Identifying the risk of acute kidney injury in primary care

It is thought that up to 60% of acute kidney injury (AKI) cases presented in hospital begin in primary care[1]
. In the UK, AKI costs the NHS over £1bn each year[2]
. Up to one-fifth of patients admitted to hospital in an emergency have AKI, which, if untreated, can lead to chronic kidney disease (CKD), end-stage renal failure and death[3]

Guidance exists to treat acutely ill patients presenting in secondary care with AKI. Risk factors to developing AKI include: diagnosis with CKD (estimated glomerular filtration rate [eGFR]<60ml/min), heart failure, liver disease, dementia, diabetes, history of AKI, taking medicines of nephrotoxic potential such as angiotensin-converting enzyme inhibitors, diuretics and angiotensin receptor blockers, and being aged over 65 years old combined with an episode of dehydration due to fever, vomiting, diarrhoea or reduced fluid intake. The ‘Think kidneys’ campaign, supported by NHS England, recommends that calculators are applied in the community to predict future community acquired AKI and the need for hospital admission.

An audit was conducted over one week in January 2017 to identify hypertensive patients within primary care at increased risk of AKI. A secondary aim was to develop a set of repeatable audit criteria and an implementation plan that may protect patients against future avoidable harm from AKI.

Standards assessed include whether renal function had been checked in the past 12 months, whether patients had received ‘sick day rules’ advice and whether patients with eGFR<60ml/min/1.73m2 are on the practice CKD register classified as CKD stages G3 to G5[4]
. In addition, medicines taken and investigations and consultations carried out in the previous 12 months were reviewed.

A total of 1,791 (18%) patients were identified as hypertensive patients in a practice population of 10,413. Of these, 56% were aged 65 years or over.

The audit was carried out using searches on the practice computer. Quality standards and risk criteria were identified. The audit criteria were reviewed by the clinical commissioning group clinical lead and the local hospital’s consultant renal physician.

One of the diagnostic criteria for AKI in secondary care is for baseline creatinine to have increased by a minimum of 50%. Three patients were found to have significantly raised creatinine levels from their baseline result (taken as the first recorded serum creatinine for the patient). About 40% showed an abnormal urea and electrolytes result. Urinalysis had not been recorded routinely, although secondary care suggest proteinuria and haematuria are monitored. Around 65% of the patients in the sample were diabetic.

Out of the audit cohort, 75% had eGFR< 60ml/min/1.73m2 and 30% were taking high-risk medicines.

It is difficult to diagnose AKI in primary care but patients showing a significant drop in serum creatinine could be raised with the local hospital nephrology team for further advice and investigation, which could reduce the incidence of AKI and admission rates to hospital.

There were a surprising number of patients taking proton-pump inhibitors (PPIs). Long-term use of PPIs has been linked to CKD, with 32% patients in an American study seeing a decline in eGFR of >30%[5]
. Elderly patients taking PPIs are at twice the risk of entering hospital with AKI.

The audit did not include over-the-counter (OTC) non-steroidal anti-inflammatory drugs, which may be purchased by the patient and only 5% had received a medication review at the practice. This highlights a need to ensure all local practices and pharmacies are aware of the risk of AKI so they can educate patients and record OTC medicine use and to include community pharmacists in multidisciplinary discussions, plus the need for GP practice to refer patients for medication review at the pharmacy. There also needs to be more administrative support within practice to enable follow up diagnostics.

A joint approach of practice team, GPs and community pharmacy could lead to a major reduction in unplanned admission due to AKI.

Lindsey Fairbrother

Pharmacist independent prescriber

Good Life Pharmacy


Correspondence to:

Acknowledgments: Ruth Chambers, clinical chair, North Staffordshire and Stoke Clinical Commissioning Groups, and Andrew McClean, consultant renal physician, Royal Stoke University Hospital


[1]  Selby NM, Crowley L, Fluck RJ et al. Use of electronic results reporting to diagnose and monitor AKI in hospitalised patients. Clin J Am Soc Nephrol 2012;7(4):533–540. doi: 10.2215/CJN.08970911

[2] Think Kidneys. Communities at risk of developing acute kidney injury. 2015. Available at: (accessed 22 January 2017).

[3] Wang H, Muntner P, Chertow GM et al. Acute kidney injury and mortality in hospitalised patients. Am J Nephrol 2012;35(4):349–355. doi: 10.1159/000337487

[4] Derby Teaching Hospitals NHS Trust. AKI sick day rules. Available at: (accessed July 2017)

[5] Xie Y, Bowe B, Li T et al. Proton pump inhibitors and risk of incident CKD and progression to ESRD. J Am Soc Nephrol 2016;27(10):3153–3163. doi: 10.1681/ASN.2015121377

Last updated
Clinical Pharmacist, CP, September 2017, Vol 9, No 9;9(9):DOI:10.1211/PJ.2017.20203163