Free Radicals - Michael Brooks [52]
An antibiotic-resistant strain of Staphylococcus had been found in one of the hospital’s wards. The managers, anxious to know whether the hospital needed to invest millions of dollars in new antibiotics, had set up a quarantine for medical staff who had been in the area where the outbreak occurred. Their throats were being regularly swabbed for the new strain to see whether they were carriers. The burden of analysing these extra samples fell on the microbiology lab. Dr Marshall’s unimpressive project was now a low priority.
In the months leading up to the outbreak, the results of Marshall’s experiments had always proved disappointing for the microbiology staff. There was never anything to see, and the samples were thrown away after forty-eight hours. But now the lab staff were under pressure. And that was how the samples from patient number 37, a middle-aged man with a history of duodenal ulcers, came to be forgotten when they were due for inspection one Saturday morning.
Patient 37 had undergone his endoscopy on the Thursday before Good Friday. As usual, Marshall had rushed the stomach lining biopsies to the microbiology lab as soon as he could, and the hospital’s technicians immersed them in the prescribed nutrient solution and put the samples into the tightly controlled temperature and humidity conditions of the incubator. And, thanks to the holiday and the extra workload, there they remained, untouched and uninspected, until the Tuesday after Easter. And five days was plenty of time for the spiral bacteria to grow. At last, Marshall had a culture.
Such tales of serendipity are common in science. As we have seen, so are little indiscretions with data: the process of science is just too messy for these to be avoided. That’s why Barry Marshall, months before he got to the anarchy that make him the prime mover in this chapter, had to perform a little anarchy on his data. It was hardly anything, but, given what we have seen so far, interesting. No one now disputes the discovery, but it would have been a little less convincing at the time had he not bent the rules by just a few degrees.
The procedure for analysing the data from the patients was exemplary. Rose Rendell, a statistician, was appointed to oversee the analysis. Marshall, Robin Warren and John Pearman, the head of the microbiology lab, sent their results to the statistician directly, rather than giving each other the chance to influence anything. In June, the endoscopists finally sent Marshall their reports of whether they had seen lesions (ulcers) in the stomach walls of the patients. Marshall forwarded the reports to Rendell. By September, Rendell had put everything together and sent it to him. The initial results were exciting.
Of the twenty-two patients with gastric ulcers, eighteen were infected with the spiral bacteria. And, Marshall was thrilled to find, there was an explanation for the other four. All the patients had filled out a questionnaire about their medical health. According to the answers, the four patients with a gastric ulcer but no spiral bacteria were all taking anti-inflammatory drugs such as ibuprofen. These are known to cause stomach problems, including ulcers. Even more satisfying was the fact that nigh on 100 per cent of the patients with duodenal ulcers – twelve out of thirteen – tested positive for this new bacterium. It seemed extraordinary, but the explanation was almost perfect.
Almost. Experimental data don’t always play ball, as we have seen. The one duodenal ulcer that was not associated with a spiral bacterium infection could not have been due to anti-inflammatories. Entry to the duodenum is controlled by a gateway, the pyloric sphincter, and there was no way the drugs could get into the duodenum in high enough concentrations to cause an ulcer.
Marshall was worried that he may have miscounted the number of duodenal ulcers: perhaps the one