Sandbox : anmol

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Anmol Pitliya, M.B.B.S. M.D.[2]

Differential Oliguria

Classification by etiology	Etiology	Clinical manifestations										Paraclinical findings											Comments
		Symptoms and signs										Lab findings						Imaging
		Fatigue/Lethargy	Thirst	Dizziness/Confusion	Muscle weakness/cramp	Somatic/visceral pain	Vomiting	Diarrhea	Tachypnea	Haematuria/Proteinuria	Edema	Blood tests	Renal Funtion test	Electrolytes	Urine analysis	ABG	Other	Ultrasound	X-ray	CT	MRI	Other
Prerenal
	Myocarditis	+/-	-	-	-	+/-	-	-	+/-	-	-	Leukocytosis may be with eosinophilia Elevated ESR and CRP	-	-	-	-	Screening for rheumatic origin of disease Cardiac enzymes to rule out infraction Serum viral antibodies to rule out viral myocarditis, including: Coxsackie virus group B Human immunodeficiency virus (HIV), Cytomegalovirus Ebstein-Barr virus Hepatitis virus Influenza virus	-	-	-	Gadolinium-enhanced magnetic resonance imaging can detect inflammatory edema Delayed-enhanced MRI has also been to assess the degree of scarring	Endomyocardial biopsy is the gold standard for the diagnosis of myocarditis Echocardiography is useful for the following: Exclusion of amyloidosis, congenital and/or valvular diseases Assessment of cardiac dysfunction Detection of inflammatory origin, wall motion abnormalities, wall thickening, and pericardial effusion Distinction between fulminant and acute myocarditis Scintigraphy is useful for detecting myocardial inflammation ECG is non-specific but may detect the following: Heart block Ventricular arrhythmias Injury patterns, including those of myocardial ischemia and pericarditis
	Peritonitis	+/-	-	+/-	-	+/-	+/-	+/-	-	-	-	-	-	-	-	-	Peritoneal fluid analysis is the most important component of diagnosis and demonstrates the following: Ascitic fluid neutrophil count > 500 cells/µL	-	-	-	-	-
	Perinatal asphyxia	+/-	-	+/-	-	-	+/-	-	+/-	-	-	May indicate infection, hemorrhage or thrombocytopenia	Decreased glomerular filtration rate Elevated creatinine >1.5 mg/dL	-	-	Elevated cardiac troponin T and I levels are specific for cardiac dysfunction Neutrophil gelatinase-associated lipocalin is under investigation as a biomarker for acute kidney injury Fetal umbilical artery pH <7.0 Elevated liver transaminases Coagulation profile should be carried out	-	Cranial ultrasound may indicate the following: Focal hemorrhage Ventricular dilatation White matter damage Cerebral edema Cystic lesions	X -ray may demonstrate the following: Cardiomegaly Hazy lung fields indicating pulmonary edema	-	Acute brain injury may be seen on MRI	ECG may demonstrate ischemia with changes in the ST segment Echocardiography may demonstrate the following: Decreased left ventricular ejection fraction Right-to-left atrial shunting	Apgar score is very important during assessment
	Polycythemia	+/-	-	-	-	-	-	-	+/-	-	-	Hematocrit > 49% in men Hematocrit > 48% in women Hemoglobin > 16.5 g/dL in men Hemoglobin > 16 g/dL in women Total red blood cell mass ≥ 36 mL/kg in males Total red blood cell mass ≥ 32 mL/kg in females Thrombocytosis > 400,000/μL Leukocytosis with predominant neutrophils > 12,000/μL Leukocyte alkaline phosphatase >100 U/L Serum vitamin B-12 concentration >900 pg/mL Hyperuricemia may be present	Decreased erythropoietin	-	Oxygen saturation ≥ 92%	-	May demonstrate splenomegaly	May demonstrate splenomegaly	-	-	-	JAK2 mutation Bone marrow biopsy demonstrates: Hypercellularity with hyperplasia of the erythroid, granulocytic, and megakaryocytic cell lines Myelofibrosis may also be present Prothrombin time and activated partial thromboplastin time may be prolonged	Phlebotomy is the usual form of treatment
