ACUTE PYELONEPHRITIS
Pyelonephritis, an upper UTI, is a bacterial infection of the renal pelvis, tubules, and interstitial tissue of one or both kidneys.
Causes involve either the upward spread of bacteria from the bladder or spread from systemic sources reaching the kidney
via the bloodstream. An incompetent ureterovesical valve or obstruction occurring in the urinary tract increases the
susceptibility of the kidneys to infection. Bladder tumors, strictures, benign prostatic hyperplasia, and urinary stones are
some potential causes of obstruction that can lead to infections. Pyelonephritis may be acute or chronic.
CAUSES/ RISK FACTORS
The main cause of acute pyelonephritis is gram-negative bacteria, the most common being Escherichia coli. Other gram-
negative bacteria that cause acute pyelonephritis include Proteus, Klebsiella, and Enterobacter. In most patients, the infecting
organism will come from their fecal flora. Bacteria can reach the kidneys in 2 ways: hematogenous spread and through
ascending infection from the lower urinary tract. Hematogenous spread is less common and usually occurs in patients with
ureteral obstructions or immunocompromised and debilitated patients. Most patients will get acute pyelonephritis through
ascending infection. Ascending infection happens through several steps. Bacteria will first attach to urethral mucosal
epithelial cells and will then travel to the bladder via the urethra either through either instrumentation or urinary tract
infections which occur more frequently in females. UTIs are more common in females than in males due to shorter urethras,
hormonal changes, and close distance to the anus. Urinary tract obstruction caused by something such as a kidney stone can
also lead to acute pyelonephritis. An outflow obstruction of urine can lead to incomplete emptying and urinary stasis which
causes bacteria to multiply without being flushed out. A less common cause of acute pyelonephritis is vesicoureteral reflux,
which is a congenital condition where urine flows backward from the bladder into the kidneys.
PATHOPHYSIOLOGY
DIAGNOSIS
Lab tests:
1. Urinalysis. For a urinalysis, you will collect a urine sample in a special container at a doctor’s office or at a lab. A health
care professional will look at the sample under a microscope for bacteria and white blood cells, which the body produces
to fight infection. Bacteria also can be found in the urine of healthy people, so a kidney infection is diagnosed based both
on your symptoms and a lab test.
2. Urine culture. A health care professional may culture your urine to find out what type of bacteria is causing the infection.
A health care professional can see how the bacteria have multiplied, usually in 1 to 3 days, and can then determine the
best treatment.
Imaging tests:
A health care professional may use imaging tests, such as a computed tomography (CT) scan, magnetic resonance imaging
(MRI), or ultrasound, to help diagnose a kidney infection. A technician performs these tests in an outpatient center or a
hospital. A technician may perform an ultrasound in a doctor’s office as well. A radiologist reads and reports on the images.
You don’t need anesthesia.
MEDICAL MANAGEMENT
Patients with acute uncomplicated pyelonephritis are most often treated on an outpatient basis if they are not exhibiting acute
symptoms of sepsis, dehydration, nausea, or vomiting. In addition, they must be responsible and reliable to ensure that all
medications will be taken as prescribed
For outpatients, a 2-week course of antibiotics is recommended; commonly prescribed agents include some of the same
medications prescribed for the treatment of UTIs.
Pregnant women may be hospitalized for 2 or 3 days of parenteral antibiotic therapy. Oral antibiotic agents may be
prescribed once the patient is afebrile and showing clinical improvement.
After the initial antibiotic regimen, the patient may need antibiotic therapy for up to 6 weeks if a relapse occurs. A
follow-up urine culture is obtained 2 weeks after completion of antibiotic therapy to document clearing of the infection.
Hydration with oral or parenteral fluids is essential in all patients with UTIs when there is adequate kidney function.
Pharmacologic Therapy
Drug Name Specific Action Contraindications Adverse effects Nursing
Responsibilities
Trimethoprim Inhibits Hypersensitivity to Seizures Monitor CBC
enzymes of sulfonamides, allergic myocarditis or with white cell
folic acid trimethoprim, pericarditis differential.
pathways. sulfonylureas, pseudo-membranous Watch for
thiazides, or loop colitis evidence of
diuretics crystalluria, toxic blood
Porphyria nephrosis with oliguria dyscrasias.
