#urinary track infections ,acute, chronic pyelonephritis ,cystitis, etiology,

1. URINARY TRACK INFECTIONS

2. CONTENTS
 Introduction
 Historical aspects of inflammation
 Causes of inflammation
 Types of inflammation
 Acute & chronic inflammation
 Pathophysiology of acute inflammation
 Chemical mediators of inflammation
 Methods
 Conclusions
 References 2

3. introduction
 UTI is the infection in any part of the urinary
system.
 More common in women.
 Infection of upper urinary tract – kidney
infection (pyelonephritis).
 Infection of lower urinary tract – bladder
infection (cystitis).
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4. Acute pyelonephritis
 It is an acute suppurative inflammation caused by pyogenic bacteria.
 ETIOPATHOGENESIS
 It is the infection of lower urinary tract.
 The most common pathogenic organism in urinary tract infection (UTI)
is Escherichia coli (in 90% of cases), followed by Enterobacter,
Klebsiella, Pseudomonas and Proteus.
 The bacteria gain entry into the urinary tract, and then into the kidney
by one of the two routes:
 Ascending infection
 Haematogenous infection
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5. 1. Ascending infection:
 Most common route of infection.
 Pathogenic organisms are inhabitants of the colon and may cause faecal
contamination of the urethral orifice, especially in females in
reproductive age group.
 Females (shorter urethra) are liable to faecal contamination, hormonal
influences facilitating bacterial adherence to the mucosa, absence of
prostatic secretions which have antibacterial properties, and urethral
trauma during sexual intercourse (honeymoon pyelitis).
 Susceptibility is increased in patients with diabetes mellitus, pregnancy,
urinary tract obstruction.
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6.  Bacteria multiply in the urinary
bladder and produce asymptomatic
bacteriuria found in many of these
cases.
 After having caused urethritis and
cystitis, the bacteria in susceptible
cases ascend further up into the
ureters against the flow of urine,
extend into the renal pelvis and then
the renal cortex.
 The role of vesico-ureteral reflux is
not a significant factor in the
pathogenesis of acute
pyelonephritis as it is in chronic
pyelonephritis.
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Pathogenesis of reflux nephropathy

7. 1. Haematogenous infection:
 It is less often.
 Acute pyelonephritis may result from blood-borne spread of infection.
 This occurs more often in patients with obstructive lesions in the
urinary tract, and in debilitated or immunosuppressed patients.
CLINICAL FEATURES
 Acute onset with chills, fever, loin pain, lumbar tenderness, dysuria and
frequency of micturition.
 Urine will show abundance of bacteria, pus cells and pus cell casts in
the urinary sediment.
 Institution of specific antibiotics, after identification of bacteria by
culture followed by sensitivity test, eradicates the infection in majority
of patients.
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8. Chronic pyelonephritis
It is a chronic tubulointerstitial disease resulting from repeated attacks of
inflammation and scarring.
ETIOPATHOGENESIS
 Depending upon the etiology and pathogenesis, two types of chronic
pyelonephritis are described-
a)Reflux nephropathy
b)Obstructive pyelonephritis
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9. 1. Reflux nephropathy:
 Reflux of urine from the bladder into one or both the ureters during
micturition is the major cause of chronic pyelonephritis.
 Reflux results in increase in pressure in the renal pelvis so that the urine
is forced into renal tubules which is eventually followed by damage to
the kidney and scar formation.
 Vesicoureteric reflux is more common in patients with urinary tract
infection, whether symptomatic or asymptomatic, but reflux of sterile
urine can also cause renal damage.
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10. 2. Obstructive pyelonephritis:
 Obstruction to the outflow of urine at different levels predisposes the kidney to
infection
 Recurrent episodes of such obstruction and infection result in renal damage and
scarring.
 Rarely, recurrent attacks of acute pyelonephritis may cause renal damage and
scarring.
CLINICAL FEATURES
 Chronic pyelonephritis often has an insidious onset.
 The patients present with clinical picture of chronic renal failure or with
symptoms of hypertension.
 Sometimes, the patients may present with features of acute recurrent
pyelonephritis with fever, loin pain, lumbar tenderness, dysuria, pyouria,
bacteriuria and frequency of micturition.
Diagnosis is made by intravenous pyelography (IVP). Culture of the urine may
give positive results.
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12. cystitis
 Inflammation of the urinary bladder is called cystitis.
 Primary cystitis is rare since the normal bladder epithelium is quite
resistant to infection.
 Cystitis may occur by spread of infection from upper urinary tract as
seen following renal tuberculosis, or may spread from the urethra such
as in instrumentation.
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13. Etiology
 The most common pathogenic organism in UTI is E. coli, followed in
decreasing frequency by Enterobacter, Klebsiella, Pseudomonas and
Proteus.
 Infection with Candida albicans may occur in the bladder in
immunosuppressed patients.
 Parasitic infestations such as with Schistosoma haematobium is
common in the Middle-East countries, particularly in Egypt.
 Chlamydia and Mycoplasma may occasionally cause cystitis.
 Radiation, direct exposure to chemical irritant, foreign bodies and local
trauma may all initiate cystitis.
 It is more common in females than in males because of the shortness of
urethra which is liable to faecal contamination and due to mechanical
trauma during sexual intercourse.
 In males, prostatic obstruction is a frequent cause of cystitis.
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14. CLINICAL FEATURES
 Frequency (repeated urination),
 Dysuria (painful or burning micturition) and
 Low abdominal pain.
 Systemic manifestations of bacteraemia such as fever, chills and malaise
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15. TYPES OF CYSTITIS:
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S.
No.
Acute cystitis Chronic cystitis
1. The bladder mucosa is red, swollen
and haemorrhagic with suppurative
exudate or ulcers on the bladder
mucosa.
Repeated attacks of acute cystitis
lead to chronic cystitis.
The mucosal epithelium is
thickened, red and granular with
formation of polypoid masses.
Long-standing cases result in
thickened bladder wall and
shrunken cavity.