What is rpf kidney. Effective renal plasma flow (ERPF) is defined as the volume of plasma that p...

What is rpf kidney. Effective renal plasma flow (ERPF) is defined as the volume of plasma that passes through the kidneys per unit time, typically calculated using the excretion rate of para amino hippuric acid (PAH), and averages about 600 mL min−1. 5,. In this paper two approaches to computerized renal nuclear medicine are presented. Filtration Fraction as ratio of GFR to RPF Filtration Fraction (FF) is the ratio of the glomerular filtration rate (GFR) to the renal plasma flow (RPF) and helps quantify the proportion of fluid that passes into renal tubules, thus giving a measure of how well the kidneys are functioning. 5 Because RPF decreases relatively more than GFR, filtration fraction (defined as GFR/RPF) increases with RPF frequently causes renal insufficiency mainly due to urinary tract obstruction. Untreated patients may develop severe complications including progression to end-stage kidney disease [1]. 2 - 0. Jul 17, 2023 · Glomerular filtration rate (GFR) represents the flow of plasma from the glomerulus into Bowman’s space over a specified period and is the chief measure of kidney function. Feb 13, 2019 · Introduction Renal clearance describes the amount (volume) of plasma that is completely cleared by the kidneys per unit time in other words it reflects the excretion of a substance (e. Achieve rapid changes in body fluids volumes and composition through changes in renal excretion of water and solutes. One critical aspect of kidney function is delivery of renal blood and plasma flow to the kidneys. Thus, when blood pressure goes up, smooth muscle in the afferent capillaries contracts to limit any increase in blood flow and filtration rate. We aimed to systematically evaluate the evidence for such an association. It is measured in milliliters per minute (ml/min). He is responsible for establishing the RPF service at Guy's and has given numerous talks on RPF all over the world Archie Fernando is a consultant urological surgeon at Guy's and St Thomas' Hospital. Roles served by Renal Blood Flow: Sustain filtration and excretion of end products such as urea, creatinine etc. Derive an expression for estimating renal plasma flow (RPF) and, hence, renal blood flow Describe the attributes of an appropriate indicator substance, such as PAH (para-aminohippuric acid), such that mass excreted = mass delivered to the kidneys, and re-arrange the equation to give RPF; then, utilising packed cell volume (PCV), derive renal RPF is not a disease of the kidney itself but since the kidney can be involved and impaired because of obstruction of the urine getting out, a nephrologist (kidney doctor) may be involved to assist in monitoring of renal function. To facilitate clinical research, diagnosis and treatment, nephrologist Paul Scheel and his Johns Hopkins colleagues have developed the following diagnostic criteria for RPF: A soft tissue, homogenous density surrounding the infrarenal aorta or Mar 11, 2021 · Retroperitoneal fibrosis is a rare condition that occurs when excess fibrous tissue develops in the space behind your stomach and intestine, often blocking your urinary tubes and causing kidney The kidney is the most robustly perfused organ per gram of tissue in the human body, receiving 20% to 25% of cardiac output. The ideal solute for calculation is excreted completely by the kidney, such that the renal venous concentration is zero, and it is not metabolized by the kidney. This test i s reviewed by your doctor and team, including your renal dietitian. Sep 1, 2017 · Retroperitoneal fibrosis (RPF) is a condition that occurs when extensive fibrosis develops in the retroperitoneum, usually centred over the anterior aspect of the fourth and fifth lumbar vertebrae. The clearance of inulin is shown to be equal to the GFR, glomerular filtration rate. Key Areas Covered 1. The results of the survey were presented at UK Kidney Week 2017. The high blood flow and the kidney’s unique vascular anatomy play a crucial role in renal function. •Give Sep 4, 2025 · Retroperitoneal fibrosis (Ormond’s disease) occurs when scar-like tissue develops in the back of your abdomen. Sep 30, 2025 · The filtration fraction (FF) represents the portion of blood plasma that gets filtered by the glomerulus relative to the total renal plasma flow (RPF). The RPF Rare Disease Group conducted a patient focused online study to understand the un-met medical need of patients with retroperitoneal fibrosis. The major sites of resistance within the kidney are the afferent and efferent arterioles, with an approximately 80% to 90% decrease in perfusion pressure across this region of the renal vasculature (Fig. During efferent arteriole