Acute Pyelonephritis
Definition
Acute pyelonephritis is a bacterial infection of the renal pelvis and kidney tissue. It is usually sudden in onset and produces fever and flank pain.
Causes / Etiology
Most often caused by ascending infection from the lower urinary tract.
Common organisms: Escherichia coli, Klebsiella, Proteus, Staphylococcus aureus.
Risk factors: urinary obstruction, vesicoureteric reflux, catheterisation, pregnancy, diabetes.
Types or Classification
Acute pyelonephritis – sudden infection with fever, pain and pyuria.
Chronic (recurrent) pyelonephritis – repeated bouts leading to scarring and loss of renal function.
Pathology (stepwise)
Step 1 → Bacteria colonise the peri‑urethral area and ascend the ureter.
Step 2 → They reach the renal pelvis and multiply in the urine.
Step 3 → Bacterial toxins and inflammatory cells invade the renal parenchyma.
Step 4 → Interstitial oedema, tubular necrosis and pus formation develop.
Step 5 → If untreated, abscesses or permanent scar tissue may form.
Clinical Features
General – high fever, chills, malaise, loss of appetite, nausea, vomiting.
Specific – sharp flank (costovertebral) pain, dysuria (painful urination), increased frequency, urgency, haematuria (blood in urine), cloudy urine, possible palpable tender kidney.
Complications
Acute – renal or perinephric abscess, sepsis, acute renal failure, electrolyte imbalance.
Chronic – renal scarring, chronic kidney disease, hypertension, recurrent infections, papillary necrosis.
Diagnosis / Investigations
Routine –
• Urinalysis: pyuria (pus cells), bacteriuria, haematuria.
• Urine culture: identifies causative organism and antibiotic sensitivity.
• Blood count: leukocytosis, raised ESR/CRP.
• Blood culture if systemic signs present.
Special –
• Renal ultrasound: enlarged kidney, loss of corticomedullary differentiation, abscess detection.
• CT abdomen (contrast) – detailed view of abscess, obstruction or calculi.
• X‑ray KUB (if stones suspected).
Management
General – bed rest, adequate hydration (2–3 L water/day), analgesics for pain, antipyretics for fever.
Modern treatment – empirical broad‑spectrum oral antibiotics (e.g., ciprofloxacin 500 mg BID) pending culture; switch to organism‑specific drug once sensitivity known. Severe cases need IV antibiotics (e.g., ceftriaxone) and possible hospitalisation.
Dietary advice – high fluid intake, avoid caffeine and alcohol, light protein diet, cranberry juice or unsweetened cranberry extract may reduce bacterial adhesion.
Homeopathic Therapeutics (key remedies, bullet points)
Cantharis
- Burning pain in the urethra and kidneys, worse on urination.
- Urine appears cloudy with a strong, foul smell.
- Thirst for cold water, but relief only when drinking ice‑cold water.
- Fever with chills, feeling of heat in the lower back.
- Worse at night, especially when lying on the affected side.
- Good for patients who are irritable and restless.
Apis mellifica
- Sudden onset of fever with hot, flushed skin.
- Swelling of the flank, painful to touch, relieved by cold applications.
- Urine may be scanty, with a stinging sensation during micturition.
- Patient feels better with cool drinks, worse from warmth.
- Great thirst for cold water, especially ice.
- Useful when there is a history of insect bite or allergic tendency.
Belladonna
- Intense, throbbing flank pain that comes on rapidly.
- High fever, face red, pupils dilated, patient feels hot and dry.
- Urine may be scanty, with burning on passing.
- Restlessness, agitation, patient wants to be alone.
- Worse from warmth, better from cold compresses.
- Good for early stage with sudden, violent symptoms.
Nux vomica
- Pain in the kidney region that is worse after over‑indulgence in food, alcohol or stimulants.
- Irritable, impatient, feels better after vomiting or purging.
- Urine may be dark, with a feeling of incomplete emptying.
- Low‑grade fever, headache, constipation.
- Patient is sensitive to noise and light.
- Useful when the patient is a hard‑working, over‑strained individual.
Mercurius solubilis
- Burning, tearing pain in the flank with excessive salivation.
- Urine is foul‑smelling, may contain mucus or pus.
- Patient feels chilly, with alternating hot and cold sensations.
- Swelling of the perineal region, soreness on pressure.
- Thirst for cold water, but drinks little.
- Good when there is a history of chronic urinary irritation or after dental infections.