{"id":7715,"date":"2021-10-24T11:32:21","date_gmt":"2021-10-24T09:32:21","guid":{"rendered":"https:\/\/meddists.com\/learn\/clinical\/hematology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/"},"modified":"2022-01-08T12:09:05","modified_gmt":"2022-01-08T10:09:05","slug":"examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy","status":"publish","type":"page","link":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/","title":{"rendered":"Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy)"},"content":{"rendered":"<span class=\"block-heading\" id=\"header_1\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">Clearance &amp; eGFR<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_1\">\n\n<\/span><span class=\"block-heading\" id=\"header_2\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Clearance<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_2\">\n\n\n<p class=\"wp-block-paragraph\">Clearance is the virtual volume of plasma cleared from a substance per unit of time.<\/p>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\"><strong>C = V*U\/P<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>C = clearance of the substance<\/li><li>V = urinary flow rate<\/li><li>U = urinary concentration of the substance<\/li><li>P = plasma concentration of the substance<\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_3\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Glomerular filtration rate (GFR) and effective glomerular filtration rate (eGFR)<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_3\">\n\n\n<p class=\"wp-block-paragraph\">GFR is the volume of plasma fluid that enters into the Bowman\u2019s capsule, per unit of time.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>It is determined by a sum of the <strong>hydrostatic <\/strong>and <strong>oncotic pressure<\/strong> <strong>gradients <\/strong>between the glomerular tuft (within the capillary) and the Bowman\u2019s capsule.<\/li><li>It is an excellent measurement of kidney function.<\/li><li>Renal diseases usually decrease GFR.<\/li><li>There are many factors that can influence GFR such as <strong>gender, age, kidney size, pregnancy, etc.<\/strong><\/li><li>An average value for GFR is 120-130ml\/min\/1.73m^2 depending on the gender.<\/li><li>It\u2019s impossible to measure GFR values directly, therefore we must rely on estimated values gathered through clearance or calculations.<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">We can estimate the GFR by measuring the clearance of substances that have <strong>little to no absorption or secretion<\/strong> in the urinary system (therefore, the clearance of the substance should be similar to the GFR). There are both endogenous and exogenous substances that may fit into this criteria, two out of which are considered the \u201cgolden standard\u201d:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>Inulin<\/strong>&nbsp;(exogenous,&nbsp;not used&nbsp;in clinical practice)<\/li><li><strong>Creatinine<\/strong>&nbsp;(endogenous, a metabolite of muscle catabolism,&nbsp;used&nbsp;in clinical practice)<\/li><li><strong>Cystatin C<\/strong> (endogenous, protease inhibitor, a newly proposed substance not yet in wide use)<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">eGFR = A calculation that relies on <strong>plasma substance <\/strong>levels,&nbsp;taking into account <strong>gender, age, height, <\/strong>and other parameters. There are various formulas and calculators available for doctors and patients to use.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Nowadays, we use Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation, and MDRD equation. CKD-EPI is more accurate, especially with higher eGFR.<\/li><li>Older methods include Cockroft-Gault equation.<\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_4\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">Proteinuria and albuminuria<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_4\">\n\n\n<p class=\"wp-block-paragraph\">Proteinuria is the excessive excretion of protein in the urine (<strong>over 150mg per 24hr<\/strong>). This can be normal (such as in <strong>functional proteinuria<\/strong>) or abnormal. <\/p>\n\n\n<\/span><span class=\"block-heading\" id=\"header_5\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Types and etiology<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_5\">\n\n\n<ul class=\"has-black-color has-text-color wp-block-list\"><li><strong>Functional proteinuria<\/strong>. A benign condition caused by an increase in protein turnover (such as pregnancy or exercise).<\/li><li><strong>Overflow proteinuria<\/strong>. Overproduction of proteins that end up in the urine.<ul><li>Multiple myeloma<\/li><\/ul><\/li><li><strong>Glomerular proteinuria<\/strong>. Leakage of proteins across the glomerulus due to impairment of the GBM.<ul><li>Glomerulonephritis<\/li><li>Chronic kidney disease<\/li><\/ul><\/li><li><strong>Tubular proteinuria<\/strong>. Faulty reabsorption of proteins in the tubular system.<ul><li>Tubulo-interstitial nephritis<\/li><\/ul><\/li><li><strong>Post-renal proteinuria.<\/strong> Due to lower urinary tract infections and tumors.<\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_6\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Diagnosis<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_6\">\n\n\n<ul class=\"wp-block-list\"><li><strong>Dip-stick<\/strong>. Can mostly detect <strong>albumin<\/strong>. Not sensitive enough to detect small amounts of protein (microalubimuria).