Marked renal or and anuria, renal Stay alert for
hepatic failure erythema
impairment megaloblastic anemia, multiforme.
Megaloblastic agranulocytosis, Report early
anemia caused by aplastic anemia, signs before
folate deficiency thrombocytopenia, condition can
Pregnancy at term leukopenia, hemolytic progress to
or when premature anemia Stevens-Johnson
birth is possible allergic pneumonitis, syndrome.
Infants younger pulmonary infiltrates, Monitor liver
than 2 months fibrosing alveolitis function tests
(except in P. and assess for
jiroveci evidence of
pneumonia hepatitis.
prophylaxis) Check kidney
function tests
weekly.
Evaluate
patient’s fluid
intake, urine
output, and urine
pH. Report
hematuria,
oliguria, or
anuria right
away.
Ciprofloxacin Inhibits Hypersensitivity to toxic psychosis Watch for signs
bacterial drug or other pseudo-membranous and symptoms
DNA fluoroquinolones colitis of serious
synthesis by Comcomitant methemoglobinemia, adverse
inhibiting administration of agranulocytosis, reactions,
DNA gyrase tizanidine hemolytic anemia including GI
in hepatic necrosis problems,
susceptible hyperkalemia jaundice, tendon
gram- erythema multiforme problems, and
negative and hypersensitivity
gram- reactions.
positive Instruct patient
organisms to stop taking
drug and notify
prescriber at first
sign of burning,
numbness, or
tingling in hands
or feet; yellow
eyes or skin;
unusual
tiredness;
persistent
diarrhea; rash; or
tendon pain,
swelling, or
inflammation.
Phenazopyridine act locally Hypersensitivity to Renal toxicity Monitor for
on urinary drug Hepatotoxicity yellowing of
tract mucosa Renal hemolytic anemia, skin or sclera.
to produce insufficiency methemoglobinemia This change may
analgesic or anaphylactoid-like indicate drug
anesthetic reaction accumulation
effects, caused by
relieving impaired renal
urinary excretion,
burning, warranting drug
urgency, and withdrawal.
frequency Advise patient to
contact
prescriber
promptly if
symptoms don’t
improve or if
skin or eyes
become yellow.
NURSING INTERVENTIONS
1. Nursing Assessment
a. Mild Symptoms
• Outpatient management or short hospitalization
Adequate fluid intake
Nonsteroidal anti-inflammatory drugs (NSAIDs) or antipyretic drugs
Follow-up urine culture and imaging studies
• Severe Symptoms
Hospitalization
Adequate fluid intake (parenteral initially; switch to oral fluids as nausea, vomiting, and dehydration
subside)
NSAIDs or antipyretic drugs to reverse fever and relieve discomfort
Follow-up urine culture and imaging studies
2. Nursing Planning
a. The overall goals are that the patient with pyelonephritis will have
Normal renal function
Normal body temperature
No complications
Relief of pain
No recurrence of symptoms
3. Nursing Implementation
a. Nursing interventions vary depending on the severity of symptoms.
b. These interventions include teaching the patient about the disease process with emphasis on
Continuing medications as prescribed
Having a follow-up urine culture
Recognizing manifestations of recurrence or relapse
In addition to antibiotic therapy, encourage the patient to drink at least eight glasses of fluid every day, even
after the infection has been treated.
Rest will increase patient comfort.
COMPLICATIONS
Acute pyelonephritis can have several complications such as renal or perinephric abscess formation, sepsis, renal vein
thrombosis, papillary necrosis, or acute renal failure, with one of the more serious complications being emphysematous
pyelonephritis (EPN). Emphysematous pyelonephritis is a necrotizing infection of the kidney usually caused by E. coli or
Klebsiella pneumoniae and is a severe complication of acute pyelonephritis. EPN is usually seen in the setting of diabetes
and occurs more frequently in women. The diagnosis can be made with ultrasound, but CT is typically necessary. Overall the
mortality rate is estimated to be approximately 38% with better outcomes associated with patients who receive both medical
and surgical management versus medical management alone.
