A version of this story was published with The Sunday Times (UK).

LONDON -- Two years ago in a conference room in the Randolph hotel in Oxford, England, Henrik Thomsen gave his inside account of a medical "nightmare." In a presentation to about 30 colleagues, Thomsen, one of Europe's leading radiologists, revealed how patients treated at his Copenhagen University hospital had subsequently contracted a rare and potentially fatal disease.

Thomsen and other doctors were baffled about why 20 kidney patients who had been given routine scans were afflicted by a disorder — nephrogenic systemic fibrosis (NSF) — in which the skin gradually swells, thickens and tightens. Some sufferers were confined to wheelchairs. At least one died. There was no known cure.

Then, in March 2006, came a breakthrough. It was confirmed that all those who had fallen ill with NSF had been given the same drug in advance of a magnetic resonance imaging (MRI) scan.

That drug, Omniscan, was used to enhance the images produced by the scan. The product was sold around the world and was manufactured by GE Healthcare, a subsidiary of General Electric, one of the world's largest corporations.

Thomsen's presentation lasted no more than 15 minutes, with the final slide reading: "I hope none of you meets a similar medical hurricane."

The 56-year-old radiologist, now director of diagnostic sciences at the University of Copenhagen, is part of a small group of clinicians credited with alerting patients and regulators to the potential risks of Omniscan for renal patients. The UK Medicines and Healthcare Products Regulatory Agency this weekend said there had been 20 reports in the UK of NSF after patients were given Omniscan. Five of the patients died.

Last month, European medical regulators recommended that anybody who needs an MRI scan should be given a check to ensure their kidneys are healthy if they are to be given Omniscan or two other similar products. In the U.S., the Food and Drug Administration (FDA) is reviewing whether to further restrict the drugs.

Thomsen, however, now refuses to speak anywhere in England on the possible risks of Omniscan. The reason is that he faces another kind of storm: GE Healthcare is suing him for libel in the UK High Court.

The company claims his presentation in Oxford — entitled "Management Aspects of NSF" — was highly defamatory. GE has already racked up costs of more than £380,000 (about $615,000) pursuing the respected academic, who has authored or co-authored nearly 400 papers and delivered countless presentations to his peers. Thomsen will have to pay GE's costs if he loses the case.

In recent weeks, The Sunday Times has highlighted how Britain's draconian libel laws are being used to intimidate critics of the rich and the powerful into silence. In a number of cases, plaintiffs and claimants have little apparent connection with the UK. Campaign groups have warned that vital scientific and medical work is being threatened because of the threat of libel actions.

Thomsen, who was in London last week meeting his lawyers at the firm Carter Ruck, has no doubt about the driving force behind his case. "I believe that the lawsuit is an attempt to silence me," he said.

How GE Acquired Omniscan

In October 2003, General Electric, one of the most watched companies on Wall Street, made a successful bid of about $10 billion for Amersham, the British health care company that had been privatized by former Prime Minister Margaret Thatcher.

GE has a finger in many lines of business, from manufacturing light bulbs to insurance sales, but this appeared a particularly good fit. GE Medical Systems already made scanning equipment, and Amersham made the products used to enhance medical imaging. The combined business — GE Healthcare — had its headquarters in Buckinghamshire in southeast England and was expected to generate about $13 billion annually, representing about 10 percent of GE's revenue at that time.

One of the imaging products was Omniscan, which is among a small group of drugs administered to patients before an MRI scan. Called contrast agents, the drugs enhance the differences between fluids and structures in the body when they appear on scans, making diagnosis easier.

To date, Omniscan has sold more than 48 million doses worldwide. Such products sell for about $30 a dose.

There was, however, a problem. A small number of kidney patients injected with Omniscan and other products were falling ill with NSF, a horrific disease that first attacks the skin and can then attack organs. Those with healthy kidneys were unaffected; the product has been safe for more than 99 percent of patients.

NSF was first identified in America in 1997, more than five years after the contrast agents were introduced, and doctors were initially mystified about the cause.

One victim, Celeste Castillo Lee, from North Carolina, who testified earlier this month at an FDA hearing, described how the disease migrated through her body, causing agony. "Seventy-five percent of us are in wheelchairs," she said. "It's actually a torture." She said swelling, which started in her ankles, moved inexorably through her limbs and then attacked her insides. Her bones, she said, felt like they were in a vise.

In British hospitals, doctors were also finding cases of the new and strange condition. Giles Roditi, a consultant radiologist at Glasgow Royal Infirmary, said his hospital had 16 cases of NSF in renal patients. So what was causing it? In early 2006, Thomsen turned clinical detective to try to answer this question. After he was told that every kidney patient at his hospital who was diagnosed with the disease had been given a drug for a MRI scan, he and his colleagues alerted the medical authorities, then embarked on a review of all known cases of NSF.

Every patient out of the 150 cases he found had been given a contrast agent for an MRI. About 90 percent of the patients had been given Omniscan. It was not proof that the drug caused NSF, but it was enough evidence for Thomsen never to give it again to any kidney patient.

Omniscan is one of several competing MRI agents that contain the metal gadolinium, which is potentially toxic. The metal is chemically protected in its various drug forms and is quickly flushed out of the body by patients with healthy kidneys. However, regulators believe the chemical structure of Omniscan, and another similarly constructed product, makes them less stable and potentially dangerous for those suffering from renal problems.

