Acute Pyelonephritis: Etiology, Risks & Comorbidities

• Acute pyelonephritis signifies a severe kidney infection, leading to swelling and potential urinary obstructions, rarely chronic.
• It typically arises from a lower urinary tract infection (UTI), where bacteria travel from the urethra to the bladder, multiply, and then ascend to the kidneys via the ureters.
• Kidney damage impairs fluid and electrolyte balance due to disrupted plasma osmolarity regulation.

Etiology

• Gram-negative bacteria, commonly E. coli from fecal matter, are the usual cause.

Risk Factors

• Conditions obstructing normal urine flow increase the risk of developing acute pyelonephritis.
• Females are at higher risk due to shorter urethras.
• Additional risk factors: renal stones, kidney/bladder disorders, immunosuppression, enlarged prostate, urinary catheters, cystoscopic procedures, and certain medications.

Comorbidities

• Diabetes is linked to emphysematous pyelonephritis, a necrotizing infection destroying kidney tissues.
• Other complications: renal abscesses, renal vein thrombosis, and acute renal failure.

Epidemiology

• In the United States, approximately 15-17 cases per 10,000 females and 3-4 cases per 10,000 males occur annually.
• Young, sexually active females are the most commonly affected group.
• Risk increases during the second and third trimesters of pregnancy.

Clinical Manifestations

• Symptoms usually appear 48 hours after infection onset.
• Common manifestations: fever over 102° F, side/back/groin pain, dysuria, cloudy/bloody urine, and fishy urine odor.
• Other symptoms: chills, nausea, vomiting, fatigue, and mental confusion.
• Chronic pyelonephritis may present with slight/no symptoms unless an acute infection occurs or chronic kidney disease is present.
• Older adults may be asymptomatic or present with new-onset confusion.

Effects of Pyelonephritis

• Kidney swelling from pyelonephritis can cause permanent kidney damage, leading to kidney failure.
• Kidney damage leads to fluid overload manifestations like weight gain and edema.
• Fever may exceed 102° F.
• Pain may occur.
• Dysuria may occur.
• Cloudy or bloody urine may occur.
• Urine may have an unusual odor.
• Older adults may be asymptomatic or have new onset confusion.

Diagnostic Tests

• Urinalysis assesses for blood, urine concentration, and bacteria.
• Renal ultrasound views kidney structures for cysts, tumors, or obstructions.
• Dimercaptosuccinic acid (DMSA) test (radioactive imaging) reveals any scarring in the urinary tract due to pyelonephritis.

Nursing Interventions

• Educate clients on disease prevention: maintain adequate hydration to flush bacteria, urinate after intercourse, wipe from front to back, and avoid feminine sprays/douches.
• Perform a health history, including previous urinary infections and past medical history, and history of present illness.
• Assess the client's abdomen and flank areas for pain.
• Ask about discomfort with urination or blood in the urine, especially in females.
• Confusion may be present in older adult clients with or without fever.
• Monitor vital signs for elevated temperature.
• Complete diagnostic tests, including urinalysis/culture, CBC, and abdominal/pelvic CT with contrast.
• Conduct a focused assessment related to urinary manifestations such as dysuria, polyuria, urgency, and changes in urine color and odor.
• Conduct a pain assessment to assess the client for pain, heaviness, or pressure in the back, flank, or abdominal areas, which may radiate to the groin.
• Assess the flank area for tenderness, edema, or redness, which may indicate inflammation.
• Monitor laboratory tests for the presence of bacteria showing infection and kidney function tests such as BUN and creatinine.

Risks

• Pyelonephritis can lead to scarring of the kidney parenchyma, sepsis, shock, or acute renal failure.
• If the urinalysis indicates the presence of nitrates, immediately notify the healthcare provider.
• E. coli or Klebsiella pneumoniae can lead to emphysematous pyelonephritis, causing kidney necrosis.

