Adult urinary tract diagnosis and management, Urinary tract infection, Urology, recurrent uti

1. Adult Urinary Tract Infections-
Spectrum,Diagnosis and
Management.
Dr Sonu Kumar Plash.

2. Infections defined clinically by their presumed site of
origin.
• Cystitis describes a clinical syndrome of dysuria(burning micturition),
frequency,urgency, and occasionally suprapubic pain.
• Generally indicative of bacterial cystitis , but may also be associated with
infection of the urethra or vagina or noninfectious conditions such as
interstitial cystitis/ painful bladder syndrome,bladder carcinoma, or calculi.
• Acute pyelonephritis is a clinical syndrome of chills, fever, and flank pain
that is accompanied by bacteriuria and pyuria.
• The term should not be used if flank pain is absent.
• Chronic pyelonephritis describes a shrunken, fibrosed kidney,diagnosed
by morphologic, radiologic, or functional evidence of renal disease that
may be postinfectious but is frequently not associated with current (active)
UTI.eg-xgpn.

3. UTIs may also be described in terms of the anatomic or
functional status of the urinary tract and the health of the
host.
• Uncomplicated - an infection in a healthy patient with a structurally and
functionally normal urinary tract; this often specifically refers to the
absence of obstruction to any part of the urinary tract.
• Complicated infection is associated with factors that increase the chance
of acquiring bacteria and decrease the efficacy of therapy.
• The urinary tract is structurally or functionally abnormal, the host is
compromised, and/or the bacteria have increased virulence or
antimicrobial resistance.

5. UTIs may also be defined by their relationship
to other UTIs:
• A first or isolated infection is one that occurs in an individual who has never had
a UTI or has one remote infection from a previous UTI.
• Unresolved infection- has not responded to antimicrobial therapy and is
documented to be the same organism with a similar resistance profile.
• Recurrent infection-is one that occurs after documented, successful resolution of
an antecedent infection.(more than 2 inf in 6 month or 3 inf in 12 months)
• 2 different types of recurrent infection:
1. Reinfection describes a new event associated with reintroduction of bacteria into
the urinary tract from outside.
2. Bacterial persistence refers to a recurrent UTI caused by the same bacteria
reemerging from a focus within the urinary tract, such as an infectious stone or the
prostate.

6. Pathogenesis-Routes of infection.
1.Ascending route
• Most bacteria from bowel and skin reservoir via ascent through the urethra into
the bladder.
• Although reflux of urine is probably not required for ascending infections, edema
associated with cystitis may cause sufficient changes in the ureterovesical
junction to permit reflux.
2.Hematogenous route
• Uncommon, staphylococcus aureus bacteremia originating from oral sites.
3.Lymphatic route
• Severe bowel infection or retroperitoneal abscesses.

7. Urinary pathogens.
• E. coli -MC cause of UTI, 85% of community-acquired and
50% of hospital-acquired infections.
• Other gram-negative Enterobacteriaceae- including Proteus and
Klebsiella, and gram-positive Enterococcus faecalis and
Staphylococcus saprophyticus responsible for the rest of most
community-acquired infections.
• Nosocomial infections are caused by E. coli, Klebsiella,
Enterobacter, Citrobacter, Serratia, Pseudomonas aeruginosa,
Providencia, E. faecalis, and Staphylococcus epidermidis.

9. Events in UPEC pathogenesis.

10. Natural Defenses of the Urinary Tract
1. Periurethral and urethral region- lactobacillus,cons,corynebacterium and
streptococci form a barrier that protect against UPEC.
2. Urine- bacterial growth is inhibited by either very dilute urine or a high
osmolality when associated with low ph(acidic).
3. Uromodulin(tamm horsefall protein) -kidney derived mannosylated protein-
defensive role by saturating all the mannose binding sites of type 1 pili.
4. Bladder -toll like receptors-innate immune response.

11. Any alterations in host defence mechanisms can
cause UTI.
• Obstruction of urinary tract-stasis-bacterial overgrowth.
• VUR.
• DM(only in women).
• Renal papillary necrosis.
• HIV-5x risk of uti.
• Pregnancy.
• Spinal cord injury with high pressure bladders.
• Renal transplantation.
• Menopause-increased risk.

12. Evaluation.
• HISTORY

13. Physical examination
• Focus on the abdominal and pelvic regions.
• Suprapubic area examination-bladder distention may be palpated, often an
indicator of an elevated postvoid residual.
• Costovertebral-angle tenderness should be assessed, particularly if the
suspicion for pyelonephritis is high.
• Presence of vaginal discharge should be noted.
• In postmenopausal women- quality of the vaginal epithelium-vaginal
atrophy, pelvic organ prolapse.
• In men a DRE should be performed to assess the prostate.
• A focused neurologic exam on the pelvic area should be performed to
assess whether sensation is intact.