constriction, GFR is increased, but RPF is decreased, resulting in increased filtration fraction. Retroperitoneal Fibrosis (RPF) is a condition where a thick, inflamed tissue forms deep inside the abdomen, in a space called the retroperitoneum. Approximately 92% of plasma Jul 18, 2025 · The renal function panel (aka renal function tests or RFTs) is one of the blood tests your physician will order when you have kidney disease. All entries were anonymous. FF normal values range between 17 and 23%. It varies from one substance to another and it tells us the volume of blood plasma that is completely cleared of a given substance over a time period by the kidney. GFR measures the volume of fluid filtered by the glomeruli per unit of time, reflecting the kidney's ability to filter waste products from the blood. A reduced GFR might indicate issues with the filtering capacity of the kidneys, such as in chronic kidney disease. It can affect your urinary system, kidneys and more. Abstract During acute kidney injury (AKI), lowered glomerular filtration rate (GFR) is believed to be consequent to reduced renal plasma flow (RPF). 1 The fall in RPF with age is greater in men than in women and in those who are hypertensive. 2 L/min. Renal dysfunction during pregnancy is a common and serious complication. The disease process typically begins with clinical symptoms of flank pain, and unexplained weight loss. Mar 3, 2016 · Diagnosing Retroperitoneal Fibrosis Until now, ambiguity surrounding the diagnosis of RPF has hampered formal studies of the disease and its treatment. Mathematically, it is defined as the ratio of the Glomerular Filtration Rate (GFR) to the Renal Plasma Flow (RPF). 2 L/min: 660 = 1200 (100 –45/100) mL Renal blood flow and renal plasma flow The kidneys receive 25% or more of cardiac output. The concentration of PAH is measured in one arterial blood sample (P PAH) and one urine sample (U PAH). These two bean-shaped organs interact with the cardiovascular system to maintain hemodynamic stability. RPF measures the volume of plasma that flows through the kidneys per unit of time, providing an indication of blood flow to the kidneys. renal plasma flow (RPF) the amount of plasma that perfuses the kidneys per unit time, approximately 90 per cent of the total constitutes the effective renal plasma flow, the portion that perfuses functional renal tissue such as the glomeruli. In dogs, more than 90% of RBF is normally Be aware that it does not measure true renal plasma flow because some PAH remains in the blood (approximately 10%). 5 Renal Plasma Flow RPF = C / E RPF = 10 ml/min / 0. The concepts of clearance are introduced. First, the Filtration fraction (FF) is the fraction of renal plasma flow (RPF) filtered across the glomerulus [11] (calculated as GFR divided by RPF [11]). The pressure-flow relationship is fundamental to circulatory hemodynamics of any organ. Jan 1, 2007 · Glomerular filtration rate and renal plasma flow increase by 40 to 65 and 50 to 85%, respectively, during normal pregnancy in women. It varies with body surface and sex in the same way as the GFR. RPF Nephrology Abbreviation RPF in Nephrology refers to Renal Plasma Flow, a measurement that indicates the volume of plasma that passes through the kidneys per unit of time, essential for assessing kidney function and health. 2 mg/100 ml P V = 0. By filtering 20% of its blood flow, the kidney acts as a selective plasma filter and so maintains the homeostasis of extracellular fluid, despite variations in daily fluid and electrolyte intake. Effective renal plasma flow (ERPF) can be measured by infusion of p -aminohippurate (PAH). Blockade of beta-receptors may therefore be expected to influence renal blood flow and possibly glomerular filtration rate by intrarenal effects as well as by red … Aug 11, 2023 · Patients may require medical therapy for the RPF and endovascular, urological, or surgical treatment for management of complications. You will learn how each of these processes works and where they occur along the nephron and collecting ducts. Learning Objectives: •Derive an expression for estimating renal plasma flow (RPF) and, hence, renal blood flow. We would like to show you a description here but the site won’t allow us. The renal plasma flow is about 660 mL min −1. Understanding normal physiology during pregnancy provides a context to further describe changes in pregnancy that lead to renal dysfunction and may provide clues to better Jan 1, 2012 · Since the functioning of the kidneys depends on filtration of the plasma, the blood flow to the kidneys is of obvious importance. 