Proteinuria

Healthy individuals pass frothy or bubbly urine every now and then. This may be caused by the speed and force that urine is passed out and the proteins that occasionally come with it. This transitory proteinuria (“protein in urine”), also sometimes called albuminuria, is normal and can be found in a number of benign conditions such as fever and pregnancy. However, persistence can be an early warning sign of impending or ongoing kidney disease. Medically defined, proteinuria is excretion of more than 150 mg daily of protein in the urine and warrants further investigation. 

Types and causes of proteinuria 

Proteinuria can be divided into transient or temporary and persistent. The former does not necessarily require more comprehensive evaluation, and the proteinuria resolves once the inciting event is addressed; the latter is pathological proteinuria, and patients need thorough medical evaluation to manage the cause and prevent further deterioration. 

Symptoms Commonly Associated with Proteinuria 

Proteinuria is usually asymptomatic in the early stages, but it can still be identified through urine analysis. As the disease becomes more serious, more symptoms may appear: 

• Urine is persistently foamy due to high protein content 
• Edema of the hands, feet, abdomen, and face 
• Frequent urination 
• Shortness of breath 
• Eyes that are puffy especially in the morning 
• Loss of appetite 
• Fatigue 
• Muscle pain especially at night 
• Chronic low-grade fevers 
• Unexplained weight loss 

Proteinuria is a warning sign for kidney disease and other chronic diseases. If the condition persists, it can lead to acute renal failure, fluid accumulation in the lungs, and an increased risk of cardiovascular disease, bacterial infection, and arterial or venous embolism. 

High-risk group for proteinuria 

 The following conditions predispose people to proteinuria: 

• Hypertension 
• People with type 1 and type 2 diabetes 
• Obesity 
• Primary nephropathy (kidney dysfunction) 

• Aged 65 and above 
• Family history of kidney disease 
• Pregnancy toxemia (hypertension due to pregnancy) 
• Individuals with autoimmune connective tissue disorders such as SLE, rheumatoid arthritis (RA) and Sjögren’s disease 

Diagnostic methods for proteinuria 

The following are different types of proteinuria based on laboratory findings:  

Treatment of proteinuria 

Since proteinuria is interrelated with kidney disease and other chronic medical conditions, the treatment is mainly directed at the root causes of persistent proteinuria enumerated in the table above. For chronic medical conditions such as diabetes, hypertension and obesity, lifestyle modification (i.e. diet, exercise, sleep/rest, smoking cessation) coupled with medication and regular monitoring are the mainstays of management. Prior awareness of nephrotoxic effects of different medications especially common ones like (non-steroidal anti-inflammatory drugs) NSAIDs, beta-lactam antibiotics (e.g. co-amoxiclav) and quinolones (e.g. levofloxacin) can prevent kidney damage. And malignancies and auto-immune connective tissue disorders can be discussed with medical experts and family members for optimum approach to multi-modal management.  

Prevention of proteinuria 

In Hong Kong, two studies, namely, the Screening for Hong Kong Asymptomatic Renal Population and Evaluation program (The SHARE program 2003) and Relatives in silent kidney disease screening study in Hong (The RISKS study 2009), emphasized that: (1) simple screening methods such as urinalysis and blood pressure measurement, and (2) screening asymptomatic first-degree relatives of patients with chronic kidney disease (CKD), are means by which the populace can be proactively advised of their risks of developing kidney disease even without overt symptoms.   

OT&P Medical Advice 

When it comes to kidney disease, the earliest awareness through personal or family history and professional medical advice provides the greatest benefit for at-risk individuals who can start with a simple urine test. At OT&P Healthcare, we aim to help you understand your health better. We offer a range of services, including a general practice clinic. Contact us today to book an appointment.

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