Adult-Gerontology Acute Care Practice Guidelines
Definition
A.An infection (usually from bacteria but also from viruses, fungi, or parasites) that results in swelling of the kidney. It may affect one or both kidneys.
1.Uncomplicated.
2.Complicated—associated with obstruction, anatomic anomaly, or kidney stones.
Incidence
A.Population-based study of acute pyelonephritis in the United States found overall annual rates of 15 to 17 cases per 10,000 females and 3 to 4 cases per 10,000 males.
B.At least 250,000 cases of pyelonephritis are diagnosed annually in the United States.
Pathogenesis
A.Usually results from bacterial invasion by ascending from the lower urinary tract (urethra and bladder).
B.Can result from colonization of the vagina with fecal flora.
C.Hematogenous source—from bloodstream infection that reaches renal parenchyma (uncommon). Most likely gram-positive organisms from endocarditis.
D.Evidence suggests that bacteria attaches to the urothelium and causes an inflammatory response. Hemolysins allow for bacterial invasion by damaging cells. Infection is most commonly associated with gram-negative bacteria such as Escherichia coli and Klebsiella pneumoniae.
Predisposing Factors
A.Female sex: Shorter urethra, allowing organisms to ascend to bladder and kidneys.
B.Functional abnormalities: High post void residuals or incomplete bladder emptying, neurogenic bladder.
C.Anatomic conditions: Bladder outlet obstruction/BPH or vesicoureteral reflux.
D.Chronic indwelling catheters.
E.Nephrolithiasis.
F.Diabetes mellitus.
G.Immunosuppression.
H.Alcohol or drug abuse.
I.Previous history of pyelonephritis.
J.Pregnancy.
K.New or multiple sexual partners.
L.History of recent cystitis.
Subjective Data
A.Common complaints/symptoms.
1.Flank pain.
2.Fever.
3.Nausea and vomiting.
4.Weakness.
5.Dysuria.
6.Foul-smelling urine.
7.Hematuria.
B.Common/typical scenario.
1.Onset: Abrupt, usually 1 to 2 days of symptoms.
2.Location/character.
a.Sharp and persistent flank pain in one or both kidneys.
b.Abdominal pain, suprapubic tenderness.
c.Possible groin pain.
d.Strong urge to urinate.
e.Burning on urination.
3.Fevers/chills: Generally feeling unwell.
4.Possible past medical history of kidney stones, pyelonephritis, or neurogenic bladder with chronic indwelling catheter.
C.Family and social history.
1.Family history.
a.Congenital anomalies of genitourinary (GU) tract.
b.Nephrolithiasis.
c.Diabetes mellitus.
d.History of frequent urinary tract infections (UTIs).
2.Social history.
a.Alcohol use.
b.Drug use (intravenous [IV] drug abuse may be associated with hematogenous spread of staphylococcal infection to kidney).
c.Multiple sexual partners.
d.New sexual partners.
e.Use of spermicide.
f.Poor perineal hygiene (fecal incontinence, soiling).
D.Review of systems.
1.Constitutional: Fevers, chills, or malaise.
2.Cardiovascular: Palpitations or fast heart rate.
3.Gastrointestinal—nausea and vomiting, abdominal pain, fecal incontinence.
4.Genitourinary—flank pain, dysuria, foul-smelling urine, hematuria, urgency/frequency, incontinence.
5.Neurological—confusion and dizziness, especially in elderly.
6.Gynecologic—vaginal discharge.
7.Endocrine—polyuria, polydipsia, polyphagia (symptoms of diabetes), night sweats.
Physical Examination
A.Vital signs: Evaluate for systemic inflammatory response/sepsis.
1.Fever.
2.Tachycardia.
3.Hypotension.
B.Generalized: Check to see if the patient appears ill; he or she may have rigors.
C.Genitourinary—evaluate for cerebrovascular accident (CVA) tenderness (positive in most cases on side of infected kidney).
D.Abdominal—evaluate for suprapubic tenderness (without guarding) and rigidity to rule out other causes of abdominal pain (e.g., acute abdomen, appendicitis).
E.Respiratory—assess for crackles, decreased breath sounds (signs of pneumonia).