	Respiratory distress syndrome	+	-	+/-	-	-	-	-	+	-	-	-	-	-	-	Metabolic and respiratory acidosis may occur with hypoxia	Pulse oximetry is useful in diagnosis	-	Demonstrates the following: Bilateral, diffuse, reticular granular or ground-glass appearance Poor lung expansion Cardiomegaly may or may not be present Streaky opacities may indicate pneumonia	-	-	Echocardiography is useful in diagnosing patent ductus arteriosus
	Shock - Anaphylactic - Cardiogenic - Hypotensive - Septic - Toxic	+/-	+/-	+/-	+/-	+/-	+/-	-	+/-	+/-	-	Elevated hemotocrit value may indicate hypovolemic shock Anemia and/or thrombocytopenia may indicate hemorrhagic shock Elevated eosinophils may indicate anaphylactic shock Elevated leukocytes may suggest septic shock A low white count with bandemia may suggest an undifferentiated shock	Elevated BUN and creatinine Decreased GFR	Hypernatremia or hyponatremia Hypokalemia or hyperkalemia Hypochloremia	-	Elevated serum lactate	Cross matching and blood typing of blood is important for blood transfusion Prolonged prothrombin and activated partial thromboplastin time may indicate hemorrhagic shock Elevated liver transaminases In cardiogenic shock: Elevated troponin I or troponin T levels Elevated creatine phosphokinase Elevated brain natriuretic peptide, or N-terminal pro-brain natriuretic peptide Disseminated intravascular coagulopathy may occur as a complication, and is determined through elevated fibrin split products and D-dimer level with low fibrinogen level	RUSH (Rapid ultrasound in shock) may detect the following: Pulmonary embolism Pericardial effusion Cardiac tamponade Reduced contractility of the right and left ventricle Pneumothorax Pulmonary edema Thoracic or abdominal aortic aneurysm	May demonstrate the following: Pneumonia Pneumothorax Pulmonary edema Widened mediastinum Free air under the diaphragm May also determine etiology of shock, such as: Intestinal obstruction Bowel perforation	Can determine etiology of shock, such as: Traumatic brain injury, Stroke Spinal injury Pneumonia Pneumothorax Ruptured aneurysm Aortic dissection Intestinal obstruction Bowel perforation Abscess Pulmonary embolism	-	-
	Third space losses - Capillary leak - Surgery - Trauma	+/-	+/-	+/-	+/-	+/-	+/-	-	+/-	+/-	-	Normocytic normochromic anemia Decreased hematocrit	Elevated BUN and creatinine Elevated GFR	May demonstrate proteinuria or hematuria	Elevated lactate dehydrogenase Elevated alkaline phosphatase Hypo or hypernatremia Hypo or hyperkalemia	May visualize fluid collections	More accurately visualize the following: Margins of trauma Fluid collection	Useful for diagnosis of soft tissue injury	-	-	-
	Toxic megacolon	+/-	+/-	+/-	-	+	+	+/-	-	-	-	Leukocytosis with left shift Anemia (if diarrhea is present)	Creatinine and BUN may be elevated	-	Hyponatremia is common	Elevated ESR and CRP	Ultrasound may demonstrate the following: Loss of haustra Hypoechoic and thick bowel walls Dilated colon > 6cm Dilatation of ileal loops Presence of intraluminal gas and fluid	The following is noted with x-ray: Dilated colon Loss of haustra Soft tissue masses Segmental parietal thinning Free intraperitoneal air	May demonstrate the following: Bowel perforation Abscess	-	-	Endoscopy and colonoscopy can aid diagnosis
	Classification by etiology	Etiology	Clinical manifestations										Paraclinical findings											Comments
			Symptoms and signs										Lab findings						Imaging
			Fatigue/Lethargy	Thirst	Dizziness/Confusion	Muscle weakness/cramp	Somatic/visceral pain	Vomiting	Diarrhea	Tachypnea	Haematuria/Proteinuria	Edema	CBC	KFT	Electrolytes	Urine analysis	ABG	Other	Ultrasound	X-ray	CT	MRI	Other
