In a Los Angeles operating theatre, surgeons attempted something many urologists had long written off as impossible.
What unfolded there could reshape how doctors treat some of the most severe urinary disorders, giving one man back a basic function he had lost for years: the ability to pee.
A man who had run out of medical options
Oscar Larrainzar was 41 and exhausted by survival. A rare, aggressive cancer had forced surgeons to remove both of his kidneys and almost his entire bladder years earlier. Since then, his life revolved around dialysis sessions and medical appointments.
Without kidneys, his blood could not be filtered. Without a bladder, his body had no natural reservoir for urine. For seven years, machines did the work his organs could no longer perform.
For patients like Oscar, standard solutions are harsh. Surgeons can sometimes fashion a “new bladder” from a piece of intestine, or divert urine directly to an external bag on the abdomen. These techniques save lives, but they often come with recurrent infections, electrolyte problems, leaks, and a constant reminder of illness attached to the skin.
Oscar had already reached the end of what conventional surgery could offer. That is when specialists at the Ronald Reagan UCLA Medical Center decided to attempt something that had never been tried in a human patient: transplanting a donor bladder along with a kidney.
For years, bladder transplantation was considered too complex, too dangerous and too uncertain to even attempt in people.
A world-first double transplant in Los Angeles
On 4 May 2025, urologist and researcher Dr Nima Nassiri led an operation that lasted around eight hours. The team had spent four years preparing, testing surgical techniques in the lab, and carefully selecting the right candidate. Oscar’s unique situation made him suitable for a combined kidney-and-bladder transplant from the same deceased donor.
How the transplant was performed
The surgeons followed a precise sequence:
- First, they transplanted the donor kidney into Oscar’s pelvis and connected it to his blood vessels.
- Then, they implanted the donor bladder, positioning it deep in the pelvis.
- Finally, they connected the kidney’s ureter – the tube carrying urine – to the new bladder using a specially developed technique.
According to UCLA’s account of the procedure, the kidney began producing urine almost immediately after blood flow was restored. The transplanted bladder received and drained that urine without blockage.
➡️ 200 years on, DNA tests reveal the real culprit behind Napoleon’s disaster in Russia
➡️ I tried this creamy baked dish and it surprised me in the best way
➡️ 9 phrases seniors still use without realizing they offend younger generations
➡️ Archaeologists Are Astonished: A Mosaic Emerges Linking The History Of Rome And Ancient Egypt
➡️ 9 phrases self-centered people commonly use in everyday conversations, according to psychology
➡️ India watches nervously as its main rival moves to buy 50 new warships
Dialysis, which had defined the patient’s daily life for seven years, was stopped at the end of the surgery.
Beyond the skill of the surgeons, the hospital’s structure played a quiet but decisive role. At UCLA, kidney transplant services are integrated within the urology department. That close link, from pre-surgical assessment to long-term follow-up, meant every needed specialist – transplant surgeons, urologists, nephrologists, anaesthetists and rehabilitation staff – was already used to working as a single team.
Why bladder transplants are so difficult
On paper, transplanting a hollow organ like the bladder might seem simpler than replacing a heart or liver. In reality, the pelvis is a surgical minefield.
Blood vessels in this area branch and twist in tight spaces. Nerves control continence, sexual function and bowel movements. Any error can affect not just urinary control but multiple aspects of daily life.
For decades, those risks kept bladder transplant ideas in research papers and animal experiments, not operating rooms. Reconstruction using a patient’s own tissue, although imperfect, looked safer than asking the immune system to accept a foreign bladder.
Oscar’s case changed that calculation. He needed a new kidney anyway. Surgeons realised that if they could transplant both organs together, they might offer something closer to a natural urinary system than any reconstruction to date.
A promising step, but questions remain
Even with the apparent success of this first-in-human operation, specialists are cautious. One major unknown is long-term continence.
The transplanted bladder was not connected with its full set of nerves, so its ability to function like a normal organ over time is still uncertain.
Nerves tell a healthy bladder when to relax, when to contract, and when it is time to head to the toilet. Without these precise signals, patients may need catheters or scheduled voiding to keep the new organ draining safely.
There is also the constant issue of immunosuppression. Like all transplant recipients, Oscar must take drugs that dampen his immune system so it does not attack the donor kidney and bladder. Those medicines can have serious side effects:
- Higher risk of infections that a healthy immune system would usually control
- Metabolic issues such as diabetes, weight gain or high blood pressure
- Potential reactivation of dormant cancers or the appearance of new malignancies
For now, doctors see this procedure as a last-resort option for very specific patients, not a new standard offered widely. Clinical trials and longer follow-up are needed to judge how well transplanted bladders hold up after five, ten or more years.
Who could benefit from future bladder transplants?
If results remain positive, combined kidney-and-bladder transplants could matter for several groups of patients with no good alternatives:
| Patient situation | Current options | Potential role of bladder transplant |
|---|---|---|
| Severe bladder damage from cancer treatment | Intestinal “neobladder” or external urine bag | Aim for a more natural reservoir and urination |
| End-stage kidney disease plus bladder loss | Dialysis and urinary diversion | Restore both filtration and storage functions |
| Congenital malformations of the urinary tract | Multiple reconstructive surgeries in childhood | Future option if reconstructions fail |
Doctors stress that not every patient without a bladder would qualify. Good overall health, absence of uncontrolled cancer, and the ability to follow strict medication schedules would all influence eligibility.
Key medical concepts behind the story
For non-specialists, some of the terms around Oscar’s case can feel opaque. A few are worth unpacking.
Dialysis is a treatment that acts as an artificial kidney. Blood is filtered by a machine several times a week to remove toxins and excess fluid. It keeps people alive but ties them to rigid schedules and can cause fatigue, cramps and long-term cardiovascular problems.
Immunosuppressants are drugs taken after any transplant. They stop the body rejecting the donor organ but can make minor infections more serious. Patients must balance protection of the graft with a higher vulnerability to other diseases.
Continence refers to the ability to hold urine and release it at the right moment. It depends on the bladder, the urethral sphincter muscles and a complex network of nerves. A structurally perfect bladder is not enough if signalling and muscle control are disrupted.
What this could mean for future urology
Oscar’s case will likely influence both surgery and research. If longer follow-up confirms stable kidney function and an acceptable quality of life, more centres may start building similar multidisciplinary teams, combining transplant expertise and advanced pelvic surgery.
Researchers are already looking at how to improve such operations: mapping pelvic nerves more precisely, designing better ways to connect ureters, and perhaps combining donor bladders with elements of tissue engineering to reduce rejection risk.
For patients and families living with severe urinary tract damage, this story changes the conversation during medical consultations. Instead of discussing only diversions and external bags, doctors can talk about an emerging, still experimental option that aims to restore something closer to a normal urinary cycle.
That does not mean every hospital will start offering bladder transplants, or that the risks will vanish. But the barrier of “this has never been done in humans” has fallen. For one man in Los Angeles, that shift translated into an experience most people take for granted: going to the bathroom and finally, after seven years, being able to pass urine again.
Originally posted 2026-02-09 23:24:32.