14. Diagnosis by Urine Testing
• Urine collection- diagnosis of UTI is dependent on a properly collected urine sample.
• Goal -reducing bacterial contamination during collection.
• Cleaning the meatus before giving a midstream voided sample.
• Women should be instructed to spread the labia, wash and cleanse the periurethral area
with soap.
• If a patient has an indwelling foley catheter and there is suspicion of a uti, the
catheter should be removed and a new catheter should be placed under sterile
conditions to obtain a sample.
• Samples should not be taken from an ostomy appliance; rather they should be obtained
via intubation of the stoma.
• For infants and young children- suprapubic aspiration of urine for culture is the “gold
standard.”

15. • Leukocyte esterase- indicative of pyuria, but not bacteria specifically.
• Nitrate reductase test- detect bacteria- All Enterobacteriaceae
produce nitrites, including E. coli, Klebsiella, Enterobacter, Proteus,
Citrobacter, Morganella, and Salmonella spp.
• Non–nitrite-producing bacteria include all gram positives and
Pseudomonads (e.g., Pseudomonas and Acinetobacter).

16. Urine Dipsticks
• In a patient who has symptoms strongly suggestive of a UTI, a positive
dipstick can be helpful in determining whether to initiate antibiotics.
• Positive nitrites or positive leukocyte esterase and blood on a
dipstick accurately diagnose a uti.
• Brand name-Urisign
• 50 strips for 500 rs.

17. Urine Analysis(URM)
• Automated urinalysis can reliably rule out a UTI and preclude the
need to order a urine culture.
• The strongest predictors of a UTI, in the correct clinical context,
include moderate bacteriuria, moderate pyuria, and nitrites.
• Moderate pyuria, defined as WBC count greater than 50, in
conjunction with symptoms suggestive of a UTI, justifies treatment
with antibiotics.
• If a culture is positive yet no pyuria is demonstrated on urinalysis,
consider obtaining a catheterized sample.
• Results of urinalyses are interpreted in conjunction with the clinical
presentation and eventually correlation with a urine culture.

18. Urine Culture- Gold standard.
• A colony count of at least 105 cfu/ml of urine is used to diagnose a
uti.
• In dysuric patients,significant bacteriuria is 102 cfu/ml of a known
pathogen.
• Urinary levels of antimicrobials are often several hundred times
greater than the serum levels.
• Inhibitory concentrations in urine are achieved after oral
administration of all commonly used antimicrobial agents, except for
the macrolides (erythromycin).

19. Imaging
• Not required in most cases of UTI.
• Clinical and laboratory findings are sufficient.
• A uti associated with possible urinary tract obstruction must be urgently
evaluated.

20. Imaging
• The 2nd reason for radiologic evaluation is to diagnose a focus of bacterial
persistence. When bacteriuria fails to resolve after appropriate
antimicrobial therapy or who have rapid recurrence of infection,
abnormalities that allow bacterial persistence should be sought.

21. Imaging
• USG KUB
• Useful in identifying hydronephrosis, pyonephrosis, and perirenal abscesses.
• A single radiograph for calculi could accompany ultrasonography.
• The sensitivity of ultrasound for demonstrating renal parenchymal abnormalities
in acute pyelonephritis is lower than that of ct and mri.
• CT/MRI
• Offer best anatomic detail.
• More sensitive than excretory urography or usg in the diagnosis of acute focal
bacterial nephritis, renal and perirenal abscesses, and radiolucent calculi.
• Improves the approach to surgical drainage and permits percutaneous
approaches.

22. VCUG
• For assessing VUR.
• In women with a history of febrile UTIs, known VUR as
a child, or recurrent pyelonephritis as an adult, a
voiding cystourethrogram (VCUG) should be
performed.
• VCUG should also be considered in patients with a
history of recurrent UTIs and hydronephrosis detected
on upper tract imaging.

23. Asymptomatic Bacteriuria.

26. Bladder Infections- Uncomplicated Cystitis.
• Most cases occur in women.
• Each year, approximately 10% of women report having had a UTI.
• >50% of all women have at least one infection in their lifetime.
• E. coli is the causative organism in 75% to 90% of cases of acute
cystitis in young women.
• S. saprophyticus, a commensal of the skin, 2nd MC cause of acute
cystitis in young women-10% to 20%.
• In men MC- E. coli and other Enterobacteriaceae.

28. Clinical presentation
• Frequency, urgency, painful urination, incomplete emptying,
suprapubic pain/pressure, low back pain, and hematuria.
• Cystitis is a superficial infection of the bladder mucosa, so
fever, chills, and other signs of dissemination are usually not
present.
• Foul-smelling or cloudy urine-not reliable indicators of uti.
• In the absence of above symptoms- should be encouraged to
hydrate vigorously and then reassess.

