A Small Kidney, A Big Lesson

By Dr Kamal ‘Akl, Consultant Paediatrician & Paediatric Nephrologist

When six-month-old Sanad was born with a cleft palate, his doctors suspected a possible link to other conditions—especially involving the heart or kidneys.

A visit to the cardiologist confirmed Sanad’s heart was healthy and he was cleared for general anaesthesia.
But a follow-up ultrasound ordered by the nephrologist revealed something unexpected: Sanad’s right kidney was smaller than normal.

What Does That Mean?
Understandably concerned, Sanad’s mother asked the questions on every parent’s mind.
Mother: What could be the cause of a small kidney?
Doctor: One common cause is something called “urinary reflux” — when urine flows backwards from the bladder toward the kidneys. If this happens early in fetal development, it can interfere with kidney formation and result in a smaller, less functional kidney.
Mother (tearfully): Will this cause kidney failure?
Doctor: Not necessarily. If the other kidney is healthy and functioning well, there’s no need to worry.
Mother: How can we be sure the other kidney is normal?
Doctor: We check for reflux. A radiologist introduces a small tube through the urethra, then injects contrast dye into the bladder. If reflux is present, it shows on the scan. If there’s no reflux and kidney function is normal, that’s very reassuring.

What Happens to the Small Kidney?
Mother: Will it get worse?
Doctor: It might stay the same or gradually shrink over time. That’s why regular monitoring is essential.
Mother: How do we protect the healthy kidney?
Doctor: Sanad will need regular check-ups—an annual ultrasound to monitor growth, blood pressure checks and urine tests every six months.

To explain further, the doctor offers a simple analogy:
“Imagine a carriage with 10 flour sacks pulled by two horses. If one horse falls ill, the other must carry the full load alone. It might manage for a while, but without help or a lighter burden, it’ll eventually tire out.”

Easing the Load
To keep the healthy kidney strong, the doctor recommends a few simple lifestyle adjustments:
Cut down on salt and red meat, which strain the kidneys. Opt for fish and poultry instead
Avoid unnecessary medications, as some can be harmful to kidney health
Act quickly if Sanad gets dehydrated, especially during childhood illnesses like gastroenteritis

And most importantly: “There’s no need to be afraid,” the doctor reassures. “Many people live perfectly healthy lives with one small kidney—or even just one kidney—without ever knowing it. What matters is care, awareness, and regular follow-up.”

You can contact Dr Kamal ‘Akl at [email protected]