1 liters per minute) with the blood entering individual glo … Giulio Masotti Human kidneys receive 1 l/min of blood flow—1/5 of cardiac output—which is the highest flow per gram of organ weight in the body. The RPF Rare Disease Group have recently conducted a patient focused online study to understand the un-met medical need of patients with retroperitoneal fibrosis. 1 The location of the urinary tract obstructions and the lesions causing it vary widely. RPF frequently causes renal insufficiency mainly due to urinary tract obstruction. FF is about 20% indicating that the remaining 80% continues its pathway through the renal circulation. Inputs to this equation are: In the physiology of the kidney, renal blood flow (RBF) is the volume of blood delivered to the kidneys per unit time. Renal Plasma Flow RPF is calculated by the clearance of para-aminohippuric acid (PAH), as at low concentrations this compound is completely cleared from the plasma by renal tubular filtration and secretion in a single pass. Mar 5, 2016 · The amount of blood and the amount of plasma that pass through all the glomeruli of the kidney can be quantified by the renal blood flow and renal plasma flow. Mar 31, 2023 · the unfiltered RPF will then be part of the peritubular capillary blood flow after entering the efferent arteriole Filtration fraction (FF) = GFR / RPF Filtered load = GFR x plasma concentration Renal plasma flow (RPF) can be determined by using clearance of para-aminohippuric acid (PAH) Renal Blood Flow (RBF) Definition: Renal blood flow (RBF) is the amount of blood flowing through the kidneys, essential for filtration and oxygen supply, especially to the medulla, which is vulnerable to RBF is closely related to renal plasma flow (RPF), which is the volume of blood plasma delivered to the kidneys per unit time. UK Kidney Week 2017 RPF Patient Survey Poster – James Tomlinson et al, Clinical Lecturer in Renal Medicine, Institute of Clinical Sciences, Imperial College, London Feb 24, 2026 · RBF = RPF/ (1 - Hct) Renal plasma flow (RPF): the volume of plasma that flows through the kidney per unit of time Para-aminohippuric acid (PAH): nearly 100% of PAH that enters the kidney is also excreted (completely filtrated and secreted), thus clearance rate is used to estimate RPF Effective renal plasma flow (eRPF) He has expertise in complex retroperitoneal surgery, kidney cancer and testis cancer. Jan 19, 2025 · What is Renal Plasma Clearance? Renal plasma clearance (RPF) is a measurement of how much blood plasma is filtered by the kidneys per minute. Renal blood flow (RBF) … Giulio Masotti Human kidneys receive 1 l/min of blood flow—1/5 of cardiac output—which is the highest flow per gram of organ weight in the body. It represents the amount of plasma that effectively contributes to the filtration and secretion processes occurring in the renal system. Effective Renal Plasma Flow (ERPF) (Para-aminohippuric Acid [PAH] Clearance) A measure (in ml or cc per minute) of the volume of plasma flowing through the kidney. The first approach deals with tubular function kinetics Abstract The three fundamental operations of the kidney are ultrafiltration, reabsorption, and secretion, and all three are performed in miniature by each nephron. Thus, in a patient exhibiting signs and symptoms of kidney disease, clinicians should take caution in prescribing NSAIDs. It is named after John Kelso He has expertise in complex retroperitoneal surgery, kidney cancer and testis cancer. While blood flow certainly serves these functions in the kidneys, it does much more. Renal clearance of PAH is thus useful in calculation of renal plasma flow (RPF), which empirically is (1- hematocrit) times renal blood flow. Retroperitoneal fibrosis or Ormond's disease is a disease featuring the proliferation of fibrous tissue (fibrosis) in the retroperitoneum, the compartment of the body containing the kidneys, aorta, renal tract, and various other structures. Renal plasma flow is given by the Fick principle: This is essentially a conservation of mass equation which balances the renal inputs (the renal artery) and the renal outputs (the renal vein and ureter). The Renal Blood Flow equation computes the RBF based on the plasma flow rate (RPF) and the volume (%) of red blood cell. The E of a solute is equal to the fraction of the substance that is removed from the plasma in one pass through the kidney: E = P A - P V / P A Calculate E P A = 0. The glomerular filtration rate (GFR) is thus maintained, and blood filtration can continue despite lowered overall kidney blood flow. RPF is an important measure of kidney function because it reflects the glomerular filtration rate (GFR), which Overview of Renal Plasma Flow (RPF) Renal plasma flow (RPF) refers to the amount of plasma that passes through the kidneys per unit time. In this article, we’ll cover exactly what Renal plasma flow Any solute that is completely cleared as it flows through the kidney can be used to measure the RPF using the principles of renal clearance as outlined above. Put simply, a non-metabolizable solute entering the kidney via the renal artery has two points of exit, the Renal Plasma Flow RPF is calculated by the clearance of para-aminohippuric acid (PAH), as at low concentrations this compound is completely cleared from the plasma by renal tubular filtration and secretion in a single pass. They excrete metabolic waste, regulate fluid and electrolyte balance, promote bone integrity, and more. It is normally about 20%. 