29. Management
• Nitrofurantoin-(100 mg twice daily for 5 days) is an appropriate
choice for first-line therapy because of minimal resistance.
• TMP and TMP-SMX (DS twice daily for 3 days) are effective and
inexpensive agents for empirical therapy, resulting in bacteriologic
cure (i.e., eradication of the pathogen from the urine) within 7 days
after the start of treatment in approximately 94% of women.
• Fosfomycin trometamol (3 g in a single dose) is an appropriate choice
for therapy where it is available because of minimal resistance.

30. Management
• The fluoroquinolones are effective in 3-day regimens.
• High propensity for collateral damage (i.e., ecological adverse effects, such as
drug resistance) and should be reserved as antimicrobials of last resort for acute
cystitis.
• β-lactam agents (such as amoxicillin-clavulanate, cefdinir, cefaclor, and
cefpodoxime-proxetil) remain second-line treatment options for uncomplicated
cystitis and can be used in 3- to 7-day regimens.
• Duration of therapy-
• Three-day therapy is the preferred regimen for uncomplicated cystitis in women.
• Seven-day therapy is the preferred regimen for cystitis in men.

32. Follow-up
• 90% of women are asymptomatic within 72 hours after
initiating antimicrobial therapy.
• A follow-up visit or culture is not required in women who are
asymptomatic after therapy.
• Further urologic evaluation is unnecessary in women who
respond to therapy.
• UTIs in most men should be considered complicated until
proven otherwise.

33. Recurrent Urinary Tract Infections
• Defined as 2 UTIs in a 6-month period or 3 or more UTIs in a 12-
month period.
• Secondary to either bacterial persistence within the urinary tract or,
more commonly,reinfection.
• Obtaining a thorough medical history is imperative.
• Ask about the prior number of infections and their frequency, culture
results, associated symptoms, and identifiable triggers or risk factors.
• Prior treatment strategies and patient response should be carefully
investigated.

35. Work-up
• Urinalysis and urine culture
• Postvoid residual and uroflow measurement.
• Imaging and cystoscopic evaluation are not warranted in all
women with recurrent utis, however in women with risk
factors for a complicated uti the evaluation should include
imaging and cystoscopy.
• Preferred imaging-USG KUB with possible plain radiograph of
the abdomen.

37. Management- Behavioral modifications.
• Hydration(3 l) is recommended to augment innate immunity by
sloughing of urothelial cells and flushing of adherent bacteria.
• Frequent voiding(every 4 hourly) helps to continually empty the
bladder.
• Emptying the bladder immediately after intercourse should help
minimize the likelihood that the transient bacteriuria will
progress to clinical symptomatology of a uti.
• Wipe front to back.
• Avoid non breathable undergarments.

38. Management of recurrent uti
• Low dose continuous prophylaxis-
• Regimens include nitrofurantoin 50 mg or 100 mg once daily.
• Fosfomycin trometamol 3 g every ten days.
• Trimethoprim 100 mg once daily.
• During pregnancy- cephalexin 125 mg or 250 mg or cefaclor 250 mg once
daily.
• Nitrofurantoin remains a popular choice for prophylaxis because it
concentrates in urine, is efficacious against many uropathogens, and
does not promote widespread resistance.
• No consensus about the optimal duration of continuous antimicrobial
prophylaxis, with studies reporting treatment duration of 3 to 12 months.

39. Management of recurrent uti.
• Self-start therapy -In patients with good compliance, self-
diagnosis and self-treatment with a short course regimen of an
antimicrobial agent should be considered.
• The choice of antimicrobials is the same as for sporadic acute
uncomplicated UTI.
• Postcoital antibiotic- acceptable strategy in patients with a
clear-cut causal relationship between intercourse and onset of UTIs
when other management options have not been effective-
Nitrofurantoin 50 mg,cephalexin 500mg,TMP-SMX 40/200mg,
fluoroquinolone as a single dose.

40. Non antibiotic management of recurrent uti.
• Cranberry-active ingredient -polyphenol type A proanthocyanidin (PAC)-
prevents the P fimbriae of E. coli from adhering to uroepithelial cells.
• 36 mg of PAC equivalents/day has been shown to be effective, but 72 mg
may be even more effective.
• Indian brands like Cranpac-D- 1.185 gram tablets.consisting of D-Mannose
600 mg and cranberry extract 300 mg out of which 25% is PAC.
• Because the anti-adhesion effect is not long acting,the product should be taken
twice a day.
• D-mannose- is a simple sugar that has shown some promise recently in
preventing bacterial adhesion to the urothelium.
• ESTROGEN- vaginal estrogen is effective in preventing recurrent UTIs in
postmenopausal women.
• The beneficial effect from vaginal estrogen use can take at least 12 weeks
to manifest.
• Estriol vaginal cream- 0.5 mg hs for 2 weeks ,then twice weekly for 8
months.