	Intrinsic renal	Acute interstitial nephritis	+/-	-	+/-	-	+/-	+/-	+/-	+/-	+/-	+/-	Eosinophilia may be present	Elevated creatinine High fractional sodium excretion	-	Eosinophiluria Sterile pyuria Microscopic hematuria Proteinuria Red cell or white cell casts	-	Patients with immunoglobulin G4 - related disease may have elevated serum total IgG and/or IgG4 levels	Ultrasound demonstrates normal-sized kidneys	-	-	-	-	History of long term analgesic use is common
		Acute tubular necrosis	+/-	-	-	-	-	+/-	-	-	+/-	+/-	Anemia	Elevated creatinine Elevated BUN Elevated fractional excretion of sodium	Hyponatremia Hyperkalemia Hypermagnesemia Hypocalcemia Hyperphosphatemia	Pigmented, muddy brown, granular casts	-	-	Ultrasound can determine: Obstructive uropathy Renal size Cortical thickness Hydronephrosis	May be useful in cases with nephrolithiasis	May be useful in cases with nephrolithiasis May also determine area of obstruction	May also determine area of obstruction	Renal biopsy may demonstrate the following: Loss of tubular cells or the denuded tubules Swollen tubular cells Loss of the cell brush border Useful kidney function biomarkers: Neutrophil gelatinase-associated lipocalin Interleukin-18 Kidney injury molecule 1 Cystatin C Sodium/hydrogen exchanger isoform 3	Furosemide stress testing can predict stage
		Cancer - Renal cell carcinoma - Metastatic cancer	+	-	-	-	+/-	+/-	-	-	+	+/-	May reveal normocytic or microcytic anemia Leukocytosis or lymphocytosis Elevated reticulocytes Thrombocytopenia Leukopenia Blast cells	Elevated BUN Elevated creatinine Decreased GFR Decreased or increased production of erythropoietin	Hyponatremia Hypomagnesemia Hyper or hypocalcemia Hypophosphatemia Hyper or hypokalemia	Gross hematuria	-	Elevated liver transaminases	Ultrasound can detect fluid collection and morphologic change Flank mass	Can delineate tumor, visualize calcification and widened mediastinae Barium contrast may show filling defects	May accurately visualize metastasis and determine staging Distinguish cystic from solid masses Determine lymph node, renal vein, and inferior vena cava involvement	May determine soft tissue invasion and staging	Percutaneous cyst puncture may aid diagnosis of malignant cystic lesions	Histology can determine type of cancer Renal cell carcinoma can be divided into the following types: Clear cell (75%) Chromophilic (15%) Chromophobic (5%) Oncocytoma (3%) Collecting duct (2%)
		Chronic kidney failure	+	-	-	-	+/-	-	-	-	+	+	Anemia is present	Elevated creatinine Elevated BUN Decreased GFR	Hyperkalemia	Hypoalbuminuria	Low bicarbonate	To determine renal bone disease, the following may be performed: Serum phosphate 25 - hydroxyvitamin D Alkaline phosphatase Parathyroid hormone To determine kidney function, C - cystatin may be measured	May indicate hydronephrosis Retroperitoneal fibrosis Mass Enlarged or shrunken kidneys	May demonstrate nephrolithiasis Retrograde pyelogram may determine obstruction	May determine renal masses, stones, and cysts	Useful in those who are contraindicated for intravenous contrast May determine renal vein thrombosis Magnetic resonance angiography can diagnose renal artery stenosis	Percutaneous renal biopsy is also useful in diagnosis
		Congenital kidney disease - Agenesis - Dysplasia - Hypoplasia - Polycystic	+/-	-	-	-	+/-	+/-	-	-	+/-	+/-	Elevated hematocrit	Decreased GFR	Hypocalcemia Hypophosphatemia	Microalbuminuria Uricosuria	-	Genetic testing for ADPKD1 and ADPKD2	Ultrasound is the gold standard for visualization of cysts	More sensitive than ultrasound and can detect small cysts (0.5 cm)	Useful for determining kidney size and progression Magnetic resonance angiography may determine intracranial aneurysms	-	-
