Chronic Kidney Disease: Screening and Diagnosis (Guidelines)

Patients at risk:

Diabetes
Hypertension
Acute kidney injury (minor patients for CKD for at least 3 years after Acute Kidney Injury (AKI), even if serum creatinine returned to baseline)
Cardiovascular disease
Structural renal tract disease, recurrent renal calculi, prostatic hypertrophy
Multisystem disease with potential kidney involvement - e.g. Systemic lupus erythematosus (SLE)
Family history of End stage renal disease (ESRD) (GFR category CKD5) or hereditary kidney disease
Opportunistic detection of haematuria
Nephrotoxic drugs - lithium, NSAIDs, ACEI, ARBs, ciclosporin, tacrolimus

Proteinuria

Do not use reagent sticks to diagnose proteinuria
Urine albumin:creatinine ratio (ACR) is more sensitive than urine protein:creatinine ratio at low levels of proteinuria
ACR will be used for screening. A normal result is ACR < 3 mg/mmol
Proteinuria is not an indication for urine culture in the absence of symptoms of urinary tract infection (UTI)
In patients with symptomatic UTI the test for proteinuria should be delayed until after UTI resolved
If urine ACR > 70 mg/mmol, a protein:creatinine ratio will be checked

When testing for haematuria use reagent strips rather than urine microscopy.
Presence of haematuria in 2 out of 3 reagent strip tests confirms persistent invisible haematuria
Persistent invisible haematuria with or without proteinuria should prompt investigation for urological malignancy in those aged over 50
Persistent invisible haematuria with proteinuria should be followed up annually with repeat testing for haematuria, ACR, GFR and BP as long as haematuria persists.

Frequency for monitoring of GFR (number of times per year, by GFR and ACR category for people with or at risk of CKD

GFR Category	ACR Categories (mg/mmol) A1 <3 normal to mildly increased	ACR Categories (mg/mmol) A2 3-30 moderately increased	ACR Categories (mg/mmol) A3 >30 severly increased
G1 >90 normal and high	<1	1	>1
G2 60-89 mild reduction related to normal range for young adult	<1	1	>1
G3a 45-59 mild-moderate reduction	1	1	2
G3b 30-44 moderate-severe reduction	<2	2	>2
G4 15-29 severe reduction	2	2	3
G5 <15 kidney failure	4	>4	>4

This should be tailored according to:

The underlying cause of CKD
Past patterns of eGFR and ACR (but be aware CKD progression is often non linear)
Co-morbidities especially heart failure
Changes to treatment (such as ACEI/ARBs, NSAIDs, diuretics)

Abbreviation	Meaning
CKD	Chronic kidney disease
eGFR	Estimated gomerular filtration rate
ACR	Urine albumin to creatinine ratio
AKI	Acute kidney injury
ACEI	Angiotensin converting enzyme inhibitors
NSAIDs	Nonsteroidal anti-inflammatory drugs
ARBs	Angiotensin II receptor blockers

Last reviewed: 30/11/2023

Next review date: 30/11/2026

Author(s): Renal Department .

Version: 1

Approved By: TAM subgroup of ADTC

Reviewer name(s): Dr N Joss, Consultant Nephrologist.

Document Id: TAM363