1 mg/100 ml E = 0. Jan 23, 2019 · Furthermore, renal plasma flow only measures the amount of plasma that passes through the kidney while renal blood flow measures both plasma and hematocrit that pass through the kidney. RPF Retroperitoneal fibrosis (RPF) is a rare condition characterized by the presence of inflammation and fibrosis in the retroperitoneal space. - Important determinant of GFR (↑RPF → ↑filtrate formed) - Can be used to estimate renal blood flow (RBF) - Both RPF and RBF are indicators of renal health Estimate RPF An appropriate indicator substance for estimating RPF is one where: Mass excreted = mass delivered to Measurement of separate kidney function is important in the differential diagnosis of arterial hypertension and in cases where surgical reduction of renal parenchyma is considered. To express this mathematically: The clearance of PAH and effective renal plasma flow are equal to: – The urine concentration of PAH multiplied by the urine flow rate divided by the plasma concentration of PAH. The physiologic goal is to modify Find out about retroperitoneal fibrosis: symptoms, diagnosis, treatment and sources of further information and support. More than 90% of blood flow serves the cortex. Of note, the clearance of PAH is reflective only of RPF to portions of the kidney that deal with urine formation, and, thus, underestimates the actual RPF by about 10%. You will discover that different parts of the nephron utilize specific processes to produce urine: filtration, reabsorption, and secretion. 1 / 0. This can be measured by the para-aminohippuric acid (PAH) or diodrast clearance as low concentrations of these substances are cleared completely by tubular secretion each pass through the kidney. It is a vital physiological parameter that allows clinicians and researchers to assess renal perfusion. May 1, 2018 · The kidney depends on its blood flow (20–25% cardiac output) and glomerular ultrafiltration (20% renal plasma flow) to perform it's homoeostatic and excretory functions. In large part, this is due to the autoregulatory nature of smooth muscle. This parameter is crucial for understanding renal hemodynamics and can help diagnose various kidney disorders. Since only the plasma is relevant to the excretion of most substances, the term renal plasma flow (RPF) is often used, rather than renal blood flow. All Osmosis Notes are clearly laid-out and contain striking images, tables, and diagrams to help visual learners understand complex topics quickly and efficiently. 2 Renal Clearance, Renal Plasma Flow and Glomerular Filtration Rate Renal clearance is a measurement that is used to analyze and study the function of the kidneys. It is calculated by taking the amount of a substance in the urine and dividing it by the concentration of that substance in the blood plasma. The normal RPF in humans typically ranges from 600 to 700 mL per minute, highlighting its role in maintaining kidney efficiency and fluid homeostasis. The filtration fraction of GFR/RPF is typically about 0. Renal blood flow Healthy renal blood flow is normally about 1. Jul 24, 2023 · The kidneys function in a wide variety of ways necessary for health. This renal plasma flow calculator determines RPF by the clearance of para-aminohippuric acid (PAH) which is a measure of renal function. Both RPF and RBF are measured in milliliters per minute (ml/min), and both are important measures of kidney function. Selectivity of molecular filtration in the glomerulus is related to molecular size, shape and electrostatic charge of molecules, and structure of the glomerular filtration Effective Renal Plasma Flow (ERPF) is defined as the volume of plasma flowing through the kidney, measured in ml or cc per minute, and can be assessed using the clearance of para-aminohippuric acid (PAH), which is secreted almost completely by the tubular system during each pass through the kidney. 