RENAL AND URINARY TRACT DISORDERS OF PREGNANCY (AB) Flashcards
Which hormone-induced change in pregnancy causes dilation of the renal calyces and ureters?
Progesterone-induced relaxation of the muscularis
Why is marked dilatation of the ureters more apparent in mid-pregnancy?
Increased distal ureteral compression, especially on the right side
What physiologic change in pregnancy increases the risk of upper urinary tract infections?
Vesicoureteral reflux
Why might imaging studies for urinary tract obstruction in pregnancy be misinterpreted?
Physiologic changes in the urinary tract can mimic obstruction
What renal structural change occurs during pregnancy without an increase in cell numbers?
Glomerular enlargement
What happens to renal plasma flow (RPF) and glomerular filtration rate (GFR) during pregnancy?
RPF increases by 40% and GFR by 65%
How do creatinine and urea levels change during pregnancy?
Both decline substantially
What is asymptomatic bacteriuria?
Persistent, actively multiplying bacteria in the urinary tract without symptoms
What is the diagnostic threshold for bacteriuria in a voided urine specimen?
≥105 colony-forming units (CFU)/mL
When do guidelines recommend screening for asymptomatic bacteriuria in pregnancy?
At the first prenatal visit
What should be done if a pregnant woman’s initial urine culture is positive?
Prompt treatment
Why might asymptomatic bacteriuria be treated at lower bacterial counts?
Pyelonephritis can develop even with 20,000-50,000 CFU/mL
What percentage of untreated asymptomatic bacteriuria cases develop symptomatic infection during pregnancy?
Approximately 25%
What are two cost-effective screening tests for asymptomatic bacteriuria in pregnancy?
Leukocyte esterase and nitrite dipstick tests
Is susceptibility testing always necessary for treating asymptomatic bacteriuria?
No, initial treatment is empirical
What is the single-dose treatment option for asymptomatic bacteriuria?
Amoxicillin 3g, Ampicillin 2g, Cephalosporin 2g, Nitrofurantoin 200mg, Trimethoprim-sulfamethoxazole 320/1600mg
What are common 3-day treatment regimens for asymptomatic bacteriuria?
Amoxicillin 500mg TID, Ampicillin 250mg QID, Cephalosporin 250mg QID, Ciprofloxacin 250mg BID, Levofloxacin 250-500mg daily, Nitrofurantoin 50-100mg QID or 100mg BID, TMP-SMX 160/800mg BID
What is the first-line treatment for recurrent bacteriuria in pregnancy?
Nitrofurantoin 100mg at bedtime for 21 days
What is the preferred suppressive therapy for persistent bacteriuria?
Nitrofurantoin 100mg at bedtime for the remainder of pregnancy
What is the most common cause of sepsis in pregnant patients?
Acute pyelonephritis
Which side is more commonly affected in acute pyelonephritis during pregnancy?
Right side
What are the hallmark symptoms of acute pyelonephritis?
Fever, shaking chills, lumbar pain
What physical exam finding suggests acute pyelonephritis?
Costovertebral angle tenderness
What are the common bacterial causes of acute pyelonephritis in pregnancy?
E. coli (70-80%), Group B Strep/S. aureus (10%), Klebsiella pneumoniae (3-5%), Enterobacter/Proteus spp (3-5%)
What is the cornerstone of acute pyelonephritis treatment?
Intravenous hydration
Why is plasma creatinine monitored in acute pyelonephritis?
5% of pregnant women develop renal dysfunction despite fluid resuscitation
What respiratory complication can occur in 10% of acute pyelonephritis cases?
Acute respiratory distress syndrome (ARDS)
What is a common hematologic complication of pyelonephritis?
Endotoxin-induced hemolysis leading to anemia
What is the initial antimicrobial therapy for acute pyelonephritis in pregnancy?
Ampicillin + Gentamicin, Cefazolin or Ceftriaxone, Extended-spectrum antibiotics
What are the key steps in managing acute pyelonephritis in a pregnant patient?