The Danish Medicines Agency was the first to sound the alarm, highlighting 25 cases linked to Omniscan in a notice in May 2006.

Many of the Danish patients filed claims with a Danish government insurance agency, which pays benefits if it determines that a drug was a likely cause of inquiry or death. In one of those cases, involving a 55-year-old woman who died from a lung embolism in 2003, the insurance agency concluded the side effects from Omniscan had "caused" her immobilization, which, in turn, "caused" her deadly embolism. GE declined to comment on this case last week.

In June 2007, the Commission on Human Medicines in the UK advised doctors not to use Omniscan in patients with severe renal problems along with two other products, Magnevist, manufactured by Bayer HealthCare, and Optimark, produced by Covidien. It recommended that other products containing gadolinium should not be used for kidney patients unless essential.

GE Healthcare reacted promptly to concerns over its product, but the company objects to some of Thomsen's work and the decisions by the European regulators. While it does not deny an association between its product and NSF, the company said it was unfair to classify Omniscan as particularly risky. GE insists that a causal link to NSF has "not been established" and that a reporting bias (PDF) may account for the high number of NSF cases linked to its product.

GE's arguments helped sway regulators in the U.S., the biggest market for Omniscan. The FDA has warned doctors of an association between contrast agents and NSF, but until recently the agency said data was too limited to classify some of the products as more risky than others. So far, the FDA has stopped short of recommending that doctors stop using any of these products in kidney patients. FDA's staff has been revisting the evidence and this month said it now believes that Omniscan, Optimark and Magnevist pose higher risks. On Dec. 8, a majority of members on an FDA advisory panel went a step further, recommending that Omniscan and Optimark should not be given to patients with severe kidney disease.

The regulatory action represents a victory of sorts for Thomsen and may mean less chance of kidney patients suffering from this disease in the future. But his mind is now on another looming battle with GE in the High Court.

Academics and radiologists who attended Thomsen's presentation say it is "ludicrous" that he faces a potentially ruinous legal action and are writing letters of support. His PowerPoint presentation is summarized in one GE legal filing and appears to be an objective analysis of the association between Omniscan and NSF.

GE Healthcare said this weekend the presentation was defamatory because it accused the company of suppressing information and marketing its product when it was aware of possible problems. Last week, however, a spokeswoman was unable to highlight any part of Thomsen's presentation in which this allegation was made. GE’s lawsuit says the defamation may have been "by way of innuendo."

Carter Ruck, which is defending Thomsen on a no-win-no-fee basis, says the case should be dismissed because the material is clearly not defamatory.

GE Healthcare is also suing over an article that appeared under Thomsen's name in Imaging Management, a medical journal published in Belgium. The article referred to rumors that the company had been warned about possible problems with its product. Thomsen says he did not "write or publish" the words that are the subject of the complaint and that they were written by a journalist. He denies libel.

The GE Healthcare spokeswoman said the company supports scientific debate and sued Thomsen only as a "last resort." She said GE always reacted quickly and in the best interests of patients to any possible side effects of Omniscan and reiterated that the product was still safe to use for the vast majority of patients.

The Debate: Defamation or Free Speech?

Thomsen’s case, however, is the latest example of the UK courts being used against scientists who scrutinize drugs and treatments. Simon Singh, a science writer, is being sued by the British Chiropractic Association for describing some of their treatments as "bogus."

Another target is Peter Wilmshurt, a consultant cardiologist at Shrewsbury hospital in central England. He is being sued by an American company, NMT Medical, after he questioned the effectiveness of a new heart implant device.

A Libel Reform Campaign is now urging capped damages, stricter controls on costs and a stronger public interest defence. Index on Censorship, a London-based free-speech group, is among a number of organizations supporting the campaign. Thomsen's case "appears to be yet another shocking example for multinational corporations going after academics and scientists working in the public interest," said John Kampfner, the group’s chief executive.

Sir Ken Macdonald, the country’s former top prosecutor, has already called for reform. "The idea that we are becoming an international haven for people to attack scientists is something that we should not be proud of," he said.

The House of Common's culture, media and sport committee is compiling a report which is expecting to recommend change in the country's libel laws. UK Justice Secretary Jack Straw, the equivalent of the U.S. attorney general, has already announced a review.

Colin Blakemore, professor of neuroscience at Oxford University and an adviser to Sense about Science, which promotes the use of good science in public debates, said any review should ensure the libel courts are never used as forum for assessing the risks of a treatment. "The risk is that the party with the most money will always win in what should be a dispassionate assessment of evidence," he said.

GE, along with other manufacturers of contrast agents, now faces action in the American courts over its drug. A legal brief filed in federal court in Cleveland by lawyers acting for nearly 500 plaintiffs says Omniscan was "routinely administered to kidney patients for years without warnings."

The litigation suggests the debate over exact side effects of Omniscan and other products is likely to continue for many years. Thomsen's concern is about medical researchers who will need to highlight possible risks from drugs in the future. He says it is essential that they are not cowed by the prospect of appearing before the libel courts in London. "It's dangerous for the patient if we can't frankly exchange views," he said.