Diuretic Resistance Treated with Low-Dose Hydralazine: A Case Report and Review of the Literature

We present a case of severe diuretic resistance and edema from acute cardiorenal syndrome complicating heart failure with preserved ejection fraction (HFpEF) and mild alcoholic liver disease. High doses of intravenous (iv) furosemide plus iv doses of chlorothiazide failed to increase the daily urine output (UV) above 1,500 mL or the fractional excretion of sodium (FE_Na) above 2%. The addition of a relatively low dose of hydralazine (10 mg thrice daily PO) during 5 days of constant iv infusion of furosemide plus iv bolus chlorothiazide doubled the UV and FE_Na while reducing the serum creatinine concentration from 3.3 to 2.0 mg/dL. Hydralazine may have restored a response to the diuretics by increasing the renal blood flow and thereby the renal diuretic delivery, or by reducing the filtration fraction or reducing the renal congestion and thereby reducing the proximal reabsorption during blockade of distal reabsorption with diuretics. Further mechanistic studies of low-dose hydralazine for diuretic resistance are warranted.

Mineral composition of bottled water in Northwestern Federal District Russian Federation

Introduction. Urolithiasis is a widespread disease with high the frequency of recurrence. An important preventive measure is an increase in daily urine output. Patients with urolithiasis need to take into account the mineral the composition of the fluid consumed, since it can affect the formation of stones. It is especially important to pay attention to the composition of bottled water purchased in retail chains due to its significant differences. Purpose. Analyze the composition of bottled water sold in retail chains of the Northwestern federal district (NWFD). Conduct a comparative analysis of the compositions carbonated and still water, as well as compare the composition of domestic and European bottled still water. Materials and methods. An independent laboratory determined the mineral composition of 36 samples of bottled water purchased in 2 retail chains of the NWFD. Done сomparison of the compositions of 19 samples of still and 16 samples of carbonated water. Comparison of the compositions of domestic and European non-carbonated bottled water. Results. The data obtained by us on the mineral composition of the purchased water samples corresponded to the indicators declared by the manufacturers. Comparison of carbonated and still water showed no statistically significant differences in the content of calcium, sodium, magnesium, potassium, sulfates, hydrocarbons. Comparison of the mineral composition of domestic still and European still bottled water showed the presence of statistically significant differences in the content of calcium and hydrocarbonates, which were higher in the water of European manufacturers. Conclusions. The mineral composition of bottled water can vary significantly. It is important for patients with urolithiasis to take into account the mineral composition of the water, which they consume, so it can influence the development of relapse.

Polyuria in a Patient With a Pituitary Mass

Background: Hypocortisolism can develop in patients with a pituitary mass because of hypopituitarism and is appropriately managed with steroid replacement. However, these patients often have co-existing endocrine derangements that can become clinically evident after administration of steroids. Clinical Case: A sixty-year-old Caucasian female with known non-small cell lung cancer on chemoimmunotherapy was admitted for management of an enlarging suprasellar mass. Her symptoms included nausea, vomiting and multiple syncopal episodes over the preceding three weeks. At the time of admission, physical examination was unremarkable. She was noted to be hypotensive with systolic blood pressure in the high 70s and was treated with intravenous fluids. Laboratory evaluation showed low random cortisol (0.99 ug/dL, n: 0.4-22.6 ug/dL), undetectable ACTH (<5 pg/mL, n: 7.2-63 pg/mL), low free thyroxine (1.01 ug/dL, n: 0.93-1.7 ug/dL), low free T3 (1.6 pg/mL, n: 2-4.4 pg/mL) and low TSH (0.023 ug/dL, n: 0.27-4.2 ug/dL), consistent with central hypothyroidism and secondary adrenal insufficiency. Importantly, she was normonatremic and normokalemic at admission. She was started on stress dose hydrocortisone (100 mg IV q8h) for presumed adrenal crisis. Following institution of steroid replacement therapy, the patient rapidly became polyuric while simultaneously developing hypernatremia. Her daily urine output peaked at 4400 mL corresponding temporally to a maximum serum sodium of 160 mmol/L. A single dose of 0.5 mg of desmopressin resulted in immediate lowering of daily urine output to 750 mL and appropriate improvement in urine osmolality from 147 mOsm/kg to 565 mOsm/kg, confirming a diagnosis of central diabetes insipidus (cDI). Conclusion: Hypocortisolism is known to impair free water excretion by stimulating arginine vasopressin (AVP) secretion through renal sodium loss and consequent volume depletion as well as direct feedback stimulation of corticotrophin releasing hormone (CRH) and AVP within the hypothalamus. Conversely steroid replacement leads to loss of feedback stimulation, unmasking cDI. This unique convergence of cDI with hypocortisolism is most often encountered in patients with hypopituitarism. Hence patients with secondary adrenal insufficiency should be carefully monitored for cDI after initiation of steroid replacement therapy.

