INTRODUCTION AND CLINICAL MANIFESTATIONS OF RENAL DISEASE (1)

INTRODUCTION AND CLINICAL MANIFESTATIONS
OF
RENAL DISEASE (1)
LEARNING OBJECTIVES
 At the end of the lecture students should be able to
 Describe basic structure and functions of the kidney
 Illustrate main symptoms of renal disease
 Assess kidney functions
ANATOMY
• The kidneys are retroperitoneal
organs lie on either side of the spine at
level of T12-L3
• Normal kidneys are 11-14 cm in
length
• Right kidney lies 1.5 cm lower
than the left because of the liver
Each kidney contains one million
nephrons comprising a
glomerulus, PCT, Loop of
Henle, distal tubule and
collecting duct
Blood and nerve supply to the
kidney
•
•
•
The kidneys receive 25% of the cardiac output
T10-12/L1 roots innervate the renal capsule and the ureter
and pain from these structures is felt in these dermatomes
The Glomerulus
A glomerulus is a capillary tuft that is surrounded by
Bowman's capsule
Receives its blood supply from an afferent
arteriole Unlike most other capillary beds,
the glomerulus drains into an efferent
arteriole
The resistance of these arterioles results in high
pressure within the glomerulus, aiding the process of ultrafiltration,
where fluids are forced out of the capillaries
and into Bowman's capsule
Glomerulus and its surrounding Bowman's capsule
constitute a renal corpuscle, the basic filtration
unit of the kidney
The rate at which blood is filtered through all of the glomeruli, and thus
the measure of the overall renal function, is the glomerular filtration
rate (GFR).
THE GLOMERULAR LAYERS
Primary functions of the kidneys
 Excretion of waste products e.g. urea
 Maintain body water and electrolytes
 Regulation of BP through renin angiotensin system
 Endocrine function in erythropoiesis and vitamin D
metabolism
The kidneys produce urine which
passes to the bladder through
the ureters
As the bladder fills completely, the
smooth muscle layer (detrusor)
contracts under parasympathetic
control to allow urine to pass
through the urethra
Symptoms of renal disease
 Kidney (upper urinary tract symptoms): Pain
,swelling,hematuria
 Lower urinary tract symptoms: voiding pain (pain passing
urine), frequency, urgency, hesitancy
 Change in urine volume (polyuria, oliguria, anuria) or color
(haematuria), content (proteinuria)
 General symptoms: oedema, fatigue, nausea, vomiting,
shortness of breath
Kidney (Upper urinary tract) symptoms
Pain
•
•
•
•
•
Renal colic
A severe sudden sustained loin
pain
It often radiates to the groin
It is caused by sudden obstruction
in the urinary tract usually by a calculus or a blood clot
It is often associated with nausea and vomiting may be
associated with smokey urine.
B.Dull ache in the loins
•
•
•
Usually due to stretch of the capsule of the kidney e.g. in
glomerulonephritis, polycystic kidney and
hydronephrosis
Loin pain with fever, rigors, pain on voiding suggest
infection of the kidneys (acute pyelonephritis)
Many patients with chronic obstruction are however
pain-free
Lower urinary tract symptoms
Dysuria
•
•
Pain or discomfort felt during or immediately after passing
urine
It is often described as a burning sensation felt at the urethral
meatus , or the suprapubic region
•
The most common cause is infection and /or inflammation of
the bladder[cystitis]and frequency(desire to pass urine more
often) is usually present
Voiding symptoms
•
During storage phase
•
During voiding phase
•
After micturition
•
Incontinence
Urgency
•
Storage symptoms
A sudden strong need to pass urine and may cause
incontinence if there is no opportunity to urinate. Is due to
overactivity of detrusor muscle or abnormal stretch receptor
activity from the bladder
Frequency
•
Means frequent micturition of relatively small amounts of
urine
•
•
•
•
•
Causes
Cystitis, urthritis or stone bladder causing irritation of the
bladder wall
Contracted bladder as occurs in Bilharziasis; the diminished
capacity of the bladder leads to frequent micturition
Chronic retention of urine e.g. by enlarged prostate small
amount of urine overflow from the bladder at frequent
intervals
Cancer bladder
Psychogenic factors as anxiety.