<\/li><li>Measuring the <strong>ratio of urinary albumin to creatinine <\/strong>(ACR) from urine a sample (less than <strong>0.2<\/strong> is normal).<\/li><li>24-hour urine collection.<\/li><li>Other examinations that can be performed:<ul><li><strong>Electrophoresis<\/strong><\/li><li><strong>Microscopic examination<\/strong><\/li><li><strong>Kidney biopsy<\/strong> to evaluate kidney disease and loss of function<\/li><\/ul><\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_7\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Albuminuria<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_7\">\n\n\n<p class=\"wp-block-paragraph\"><strong>Albuminuria<\/strong> (the presence of <strong>&gt;30mg per 24hr of albumin<\/strong> in the urine) is often used interchangeably with proteinuria, although they are not the same. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Microalbuminuria <\/strong>and <strong>macroalbuminuria <\/strong>were used in the past to describe albuminuria at low (&lt;300mg\/day) and high (&gt;300mg\/day) ranges, respectively.<\/p>\n\n\n<\/span><span class=\"block-heading\" id=\"header_8\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">Hematuria<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_8\">\n\n\n<p class=\"wp-block-paragraph\">Passing of blood through the urine. It can be either <strong>macrohematuria<\/strong> where the bleeding changes the color of the urine or <strong>microhematuria<\/strong> which cannot be detected without examining it.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>The bleeding can arise from the kidney (<strong>renal<\/strong>) or the lower urinary tract (<strong>extrarenal<\/strong>).<\/li><li>In general, extrarenal bleedings are more common, and they tend to cause macrohematuria.<\/li><li>Dx using dipstick, microscopy and culture, and imaging if required.<\/li><li>DDx can be <strong>rhabdomyolysis<\/strong>, <strong>porphyria<\/strong>, and certain foods and drugs, which all may mimic macrohematuria.<\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_9\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Renal causes<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_9\">\n\n\n<p class=\"wp-block-paragraph\">Renal hematuria is classified into <strong>glomerular <\/strong>and <strong>extraglomerular<\/strong> hematuria.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>Glomerular hematuria<\/strong> is caused by inflammation or a defect of the GMB, allowing the passage of RBCs into the filtrate.<ul><li>Glomerulonephritis<\/li><li>IgA nephropathy<\/li><li>Thin GMB disease<\/li><li>Alport&#8217;s syndrome<\/li><\/ul><\/li><li><strong>Extraglomerular hematuria<\/strong> includes anything else that might go wrong with the kidney and cause bleeding.<ul><li>Nephrolithiasis<\/li><li>Pyelonephritis<\/li><li>Tumors<\/li><\/ul><ul><li>Polycystic kidney disease<\/li><li>Renal papillary necrosis<\/li><li>Sickle-cell disease<\/li><li>Trauma<\/li><\/ul><\/li><\/ul>\n\n\n<\/span><span class=\"block-heading\" id=\"header_10\">\n<h4 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title2\">Extrarenal causes<\/h4>\n<\/span><span class=\"block-content\" id=\"contents_10\">\n\n\n<p class=\"wp-block-paragraph\">Any trauma, tumor, calculus, or inflammation in the ureters, urinary bladder, prostate, or urethra may cause hematuria.<\/p>\n\n\n<\/span><span class=\"block-heading\" id=\"header_11\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">Imaging<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_11\">\n\n\n<ol class=\"wp-block-list\"><li><strong>Ultrasound<\/strong>. The kidneys are hypoechoic. Can visualize and measure kidney size, anatomy, cysts, and vasculature (Doppler).<\/li><li><strong>X-ray<\/strong>. Visualize anatomy and calcium calculi.<\/li><li><strong>I<strong>ntravenous urography<\/strong><\/strong>. Injection of an IV contrast material and X-ray.<\/li><li><strong>Retrograde (catheter) <\/strong>and <strong>anterograde (percutaneous) pyelography<\/strong>. Injection of a contrast material into the renal pelvis.<\/li><li><strong>CT<\/strong>. Can visualize calculi with high sensitivity, tumors, can be contrast-enhanced or CT-angio.<\/li><li><strong>MRI<\/strong><\/li><li><strong>SPECT\/PET<\/strong> can visualize tumors and evaluate kidney function.<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Contrast-induced nephropathy<\/strong>. Contrast material can induce <strong>AKI<\/strong>, usually 2-3 days after administration. Rare in normally-functioning kidneys. Associated with underlying diseases such as diabetes, CVD, old age, and renal impairment, especially under dehydration and metformin usage.<\/p>\n\n\n<\/span><span class=\"block-heading\" id=\"header_12\">\n<h3 class=\"wp-block-heading\" class=\"wp-block-heading\" class=\"title_collection title1\">Renal biopsy<\/h3>\n<\/span><span class=\"block-content\" id=\"contents_12\">\n\n\n<p class=\"wp-block-paragraph\">Done under mild sedation (benzos). Using ultrasound, we insert a needle percutaneously through the flank region.