P1097INITIATING MAINTENANCE HAEMODIALYSIS USING INCREMENTAL HAEMODIALYSIS REGIME - A SINGLE CENTRE EXPERIENCE

Background and Aims Most patients with end stage renal disease (ESRD) initiate maintenance dialysis in three times per week regime irrespectively of residual kidney function (RKF). Incremental haemodialysis (IHD) showed benefits of starting and maintaining patients on less than three times per week regime, most importantly preserving urine volume output (UVO) and RKF. The aim of this study was to assess the main differences between a group of patients initiating dialysis once-weekly (1xHD) and twice-weekly (2xHD), to evaluate time to dialysis regime change, UVO and patients volume status at the end of study period. Method Patients with ESRD who started haemodialysis through the planned IHD (once-weekly and twice-weekly) and were undergoing IHD for at least 4 months (M) were enrolled (n=44) in the study. Study was conducted from January 2016 to December 2019 at dialysis department of our hospital. Patients were divided into two groups: 1xHD (20 pts) and 2xHD (24 pts). They were excluded from the study at the end of study period or earlier if they transitioned to thrice-weekly haemodialysis or died. Patients fluid status and body composition was assessed using results derived from bioimpedance measurements performed using Body Composition Monitor device. Results The 1xHD pts were younger (66,8±11,6 versus 67,4±10 years: P>0.05) and weighed less (74,4±14,7 versus 75,5±11,9 kg, p>0,05) with lower BMI. In both groups there were more males (60% versus 62,5%: P>0,05). The most common cause of ESRD in both groups was nephrosclerosis (45% in 1xHD versus 47,1% in 2xHD, p>0,05), followed by diabetic nephropathy (30% versus 20,8%, p>0,05), obstructive nephropathy (10% versus 8,3%, p>0,05), multiple myeloma (10% versus 8,3%, p>0,05), glomerulonephritis (5% versus 8,3%, p>0,05) and others in 2xHD group (12,5%; polycystic kidney disease and chronic interstitial nephritis). The estimated glomerular filtration rate of all patients at the time of HD initiation was 7,5±2,2 ml/min/1.73m2 (8,2±2,8 in 1xHD group versus 6,9±1,48 ml/ min/1.73m2 in 2xHD group, p>0,05). Baseline daily urine output was similar, 1826,6±344,6 ml/day in 1xHD and 1772,2±343,8 ml/day in 2xHD group (p>0,05). Patients in 1xHD concluded the study after mean period of 13,4 M (min 4 M, max 35 M). At the end of study period only three patients (15%) continued receiving dialysis once-weekly (mean 14,5 M, min 7 M, max 19 M), 12 pts (60%) transitioned to twice-weekly dialysis regime after 2 to 6 M (mean 3,1 M) and continued to receive this dialysis regime until the end of study period. Four pts (20%) transitioned to full-dose dialysis (mean 18,2 M, 11-24 M). Most of the patients in 2xHD group (17; 70,8%) concluded study in the same dialysis regime (mean 20,4 M, 4-24 M), 7 pts (29%) transitioned to full-dose dialysis (mean 12,6 M, 5-21 M) and one patient transitioned to once-weekly HD (8M). At the end of study daily urine output was 1463,1±317,5 in 1xHD versus 1321,1±309,1 ml/day in 2xHD group (p>0,05). Results of assessment of fluid status and body composition at the end of study are in Table 1. We evaluated nutritional status at the end of study: total protein 57,4±8,9 g/l in 1xHD versus 62,8±5,3 g/l in 2xHD, albumin 36,9±10,6 versus 37,6±4,4 g/l, total cholesterol 4,1±1,6 versus 4,4±1,3 mmol/l, triglycerides 1,3±0,8 versus 1,7±0,7 mmol/l (p>0,05 for all parameters). At the end of the study 70% of patients treated with IHD maintained renal function that was sufficient to continue IHD regime with overall survival rate 90% in 1xHD group and 87,5% in 2xHD group. Conclusion IHD, in carefully selected patients with good compliance, provides preservation of UVO and RKF, thus delaying transition to full-dose dialysis and avoiding complications of dialysis, such as intradialytic hypotension and vascular access failure. This type of dialysis is individualized treatment that obtains easier adaptation to dialysis and better quality of life.

