Chronic kidney disease in pregnancy — structured SAQ (15 marks)

(a) What is abnormal (3 marks)

One mark per point, maximum three. ^[1][3]

• Serum creatinine 96 micromol/L is abnormal in pregnancy. In normal pregnancy the GFR rises 40-50% and creatinine falls to roughly 44-60 micromol/L. A creatinine above 75 micromol/L is abnormal; 96 is markedly abnormal and signals significant CKD Stage 3.
• PCR 75 mg/mmol is abnormal (above the 30 mg/mmol threshold), indicating significant proteinuria consistent with her transplant and underlying disease.
• The trajectory matters: pre-pregnancy 88, booking 96 — the creatinine has not fallen as expected. A gestational fall in creatinine of less than 10% from pre-pregnancy doubled delivery before 34 weeks (20% to 40%) in women with chronic hypertension in CKD Stage 3-5.

(b) Immediate pharmacological management (4 marks)

One mark per intervention with drug, dose and rationale. ^[1][12]

• Aspirin 150 mg nocte from now (12 weeks) until 36 weeks — preeclampsia prophylaxis.
• Blood pressure control to under 140/90: labetalol 100-200 mg BD (max 800 mg/day) or nifedipine MR 20-60 mg daily — she has chronic hypertension on no treatment.
• Continue tacrolimus, azathioprine, hydroxychloroquine and prednisolone — all pregnancy-safe; check tacrolimus trough and dose up if low (clearance rises in pregnancy).
• Confirm she is NOT on mycophenolate, ACE inhibitor or statin — these were appropriate pre-conception switch targets.

(c) Surveillance plan (4 marks)

One mark per element. ^[3][7][11]

• Joint renal-obstetric clinic, every 4 weeks — renal function, blood pressure, proteinuria, tacrolimus trough.
• PlGF every 4 weeks from 20 weeks — a PlGF below 150 pg/mL predicts superimposed preeclampsia within 14 days (NPV 97%). The sFlt-1:PlGF ratio does not usefully predict delivery need in CKD serum, so trend PlGF itself.
• Serial growth scans with umbilical artery Doppler every 4 weeks from 24 weeks — fetal growth restriction risk.
• Lupus monitoring every 4-6 weeks — complement C3, C4, dsDNA titre; check anti-Ro/La status for neonatal lupus surveillance.

(d) Delivery and postpartum plan (4 marks)

One mark per element. ^[3][11]

• Planned delivery at 37-38 weeks for stable disease; earlier if superimposed preeclampsia, deteriorating function or fetal compromise.
• Vaginal birth preferred unless graft obstructs labour or obstetric indication for caesarean.
• Postpartum renal re-baseline at 6-12 weeks; nephrology follow-up indefinitely. Tacrolimus trough monitoring continues; seek pharmacist and nephrology advice on breastfeeding compatibility of each immunosuppressant.
• Reassess VTE risk; aspirin stops at 36 weeks but thromboprophylaxis is reassessed postpartum.