**7. References**

18 Will-be-set-by-IN-TECH

1 Use a continuous outcome variable (eg RAVC) n/a possibly ✔

4 Include hard outcomes (RRT, Death) ✔✔✔ 5 Include plasma cystatin C as an outcome n/a ✔ ✔

7 Measure 2 to 4-h creatinine clearance n/a ✔ ✔

The discovery of many early biomarkers of kidney injury has begun to shift the paradigm from assessment of change in filtration function to measurement of direct injury. Lest we throw the baby out with the bathwater we must recognise the complementary role of assessing both renal injury and renal function. Our techniques for assessing injury are still in their infancy, but show much promise. Our techniques for assessing function have a long history, yet, as we have shown, have room for improvement. In particular, we are learning to use appropriate surrogates of function, categorical or continuous, depending on the type of study we are conducting. We await the development of rapid, near "real-time" measures of function which are the missing link in enabling us to understand the temporal profile of injury in relation to functional change. We also look forward to an era of clinical trials which utilise the injury biomarkers discovered to date so as to properly test of drugs found to be effective soon after

2 Use RIFLE, AKIN or KDIGO definition as outcome variables (including for CIN trials)

3 Use a hierarchical-adjudicated approach to

8 Use corrected Δ*GFR*(%) for RIFLE classes R or F

8 Apply treatment within the time window following insult determined by experimental

9 Measure biomarkers within the time window following insult determined by experimental

10 Report urinary biomarker concentrations & concentrations normalised to urinary creatinine

11 Report median and inter-quartile range for

12 Report times and duration for which plasma

determine baseline creatinine

6 For subcohort analysis use KDIGO guidelines for CKD staging (Levey

(Pickering & Endre (2009a))

biomarker concentrations

outcomes were determined

Table 3. Practical considerations

injury in experimental models.

et al. (2003))

&/or pilot data

&/or pilot data

**5. Conclusion**

Epidemiology

Biomarker Studies

✔✔✔

✔✔✔

✔✔✔

n/a ✔ ✔

n/a n/a ✔

n/a ✔ n/a

n/a ✔ n/a

n/a ✔ n/a

✔✔✔

Clinical Trials


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**7** 

*India* 

Manisha Sahay

*Department of Nephrology* 

**Acute Kidney Injury in Pregnancy** 

*Osmania Medical College and General Hospital, Hyderabad, Andhra Pradesh* 

Acute kidney injury (AKI) is a life threatening complication of pregnancy.The incidence of AKI has sharply declined from 0.5 per 1000 pregnancies to one in 20,000 births in developed countries. (Beaufilis,2005) On the other hand, pregnancy is still responsible for 15–20% of AKI in developing countries. (Naqvi, 1996)Pregnancy related AKI (PRAKI) is on the decline

The kidney undergoes monumental physiologic and anatomic changes during a normal pregnancy. Renal plasma flow increases by 50-70%. Plasma volume increases by 50% and there is hemodilutional anemia. Cardiac output increases by 40%.Glomerular Filtration Rate (GFR) is maximum around the 13th week of pregnancy and can reach levels up to 150% of normal. Despite increased GFR the intraglomerular pressure remains normal. Serum creatinine falls by an average of 0.4 mg/dl to a pregnancy range of 0.4 to 0.8 mg/dl. Hence, a serum creatinine of 1.0 mg/dl, although normal in a non pregnant individual, reflects renal impairment in a pregnant woman. Serum creatinine rises near term and value of 1 mg/dl is considered normal. In the initial part of pregnancy there is decreased peripheral vascular resistance with a blood pressure fall of approximately 10 mm Hg in the first 24 weeks. The blood pressure gradually returns to prepregnancy level by term. Glycosuria occurs due to decrease in transport maximum for glucose(TMG) and high GFR. Aminoaciduria (2 g/d) may be seen. Increased uric acid clearance results in low uric acid level (2.5-5.5 mg/dl) but levels increase later and reach prepregnancy values at term. A value of >6 mg/dl reflects pregnancy induced hypertension (PIH). Potassium and almost 900 meq of sodium are retained. Calcium excretion increases but stone formation is not increased as there is increased excretion of inhibitors of stone formation. A reset in the osmostat occurs, resulting in increased thirst and decreased serum sodium levels ( by 5 mEq/L) and low plasma osmolality (10 m0sm/kg less ). Clearance of ADH is increased by placental vasopressinase and may result in transient Diabetes insipidus of pregnancy which may respond to DDAVP. On the other hand there are some reports of transient SIADH in pregnancy. Urine concentration and dilution are adequate. There is mild respiratory alkalosis and blood gas of 7.42-7.44/30

from 14.5% reported in 1987 to 4.3% in 2005 in India(Chugh,1987).

pCO2/HCO318-22 is representative (Chris Baylis,2007).

**1.1 Physiological changes in pregnancy 1.1.1Renal function during pregnancy** 

**1. Introduction** 

J. V. (2010). Kidney injury molecule-1 outperforms traditional biomarkers of kidney injury in preclinical biomarker qualification studies, *Nat Biotechnol* 28(5): 478–485.

