Kidney cysts can be divided into simple and complex cysts.
They are usually asymptomatic, except when complicated by hemorrhage, infection, or rupture.
Occasionally, these lead to the development of complex cysts with:
- calcification
- demarcation irregularities
- and multilobularity which become more suspicious for cancer
Complex cysts are associated with cancer and may be caused by genetic or acquired cystic diseases of the kidney.
Inherited forms of cystic disease, particularly autosomal dominant polycystic kidney disease, demonstrate the role of genetics in the formation of cysts. Recent evidence, though not entirely conclusive, suggests additional associations with hypertension, kidney size, and renal function.
Risk factors suggested in the formation of simple cysts are:
- raised serum creatinine
- hypertension
- and smoking
Clinically, patients may present with flank pain, abdominal pain or hematuria. A large cyst may cause obstructive symptoms and give rise to complications such as rupture or infection.
Thus, in simple terms, genetics play the biggest role in kidney cyst formation. Other risk factors such as smoking, poor kidney function, and hypertension have been suggested, so it may be wise to minimise these risk factors.
If you suspect a possible cyst, do consider imaging tests, such as an ultrasound, a computerized tomography (CT) scan and magnetic resonance imaging (MRI), which are often used to investigate simple kidney cysts.
Best regards
Dr Quah
