Thrombotic microangiopathy (TMA) associated pregnancy acute kidney injury (AKI) is rare but isreported to be increasing.
TMA associated pregnancy AKI is associated with high morbidity and mortality for both motherand baby.
Further understanding of risk factors, timing of onset and anticipated recovery is required to assist with earlier diagnosis and treatment, thus reducing longterm morbidity and mortality.
1st July 2021 – 30th June 2022
Acute kidney injury (AKI) is defined as a rapid reduction in kidney function. Thromboticmicroangiopathies (TMAs), characterised by microangiopathic haemolytic anaemia, thrombocytopeniawith AKI, are rare in pregnancy but are associated with very high morbidity and mortality for mother andbaby1,2. Diagnostic delays and failure to give prompt treatment can be life-threatening3, and may lead tolongterm requirements for costly renal replacement therapy for the mother and ongoing care associatedwith prematurity for the infant.Women with pregnancy associated AKI in high-income countries are more likely to die compared tothose unaffected4 and fetal mortality and morbidity is also elevated with higher risk of stillbirth/fetaldeath, significantly reduced birthweight and early delivery for infants of women with pregnancy AKI4.Furthermore, AKI is no longer considered to be a benign event with complete recovery, and is arecognised risk factor for future chronic kidney disease, cardiovascular events and pre-eclampsia5,6 andincreases healthcare costs.The incidence of pregnancy AKI is rare but reported to be increasing. Severe pregnancy AKI is poorlydescribed making early diagnosis and intervention challenging for clinicians. Improved understanding ofrisk factors, timing of onset and anticipated recovery could lead to earlier diagnosis and treatmentwhich would in turn reduce longterm morbidity and mortality known to be associated with the condition.These data will also provide important information to underpin future intervention studies to improveoutcomes of pregnancy associated TMA with AKI.
To use the UK Obstetric Surveillance System (UKOSS) to describe the incidence, risk factors, currentmanagement and outcomes of pregnancy associated thrombotic microangiopathy (TMA) with severeacute kidney injury (AKI).
What is the incidence of thrombotic microangiopathy associated pregnancy acute kidney injury(AKI) in the UK?
What are the characteristics of women with thrombotic microangiopathy associated pregnancyAKI?
What are maternal (including renal) and neonatal outcomes associated with thromboticmicroangiopathy associated pregnancy AKI?
All pregnant women who meet the following criteria:
A rise in serum creatinine to >250 mmol/l
platelet count <150x109
at least one evidence of haemolysis (fragments on blood film, haptoglobin below lower limit ofnormal or lactate dehydrogenase above upper limit of normal).
Excluded: All women established on renal replacement therapy prior to the acute AKI episode.
This study is funded by a study grant from Alexion.
Ethics committee approval
This study has been approved by the North London REC1 (Ref. Number: 10/H0717/20).
Kate Bramham, Katherine Clark, Lisa Long, King's College London
Catherine Nelson-Piercy, Marlies Ostermann, Anita Banerjee, Guy's and St Thomas' Hospital
Edwin Wong, Neil Sheeran, Royal Victoria Infirmary, Newcastle upon Tyne
Dashe JS, Ramin SM, Cunningham FG. The long-term consequences of thromboticmicroangiopathy (thrombotic thrombocytopenic purpura and haemolytic uremic syndrome) inpregnancy. Obstetrics and Gynecology, 1998. 91:662-8.
Vesely SK et al. ADAMTS13 activity in thrombotic thrombocytopenic purpura-hemolytic uremicsyndrome: Relation to presenting features and clinical outcomes in a prospective cohort of 142patients. Blood, 2003. 102:60-68.
Chua J et al. Suspected atypical haemolytic uraemic syndrome in two post-partum patients withfoetal-death in utero responding to eculizumab. Nephrology, 2017. 22:18e22.
Liu S et al. Temporal trends and regional variations in severe maternal morbidity in Canada,2003 to 2007. Journal of Obstetrics and Gynaecology Canada, 2010. 32:847-855.
Chertow GM et al. Acute kidney injury, mortality, length of stay, and costs in hospitalizedpatient. Journal of the American Society of Nephrology, 2005. 16:3365-3370.