12 In addition, renal insufficiency can be caused by renal parenchymal lesions referred to as IgG4-related kidney disease (IgG4-RKD) 13, 14 especially in IgG4-related RPF. Jun 9, 2024 · What is RPF? Renal plasma flow (RPF) is the volume of blood plasma passing through the kidneys per minute. Physician Mo Atta RBF is closely related to renal plasma flow (RPF), which is the volume of blood plasma delivered to the kidneys per unit time. In contrast, a reduced RPF might hint at compromised blood flow to the kidneys, potentially due to vascular issues. The kidneys receive 20% to 25% of the cardiac output (about 1. AI generated definition Quantitation of renal function has been performed for many years. g. It is the amount of plasma that perfuses the kidneys per unit time. If the haematocrit is 45%, the RPF is 660 mL/min when the blood flow is 1. Understand the mechanisms involved in tubular reabsorption and secretion, contributing to urine formation and kidney function. In the kidney, renal perfusion pressure (RPP), defined as the gradient between mean arterial pressure and renal venous pressure or mean systemic filling The E of a solute is equal to the fraction of the substance that is removed from the plasma in one pass through the kidney: E = P A - P V / P A Calculate E P A = 0. RENAL BLOOD FLOW AND RENAL PLASMA FLOW The kidneys receive 25% or more of cardiac output. The filtration fraction, therefore, represents the proportion of the fluid reaching the kidneys that passes into the renal tubules. Blood flow is not uniform throughout the kidney. Because the filtration fraction, which is the ratio of the glomerular filtration rate (GFR) to the renal plasma flow (RPF), has increased, there is less plasma fluid in the downstream peritubular capillaries. Find more information about Renal Blood Flow Regulation The kidney is able to cope with a wide range of blood pressures. Renal plasma flow (RPF) and renal blood flow (RBF) are two measurements applied for the arterial blood delivered to the kidney. 0 to 1. GFR on its own is the most common and important measure of Oct 21, 2021 · Glomerular filtration rate (GFR) and renal plasma flow (RPF) are measurements used to assess kidney function. Another useful area of the investigation of renal blood flow is the evaluation of renal transplant. Autoregulation of RBF is Renal Clearance: Analysis of Kidney Function, GFR, RPF and the Filtered Load Pete Meighan 6. Kidney plasma flow (RPF) is defined as the volume of plasma that passes through the kidneys per unit time, typically measured at approximately 650 ml/min, and can be calculated using the clearance of p-Aminohippurate (PAH). When the FF increases, the protein concentration of the peritubular capillaries increases [11]. 5 RPF = 20 ml / min Renal Blood Flow RBF = RPF x 1 / 1- hct If hct = 0. Therefore, RPF is an important measure of the kidney function. The major sites of resistance within the kidneys are the afferent and efferent arterioles, with an approximately 80% to 90% decrease in perfusion pressure across this region of the renal vasculature (Fig. The filtration fraction equation is: [1] . Effective Renal Plasma Flow (ERPF) is defined as the volume of plasma flowing through the kidney, measured in ml or cc per minute, and can be assessed using the clearance of para-aminohippuric acid (PAH), which is secreted almost completely by the tubular system during each pass through the kidney. Various methods have been developed and the introduc tion of computers to nuclear medicine has resulted in nuclear medicine studies of the kidney becoming a very powerful diagnostic tool. Your labs can provide your healthcare providers with details of what is going on inside your body- whether you realize it or not. This area includes important organs like the kidneys, ureters (the tubes that carry urine from the kidneys to the bladder) and major blood vessels. 2). FF is a measure of the kidney function, and although it is typically not used in routine clinical practice, it can be a helpful measure to understand how the kidneys respond under certain Oct 29, 2023 · When assessing kidney health, both glomerular filtration rate and renal plasma flow provide different perspectives. 65. Renal plasma flow (RPF) is the volume of blood plasma passing through the kidneys per minute; whereas renal blood flow (RBF) is the volume of blood flowing through the renal arteries per minute. Jul 1, 2021 · Renal plasma flow Any solute that is completely cleared as it flows through the kidney can be used to measure the RPF using the principles of renal clearance as outlined above. It is named after John Kelso RBF is closely related to renal plasma flow (RPF), which is the volume of blood plasma delivered to the kidneys per unit time. Feb 24, 2026 · RBF = RPF/ (1 - Hct) Renal plasma flow (RPF): the volume of plasma that flows through the kidney per unit of time Para-aminohippuric acid (PAH): nearly 100% of PAH that enters the kidney is also excreted (completely filtrated and secreted), thus clearance rate is used to estimate RPF Effective renal plasma flow (eRPF) Derive an expression for estimating renal plasma flow (RPF) and, hence, renal blood flow. 2-6). RBF is inversely proportional to the resistance of the renal vasculature. 