Hospitalization, urine and blood cultures, CBC, creatinine, electrolytes, IV fluids, IV antibiotics, chest X-ray if needed, monitor vitals and urinary output
What are the criteria for discharge after treating acute pyelonephritis?
Afebrile for 24 hours, completion of IV antibiotics, switch to oral antibiotics for 7-10 days
What should be done 1-2 weeks after finishing antibiotics for acute pyelonephritis?
Repeat urine culture
Why are pregnant women prone to nephrolithiasis?
Urinary pH elevation reduces calcium phosphate solubility
What is the most common type of kidney stone in pregnancy?
Calcium phosphate or hydroxyapatite
What is the primary symptom of nephrolithiasis in pregnancy?
Pain
What imaging modality is preferred for detecting nephrolithiasis in pregnancy?
Sonography
What sonographic sign may help rule out urinary obstruction?
Ureteral ‘jets’ on color Doppler
What dietary changes help prevent recurrent kidney stones?
Low sodium and low protein diet
What medication reduces the risk of recurrent nephrolithiasis?
Thiazide diuretics
What are the first-line treatments for nephrolithiasis in pregnancy?
Intravenous hydration and analgesics
When is nephrolithiasis an emergency in pregnancy?
When there is urinary obstruction with infection (‘pus under pressure’)
What percentage of symptomatic nephrolithiasis cases resolve with conservative management?
65-80%
What procedures may be required for persistent nephrolithiasis in pregnancy?
Ureteral stenting, ureteroscopy, percutaneous nephrostomy, transurethral laser lithotripsy, or basket extraction
What stone treatment is contraindicated in pregnancy?
Extracorporeal shock wave lithotripsy
What are the six syndromes of glomerular injury?
“Acute nephritic syndromes. pulmonary-renal syndromes. nephrotic syndromes. basement membrane syndromes. glomerular vascular syndromes. infectious disease-associated syndromes.”
What is the clinical presentation of acute nephritic syndrome?
“Hypertension. hematuria. red-cell casts. pyuria. proteinuria.”
What are the common complications of acute nephritic syndrome?
“Edema. hypertension. circulatory congestion. renal insufficiency.”
What is the most common form of acute glomerulonephritis worldwide?
“IgA nephropathy (Berger disease).”
What syndrome involves both glomerulonephritis and pulmonary hemorrhage?
“Goodpasture syndrome.”
What is the prognosis of acute nephritic syndrome?
“Varies by etiology; some recede spontaneously. others lead to rapidly progressive glomerulonephritis or chronic glomerulonephritis.”
What is the hallmark feature of nephrotic syndrome?
“Heavy proteinuria.”
What are the key characteristics of nephrotic syndrome?
“Hypoalbuminemia. hypercholesterolemia. edema.”
What are common causes of nephrotic syndrome?
“Minimal change disease. focal segmental glomerulosclerosis. membranous glomerulonephritis. diabetic nephropathy.”
What are potential complications of nephrotic syndrome?
“Hypertension. renal insufficiency. arterial and venous thrombosis. renal vein thrombosis.”
What factors increase thromboembolism risk in nephrotic syndrome?
“Platelet hyperactivity. urinary loss of antithrombotic factors. increased prothrombotic factor production by the liver.”
How does nephrotic syndrome affect pregnancy outcomes?
“Outcomes depend on severity; increased risk of preeclampsia. edema. chronic hypertension. renal insufficiency.”
What are the worst prognostic indicators for pregnancy outcomes in nephrotic syndrome?
“Serum creatinine >1.4 mg/dL. 24-hour protein excretion >1 g/day.”
What is a common renal biopsy finding in nephrotic syndrome?
“Microscopic abnormalities that guide treatment.”
What dietary recommendation is given for nephrotic syndrome?
“Normal amounts of high-biological-value protein.”
What are the main treatments for nephrotic syndrome?
“Glucocorticosteroids. immunosuppressants. cytotoxic drugs. treating underlying causes.”
What is the risk of chronic hypertension in pregnant women with nephrotic syndrome?
“Up to half of affected women may require treatment for chronic hypertension.”
What is the relationship between nephrotic syndrome and preeclampsia?
