Assessment of proteinuria in hypertensive disorders in pregnancy

• interpret proteinuria measurements for pregnant women in the context of a full clinical review of symptoms, signs and other investigations for pre-eclampsia
  
  
• use an automated reagent-strip reading device for dipstick screening for proteinuria in pregnant women in secondary care settings
  
  
• if dipstick screening is positive (1+ or more), use albumin:creatinine ratio or protein:creatinine ratio to quantify proteinuria in pregnant women
  
  
• do not use first morning urine void to quantify proteinuria in pregnant women
  
  
• do not routinely use 24-hour urine collection to quantify proteinuria in pregnant women
  
  
• if using protein:creatinine ratio to quantify proteinuria in pregnant women:
  • use 30 mg/mmol as a threshold for significant proteinuria
  • if the result is 30 mg/mmol or above and there is still uncertainty about the diagnosis of pre-eclampsia, consider re-testing on a new sample, alongside clinical review
    
    
• if using albumin:creatinine ratio as an alternative to protein:creatinine ratio to diagnose pre-eclampsia in pregnant women with hypertension:
  • use 8 mg/mmol as a diagnostic threshold
  • if the result is 8 mg/mmol or above and there is still uncertainty about the diagnosis of pre-eclampsia, consider re-testing on a new sample, alongside clinical review

NICE have defined pre-eclampsia as (1):

• new onset of hypertension (over 140 mmHg systolic or over 90 mmHg diastolic) after 20 weeks of pregnancy and the coexistence of 1 or more of the following new-onset conditions:
  
  
  • proteinuria (urine protein:creatinine ratio of 30mg/mmol or more or albumin:creatinine ratio of 8mg/mmol or more, or at least 1 g/litre [2+] on dipstick testing) or
    
    
  • other maternal organ dysfunction:
    • renal insufficiency (creatinine 90 micromol/litre or more, 1.02 mg/100 ml or more)
    • liver involvement (elevated transaminases [alanine aminotransferase or aspartate aminotransferase over 40 IU/litre] with or without right upper quadrant or epigastric abdominal pain)
    • neurological complications such as eclampsia, altered mental status, blindness, stroke, clonus, severe headaches or persistent visual scotomata
    • haematological complications such as thrombocytopenia (platelet count below 150,000/microlitre), disseminated intravascular coagulation or haemolysis
      
      
  • uteroplacental dysfunction such as fetal growth restriction, abnormal umbilical artery doppler waveform analysis, or stillbirth

Reference:

• 1) NICE (June 2019). Hypertension in pregnancy - the management of hypertensive disorders during pregnancy