		End stage renal disease	+	-	-	-	+/-	-	-	-	+	+		Elevated creatinine Elevated BUN Decreased GFR	Hyperkalemia	Hypoalbuminuria	Low bicarbonate	To determine renal bone disease, the following may be performed: Serum phosphate 25 - hydroxyvitamin D Alkaline phosphatase Parathyroid hormone To determine kidney function, C - cystatin may be measured	May indicate hydronephrosis Retroperitoneal fibrosis Mass Enlarged or shrunken kidneys	May demonstrate nephrolithiasis Retrograde pyelogram may determine obstruction	May determine renal masses, stones, and cysts	Useful in those who are contraindicated for intravenous contrast May determine renal vein thrombosis Magnetic resonance angiography can diagnose [[[renal artery stenosis]]	Percutaneous renal biopsy is also useful in diagnosis
		Endogenous toxins - Hemoglobin - Myoglobin - Uric acid	+/-	-	+/-	+	-	+/-	-	-	+/-	+/-	May indicate anemia or thrombocytopenia	Elevated BUN Elevated creatinine Decreased GFR	Hyperkalemia Hypocalcemia due to hyperphosphatemia Hyperuricemia	Uricosuria Hematuria Myoglobinuria Casts Urinary sediment	-	Elevated creatine kinase > 1000 U/L	Ultrasound may determine the following: Malignant or cystic lesions Hydronephrosis Hydroureter Nephrocalcinosis Urolithiasis	-	Spiral CT may determine the following: Urolithiasis Wilms tumor Polycystic kidney disease	-	Voiding cystourethrograms may detect ureter or bladder abnormalities Radionuclide studies may visualize calculi
		Glomerulonephritis	+/-	-	-	-	-	-	-	-	+	+	Pleocytosis Anemia Leukocytosis	Elevated BUN and creatinine	-	Specific gravity > 1.020 Proteinuria Hematuria Red blood cell casts White blood cell casts Dysmorphic RBCs Acanthocytes Cellular casts Granular casts Oval fat bodies	-	-	Elevated ESR Elevated complement C3, C4, CH50 Streptozyme test to screen for streptococcal antigens Blood and tissue culture may aid diagnosis Other useful tests include: Antinuclear antibodies Anti-DNA antibodies Cryoglobulins Serum albumin Triglyceride levels Hepatitis B and C serologies Antineutrophil cytoplasmic antibody (ANCA)	May determine the following: Kidney size Echogenicity of the renal cortex Obstruction Degree of fibrosis	To exclude the following: Granulomatosis with polyangiitis (Wegener granulomatosis) Goodpasture syndrome Pulmonary congestion	To exclude the following: Granulomatosis with polyangiitis (Wegener granulomatosis) Goodpasture syndrome Pulmonary congestion To visualize visceral abscesses	-	Renal biopsy may aid diagnosis Light and electron microscopy may have specific findings and determine pathology Immunofluorescence may also exhibit diagnostic findings
		Goodpasture syndrome	+/-	-	-	-	-	-	-	+/-	+/-	+/-	Anemia Leukocytosis	Elevated BUN Elevated creatinine	-	Low-grade proteinuria Gross or microscopic hematuria [[Red blood cell] casts	-	Anti– glomerular basement membrane antibody testing is positive by radioimmunoassays or enzyme-linked immunosorbent assays Antineutrophilic cytoplasmic antibody testing is positive for c- or p- ANCA Elevated ESR	-	Bilateral, basal, patchy parenchymal consolidations	-	-	Pulmonary biopsy will demonstrate diffuse alveolar hemorrhage
		Hemolytic uremic syndrome	+/-	-	+/-	+/-	+/-	+	+	-	+/-	+/-	Severe anemia Thrombocytopenia	Elevated BUN Elevated creatinine	-	Mild proteinuria Red blood cells Red blood cell casts	-	Peripheral blood smear demonstrates schistocytes Prolonged activated partial thromboplastin time Elevated fibrinogen degradation product and D-dimer Elevated bilirubin Elevated lactate dehydrogenase Decreased haptoglobin Stool culture may be postive for E coli 0157:H7 or shigella ADAMTS-13 activity is severely decreased	Helpful in ruling out obstruction	-	-	-	Renal biopsy may demonstrate the following: Diffuse thickening of the glomerular capillary wall Swelling of endothelial cells Fibrin thrombi
