Medical presentation of kidney disease (7 syndromes)

Medical presentation of kidney disease (7 syndromes)

This article is largely for health professionals.

Key Points

Kidney disease can present in 7 ways (ie. 7 different renal presentation syndromes):

1. AKI or AKI on CKD
2. CKD
3. Proteinuria/nephrotic syndrome
4. Micro/macrohaematuria
5. Hypertension
6. Nephritic syndrome
7. Urological/transplant presentation.

Note. Some patients present with 2 or or more of them – e.g. IgA nephropathy can present with CKD and nephrotic syndrome.

How are these syndromes discovered?

These syndromes can be discovered in different ways, including:

1. Screening of asymptomatic individuals (often by chance)
2. Symptoms and signs resulting from renal dysfunction (in the 7 ways described below)
3. Symptoms and signs of an underlying disease (often systemic; which has resulted in renal dysfunction).

In many cases symptoms are nonspecific or not apparent, and detection of renal disease relies on:

1. A combination of clinical assessment (history and examination), and ..
2. Three simple investigations:
   • Estimation of renal function (with blood creatinine/GFR)
   • Urinary ACR (protein)
   • Renal ultrasound.

7 renal presentation syndromes

1. Acute Kidney Injury (AKI; or AKI on CKD)

The presentation of AKI is dominated by its underlying cause (e.g. sepsis or post-operative).

Note 1. Patients with AKI can be hypovolaemic (‘dry’ or dehydrated), hypervolaemic (‘wet’ or fluid overloaded) or euvolaemic (fluid state normal)
Note 2. Patients with AKI can be oliguric (less urine), polyuric (more urine) or have a normal urine output. Oliguria means passing less than 400 ml/day. Oligo-anuria means less than 200 ml/day
Note 3. Anuria (no urine) is very rare. It has three causes: obstruction (commonest), acute severe glomerulonephritis/vasculitis and vascular catastrophe (e.g. AAA affecting renal arteries)
Note 4. AKI can rarely occur as a ‘pulmonary renal syndrome’ (PRS), i.e. a severe AKI with upper or lower airway disease (typically epistaxis or haemoptysis = nose bleed or coughing up blood).

2. Chronic kidney disease (CKD)

This is usually asymptomatic in its early stages. In the later stages there may be symptoms (e.g. of fluid overload, itching).

3. Proteinuria/nephrotic syndrome

This may be asymptomatic; but latter comprises oedema, proteinuria, and hypoalbuminaemia.

4. Microhaematuria/macrohaematuria

For the latter, urological disease, especially cancer, should be excluded first.

5. Hypertension

Accelerated hypertension (hypertensive emergency) is especially likely to have an underlying renal cause.
Note. Essential hypertension does not cause renal disease.

6. Nephritic syndrome

This means the combination of haematuria, elevated blood pressure, decreased urine output, and oedema. The major underlying pathology is inflammation of the glomerulus that results in nephritic syndrome. It is a rather old-fashioned term. In the modern era, we describe what we see (e.g. an ‘AKI with microscopic haematuria and fluid overload’). It was the classical presentation of post-infectious glomerulonephritis.

7. Urological presentation

E.g. recurrent UTIs; disturbance in urination; stones; loin/kidney pain/mass.

Rarer presentations

• Disturbance in mineral levels – e.g. hypokalaemia (low potassium level) in renal tubular acidosis (RTA), or Bartter Syndrome
• Renal disease identified incidentally with imaging. Advances in imaging technology combined with their widespread use have increased the number of incidental renal abnormalities identified. Many of these are anatomical abnormalities which are of little consequence, such as duplex ureters and isolated renal cysts. But significant pathology is sometimes found incidentally, such as polycystic kidneys, renal tumours, and asymmetrical kidneys
• Family screening for renal disease. Patients with a family history of inherited renal disease may also be identified with early, asymptomatic renal disease as a result of screening. The most common example is autosomal dominant polycystic kidney disease (PKD), which may be reliably identified by ultrasound from the age of 20 years onwards.
• Genetic screening for renal disease. The identification of genes for inherited renal diseases such as PKD, tuberous sclerosis, von Hippel-Lindau disease, Alport’s syndrome, and congenital nephrotic syndrome, raises the possibility of future antenatal screening and early detection of these diseases long before they become clinically manifest.

General points

1. All of the syndromes above can be asymptomatic – i.e. the patient is unaware of the problem
2. ‘Uraemia’, as a presentation is now rare. It is an old-fashioned term (a bit like nephritic syndrome). It means the features of severe CKD, with severe chronic depression of glomerular filtration rate. This manifests with some or all of: anorexia, nausea, vomiting, fatigue, weakness, pruritus, breathlessness, bleeding tendency, apathy and loss of mental concentration, and muscle twitching and cramps.

Summary

We have described the medical presentation of kidney disease. It can present in 7 main ways (syndromes). Some patients have more than one syndrome. We hope it has been helpful.

Last Reviewed on 19 June 2024