41. Non antibiotic management of recurrent uti.
• Methanamine- 70% to 90% renally excreted and are converted to
ammonia and formaldehyde in an acidic environment (pH < 6).
Formaldehyde is either bactericidal or bacteriostatic in urine depending on
its concentration.
• To achieve acidification of the urine when these oral tablets are taken, high
doses of ascorbic acid (vitamin C) (1–4 g) can be ingested in conjunction
with the methenamine (recommended dose is 1 g twice daily).
• Two formulations of methenamine are FDA approved, methenamine
hippurate and methenamine mandelate.
• Not Available in india.

42. Immunoactive prophylaxis:-
• The oral immunostimulant OM-89 (Uro-Vaxum) is an extract
that contains 18 serotypes of heat-killed uropathogenic E. coli.
The different serotypes increase neutrophils and macrophage
phagocytosis, thereby stimulating the host immune system to
target uropathogenic E. coli.
• Several meta-analyses and systematic reviews based on nine RCTs
showed that oral immunotherapy with OM-89 is an effective and safe
method for the prevention of rUTIs compared to placebo at short-
term follow-up (< six months).
• Not available in india. oral capsules.
• There is need for future high-quality studies with longer follow-
up before endorsement of OM-89 for use in prophylaxis.

43. • A vaginal vaccine (urovac)- works via stimulating iga and igg in the urinary
tract and subsequently decreasing potential colonization of uropathogens
has also been studied.
• Contains 10 heat-killed uropathogenic bacterial species, including six
serotypes of uropathogenic e. Coli, proteus vulgaris, K. Pneumoniae,
morganella morganii, and E. Faecalis.
• UROMUNE(MV 140)-Sublingual bacterial vaccine.by immunotek(spain).
• Prophylaxis with probiotics (Lactobacillus spp.).
• Of the ten systematic reviews seven concluded that prophylaxis with
vaginal probiotics has a beneficial clinical impact for the prevention of rUI.
• The available data was of too low-quality to allow the panel to make
recommendations on the route of admission, optimal dosage, and
treatment duration for probiotic prophylaxis.

44. Complicated Urinary Tract Infections.

45. • The clinical spectrum ranges from mild cystitis to life-threatening kidney
infections and urosepsis
• For patients with mild to moderate illness-OPD treatment with oral
fluoroquinolones for 10 to 14 days.
• For patients requiring hospitalization, IV antimicrobials based on culture
continued for 10 to 14 days.
• Correct underlying urinary tract abnormalities, such as obstruction, and treat
host factors that exacerbate the infection.
• Repeat urine cultures should be performed if the patient fails to respond to
therapy.

46. Emphysematous Cystitis
• Rare, life threatening.
• Mortality rate-7%.
• Early medical therapy important.
• MC in elderly women (60–70 years of age) with poorly controlled diabetes.
• Additional risk factors-any condition that may predispose to incomplete emptying and lower
urinary stasis, such as neurogenic bladder and bladder outlet obstruction.
• Causative organism- E. coli (60%) and K. pneumoniae (10%–20%).
• Clinical features-
• MC symptom- Abdominal pain (80%).
• Gross hematuria (60%).
• Obstructive urinary symptoms (10%).
• Fever(30-50%).
• Asymptomatic-7%.

47. Imaging
• Plain x-ray- curvilinear areas of increased radiolucency delineating the bladder wall and separate from
the rectal gas posteriorly described as a cobblestoned or “beaded necklace” appearance, reflecting the
irregular submucosal blebs.
• CT pelvis- show air pocketed diffusely within the bladder wall, and possibly intraluminally, it is
necessary to make the diagnosis and exclude other sources of pelvic air such as a fistula, trauma,
or gangrene of adjacent structures.

48. Management
• The majority (90%) of these patients are treated with
medical therapy alone-IV antibiotics, bladder drainage,
and treatment of comorbid conditions such as poorly
controlled diabetes.
• Surgical intervention is rare-debridement, partial
cystectomy, and total cystectomy in advanced cases.

49. Kidney Infections- Acute Pyelonephritis
• Defined as inflammation of the kidney and renal pelvis, the
diagnosis is clinical.
• Clinical Presentation-
• Abrupt onset of chills, fever (100.3°F or greater)
• Unilateral or bilateral flank or costovertebral angle pain and/or
tenderness.
• Sometimes accompanied by dysuria, increased urinary frequency, and
urgency, but in many cases lower urinary symptoms are not present.
• On physical examination, there often is tenderness to deep palpation
in the costovertebral angle.

