IM - Renal Glomerular and Tubulointerstitial diseases

tonystep1's version from 2017-07-28 21:32

Primary Glormerular disease features

Question Answer
Minimal Change diseaseSingle most common form of nephrotic syndrome in children. Urinanalysis findings are benign ,but profound proteinuria and oval fat bodies. Children 40mg/h/m^2 proteinuria Adult 3.5g/h/m^2 proteinuria
Minimal Change disease EM Biopsy ResultNo histologic abnormalities on light microscopy; fusion of foot processes on electron microscopy
Primary Focal segmental glomerulosclerosis (FSGS)The condition causes asymptomatic proteinuria or nephrotic syndrome with or without renal insufficiency. Presenting with generalized edema, massive proteinuria, hypoalbuminemia, and hyperlipidemia.
Focal segmental glomerulosclerosis Biopsy ResultSegmentl solidification of the glomerular tuft
Membranous glomerulonephritisNephrotic ---Rule of thirds - 1/3 Spontaneous complete remission 1/3 persistent proteinuria of variable degree 1/3 Progressive disease, eventually leading to ESRD. - overwhelming majority of patients have edema or generalized anasarca
Membranous glomerulonephritis Biopsy resultlight microscopy shows diffuse subepithelial deposits
lgA nephropathy (Berger's disease)Asymptomatic recurrent hematuria/mild proteinuria is common. This is the most common cause of glomerular hematuria. Gross hematuria after an upper respiratory infection (or exercise) is common.
IgA nephropathy immunoflorescent Biopsy resultMesangial deposition of IgA and C3 are seen on electron microscopy.
Hereditary nephritis (Aiport's syndrome)X-linked or autosomal-dominant inheritance with variable penetrance Features include hematuria, pyuria, proteinuria, high-frequency hearing loss without deafness, progressive renal failure

Secondary Glomerular disease features

Question Answer
Diabetic nephropathyPersistent albuminuria (>300ug/d or >200ug/min) that is confirmed on at least 2 occasions 3-6 months apart. Progressive decline in the GFR. Elevated arterial blood pressure.
Diabetic nephropathy histologic changes1 Mesangial expansion 2 Thickening of glomerular basement membrane 3 glomerular sclerosis
Benign Hypertensive nephropathyResults in mild to moderate increase in Cr levels, microscopic hematuria, and mild proteinuria
Malignant Hypertensive NephrosclerosisCharacterized by a rapid decrease in renal function and accelerated HTN due to diffuse intrarenal vascular injury African-American men are the most susceptible
Lupus Nephropathyproteinuria >0.5 g!day (may have nephrotic syndrome) ; cellular casts;glomerulonephritis (may have hematuria) ; azotemia; pyuria; uremia; HTN
Membranoproliferative glomerulonephritisUsually due to hepatitis C infection; other causes include hepatitis B, syphilis, and lupus // Common association with cryoglobulinemia // The prognosis is poor. Renal failure develops in 50% of patients. Treatment is rarely effective.
Poststreptococcal GNThis occurs after infection with group A ,B-hemolytic streptococcal infection of the upper respiratory tract (or skin-impetigo) .// The GN develops about 10 to 14 days after infection. // Antistreptolysin-a may be elevated.
Goodpasture's syndromeClassic triad of proliferative GN (usually crescentic), pulmonary hemorrhage, and IgG anti-glomerular basement membrane antibody Clinical features include fever, myalgia, rapidly progressive renal failure, hemoptysis, cough, and dyspnea.
Sickle Cell NephropathyThis refers to a sickling of RBCs in the microvasculature, which leads to infarction, mostly in the renal papillae. Recurrent papillary infarction can lead to papillary necrosis, renal failure, and a high frequency of UTis.
H IV nephropathyCharacteristics include proteinuria, edema, and hematuria Histopathology resembles FSGS. Improvement is seen with prednisone, ACE inhibitors, and antiretroviral therapy.
Glomerulonephritis in endocarditisThis results from an immune-complex mechanism. However, a nonimmune mechanism (septic emboli, ischemia, antibiotic related) should be considered as well
Wegener's GranulomatosisVasculitis predominantly involving the kidneys and upper and lower respiratory tract (sometimes other organs as well) Laboratory findings: markedly elevated ESR; anemia (normochromic normocytic); hematuria; positive c-ANCA in 90% of patients
Polyarteritis nodosaEarly symptoms are fever, weakness, weight loss, myalgias and arthralgias, and abdominal pain (bowel angina) Diagnosis is made by biopsy of involved tissue or mesenteric angiography ESR is usually elevated, and p-ANCA may be present.