Planning and Implementation

• Determine if the pyelonephritis is uncomplicated or complicated, aiming to eradicate the infection and prevent future occurrences.
• Uncomplicated pyelonephritis: outpatient treatment with a 14-day oral antibiotic course.
• Educate the client on measures to prevent future episodes.
• Complicated pyelonephritis (pregnancy, uncontrolled diabetes, kidney transplant recipient, immunocompromised, or renal failure): hospital admission, IV antibiotics, pain medications, and antipyretics.
• Teaching includes preventing future episodes and managing comorbidities.
• Administer prescribed antibiotics and antipyretics like acetaminophen for fever and pain.
• Increase fluids to promote urine dilution and bacterial flushing.
• Encourage frequent voiding to prevent bladder distention and urine stasis.

Evaluation

• Successful outcomes: client is free of pain and fever, urinalysis shows no nitrates, pyuria, or blood, and CBC, BUN, and creatinine levels are within normal limits.

Medications

• Anti-infectives like levofloxacin, ciprofloxacin, co-trimoxazole, and ampicillin treat acute pyelonephritis.
• Intravenous antibiotics and hydration may be followed by oral antibiotics for 10 to 14 days.

levofloxacin (Levaquin) and ciprofloxacin (Cipro)

• Fluoroquinolones, prevent bacterial DNA synthesis.
• Levaquin is contraindicated in clients who have a history of myasthenia gravis and who have or are at risk for an aortic aneurysm and should be used cautiously in those who have a seizure disorder, kidney impairment, or depression.
• Adverse effects: increased cranial pressure, seizures, aortic aneurysm dissection, polymorphic ventricular tachycardia, diarrhea from Clostridium difficile, Stevens-Johnson syndrome.
• Can be taken orally or IV daily.
• Take as directed; avoid antacids, iron, or zinc within 2 hours.
• Wear sunscreen and protective clothing; report tingling/numbness, diarrhea, jaundice, or rash.

co-trimoxazole

• Sulfonamide.
• Inhibits folic acid synthesis. Effective against positive cocci, gram-negative bacilli, and some protozoa/fungi.
• Monitor for Stevens-Johnson syndrome.
• Can decrease oral contraceptive effectiveness; use alternate contraception.

ampicillin

• Penicillin.
• Causes bacterial cell death by attaching to the cell wall.
• Contraindicated in penicillin allergies; use cautiously with severe renal impairment, acute hemolytic leukemia, or infectious mononucleosis.
• Adverse effects: seizures, rash, diarrhea from Clostridium difficile, elevated liver enzymes, and superinfections.
• Taken twice daily.
• Report hypersensitivity manifestations (rash, breathing difficulty, diarrhea, abdominal pain, blood in stools).
• Female clients using oral contraceptives should use additional contraception.

Fluoroquinolones

• Cause death of susceptible bacterial cells by inhibiting the two enzymes necessary for replication of DNA and cell division.
• Monitor for Achilles tendon rupture.
• Can cause GI side effects.
• May cause phototoxic reaction; clients should wear sunscreen.

Sulfonamide

• Inhibit folic acid synthesis. They are also bacteriostatic antibiotics and are effective against positive cocci, gram-negative bacilli, and some protozoa and fungi.
• Monitor for Stevens-Johnson syndrome.
• Sulfonamides can decrease the effectiveness of oral contraceptives.
• Teach clients to use an alternate form of contraceptive during therapy.

Penicillin

• Weaken and destroy the cell wall of bacteria that are sensitive.
• Use cautiously with severe renal impairment.
• Report rash, hives, watery or bloody diarrhea to the Healthcare Provider (HCP).

This lesson covers acute pyelonephritis, a severe kidney infection usually caused by bacteria like E. coli. It discusses how UTIs can ascend to the kidneys, leading to swelling and potential obstructions. Risk factors, including urinary obstructions and comorbidities like diabetes, are also explored.