50. Diagnosis-
• Cbc- leukocytosis with a predominance of neutrophils.
• Urinalysis- numerous wbc, often in clumps, and bacterial rods or
chains of cocci.
• Urine cultures are positive, but about 20% negative.
• E. Coli-80% of cases.
• Except for E. Faecalis, S. Epidermidis, and S. Aureus, gram-positive
bacteria rarely cause pyelonephritis.
• Blood cultures- positive in about 25% of cases of uncomplicated
pyelonephritis in women, and replicate the urine culture,do not
influence decisions regarding therapy.
• Therefore blood cultures should not be routinely obtained for the
evaluation of uncomplicated pyelonephritis in women. However, they
should be performed in men and women with systemic toxicity or in
those requiring hospitalization or with risk factors such as
pregnancy.

51. Imaging:-
• USG KUB- focal parenchymal swelling and regions of
increased or decreased echogenicity.
• CT /MRI- show focal swelling and diminished and
inhomogeneous parenchymal contrast enhancement.
• Radiographic changes usually resolve; therefore future renal
imaging will show a normal appearing kidney.

53. Management
• Initial management.

55. Subsequent management.
• If blood cultures are negative, 2- to 3-day parenteral therapy is
sufficient.
• After parenteral therapy, an appropriate oral antimicrobial drug
(fluoroquinolone, TMP, TMP-SMX, or amoxicillin or amoxicillin/
clavulanic acid for gram-positive organisms) should be continued in
full dosage for an additional 10 to 14 days.
•Unfavorable Response to Therapy.
• An immediate reevaluation is mandatory.
• Urine and blood cultures must be repeated.
• In patients with fever lasting longer than 72 hours, CT is most
helpful for ruling out obstruction and identifying renal and
perirenal infections.
• Any substantial obstruction must be relieved expediently by
ureteral stent or percutaneous nephrostomy tube placement.

56. Emphysematous Pyelonephritis
• Urologic emergency.
• Characterized by an acute necrotizing parenchymal and perirenal infection.
• Caused by gas-forming uro-pathogens.
• Risk factors-
• 1.Diabetes.
• 2.Urinary tract obstruction associated with urinary calculi or papillary necrosis
and significant renal functional impairment.
• High tissue glucose levels provide the substrate for microorganisms such as E.coli,
produce carbon dioxide by the fermentation of sugar.
• The overall mortality rate has been reported to be between 19% and 43%.

57. Clinical presentation.
• Nearly all documented cases have occurred in adults.
• Women> men.
• Classic triad- fever, vomiting, and flank pain.
• Pneumaturia is absent unless the infection involves the
collecting system.
• Urine cultures are invariably positive.
• E. Coli is MC causative organism. Others-klebsiella and proteus
spp. Are less common.

58. Imaging
• The diagnosis is established radiographically.
• Xray kub- mottled gas shadows over the involved kidney.
• USG KUB- strong focal echoes suggesting the presence of
intraparenchymal gas.
• CT - imaging of choice in defining the extent of the emphysematous
process and guiding management.
• Obstruction is demonstrated in approximately 25% of the cases.
• A nuclear renal scan should be performed to assess the degree of
renal function impairment in the involved kidney and the status of the
contralateral kidney.

60. Wan et al classification.(CT based).
• 1.Dry type- An absence of fluid in CT images or the presence
of streaky or mottled gas appears to be associated with rapid
destruction of renal parenchyma and a 50% to 60% mortality
rate.
• Bad prognosis.
• 2.Wet type- The presence of renal or perirenal fluid,and the
absence of streaky or mottled gas patterns are associated with
a less than 20% mortality rate.
• Good prognosis.

61. Huang et al classification.
• I-Gas confined to renal pelvis(emphysematous pyelitis).
• II-Gas confined to renal parenchyma.
• III A-Gas confined to perinephric space.
• III B-Gas confined to paranephric space.
• IV –Gas in bilateral kidneys or solitary functioning kidney.

62. Management.
• Most patients are septic, and fluid resuscitation, glucose and
electrolyte management, and broad-spectrum antimicrobial
therapy are essential.
• Ureteral obstruction, if present- a percutaneous nephrostomy
tube or a stent should be inserted.
• The overall mortality rate has decreased with advancements in
medicine, and definitive management is by percutaneous
drainage, except in cases of extensive diffuse gas with renal
destruction; in this latter scenario, nephrectomy is advised.

