This document provides an overview of urine analysis techniques and findings related to nephrology. It discusses urine dipstick testing and issues that can affect results. It also describes urine casts, crystals, and cells that may be seen during microscopic urine examination and what different findings indicate in terms of kidney conditions and diseases. Common bacteria that cause urinary tract infections are listed. Radiologic techniques used to evaluate the kidneys are briefly outlined.

1. Pete A. Gutierrez MD, MMS, PA-C Miami Dade College Physician Assistant Program March 2009

2. Nephrology Urine Analysis: Dip stick testing: Problems: Urine Ph may change with time Contamination may cause bacteria to multiply and convert nitrate to nitrite causing a false positive. At low specific gravity (Less than 1.010), cells lyse and casts from less readily. Cast also dissolve in alkaline Urine.

3. Nephrology Midstream Urine Collection Contamination more common in women than in men. Suprapubic aspiration is the more secure method of getting an Uncontaminated Urine Hematuria Flank Microscopic

4. Nephrology Urine Casts. Are formed from Tamm-Horsfall glycoprotein which is synthesized and secreted in the ascending limb of the loop of Henle and distal convoluted tubules. Physiologic Casts Hyaline are transparent and cylindrical and are seen in urine of normal subjects. Both can be increased by fever, exercise and volume depletion

5. Nephrology Pathologic casts: this may contain cellular material (erythrocytes, leukocytes, tubular cells, bacteria, or fungi) , fibrin, lipids, bile, and crystals. The most important is the erythrocytes, because it indicates glomerular bleeding. Those composed of polymorphonuclear leukocytes usually indicate renal parenchyma infection.

6. Nephrology Leukocytes in the urine means infection Renal tubular cells are found in the urine in acute tubular necrosis and acute interstitial nephritis Crystals of calcium oxalate and uric acid may be seen in normal urine however large bizarre crystals of any type including calcium oxalate and uric acid indicate calculus disease.

7. Nephrology IGA nephropathy: The most common form of primary glomerular disease in the world. It is particular prevalent in Asia, and Australia, and rare in African Americans. It originally thought to be benign. Now understood it will progress to renal failure in 20 to 40% of patients affected.

8. Nephrology Primary gross hematuria, No therapeutic regimen has been shown to clearly affect the outcome in IgA disease. However warfarin and dipyridamole with or without cyclophosphamide have been suggested as worthy of further investigation Also omega 3 fatty acids, ACE, and long term steroids are also on trial.

9. Nephrology Membranous nephropathy: Two thirds of patients with this disorder either have a spontaneous remission or have stable or very slow progressive renal insufficiency. Those with heavy proteinuria greater than 10 gram per day, hypertension, diminished GFR, male gender, don’t do well.

10. Nephrology Bacteria: Gram Negative E-Coli Klesbsiella Pneumoniae Proteus Enterobacter Pseudomonas

11. Nephrology Gram Positive Staphylococcus saprophyticus Staphylococcus aureus Staphylococcus not aureus Enterococci Other bacteria mixed Yeast

12. Nephrology Symptomatic UTI’s: Obstruction to urine flow. Congenital anomalies Renal Calculi Ureteral occlusion (partial or total). Vesicoureteral reflux Residual urine in bladder Neurogenic bladder Urethral stricture Prostatic hypertrophy

13. Nephrology Instrumentation of urinary tract; Indwelling urinary catheter Catheterization Urethral dilation cystoscopy

14. Nephrology Acute Urethral syndrome: Vaginitis approximately 20% of women in the United States have an episode of dysuria each year. (Candida is the most common cause). Urethritis most commonly cause by Chlamydia trachomatis Prostatitis The most common addiction in men causes dysuria and urinary frequency. (E. Coli).

15. Nephrology Pregnancy and the increases risk of UTI: 20-40% of which develop pyelonephritis. Either short acting sulfonamides or amoxicillin for 7 days usually suffices. Avoid Tetracycline, trimethropin and fluoroquinolones.

16. Nephrology Hypertensive disorders of pregnancy: Preeclampsia is characterized by, 1. Hypertension, proteinuria, edema, and at time coagulation and liver abnormalities usually occurring at about the (20) weeks of pregnancy. Primarily in nulliparas. Pressure of 140/90. Patient will go into convulsions and diet condition called eclampsia.

17. Nephrology Kidney function and morphology in preeclampsia: Both GFR and RPF decrease in preeclampsia. Uric acid increases in blood. Increased proteinuria. Calcium develop hypocalciuria Lesion at the glomerular capillary endotheliosis.

18. Nephrology Management of preeclampsia: Hospitalization rest and if signs of impeding eclampsia(hyperreflexia, headache, epigastric pain) develop termination of pregnancy should be considered. The drug of choice for impeding convulsion is parenteral magnesium sulfate.

19. Nephrology Regulation of blood pressure: Hydralazine administered intravenously is the drug of choice. (5mg as a bolus follow by 5-10mg every 20-30 minutes. Labetalol intravenously 20mg and repeat the dose every 20 minutes, up to 200 mg. Refrain from using nitroprusside.

20. Nephrology Use of Radiologic Techniques: KUB Intravenous pyelography (IVP) Stone, obstruction. (allergic reactions). Cystography (Bladder). Ultrasound Ct evaluation of renal disease MRI

21. Nephrology Renal angiography provides definitive diagnosis of renal arterial pathology

22. Nephrology Algorithm for treatment of hypertension: First line of therapy should be diuretic (thiazide). In patients with type I diabetes and proteinuria (Diabetic nephropathy) the treatment is with an ACE inhibitor. In patients with heart failure (Systolic dysfunction), ACE inhibitor or diuretic is indicated Beta blockers or Ca Channels blocker can them be use.