Voiding phase symptoms
 Hesitancy: delay or difficulty in initiating urine flow
 In men over 40, it is commonly due to bladder outlet
obstruction by prostate enlargement
 In women, it suggests urethral obstruction due to
stenosis or uterine prolapse
 Poor flow: reduction in urinary stream
After micturation symptoms
•
Dribbling and incomplete emptying are caused by
obstruction
•
•
•
Incontinence : involuntary release of urine may occur
With the need to void (urge incontinence) caused by
overactive detrusor
or with increased intra abdominal pressure (stress
incontinence) due to weakness of pelvic floor following
childbirth
Symptoms of bladder outlet obstruction
•
Urgency
•
Frequency
•
Hesitancy
•
Poor flow
•
Dribbling
Change in urine volume
Polyuria
Means increased volume of urine as the capacity of the
bladder is limited, polyuria is associated with frequency
N.B : In healthy adults urine out put will approximate to the
fluid intake minus the insensible fluid losses through the
skin and respiratory tract[500-800 ml/day], average 2-3
liters/day
Causes
1-Diabetes mellitus (due to osmotic effect of glucose)
2-Chronic renal failure especially with chronic
tubulointertsitial fibrosis
3-Diabetes insipidus
4- Hypercalcaemia (due to impaired tubular concentrating
mechanism)
5- Hypokalemia (due to impaired tubular concentrating
mechanism)
6- Excessive fluid intake due to psychiatric disease.
Oliguria
Means diminished volume of urine <500 ml\day
Causes
1- Diminished intake of fluids
2- Hot weather
2- Pre-renal failure
3- Initial stage of acute renal failure
4- Terminal stage of chronic renal failure
Anuria
Means complete absence of urine formation so that no urine
reaches the bladder and the patient has no desire to micturate
Causes
•
•
lower urinary tract obstruction when bladder neck or urethral
obstruction causes urinary retention
Spinal injury through neurological damage
Change in urine colour
Haematuria
•
Means passage of red blood cells in urine
•
It can be
•
Macroscopic causing a reddish discoloration of the urine
•
Microscopic when excess red cells are detected in urinary
sediment
•
Causes
1- Prerenal e.g. Haemoragic diseases as purpura and over dose
of anticoagulants
2-Renal e.g. Stones, tumours, glomerulonephritis, and renal T.B
3-Ureter: stone and tumours
4- Bladder : cystitis, stone and tumours
5- Prostate : prostatitis, prostatic hypertrophy and tumours
6- Urethra: trauma, stricture, stone and tumours
It should be noted that
•
•
Terminal haematuria indicates a lesion in the urethra,
prostate , or bladder neck while total haematuria means the
lesion is higher up
Haematuria associative with renal colic is suggestive of
stone
•
Painless frank haematuria is suggestive of tumour
•
Microscopic haematuria is suggestive of a
parenchymatous lesion as glomerulonephritis
• Differential diagnosis of haematuria (causes of reddish
urine)
•
Contamination of urine by menstrual blood
•
Free hemoglobin due to intravascular hemolysis
•
Free myoglobin in rhabdomyolysis
•
Drug therapy : rifampcin
Change in urine contents
Proteinuria
 Proteinuria is usually asymptomatic
unless gross > 2-3 g/day
 Severe proteinuria may produce
frothy urine
 Lowering the plasma albumin
concentration, oncotic pressure
 Generalized oedema and nephrotic syndrome
Causes of proteinuria
1. Renal disease
•
•
•
Glomerulonephritis
Diabetes mellitus
Lupus nephritis
•
Non renal disease
•
Fever
•
•
Severe exertion
Heart failure
General symptoms of chronic kidney disease
General symptoms of renal disease
• Broadly non specific
• Occur in chronic kidney disease due to retention of
uremic toxins
• Nausea vomiting itching disturbed consciousness
• Fatigue and pallor secondary to anemia
• Bony aches and muscle weakness
• Shortness of breath (anemia, volume overload)
Uremic symptoms
Symptoms secondary to anemia
Symptoms secondary to bone disease
Symptoms secondary to volume overload
1. Lower limb swelling
2. Pleural effusion
3. Pulmonary edema
Investigations
Renal function tests
•
Serum creatinine
•
Blood urea
•
Serum electrolytes
•
Complete blood count
•
Creatinine clearance
•
Serum calcium and phosphorus
Urine analysis
Flat colorless hexagonal plates, which often aggregate
Urine analysis
Flat colorless hexagonal plates, which often aggregate
Stix test for blood protein sugar
Red cell cast
Cystine crystals
Flat colorless hexagonal plates which often aggregate
Microscopic examination
Radiologic assessment of UT
Plain X-ray Abdomen
Detection of calcification and radiopaque stones
Ureteric stone
bilateral staghorn stones
Right staghorn stone
Intravenous Pyelogram (IVP)
Hydronephrosis
Renal ultrasonography
No exposure to radiation and no dye is used
1. Assess renal dimensions
2. Exclude obstruction
3. Polycystic kidney Disease
Renal biopsy
Indications
•
Nephrotic syndrome
•
Nephritic syndrome
•
Acute renal failure
•
Proteinuria, haematuria
Normal glomerulus
Membranous nephropathy
Necrotizing GN
THE END
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
`