63. Renal Abscess/Carbuncle.
• Collection of purulent material confined to the renal parenchyma.
• Historically- 80% cause was hematogenous seeding by staphylococci.
• Since 1970-Gram negative organisms, No gender predominance, and
no laterality.
• Mc organism include E. coli, klebsiella, proteus, and pseudomonas
spp.
• Two-thirds of gram-negative abscesses in adults are associated with
renal calculi or damaged kidneys.
• Reflux is frequently associated with renal abscesses.

64. Clinical presentation.
• Fever, chills, abdominal or flank pain, and occasionally weight loss and malaise.
• Symptoms of cystitis may occur.
• A thorough history may reveal a gram-positive source of infection 1 to 8 weeks before the onset of urinary
tract symptoms or symptoms consistent with UTI or pyelonephritis in the weeks prior.
• Predisposing factors
1. Diabetes mellitus
2. HIV
3. Steroid use
4. IV drug abuse
5. Liver disease
6. Complicated uti asso with stasis, calculi, neurogenic bladder.
7. Pregnancy
8. Increased length of hospitalization

65. Diagnosis
• CBC- marked leukocytosis.
• Pyuria and bacteriuria may not be evident unless the abscess communicates with the
collecting system.
• Positive urine cultures present in roughly 30% of patients.
• USG KUB- quickest and least expensive method to demonstrate a renal abscess.
• An echo-free or low-echodensity space-occupying lesion with increased transmission is
found.
• CT- appears to be the diagnostic procedure of choice for renal abscesses.
• On CT, abscesses are characteristically well defined before and after contrast agent
enhancement. The findings depend in part on the age and severity of the abscess.
• The ring sign is caused by the increased vascularity of the abscess wall.

68. Management
• Immediately started on IV antibiotic therapy.
• Iv third-generation cephalosporins, antipseudomonal penicillins, or
aminoglycosides until specific therapy can be instituted.
• Serial examinations with ultrasonography or CT to be done until the abscess
resolves.
• Size of the abscess typically dictates management.
Abscesses 3 cm or less can be managed with antibiotics alone.
3-5 cm and clinically stable pt- antimicrobial therapy.
>5 cm-percutaneous drainage- Abscesses of this size require multiple drains,
multiple drain manipulations, or eventual surgical washout.

69. Infected Hydronephrosis and Pyonephrosis.
• Infected hydronephrosis is bacterial infection in a hydronephrotic kidney.
• Pyonephrosis refers to infected hydronephrosis associated with suppurative
destruction of the parenchyma of the kidney, in which there is total or nearly
total loss of renal function.
• Clinical features-
• Usually very ill, with high grade fever, chills, flank pain, and tenderness.
• A previous history of urinary tract calculi, infection, or surgery is common.
• Bacteriuria may not be present if the ureter is completely obstructed.
• Radiology-
• USG kub-internal echoes within dependent portion of dilated pcs.
• Ct is non specific, may show stranding of perirenal fat.

71. Management
• Appropriate antimicrobial drugs and drainage of the
infected pelvis.
• A ureteral catheter can be passed to drain the kidney,
but if the obstruction prevents this, a percutaneous
nephrostomy tube should be placed.

72. Perinephric Abscess.
• Extends beyond the renal capsule but is contained by gerota fascia.
Causes-
• Rupture of an acute cortical abscess into the perinephric space.
• Extravasated infected urine from obstruction.
• Patients with pyonephrosis, with calculus in the kidney.
• 1/3rd pts have Diabetes mellitus.
• 1/3rd cases caused by hematogenous spread, usually from sites of
skin infection.
• Infected pararenal haematoma.
• Perinephric or psoas abscess may be the result of bowel perforation,
Crohn disease, or spread of osteomyelitis from the thoracolumbar spine.

73. • When a perinephric infection ruptures through the Gerota fascia
into the pararenal space, the abscess becomes paranephric.
• Paranephric abscesses may also result from infectious
disorders of the bowel, pancreas, or pleural cavity.
• E. coli, Proteus, and S.aureus account for most infections.

74. Clinical presentation.
• Onset of symptoms is typically insidious.
• Symptoms are present for more than 5 days in most patients with
perinephric abscess compared with only about 10% of patients with
pyelonephritis.
• Pyelonephritis usually responds within 4 to 5 days of appropriate
antimicrobial therapy; perinephric abscess does not. Thus
perinephric abscess should be suspected in a patient with UTI and
abdominal or flank mass or persistent fever after 4 days of
antimicrobial therapy.
• The clinical presentation may be similar to that of pyelonephritis;
• However, more than one-third of patients may be afebrile.
• An abdominal or flank mass can be felt in about half of the cases;
• Costovertebral angle tenderness is typically present.