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Indications include:<\/p>\n\n\n\n<ol class=\"wp-block-list\" type=\"1\"><li>Unexplained nephritic\/nephrotic syndrome<\/li><li>AKI<\/li><li>Assess response to treatment<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Contraindications: Bleeding diathesis, uncontrolled HTN<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Complications: Bleeding, infection<\/p>\n<\/span><div id=\"the_titles\" style=\"display:none;\"><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">Clearance &amp; eGFR<\/h3><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Clearance<\/h4><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Glomerular filtration rate (GFR) and effective glomerular filtration rate (eGFR)<\/h4><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">Proteinuria and albuminuria<\/h3><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Types and etiology<\/h4><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Diagnosis<\/h4><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Albuminuria<\/h4><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">Hematuria<\/h3><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Renal causes<\/h4><h4 class=\"wp-block-heading\" class=\"wp-block-heading\">Extrarenal causes<\/h4><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">Imaging<\/h3><h3 class=\"wp-block-heading\" class=\"wp-block-heading\">Renal biopsy<\/h3><\/div>","protected":false},"excerpt":{"rendered":"<p>Clearance &amp; eGFR Clearance Clearance is the virtual volume of plasma cleared from a substance per unit of time. C = V*U\/P C = clearance of the substance V = urinary flow rate U = urinary concentration of the substance P = plasma concentration of the substance Glomerular filtration rate (GFR) and effective glomerular filtration [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":685,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-7715","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy) &#8211; Meddists<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"4 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/nephrology\\\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\\\/\",\"url\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/nephrology\\\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\\\/\",\"name\":\"Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy) &#8211; Meddists\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/#website\"},\"datePublished\":\"2021-10-24T09:32:21+00:00\",\"dateModified\":\"2022-01-08T10:09:05+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/nephrology\\\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/nephrology\\\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/nephrology\\\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"http:\\\/\\\/meddists.com\\\/learn\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Clinical\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Internal medicine\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/\"},{\"@type\":\"ListItem\",\"position\":4,\"name\":\"Nephrology\",\"item\":\"https:\\\/\\\/meddists.com\\\/learn\\\/clinical\\\/internal-medicine\\\/nephrology\\\/\"},{\"@type\":\"ListItem\",\"position\":5,\"name\":\"Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy)\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/meddists.com\\\/learn\\\/#website\",\"url\":\"https:\\\/\\\/meddists.com\\\/learn\\\/\",\"name\":\"Meddists\",\"description\":\"Let&#039;s Get Studying\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/meddists.com\\\/learn\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy) &#8211; Meddists","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/","twitter_misc":{"Est. reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/","url":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/","name":"Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy) &#8211; Meddists","isPartOf":{"@id":"https:\/\/meddists.com\/learn\/#website"},"datePublished":"2021-10-24T09:32:21+00:00","dateModified":"2022-01-08T10:09:05+00:00","breadcrumb":{"@id":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/examinations-in-renal-diseases-egfr-proteinuria-haematuria-imaging-renal-biopsy\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"http:\/\/meddists.com\/learn\/"},{"@type":"ListItem","position":2,"name":"Clinical","item":"https:\/\/meddists.com\/learn\/clinical\/"},{"@type":"ListItem","position":3,"name":"Internal medicine","item":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/"},{"@type":"ListItem","position":4,"name":"Nephrology","item":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/nephrology\/"},{"@type":"ListItem","position":5,"name":"Examinations in renal diseases (eGFR, proteinuria, haematuria, imaging, renal biopsy)"}]},{"@type":"WebSite","@id":"https:\/\/meddists.com\/learn\/#website","url":"https:\/\/meddists.com\/learn\/","name":"Meddists","description":"Let&#039;s Get Studying","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/meddists.com\/learn\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"}]}},"_links":{"self":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/7715","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/comments?post=7715"}],"version-history":[{"count":17,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/7715\/revisions"}],"predecessor-version":[{"id":9965,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/7715\/revisions\/9965"}],"up":[{"embeddable":true,"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/pages\/685"}],"wp:attachment":[{"href":"https:\/\/meddists.com\/learn\/wp-json\/wp\/v2\/media?parent=7715"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}