additionally, isolated B. pseudomallei were found to produce protease, lipase, hemolysin, and lecithinase and were able to produce biofilm, the root of many troublesome persistent infections that resist antibiotic treatment. Susceptibility of the seven isolates of B. pseudomallei toward 11 antibiotics was assessed, isolates were found multiply resistant to all antibiotics apart from ciproflaxin. This study confirms for the first time isolation of B. pseudomallei from immunocompromised patients in Basrah city of Iraq and describes their virulence potentials.

Extra-pulmonary tuberculosis infection in the dialysis patients with end stage renal diseases:case reports and literature review

The diagnosis of extra-pulmonary tuberculosis(TB) seems relatively difficult due to the absence of specific symptoms and signs in patients on peritoneal dialysis or hemodialysis.We report four cases of extra-pulmonary tuberculosis on dialysis,with two cases on peritoneal dialysis and two cases on hemodialysis.The presentations,therapy,and outcomes of TB infection in these patients were reviewed.Otherwise,the English literature published in the PubMed database associating extra-pulmonary tuberculosis on dialysis over the last three decades is reviewed.A total of 61 studies containing 70 cases were included.The most common primary disease was diabetic nephropathy(22.86%,16/70).The peritoneum(31.42%,22/70),bone(21.42%,15/70),and lymph node(20%,14/70) were the most frequently infected.Single organ infection was common(90%,63/70).Fever(58.57%,41/70),pain(35.71%,25/70),and enlarged lymph node(20%,14/70) were the most common symptoms.Biopsy(67.14%,47/70) and culture(40%,28/70) provided most reliable methods for clear diagnosis of tuberculosis.The combined treatment of isoniazid,rifampicin,pyrazinamide,and ethambutol(44.29%,31/70) was the most common therapy.The majority of patients improved(82.86%,58/70);however,12 cases got worse(17.14%),with 10 of them dying(14.29%).Physicians should be aware of the non-specific symptoms and location of infection,and consider tuberculosis in their differential diagnoses in dialysis patients presenting with symptoms such as fever,pain,and weight loss.