German medical authorities are calling for an extensive overhaul of the country's organ transplant programme after transplant centres across Germany were placed under criminal investigation over allegations that they had systematically manipulated donor waiting lists.

Scores of patients are believed to have been given priority access to donor organs after doctors falsified the severity of their illnesses to ensure they received treatment ahead of other patients in Europe.

The revelations have led to accusations of widespread corruption and dishonesty in the system, and shattered public trust. Since the scandal emerged last year as a handful of cases that were initially believed to be isolated incidents, the number of Germans willing to donate organs has plummeted.

Post-death donations have dropped by between 20% and 40%, according to the German foundation for organ transplantation (DSO), which said the public's faith had been "massively shaken".

Investigations across the country have revealed that in at least four clinics, patient data was distorted or falsified in order to improve patients' chances of getting an organ. At least 107 cases of obvious manipulation have come to light so far.

At one clinic in Munich, in southern Germany, doctors were accused of "active manipulation" of data after investigators discovered cases in which patients' blood samples were mixed with urine to make them appear sicker than they were. Urine in the blood is an indication that internal organs are no longer functioning properly.

In two further cases, blood samples were submitted from a person who had never even been a patient at the clinic.

Clinics have come under investigation in Göttingen, Regensburg, Munich and Leipzig. All of them are university teaching hospitals with hitherto excellent reputations. Experts blamed the growing competition between clinics, which are increasingly coming under pressure to boost revenue. The worldwide shortage of organ donors exacerbates the problem.

Senior doctors and transplant surgeons across the four clinics have been suspended pending further investigations.

"There are too many transplant centres in Germany and too few organs," said Eugen Brysch, the head of Germany's foundation for patient protection.

A doctor in Göttingen reported to have had written into his contract that he would receive bonus payments for every liver he was able to transplant, a system of rewards already deeply criticised by Germany's medical authorities.

In other cases, doctors are believed to have come under pressure to help increase the prestige of the institutions where they worked. The more successful transplants a hospital carries out, the more its reputation is boosted and the more funding it is likely to receive.

At Leipzig's University Clinic, the latest hospital to be investigated, surgeons are accused of blocking the investigation by Germany's general medical council after claiming to have mislaid patients' notes, including details of who was receiving dialysis treatment. The documents finally came to light this month, allegedly revealing a similar pattern of data manipulation.

The medical council (Arztekammer), has identified at least 38 cases of manipulation in Leipzig, allegedly involving distorted applications to Eurotransplant, the European organ transplant centre based in Leiden, the Netherlands, claiming that patients with liver disease had had their blood cleansed. This improves a patient's chance of receiving a donor liver because there is a high chance that as well as the liver, their kidneys will fail.

Wolfgang Fleig, director of the medical board of the Leipzig clinic, said he was shocked by the allegations, but said it was still unclear whether bribery had been involved. "I cannot put my hand in the fire and say that no money changed hands over this," he said.

Since the allegations came to light, Eurotransplant has tightened its application procedure, requiring doctors to give more detailed information about patients, such as records of dialysis treatment, rather than just a ticked box.

The president of the medical council, Frank Ulrich Montgomery, promised that all 47 transplantation centres in Germany were now being thoroughly inspected for any irregularities and not just in cases where wrongdoing was suspected. "The sad message is … that obviously more centres have been involved in manipulation than initially thought," he said, adding he expected more cases to come to light, but that procedures had been considerably tightened.

Eurotransplant receives donor organs from around Europe, and redistributes them according to various criteria, including urgency and chance of success.

"Only with the maximum amount of transparency and better controls are we going to be able to bring trust back into the system," said Montgomery. Politicians from across the divide have called for tighter state regulation of the organ donor system.

Germany's parliament amended the organ transplant law last year to address the desperate shortage of donor organs. Now everyone over the age of 16 is asked whether they are prepared to be a donor. Around 12,000 people are currently waiting for a transplant in Germany, according to DSO. But donor readiness remains low. There are only 15.8 donations for every million inhabitants, compared with 32 per million in Spain.

Germany's health minister, Daniel Bahr, defended Germany's transplant system, saying: "Germany has some of the strictest rules governing the transfer of organs."

Supply and demand

Organ transplants are miraculous and save lives, but the difficulty obtaining enough organs to supply the demand generates regular scandals.

The Leipzig affair would appear unprecedented. It is hard to imagine the motivation of doctors who would falsify the paperwork to make their patients appear sicker than others to jump the queue. Questions will be asked about the ambitions and reimbursement of the clinics and doctors involved.

But patients – sometimes helped by their doctors – do go to extreme lengths to obtain the organs they need in a global market with insufficient supply.

The shortfalls have become worse as transplantation has become more routine and, in countries such as Britain, seatbelt legislation has cut the number of healthy young adults dying prematurely in motor accidents.

Reports of human organs for sale have been common across the world. Police in South Africa and Brazil uncovered an international organ trafficking syndicate.

In the case of kidneys, as humans can function with one fewer than most of us are born with, respectable doctors and ethicists have argued the case for allowing people to sell one to relieve their poverty. Parts of the liver (which can regenerate) and the corneas from eyes are also saleable.

But the World Health Organisation fears donors in countries without regulatory frameworks are at risk of coercion, exploitation and physical harm.

Not all donors have volunteered. A major scandal broke in China when it was discovered that most of the organs in 12,000 kidney and liver transplants carried out in 2005 came from executed prisoners.

Some of them went to people with money in need of a transplant who flew to China from 19 different countries. © Guardian News and Media 2013