23. Nephrology Causes of resistant Hypertension: White coat Pseudohypertension in elderly persons Use of improper size blood pressure cuff. Patient non compliant Failure due to cost, side effects, or ignorance Dietary noncompliance Excess salts.

24. Nephrology Causes of resistant Hypertension: Excess ethanol intake Volume overload Failure to include diuretic Inadequate treatment Medication interactions. Nonsteroidal meds. Trycyclic antidepressants Cocaine or other illicit drugs

25. Nephrology Causes of resistant Hypertension: Associated co morbid conditions Obstructive sleep apnea Increasing obesity Anxiety induced hyperventilation or panic attacks.

26. Nephrology Causes of resistant Hypertension: Underlying secondary hypertension Reno vascular hypertension Primary renal parenchyma disease Primary Hyperaldosteronism Pheochromocytoma

27. Nephrology Evaluation of suspected renovascular hypertension: The principal cause is atheromatous narrowing of one or both main renal arteries, which occurs in older individuals, with a peak incidence in the sixth decade. Men are affected twice as often as women.

28. Nephrology A second type of lesion is the fibro muscular dysplasia (Hyperplasia) the lesion appears as a multifocal “string of beads,” beginning in the middle of the renal artery. Test of choice is the renal angiography. Treatment must be aggressive.

29. Nephrology Diuretics: Loop K-sparing Osmotic Carbonic anhydrase inhibitors

30. Nephrology Nephritis vs. Nephrotic: In Nephritis syndrome there is variable proteinuria and active urine sediment; dysmorphic RBC’s and WBC’s and casts of RBC, WBC, and granular material. (Remember that CASTS always originate in the renal tubules). Common causes of Nephritis syndrome are post infections GN, IgA Nephropathy, and Lupus Nephritis.

31. Nephrology Nephrotic Syndrome: Always heavy proteinuria, and urine fat. Nephrotic range proteinuria is >2.5-3.5gm/day. (Free fat droplets, oval fat bodies, fatty/waxy casts and renal tubular cells with lipid droplets). Nephrotic patients tend to get hypoalbuminemia (with 2 nd edema) and they develop tendency for more infections, especially with H. Influenza, and S. Pneumonia. Also low thyroid binding protein so low total thyroxine and iron levels.

32. Nephrology The Nephrotic patient also have severe hyperlipidemia. IgA Nephropathy most common >25%, also know as Berger Disease. It can present from hematuria alone Berger disease to Schonlein Henoch Purpura, which is found in children's, affecting the skin the kidneys and the joints. The Hematuria is usually present secondary to an infection or exercise.

33. Nephrology Membranoproliferative AGN: This presentation has both basement membrane and changes in cells proliferation. Presentation is similar to IgA with Hematuria with nephrotic range proteinuria and rapidly progressive glomerulonephritis, and may lead to renal failure. Rapidly Progressive AGN: Starts with azotemia, oliguria followed by diuresis in days to weeks after which the GFR usually returns to normal. Rapid progression to renal failure

34. Nephrology Diabetic Nephropathy: Is the second commonest cause of nephrotic range proteinuria. In develops in 30% of the adult population with type I Diabetes. First change in renal problems is micro albuminuria. Patients progress to full renal failure within 5-7 years. Need to control tight control of blood sugar level in order to prolong the disease process.

35. Nephrology Acute Intestitial diseases: They present with slight proteinuria < 2mg/d. Acute allergic interstitial nephritis (AIN) is a drug induced hypersensitivity problem and often presents with eosinophils. The most common drug is cimetidine, thiazides, phenytoin, and allopurinol. The most common antibiotics culprits are: Beta-Lactams like methicillin, TMP/SMX, and Rimfapin, also fluoroquinolones.

36. Nephrology Hereditary Kidney diseases: Alport Syndrome= nephritis can be either X-linked or AD with variable expression, men are affected more than females. Is a connective tissue defect(type IV collagen) which affect the basement membrane. Target is the same as Goodpasture syndrome with occasional deafness and lens problems. The female X l;inked had usually microscopic hematuria. Males have renal failure before age 50.

37. Nephrology Polycystic kidney disease: Autosomal dominant. Is the commonest genetic disease of the kidney. Usually associated with a mutation on the short arm of 16. Patients develop cysts in the kidneys, liver and pancreas and associated with recurrent hematuria. Progressive renal failure and HTN are the norm. Cerebral aneurism is a very small percent 1-5%. For kidneys infections use the lipid soluble antibiotics like trimethroprim, erythromycin, chloramphenicol, tetracycline, ciprofloxin and clindamycin.

38. Nephrology DKA: Occurs in 5% of patients with Type I DM. Laboratory shows increased ion gap. Metabolic acidosis, and positive serum ketones in the urine., with plasma glucose usually elevated. Hyonatremia, hyperkalemia, azotemia, and hyperosmolality are other findings. Clinical features: Nausea Vomiting And vaguely localized abdominal pain. Dehydration Respiratory shock Coma

39. Nephrology Management: ICU Replacement of fluids deficits of several liters. (subtracting present weight with known recent weight). At least one liter an hour Insulin therapy IV bolus of regular insulin at 10-15 units follow by an infusion of 10-15 units/hour. A decrease of 50-75 mg/dl/hour is an appropriate response.

40. Nephrology DKA continued: When serum bicarbonate rises to 15 mEq/L 1-2 units/hour of insulin is the goal. Start Dextrose %% should be infused once plasma glucose degreases to 250 mg/dl in order to prevent hypoglycemia. Potassium deficits can be restore by adding 10-20 mEq/hour in the IV fluids. Monitoring of blood glucose every 1-2 hours and arterial blood gases as often as necessary.

41. Nephrology Complications of DKA: Lactic acidosis Arterial thrombosis Cerebral Edema