75. Diagnosis.
• Laboratory features- leukocytosis, elevated levels of serum creatinine, and
pyuria in more than 75% of cases.
• Results of urine cultures predicted perinephric abscess isolates in only
37% of cases
• Blood culture, particularly with multiple organisms, was often indicative of
perinephric abscess but identified all organisms in only 42%.
• Therefore caution should be exercised when choosing therapy based
on the results of urine and blood cultures because data may
sometimes be inadequate.
• CT is particularly valuable for demonstrating the primary abscess.
• Improved imaging techniques have decreased the mortality rate of 40% to
50% in early series to roughly 12%.

77. Management
• Antimicrobial agents should be immediately started upon
diagnosis of perinephric abscess
• Unlike in renal abscesses, early drainage of abscesses >3 cm
is recommended.
• Once the perinephric abscess has been drained, the
underlying problem must be addressed.

78. Infectious Granulomatous Nephritis-
Xanthogranulomatous Pyelonephritis(XGP).
• Rare- found in only about 0.6% to 1.4% of patients with renal inflammation who are
evaluated pathologically.
• Severe,chronic renal infection typically resulting in diffuse renal destruction.
• Most cases are unilateral.
• It begins within the pelvis and calyces and subsequently extends into and destroys
renal parenchymal and adjacent tissues.
• Imitates almost every other inflammatory disease of the kidney, as well as renal cell
carcinoma, on radiographic examination.
• The microscopic appearance of xgp has been confused with clear cell adenocarcinoma of
the kidney on frozen section and has led to radical nephrectomy.
• XGP has been associated with RCC, papillary transitional cell carcinoma of the
pelvis or bladder, and infiltrating squamous cell carcinoma of the pelvis.

79. Pathogenesis
• The primary factors involved in the pathogenesis of XGP are nephrolithiasis,
obstruction, and infection.
• Nephrolithiasis noted in 83%.
• Approximately half of the renal stones are staghorn type.
• Primary obstruction followed by infection with E. coli can lead to tissue destruction and
collections of lipid material by macrophages (xanthoma cells).
• Bacteria appear to be of low virulence because spontaneous bacteremia has rarely been
described.
• Pathology- kidney is usually massively enlarged and has a normal contour.
• 2 types:-
1. Diffuse 80%.
2. Segmental- 20% - only the parenchyma surrounding one or more calyces or one pole of
a duplicated collecting system is involved.

80. Clinical presentation.
• XGP should be suspected in patients with UTIs and a unilateral enlarged nonfunctioning or poorly
functioning kidney with a stone or a mass lesion indistinguishable from malignant tumor.
• Flank pain (69%),
• Fever and chills (69%)
• persistent bacteriuria (46%)
• Flank mass-62%
• Previous calculi-35%.
• Diabetes-Risk factor.
• Medical history often positive for UTIs and urologic instrumentation.
• Peak Incidence- 5th to 7th decade.
• Women>men
• No side predilection.

81. Bacteriology and Diagnosis.
• Mc organism- Proteus,2nd E.coli.
• Urine analysis-Pus cells and albumin.
• XGP is almost always unilateral, therefore azotemia or frank renal failure is
uncommon.
• CT is probably the most useful radiologic technique.
• 50 to 80% show the classic triad of unilateral renal enlargement with little
or no function and a large calculus in the renal pelvis.

82. Large right staghorn calculus, with ultrasound demonstrating dilated fluid filled spaces, without
hydronephrosis. CT- an enlarged right kidney, with a bear's paw appearance of xanthogranulomatous
pyelonephritis (XPN) with a small perinephric collection.

83. Management.
• With CT, the diagnosis of XGP is made preoperatively nearly 90% of the time.
• Antimicrobial therapy may be necessary to stabilize the patient preoperatively,
and, occasionally, long-term antimicrobial therapy will eradicate the infection
and restore renal function.
• Because the renal abnormality may be diagnosed preoperatively as a renal tumor
and/or is diffuse, nephrectomy is usually performed.
• If localized XGP is diagnosed preoperatively or at exploration, it is amenable to
partial nephrectomy.
• Benefits of laparoscopic surgery do not extend to the treatment of this disease.
• Although feasible, removal of an XGP kidney is difficult, and high conversion rates
were seen across multiple studies.

84. Bacteriuria in Pregnancy.
• The prevalence varies from 4% to 7%, and the incidence of acute clinical
pyelonephritis ranges from 25% to 35% in untreated bacteriuric women.
• Screening with urine culture is recommended at the initial visit by the American
College of Obstetricians and Gynecologists (ACOG).
• Spontaneous resolution of bacteriuria unlikely unless it is treated.
• Pyelonephritis develops in 1% to 4% of all pregnant women and in 15% to 45% of
pregnant women with untreated bacteriuria.
• Of the women who develop pyelonephritis during pregnancy, 60% to 75% acquire
it during the third trimester when hydronephrosis and stasis in the urinary tract
are most pronounced.
• Treatment of screening bacteriuria of pregnancy decreases the incidence of
acute pyelonephritis during pregnancy from a range of 13.5% to 65% to a range
of 0 to 5.3%.

