Editing Urinary Tract Infections (section)

==== Acute Pyelonephritis ====

===== Pathogens =====
* '''E. coli (80% of cases)''' constitutes a unique subgroup that possesses special virulence factors
* More resistant species, such as Proteus, Klebsiella, Pseudomonas, Serratia, Enterobacter, or Citrobacter, should be suspected in patients who have recurrent UTIs, are hospitalized, have indwelling catheters, or have had recent urinary tract instrumentation.
* Except for E. faecalis, S. epidermidis, and S. aureus, gram-positive bacteria rarely cause pyelonephritis.

====== Differential Diagnoses ======

# '''<span style="color:#ff0000">Acute appendicitis'''
# '''<span style="color:#ff0000">Diverticulitis'''
# '''<span style="color:#ff0000">Pancreatitis'''

* '''Can cause a similar degree of pain, but the location of the pain often is different'''

===== Diagnosis and Evaluation =====

====== History and Physical Exam ======
* The clinical spectrum ranges from gram-negative sepsis to cystitis with mild flank pain.
* '''<span style="color:#ff0000">History'''
**'''<span style="color:#ff0000">Signs and Symptoms'''
***'''<span style="color:#ff0000">Upper tract signs (3):'''
***#'''<span style="color:#ff0000">Abrupt onset of chills'''
***#'''<span style="color:#ff0000">Fever'''
***#'''<span style="color:#ff0000">Unilateral or bilateral flank or costovertebral angle pain and/or tenderness'''
***'''<span style="color:#ff0000">Often accompanied by LUTS such as (3):'''
***#'''<span style="color:#ff0000">Dysuria'''
***#'''<span style="color:#ff0000">Increased urinary frequency'''
***#'''<span style="color:#ff0000">Urgency'''
* '''<span style="color:#ff0000">Physical Exam'''
** '''<span style="color:#ff0000">Tenderness to deep palpation in the costovertebral angle'''

====== Labs ======
* '''<span style="color:#ff0000">CBC'''
** May have leukocytosis with a predominance of neutrophils.
* '''<span style="color:#ff0000">Urinalysis'''
** Usually reveals numerous WBCs, often in clumps, and bacterial rods or chains of cocci.
** '''The presence of large amounts of granular or leukocyte casts in the urinary sediment is suggestive of acute pyelonephritis.'''
* '''<span style="color:#ff0000">Urine cultures'''
** '''Usually positive'''
*** '''≈20% of patients have''' urine cultures with < 105 cfu/mL and therefore '''negative results on Gram staining of the urine'''
* '''<span style="color:#ff0000">Blood cultures'''
** '''<span style="color:#ff0000">Should not be routinely obtained for the evaluation of uncomplicated pyelonephritis in females.'''
*** '''Positive in ≈25% of cases of uncomplicated pyelonephritis in females and the majority replicate the urine culture and do not influence decisions regarding therapy.'''
** '''Should be performed in males and females with systemic toxicity or in those requiring hospitalization or with risk factors such as pregnancy'''
'''Imaging'''
* '''In patients with presumed uncomplicated pyelonephritis who will be managed as outpatients, initial radiologic evaluation can usually be deferred.'''
** However, if there is any reason to suspect a problem or if the patient will not have reasonable access to imaging if there should be no change in condition, renal US can rule out stones or obstruction.
* '''In patients with known or suspected complicated pyelonephritis, CT provides excellent assessment of the status of the urinary tract and the severity and extent of the infection.'''
*'''Renal US and CT are commonly used to evaluate patients initially for complicated UTIs or factors or to reevaluate patients who do not respond after 72 hours of therapy'''

===== Management =====
* '''Any substantial obstruction must be relieved expediently by the safest and simplest means.'''
**An obstructed kidney has difficulty concentrating and excreting antimicrobial agents.
*'''Antibiotics'''
**'''Oral'''
***'''Options[https://www.nice.org.uk/guidance/ng111/documents/draft-guideline-2 §]'''
****Amoxicillin / Clavulanic acid 625mg PO TID x 7 days
*****If a gram-positive organism is suspected, amoxicillin or amoxicillin/clavulanic acid is recommended
****Ciprofloxacin 500mg PO BID x 7 days
****Levofloxacin 500mg PO daily x 7 days
***Many physicians administer a single parenteral dose of an antimicrobial agent (ceftriaxone, gentamicin, or a fluoroquinolone) before initiating oral therapy.
**'''IV'''
***'''Options§'''
****Ceftriaxone 1-2g IV q24h
****Ciprofloxacin 400mg IV TID
****Gentamicin 5-7mg/kg q24h
*** For patients sufficiently ill to require hospitalization (high fever, high WBC count, vomiting, dehydration, evidence of sepsis), has complicated pyelonephritis, or fails to improve during the initial outpatient treatment period
*** If gram-positive cocci are causative, ampicillin/sulbactam with or without an aminoglycoside is recommended.
*'''Follow-up'''
**'''Repeat urine cultures should be performed after 5-7 days of therapy and 10-14 days after discontinuing antimicrobial therapy to ensure that the urinary tract remains free of infections.'''
***10-30% of individuals with acute pyelonephritis relapse after a 14-day course of therapy.
***Patients who relapse usually are cured by a second 14-day course of therapy, but occasionally a 6-week course is necessary