Question Answer
Acute Interstitial Nephritis (AIN)Acute allergic reaction to a medication is the most common cause--e.g., penicillins, NSAIDs, diuretics (furosemide, thiazide) , anticoagulants, phenytoin, sulfonamides//causes ARF and its associated symptoms//Rash, fever, and eosinophilia are classic findings//Eosinophils in the urine suggest the diagnosis, given the proper history and findings.
Chronic Interstitial Nephritisslowl and progressive condition that can lead to progressive scarring of the interstitium, renal failure, and ESRD over time (years)//here are no signs or symptoms of hypersensitivity//Causes include prolonged urinary tract obstruction, reflux nephropathy, heavy use of analgesics, heavy metal exposure (lead, cadmium) , and arteriolar nephrosclerosis with associated HTN.
Renal Papillary NecrosisMost commonly associated with analgesic nephropathy, diabetic nephropathy, sickle cell disease, urinary tract obstruction, UTI, chronic alcoholism, and renal transplant rejection//Diagnosis is typically made by excretory urogram
Renal Tubular Acidosis (RTA)Type 1Leads to hypokalemic, hyperchloremic, non-anion gap metabolic acidosis//Renal stones/nephrocalcinosis (due to increased calcium and phosphate excretion into alkaline urine)//Rickets/osteomalacia in children
Renal Tubular Acidosis (RTA) Type 2Characterized by hypokalemic, hyperchloremic non-anion gap metabolic acidosis//Nephrolithiasis and nephrocalcinosis do not occur//Fanconi's syndrome (in children)
Renal Tubular Acidosis (RTA) Type 4It is common in patients with interstitial renal disease and diabetic nephropathy//hyperkalemia and acidic urine//non-anion gap metabolic acidosis//Nephrolithiasis and nephrocalcinosis are rare
Hartnup SyndromeClinical features are similar to those of pellagra: dermatitis, diarrhea, ataxia, and psychiatric disturbances.
Fanconi's SyndromeIt is associated with glucosuria, phosphaturia (leads to skeletal problems: rickets/impaired growth in children; osteomalacia, osteoporosis, and pathologic fractures in adults), proteinuria, polyuria, dehydration type 2 RTA, hypercalciuria, and hypokalemia.


Question Answer
Acute Interstitial Nephritis (AIN)Inflammation involving interstitium (tissue that surrounds glomeruli and tubules)//Acute allergic reaction to a medication is the most common cause
Chronic Interstitial Nephritisprogressive scarring of the interstitium, renal failure, and ESRD over time (years)//there are no signs or symptoms of hypersensitivity
Renal Papillary NecrosisSloughed, necrotic papillae can cause ureteral obstruction//Most commonly associated with analgesic nephropathy, diabetic nephropathy, sickle cell disease, urinary tract obstruction, UTI, chronic alcoholism, and renal transplant rejection
Renal Tubular Acidosis (RTA)Type 1The defect is an inability to secrete H+ at the distal tubule (therefore new bicarbonate cannot be generated). This inability to acidify the urine results in metabolic acidosis. Although normally the urine pH can be as low as 4.7,
Renal Tubular Acidosis (RTA)Type 2The defect is an inability to reabsorb HC03- at the proximal tubule, resulting in increased excretion of bicarbonate in the urine and metabolic acidosis. The patient also loses K+ and Na+ in the urine
Renal Tubular Acidosis (RTA)Type 4This can result from any condition that is associated with hypoaldosteronism, or increased renal resistance to aldosterone.//It is characterized by decreased Na+ absorption and decreased H+ and K+ secretion in the distal tubule.
Hartnup SyndromeAutosomal recessive inheritance of defective amino acid transporter//Results in decreased intestinal and renal reabsorption o f neutral amino acids, such as tryptophan, causing nicotinamide deficiency
Fanconi's SyndromeFanconi's syndrome is a hereditary or acquired proximal tubule dysfunction that leads to defective transport of some of the following: glucose, amino acids, sodium, potassium, phosphate, uric acid, and bicarbonate.


Question Answer
Acute Interstitial Nephritis (AIN)Removing the offending agent is usually enough to reverse the clinical findings.
Chronic Interstitial NephritisAnalgesic nephropathy--Treatment of analgesic nephropathy is supportive and also includes discontinuation of analgesic use///Cyclosporine/tacrolimus--induced renal failure educe the cyclosporine/tacrolimus doses and target trough levels. Discontinuing these medications and/or switching to other immunosuppressives (eg, rapamycin), especially in those with more advanced renal failure, should also be considered.///Lead nephropathy-- Body burden of lead and bone lead concentration can be reduced by extended chelation treatment using ethylenediaminetetraacetic acid (EDTA) (versenate).
Renal Papillary NecrosisTreat the underlying cause, and stop the offending agents-- commonly associated with analgesic nephropathy, diabetic nephropathy, sickle cell disease, urinary tract obstruction, UTI, chronic alcoholism, and renal transplant rejection
Renal Tubular Acidosis RTA Type 1Correct acidosis with sodium bicarbonate. This can also help prevent kidney stones, which is a major goal of therapy. Administer phosphate salts (promotes excretion of titratable acid).
Renal Tubular Acidosis RTA Type 2Do not give bicarbonate to correct the acidosis because it will be excreted in the urine.//Sodium restriction increases sodium reabsorption (and thus bicarbonate reabsorption) in the proximal tubule.
Renal Tubular Acidosis RTA Type 4Hyperkalemia is treated with volume expansion, dietary potassium restriction, and potassium-wasting diuretics (eg, furosemide 20 to 40 mg po once/day or bid titrated to effect). Alkalinization is often unnecessary.
Hartnup SyndromeGive supplemental nicotinamide if the patient is symptomatic.
Fanconi's SyndromeTreat with phosphate, potassium, alkali and salt supplementation, as well as adequate hydration.