85. Pathogenesis.
• Anatomic and physiologic changes during pregnancy.
• Renal length increases approximately 1 cm during normal pregnancy. Result of increased
renal vascular and interstitial volume.
• Smooth muscle atony of the collecting system and bladder.
• Muscle-relaxing effects of increased progesterone during pregnancy and to mechanical
obstruction of the ureters by the enlarging uterus at the pelvic brim.
• Augmented renal function
• GFR increases by 30% to 50%, and urinary protein excretion increases.
• Values considered normal in non-pregnant women may represent renal insufficiency
during pregnancy.

86. Laboratory diagnosis
• An initial screening culture should be performed in all pregnant
women during the first trimester.
• The us preventive services task force recommends screening for
asymptomatic bacteriuria with urine culture in pregnant women at 12
to 16 weeks gestation or at the first prenatal visit, if later.
• If the culture shows no growth, repeat cultures are generally
unnecessary because patients who have no growth in their urine
early in their pregnancy are unlikely to develop bacteriuria later.

87. Management
• Aminopenicillins and cephalosporins are considered safe and generally
effective throughout pregnancy.
• In patients with penicillin allergy, nitrofurantoin is a reasonable alternative.
• It may be used safely during the first two trimesters in patients without
glucose-6-phosphate dehydrogenase deficiency.
• Nitrofurantoin is often used because fluoroquinolones and TMP-SMX are
contraindicated in pregnancy.
• If nitrofurantoin is used, however, this is discontinued at 35 weeks of gestation
because of an increased risk of hemolytic anemia in the neonate.
• If a pregnant woman has a single episode of pyelonephritis or two episodes of
cystitis, daily suppression with either nitrofurantoin or cephalexin should be
considered until delivery.
• It is prudent to prescribe a full 3- to 7-day course of therapy in pregnant women.

89. Catheter associated urinary tract infection.
• CDC define a CAUTI as a UTI after placement of an indwelling urinary catheter for
> 2 days.
• Criteria-must have one symptom of a UTI (suprapubic tenderness, CVA
tenderness, urinary frequency/urgency/dysuria, or fever >100.4°F) and a urine
culture with a single organism more than 100,000 CFU/mL.
• MC hospital-acquired infection.
• Incidence- approximately 10% per day of catheterization.
• Sterile and clean intermittent catheterization has been associated with rates of
bacteriuria ranging from 1% to 3% per catheterization.

90. CAUTI.
• The most important risk factors associated with increased likelihood
of developing catheter- associated bacteriuria are duration of
catheterization, female gender, absence of systemic antimicrobial
agents, and catheter-care violations.
• Most patients with catheter-associated bacteriuria are asymptomatic.
Mayo clinic protocol(bundled 6-c cauti approach):
1. Consider (appropriate placement and daily need for indwelling catheter),
2. Connect.
3. Clean (catheter care).
4. Closed (maintain closed system).
5. Call (irrigation when necessary).
6. Culture (only for indication).

91. Pathogenesis
• Bacteria can be introduced at the time of initial catheter Placement.
• Subsequently, the bacteria most commonly gain access via a
periurethral or intraluminal Route.
• Bacteria may also enter the drainage bag and follow the intraluminal
route to the bladder.
• E. coli is still the most common organism isolated, but Pseudomonas,
Proteus, and Enterococcus spp. are prevalent.
• In patients with long-term catheterization (more than 30 days), the
bacteriuria is usually polymicrobial, and the presence of four or five
pathogens is not uncommon.

92. Laboratory Diagnosis
• Significant bacteriuria in patients with catheters is present
when greater than 100 CFU/mL is present.
• Pyuria is not a discriminate indicator of infection in this
population.

93. Management
• Careful aseptic insertion of the catheter and maintenance of a closed dependent
drainage system are essential to minimize development of bacteriuria.
• The catheter-meatal junction should be cleaned daily with water, but antimicrobial
agents should be avoided because they lead to colonization with resistant pathogens
such as Pseudomonas.
• Incorporation of silver oxide or silver alloy into the catheter and hydrogen peroxide into
the drainage bag has been reported to decrease the incidence of bacteriuria in some
studies.
• Patients with indwelling catheters should be treated only if they become symptomatic
(e.g., febrile). Urine cultures should be performed before initiating antimicrobial
therapy.
• Antimicrobial therapy should be continued for 2 to 3 days and a post therapy culture
should be done 7 to 10 days later.

94. Antimicrobial Formulary