The urea transporter UT-A1 plays a predominant role in a urea-dependent urine-concentrating mechanism

Urea transporters are a family of urea-selective channel proteins expressed in multiple tissues that play an important role in the urine-concentrating mechanism of the mammalian kidney. Previous studies have shown that knockout of urea transporter (UT)-B, UT-A1/A3, or all UTs leads to urea-selective diuresis, indicating that urea transporters have important roles in urine concentration. Here, we sought to determine the role of UT-A1 in the urine-concentrating mechanism in a newly developed UT-A1–knockout mouse model. Phenotypically, daily urine output in UT-A1–knockout mice was nearly 3-fold that of WT mice and 82% of all-UT–knockout mice, and the UT-A1–knockout mice had significantly lower urine osmolality than WT mice. After 24-h water restriction, acute urea loading, or high-protein (40%) intake, UT-A1–knockout mice were unable to increase urine-concentrating ability. Compared with all-UT–knockout mice, the UT-A1–knockout mice exhibited similarly elevated daily urine output and decreased urine osmolality, indicating impaired urea-selective urine concentration. Our experimental findings reveal that UT-A1 has a predominant role in urea-dependent urine-concentrating mechanisms, suggesting that UT-A1 represents a promising diuretic target.

Predictive factor for successful retrograde ureteral stent insertion in obstructive uropathy due to advanced cervical cancer

Cervical cancer is the 3rd most common cancer in women. Some of the patients came with kidney failure due to malignant ureteral obstruction. Retrograde ureteral stent insertion as palliative urinary diversion often performed on these patients, but it has high failure rate and often has to be converted to nephrostomy, giving the patient unnecessary burden due to failed procedure. In this study, we evaluate factors that may predict successful ureteral stenting in cervical cancer patients to avoid unnecessary burden to the patient. Data were collected from 2014-2017. We evaluate the clinical, ultrasound and laboratory findings before stent insertion of the patient with successful compared to failed insertion. Comparative study was done using independent T-test and Mann-Whitney U test for nonparametric data. Odds ratio (OR) were calculated using contingency table and P value calculated using Fisher exact test. There were 41 patients diagnosed with cervical cancer performed retrograde ureteral stenting. From 41 patients, 20 (48.7%) were successful and 21 (51.3%) failed. Low hydronephrosis grade (OR=85.8; P<0.0001), low stage (OR=6.0; P=0.0098), radiotherapy (OR=3.7; P=0.04) were strong predictor for successful stent insertion. In bilateral hydronephrosis, more daily urine output (OR=29.2; P=0.002) and normal creatinine level (OR=6.3; P=0.03) were strong predictors for successful retrograde stenting, while bladder infiltration was strong predictor for stent failure (OR=0.0684; P=0.0021). Low hydronephrosis grade, no bladder infiltration, normal creatinine level, more daily urine output, low clinical staging and radiotherapy are predictive factors to predict a successful ureteral stenting in cervical cancer patients.

DOSE-DEPENDENDENT HISTOCHROME EFFECTS OF KIDNEY IN RATS

THE AIM.Histochrome is a native antioxidant drug isolated from natural sourse. The study of pharmacological activity of histochrome showed a wide spectrum of dose-range action. The aim of this study was to investigate the renal effects changes when administered various doses of histochrome in rats.MATERIALS AND METHODS.The study was conducted on outbred stock Wistar rats. The test group of animals (n = 15) was administered subcutaneously histochrome at a dose of 1 mg/kg for 10 days, and the control group (n = 20) was treatment of 10 mg/kg of the drug. Since 3-d day every two days of experiment were measured daily urine output, excretion of Na+ and K+, creatinine excretion, and excretion of histochrome.RESULTS.The tendency of daily urination increase recorded at histochrome administration at a dose of 1 mg/kg. In the comparison group increased diuresis led to a fivefold magnification of parameter on the 7th day. Dynamic renal creatinine excretion during treatment with 1 mg / kg histochrome had a stable character throughout the experiment, while the ten-fold increase in dose was associated with a significant elevation of the factor. Natriuresis steadily increased, exceeding the initial value 5 times in under-test group of animals. In the comparison group the ion excretion increased by 2 times. Potassium excretion have similar dynamics using both histochrome doses. The native form histochrome was not detected in the urine in any of the animal groups.CONCLUSION.The experimental results showed that the behavior of the excretory renal function is histochrome dosedependent and may be due to its metabolites.