		Nephrolithiasis	-	-	-	-	+/-	+/-	-	-	-	-	Mild leukocytosis	Elevated creatinine Elevated BUN	Hypercalcemia Hyper or hyponatremia Hyper or hypokalemia Hyperuricemia	Gross or microscopic hematuria Red blood cells or white blood cells Pyuria Urinary crystals of calcium oxalate, uric acid, or cystine Hypercalciuria Urinary pH > 7 may indicate an infection with urea-splitting bacteria such as: Proteus Pseudomonas Klebsiella, and may lead to struvite stones Urinary pH < 5 indicates likely formation of uric acid stones	Decreased serum bicarbonate with hypokalemia may indicate renal tubular acidosis	Elevated CRP	All types of stones are visible May demonstrate the following: Hydronephrosis Ureteral dilation Abdominal aortic aneurysm Cholelithiasis Safe in pregnancy but may miss small stones	Calcium - containing stones are radio-opaque Uric acid or cystine stones are radiolucent Plain or KUB (kidney-ureter-bladder) radiograph may determine stone characteristics such as: Size Shape Composition Location Differentiate between a phlebolith and an obstructing calcific stone Stone movement may also be monitored	Most sensitive modality for renal stones Can estimate stone density, size and composition CT is able to determine pathology secondary to renal stones, such as: Ureteral dilation Hydronephrosis Nephromegaly Perinephric fat streaking No contrast needed and can diagnose other pathologies, such as: Abdominal aortic aneurysm Appendicitis Pancreatitis Cholecystitis Ovarian disorders Diverticular disease Renal cell carcinoma	-	Intravenous pyelography (IVP) visualizes entire urinary system and is gold standard for the diagnosis of ureterolithiasis Renal tomography can determine similar findings as CT, however has been largely replaced by CT Nuclear renal scan can determine renal function
Nephrotic syndrome		+/-	-	-	-	-	+/-	-	-	+	+/-	-	Serum creatinine is normal in uncomplicated nephrotic syndrome Serum albumin is decreased	-	Proteinuria > 3.5g/day The following may or may not be present Waxy casts Oval fat bodies Fatty casts Granular casts Microhematuria Dysmorphic RBCs	-	Genetic screening for NPHS1 and NPHS2 mutations Renal biopsy aids diagnosis Other useful tests: Hepatitis B and C HIV Syphilis Antinuclear antibody Anti–double stranded DNA antibodies Complement Absence of phospholipase A2 receptor may indicate secondary nephrotic syndrome	Ultrasound scanning may demonstrate focal glomerulosclerosis	-	-	-	-	-
Thrombosis - Renal vein - Renal artery		-	-	-	-	+/-	+	-	-	+	+/-	-	Elevated creatinine Elevated BUN	-	-	-	Hypercholesterolemia Hypoalbuminemia Complementemia	Ultrasound may demonstrate the following: Echo-poor medullary pyramids	Visualizes the renal veins and is the modality of choice	Visualizes blood flow, vessel walls, and adjacent tissues	-	Renal biopsy, inferior vena cavography, and renal arteriography may aid diagnosis IVP may reveal an enlarged kidney
Transplant rejection		+/-	-	-	-	+	+/-	-	-	+/-	+/-	Lymphcytosis may be present Eosinophilia may occur	Acute elevation in serum creatinine	-	-	Proteinuria > 1g/day Pyuria may be present	-	Plasma levels of donor-derived cell-free DNA is elevated > 1% and is released from the dead cells of the graft Positive detection of complement split product C4d Elevated endothelial activation and injury transcripts	May demonstrate the following Increased graft (kidney) size Loss of corticomedullary boundary Hypoechoic pyramids Decreased echogenicity of renal sinuses May also demonstrate other pathologies: Ureteral obstruction Acute tubular necrosis Renal vein occlusion Pyelonephritis Cyclosporine toxicity	-	-	Acute antibody-mediated rejection will demonstrate the following on histology: Patchy mononuclear cell infiltrates Swollen endothelium Fibrinoid necrosis Presence of fibrin thrombi Cortical necrosis	Chronic rejection does not usually manifest with oliguria and/or anuria