Common Symptoms and Investigations of Urinary system

Oliguria

Normal urine volume in 24 hours in health and in temperate climates is in a range of 800-2500 ml. A volume less than 400 ml is called oliguria.

Anuria : Urine volume < 100ml / 24 hours is called anuria

Polyuria : Urine volume > 3 litres / 24 hours is called polyuria.

Frequency

Is defined as the frequent passage of small quantities of urine without increase in the total volume.

Haematuria

It is into bleeding urinary tract from the urethra to the renal pelvis. When bleeding occurs mainly at the beginning or end of micturition, a prostatic or urethral origin is more likely.

Glomerular haematuria

Erythrocytes dysmorphic, MCV < 72 Fl

Presence of RBC casts

Concomitant proteinuria > 1 gm / day

Nonglomerular haematuria

Erythocytes isomorphic, MCV > 72 fl

Ansence of RBC casts

Proteinuria insignificant

Normal urine may contain 1 RBC per HPF.

Proteinuria

Daily excretion of more than 150 mg protein termed proteinuria (Normal adult may excrete upto 150 mg protein daily). Protein excretion more than 3.5 gm / 24 hours occurs in nephrotics.

The protein present normally in urine in filtered albumia (50%) and secreted Tam horsfall protein (50%). Proteinuria can be

(1) Over flow proteinuria

(2) Tubular proteinuria

(3) Glomerular proteinuria

(4) Orthostatic proteinuria

Overflow proteinuria occurs in monoclonal gammopathies like multiple myeloma where filtration protein load exceeds absorption capacity. Tubular proteinuria occurs in polycystic kidney, pyelonephritis, tuberculosis, analgesic nephropathy, nephrotoxic drugs, amyloidosis, analgesic nephropathy, nephrotoxic drugs, amylodosis, hyper calcemia, hypokalemia etc. Glomerlar proteinuria occurs in primary glomerulopathies, SLE, diabetes, Alport syndrome etc. Orthostatic proteinuria occurs in tall adolescents during activity but not in morning specimen. Transient proteinuria occurs in fever, and after exercise.

Tubular proteinuria nonseletive i.e. contains more gloubulin than albumin. Reverse is true for glomcrular proteinuria. In former albumin : P₂macroglobulin is upto 100:1 but in later > 1000 : 1, Microalbuminuria refers to daily albumin excretion of 30-300 mg.

Specific Gravity of Urine

It is a measure of the quantity of solids in solution and is an approximate measure of osmolaity. This also indicates the ability of the kidneys to concentrate or dilute urine. In a healthy person the specific ravity of urine is 1.020 or above. In chronic renal disease, the progressive diminution in the ability of the kidneys to concentrate or dilute rine (due to progressive renal destruction), finally fixes the specific gravity at 1.010 (isothenuria)

Haemoglobinuria

It is diagnosed when urine gives the chemical tests for haemoglobin, but no RBC is detected in microscpic examination of urine. This occurs in intravascular haemolytic disorders.

Porphyria

Is presence of prophobilinogen in urine, i.e. urine turns to dark red colour after standing hours e.g. Acute intermittent porphyria.

Casts and Crystals in urine

A.   Hyaline casts are found in :  Chronic glomerulo nephritis, pre-renal azotemia, obstructive uropathy.

B.   Brownish pigment cellular casts : Acute tubular necrosis (ATN)

C.   RBC casts  : Acute glomerulo nephritis

D.   Esoinophilic casts : Allergic interstitial nephritis

E.    Broad casts (more than 2-3 WBC diameter) : Chronic renal failure (CRF)

F.    Uric acid crystas : acute uric acid nephropathy

G.   Oxallc acid / hippuric acid crytstas : Ethylene glycol toxicity.

pH of urine

Normal pH of urine is below 5.5. In certain disease affecting predominantly the renal tubules, the urine can not be adequately acidified, ever though the glomerular filtration rate is normal.

Blood urea to creatinine ratio

Normally this ratio is 10:1

The ratio rises in

Depletion of extra cellular fluid volume

Tetracycline administration

Adrenocortical steroid therapy

Normal level of blood urea and serum creatinine are (15-40 mg/dl) and (0.7 – 1.2 mg / dl) respectively. Plasma concentration of creatinine correlatesx with the glomerular filtration rate (GFR) better than blood urea. GFR must be reduced by upto two thirds before the plasma urea and creatinine concentrations become elevated.

Glomerular filtration rate

The renal clearance of a substance is the smallest volume of plasma from which he amount of that removed substance is removed in the urine each minute. If the substance is removed by only glomerular filtration and is neither secreted nor reabsorbed by the tubules, its clearance is equal to the glomerular filtration rate. The clearance of endogenous creatinine is propular as a reasonably good index of GFR. Normal GFR is 120 ml / minute.

 Methods of Calculation of GFR

                                                             UV

     Clearance L (GFR)        =   —————            

                                                               P

U is the concentration of cretinine in urine (Value / Litre), V is the volume of urine produced (in ml / min), P is the plasma cretinine (Value / Litre), A 24 hour urine is collected and a blood sample for creatinine is taken during the day of collection.

                                     145 – Age in years

(2)     In Males     —————————–

                                       Serum creatinine

                                         145 – age in years –                        85     

(3)     In Females—————————–       X          ——-   

                                        Serum creatinine                            100

          Isotopes studies

The rate of disappearance of ⁵¹Cr EDTA or certain other isotopes from the circulation is an accurate measure of GFR.