“Preeclampsia is common and often develops early in pregnancy.”
How does pregnancy impact proteinuria in nephrotic syndrome?
“Daily protein excretion may rise as pregnancy progresses.”
What is a common sign of severe edema in pregnant women with nephrotic syndrome?
“Massive vulvar edema.”
What is chronic kidney disease (CKD)?
A pathophysiological process that can progress to end-stage renal disease.
What are the six stages of chronic kidney disease based on GFR?
Stage 0: GFR > 90 ml/min/1.73m²; Stage 5: GFR < 15 ml/min/1.73m².
What are the leading causes of end-stage renal disease requiring dialysis or transplantation?
Diabetes (35%), Hypertension (25%), Glomerulonephritis (20%), Polycystic kidney disease (15%).
How is renal function categorized based on serum creatinine levels?
Normal/Mild: <1.5 mg/dL; Moderate: 1.5–3.0 mg/dL; Severe: >3.0 mg/dL.
What are the major risks of pregnancy in women with chronic renal disease?
High incidence of hypertension, preeclampsia, preterm birth, growth restriction, and worsening renal function.
How does pregnancy affect renal plasma flow and GFR in women with mild renal insufficiency?
Pregnancy increases renal plasma flow and GFR.
How does severe chronic renal insufficiency affect blood volume expansion during pregnancy?
It curtails normal pregnancy-induced hypervolemia, leading to only 25% volume expansion.
What common hematologic condition is seen in women with chronic renal disease?
Chronic anemia due to intrinsic renal disease.
What are the key lab values monitored in chronic renal insufficiency during pregnancy?
Serum creatinine, protein/creatinine ratio, 24-hour protein excretion.
Why is bacteriuria treated in women with chronic kidney disease?
To decrease the risk of pyelonephritis and further nephron loss.
What dietary recommendation is given for chronic kidney disease?
Protein-rich diet.
What is a common side effect of recombinant erythropoietin used for anemia in CKD?
Hypertension.
What imaging modality is used to monitor fetal growth in CKD pregnancies?
Serial sonography.
What biomarkers may help differentiate chronic hypertension from preeclampsia?
Placental growth factor (PlGF) and soluble fms-like tyrosine kinase 1 (sFlt-1).
How can pregnancy accelerate chronic renal disease progression?
By increasing hyperfiltration and glomerular pressure, leading to worsening nephrosclerosis.
What is a marker for the future development of renal failure?
Chronic proteinuria.
When is dialysis recommended during pregnancy?
When serum creatinine levels reach 5–7 mg/dL.
Why is dialysis frequency increased during pregnancy?
To avoid abrupt volume changes that can cause hypotension.
What key substances must be replaced during dialysis in pregnancy?
Multivitamins, calcium, iron salts, dietary protein, and calories.
What maternal complications are common in pregnancy with dialysis?
Severe hypertension, placental abruption, heart failure, sepsis.
What fetal complications are associated with maternal dialysis?
Preterm birth, growth restriction, stillbirth, and hydramnios.
What is acute kidney injury (AKI)?
Sudden impairment of kidney function with retention of nitrogenous waste products.
What are common causes of acute renal ischemia in pregnancy?
Severe preeclampsia, hemorrhage, HELLP syndrome, placental abruption, septicemia.
How is AKI typically diagnosed?
An abrupt rise in serum creatinine and oliguria.
What is the first-line management of AKI in pregnancy?
Volume replacement and treatment of underlying causes.
When is renal replacement therapy (dialysis/hemofiltration) indicated in AKI?
When severe oliguria and azotemia persist.
Which medications require dose adjustment in AKI?
Magnesium sulfate, iodinated contrast agents, aminoglycosides, NSAIDs.
What is the role of early dialysis in AKI?
It reduces maternal mortality.
What is the most common cause of AKI in obstetrics?
Acute blood loss, often associated with preeclampsia or massive hemorrhage.
What are the key strategies to prevent AKI in obstetric patients?
Prompt fluid replacement, early delivery in severe preeclampsia, monitoring for sepsis, avoiding unnecessary vasoconstrictors and diuretics.