F.Gynecological examination—perform if necessary in females to rule out gynecological disorder or pelvic inflammatory disease.
Diagnostic Tests
A.Blood work.
1.Complete blood count (CBC) with differential: Leukocytosis with neutrophil predominance.
2.Basic metabolic panel: Renal failure. Uncommon unless obstruction or sepsis is present.
3.Blood culture: Possible bacteremia.
B.Urinalysis.
1.Pyuria greater than 5 to 10 white blood cells (WBCs)/high power field (HPF).
2.Leukocytes positive.
3.WBC casts: Often indicative of pyelonephritis.
4.Nitrites: Positive in most cases if infection caused by gram-negative bacteria.
5.Red blood cells (RBCs): May be positive.
C.Urine culture.
1.Positive with greater than 100,000 bacteria/mL; 10,000 bacteria/mL in patients with catheterized urine samples.
2.Possibly negative if the patient was on antimicrobials prior to presentation.
D.Imaging: Not necessary in uncomplicated pyelonephritis but failure to respond to appropriate therapy requires imaging to rule out ureteral obstruction or abscess.
1.Abdominal x-ray (kidney–ureter–bladder [KUB]): Stones, intraparenchymal gas; may be emphysematous pyelonephritis.
2.CT scan (non contrast): Enlarged kidney with perinephric fat stranding.
3.Renal ultrasound: Imaging modality of choice for pregnant females (no radiation).
a.Shows renal enlargement with hypoechoic parenchyma and loss.
Differential Diagnosis
A.Abdominal disorders.
1.Appendicitis.
2.Cholecystitis.
3.Pancreatitis.
4.Diverticulitis.
5.Peptic ulcer disease.
B.Gynecologic disorders.
1.Ectopic pregnancy.
2.Pelvic inflammatory disease.
3.Ruptured ovarian cyst.
C.Urologic disorders.
1.Nephrolithiasis.
2.Epididymitis.
3.Renal or perinephric abscess.
4.Urethritis.
5.Cystitis.
Evaluation and Management Plan
A.General plan.
1.See Figure 5.2.
2.Obtain urinalysis and urine culture.
3.Obtain blood work: CBC, blood cultures, and basic metabolic panel.
4.Start broad-spectrum antibiotics.
a.Can tolerate oral agents (e.g., ciprofloxacin, trimethoprim, and sulfamethoxazole). Nitrofurantoin should be avoided (does not penetrate kidney well).
b.Unable to tolerate oral agents (e.g., ampicillin 2 g IV every 6 hours and gentamicin 1.5 mg/kg every 8 hours).
5.Use imaging studies for high suspicion of ureteral obstruction and abscess.
6.Hospitalize patients who have systemic inflammatory response syndrome (SIRS), sepsis, dehydration, or uncontrollable pain.
7.Consult urology if ureteral obstruction is found for stent placement or possible percutaneous nephrostomy drain.
B.Patient/family teaching points.
1.Increase fluids to promote hydration and flushing of the bacteria.
2.Encourage good hygiene and wiping from front to back after urinating to prevent bacteria from colonizing the urethra.
3.Urinate after sexual intercourse to help wash away bacteria.
4.Counsel patient and family that the patient may continue to have fever and flank pain for 2 to 3 days after appropriate treatment has been given.
5.Reinforce the importance of completing antibiotics for the recommended 14- to 21-day course.
C.Pharmacotherapy.
1.Once urine culture has finalized, switch to an appropriate antimicrobial for 14 to 21 days. Oral antibiotics can be used depending on susceptibilities.
2.Supportive care.
a.Phenazopyridine as possible help for dysuria.
b.Antipyretics such as acetaminophen to control fever.
c.Analgesics for appropriate pain management.
d.IV fluid hydration to prevent and treat dehydration and sepsis.
D.Discharge instructions.
1.Advise patients to seek medical care for any recurrent symptoms such as fevers, flank pain, nausea, and vomiting.
2.Advise patients to call if they are unable to tolerate oral antibiotic or develop adverse effects such as rash or diarrhea.
3.Advise patients to drink plenty of fluids.
Follow-Up