Imaging of Urinary System

 Plain  X-Ray abdomen KUB

(Kidney, Ureter, Bladder) shows

Radio-opaque calculi if > 1cm diameter

Nephro calcinosis

Intravenous urography (IVU)

It is done by injecting cornary 420 that shows : pelvicalyceal system, ureters and bladder, calicification, cavitation, bilateral or unilaternal renal enlargement, hydrocalyx, hydronephrosis, hydroureter etc.

Retrograde urography or pyelogrphy

Micturating cystogram

A contrast medium is injected through the catheter, To see vesico-ureteric reflux Posterior urethral valves.

Renal angiography

To rule out renal mass, renal artery stenosis micro-aneurysms in kidney.

Ultrasonogrpahy

C.T. Scan and MRI.

Radioisotope studies for GFR of each kidney

Cystourethrosopy 

for bladder tumor, posterior urethral valves, bladder, bladder tuberculosis etc.

Urodynamic studies

These are indicated in urethral and bladder neck obstruction as in urethrel stricture, prostatic hypertrophy, neurogenic as in urethrel stricture, prostatic hypertrophy, neurogenic bladder dysfunction, posterior urethral valves.

I U V  Picture in Renal Diseases

Renovascular hypertension

Unilateral delayed appearance and excretion

Difference in size of kidney > 1.5 cms

Irregular contour of renal silhouette

Indentation on ureter of renal pelvis

Hyper concentration of contrast is smaller kidney (affected side)

Chronic pyelonephritis

Normal in early disease

Bilateral small kidney with irregular outlines

Calyceal blundting or dilatation

Cortical scarring

Diffuse renal disease with reduced function

Faint nephrogram phase

Small kidneys may be seen

Chronic urinary obstruction

Clubbed calyces

Slow excretion

Distention of pelvis

Thinning of renal cortex

Absence of calyceal opacification (negative pyelogram)

Renal tuberculosis

Calcification

Cavitation

Papillary necrosis

Medullary sponge kidney

Papillary blush

Pools or streaks of contrast medium within pyramids

No calyceal deformity

Small pyramidal cysts

Nephro calcinosis

Papillary concretions obscured by contrast medium

Contrast material remains separate from papillary concretions in retrograde pyelography

Polycystic kidney disease

Bilateral renal enlargement

Cayceal structure stretched and spidery

Elongated pelvis and flat calyces indented by cysts.

Rationale of Isotope Renal Scans

     1.131 Iodo-hippuran

80% excreted by renal tubular secretion

Helps toassess effective renal plasma flow and, thereby, functional status of renal homograft.

Renography may be useful in follow-up of diagnosed obstructive uropathy and /or assessment of pelviureteric junction obstruction.

      2. 99m Tc-labelled contrast agents

Helpes to assess renal perfusion

Useful in confirming inetrgrity of post-transplant vascular anastomosis (dynamic-vascular phase – studies)

Demonstration of gross hypoperfusion in a non-functioning transplant favours rejection rather than tubular necrosis.

Dynamic studies may also be useful in assessment of suspected renovascular rauma.

Static (parechymal phase) studies may be useful in the delineation of renal cortical function in the presence of severe renal failure (more sensitive than IVP), and also in the evaluation of suspected intrarenal trauma. 

3.   67 Gallium

           Helpful in excluding gradt infection, usually in conjunction with ultrasound and  / or transplant biopsy.

Radiographic nephrocalcinosis

    A. Coarse, medullary     

1. Primary hyperparaty-roidism

2. Primary renal tubular acidosis

3. Sarcoidosis, Milk alkali syndrome

4. Primary hyperoxaluria (Oxalosis)

5. Idiopathic ypercacuria, Idiopathic

      B.  Localized

1. Medullary sponge kidney (calcified collecting ducts)

2. Renal neoplasm

3. Cyst or haematoma

4. Papillary necrosis

5. Tuberculosis

6. Hydatid cyst.

      C.Diffuse cortical (Rare)

1. Chronic glomeruulonephritis

2. Old cortical necrosis

Causes of Polyuria

I.       Diabetes Insipidus

Antidiuretic hormone deficiency

a)  Post hypophysectomy

b) Post pituitary ablation

c)  Post trauma

Nephrogenic (No response to ADH)

a) Pyelonephritis

b) Analgesic nephropathy

c) Multiple myeloma

d) Sarcoidosis

e) Obstructive uropathy

f) Renal Transplantation

g) Drugs or toxins (e.g. Lithium, demeclocylin, ethanol, dipheyl hydanatoin etc)

II.Congenital

a)  Hereditary nephrogenic diabetes insipidus

b) Polystic disease

c)  Medullary cystic disease

III. Diabetes Mellitus

IV. Solute diuresis

a.Chronic renal failure

b.Urea or mannitol infusion

c.Glucosuria

d.High protein tube feeding

e.Radiographic contrast agents

V.     Natriuretic syndromes

a)     Salt losing nephritis

b)    Diuretic phase of acute tubular necrosis (ATN)

c)     Diuretic agents

VI.     Hyper calcemic nephropathy

VII.   Potassium depletion

VIII.Primary polydipis

IX.  Idiopathic

Causes of Haematuria

Renal Lesions

Glomerulo nephritis, pyelonephritis, renal tuberculosis, tubulo interstitial inhur, vaculitis and renal infract, hyperephroma, focal glomerulitis, IgA nephropathy, bacterial endocarditis, anticoagulant overdose, bleeding diathesis, trauma.

Renal Tract Lesions

Urinary tract stones, benign and malignant tumors, tuberculosis, acute cystitis or urethritis, trauma, prostatitis and prostatc tumor.

Causes of Dysuria

1.Infection – Acute bacterial cystitis, prostates, prostatao- cystitis

2.Benign prostatic hypertrophy (Old men)

3.Neurological disorders

4.Psychosomatic cystitis