2 E = 0. , medications) this depends on glomerular filtration Having reviewed the anatomy and microanatomy of the urinary system, now is the time to focus on the physiology. Retroperitoneal fibrosis (RPF) is a rare condition characterized by the presence of inflammation and fibrosis in the retroperitoneal space. When you stretch it, it contracts. High value of RPF indicates good kidney function while low values indicate poor kidney function. Renal blood flow (RBF) … The filtration fraction in kidney function refers to the proportion of the blood that passes through the kidneys that is actually filtered through the glomerulus. It may present with lower back pain, kidney failure, hypertension, deep vein thrombosis, and other obstructive symptoms. Describe the attributes of an appropriate indicator substance, such as PAH (para-aminohippuric acid), such that mass excreted = mass delivered to the kidneys, and re-arrange the equation to give RPF; then, utilising packed cell volume (PCV), derive renal blood flow (RBF). While the terms generally apply to arterial blood delivered to the kidneys, both RBF and RPF can be used to quantify the volume of venous blood exiting the kidneys per unit time. Inflammation and fibrosis surround the aorta at the level just below your kidneys. Physician Mo Atta PAH is completely removed from blood that passes through the kidneys (PAH undergoes both glomerular filtration and tubular secretion), and therefore the rate at which the kidneys can clear PAH from the blood reflects total renal plasma flow. Renal blood flow (RBF) is directly proportional to the transrenal gradient, the pressure difference between the renal artery and renal vein, and inversely proportional to the resistance of the renal vasculature. Give an account of the functional Note that RBF can be calculated from RPF by the equation RBF = RPF/ (1 - hematocrit). All renal blood is delivered to the cortex where it flows through glomerular capillaries. 43K subscribers Subscribed Jul 22, 2023 · Explore the physiology of renal blood flow and filtration, including the factors influencing kidney perfusion and glomerular filtration rate. Renal Plasma Flow Renal plasma flow (RPF) also decreases from a mean of 650 ml/min in the fourth decade to 290 ml/min by the ninth decade, with increasing renal vascular resistance (Fig. AI generated definition based on: Comprehensive Clinical Nephrology (Fourth Edition), 2010 Renal plasma flow is the volume of plasma that reaches the kidneys per unit time. Renal Blood Flow The kidney is the most robustly perfused organ per gram of tissue in the human body, receiving 20% to 25% of cardiac output. Blood flow is not uniform throughout the kidneys. alpha-, beta 1- and beta 2-adrenergic receptors in the kidney mediate vasoconstriction, renin secretion and vasodilatation, respectively. It is a crucial parameter in the assessment of renal function. Studies using the gravid rat as a model have greatly enhanced our understanding of mechanisms underlying these remarkable changes in the renal circulation during gesta … This Osmosis High-Yield Note provides an overview of Renal Blood Flow Regulation essentials. 5, Jul 6, 2005 · • Infrequently needed in routine clinical practice • Derived from rate of clearance of a marker that is totally extracted from plasma after first pass through kidney; this yields RPF • Renal blood flow (RBF) can be obtained by dividing RPF by (1- hematocrit) • Jul 1, 2021 · Renal plasma flow Any solute that is completely cleared as it flows through the kidney can be used to measure the RPF using the principles of renal clearance as outlined above. UK Kidney Week 2017 RPF Patient Survey Poster – James Tomlinson et al, Clinical Lecturer in Renal Medicine, Institute of Clinical Sciences, Imperial College, London In renal physiology, the filtration fraction is the ratio of the glomerular filtration rate (GFR) over the renal plasma flow (RPF). How the blood flow and glomerular filtration rate (GFR) are regulated is the subject of the second part of this chapter. Renal blood flow (RBF) is directly proportional to the “trans-renal gradient,” the pressure difference between the renal artery and renal vein. High values indicate good kidney function, while low values indicate poor kidney The RPF Rare Disease Group have recently conducted a patient focused online study to understand the un-met medical need of patients with retroperitoneal fibrosis. iyjwu ubni tctgh ibcns vhtofu vjxekgdg difbapi ubvd ukpvgp ilgsd