Only few of the 165,000 people with strokes, as registered in the index per year as stroke patients, die immediately in Germany. But the prospects after a stroke are not exactly bright: Four out of ten patients die within one year, most of them within the first four weeks after the stroke. And 15 percent of the survivors are handicapped so badly, that they end up in a nursing home.
From an immunological point of view, strokes affect the lung
It is by far not only the brain, respectively the closed vessels, causing the death: "Thirty percent of those dying within the first 30 days after a stroke, die from pneumonia", says Andreas Meisel, neurologist at the Charité in Berlin. So far, physicians have explained this basically known problem intuitively with that tendency of stroke patients to aspirate. This could be the basis for aspiration pneumonia, thus causing a fatal outcome. "Basically not wrong", thinks Meisel, who held a lecture on this topic at the "Deutsche Ärztekongress" (German Physicians' Congress) in Berlin. Not wrong, but grossly fragmentary. At least at the model "mouse", Meisel and his colleagues showed, that animals, after an acute closure of brain artery, got aspiration pneumonia a lot faster than healthy animals. In some cases a few aspirated germs were enough, while with healthy animals ten thousands were necessary to cause any pneumonia similar situation at all. "It is obvious that there has to be an stroke-specific decrease in immune competence, not showing so easily in other diseases", as Meisel interprets the observations.
The problem seems to be the monocytes
But does this apply to humans as well? In the opinion of the Berlin physicians – yes. On that account they made a study, first results are available now. In this Pantheris study, they were able to verify very similar changes in the immune system of eighty stroke patients, like they observed in the mice. Within a short time, a distinct lymphopenia developed, in particular a malfunction of the monocytes. Monocytes are those cells having a specific defense function in antigen presentation as well as being responsible for the phagocytosis, being non-specific as tissue macrophages.
But really exciting are the clinical results of the Pantheris study. They did not just look at the cells, but made real medical science. After randomization, forty patients at a time received either the usual standard treatment after a stroke in the Stroke Units of the Berlin Charité or an additional antibiotics prophylaxis, in this case 400 milligrams Moxifloxazin per day. Of course, the patients in the control group received antibiotics as well, as soon as infections developed, but not beforehand as a prophylaxis.
Does the protection from pneumonia also protect from death?
The result was that impressive, that a phase II study will follow the Pantheris study, directly followed by a genuine study phase III. Within the first eleven days after the stroke, every fifth patient of the placebo-group developed a pneumonia, but it was two thirds less in the group of patients taking Moxifloxazin. Whether the patients developed a pneumonia or not, was the essential factor regarding the death rate: "55 percent of the patients developing an early pneumonia, died within the first six months", as Meisel quoted in Berlin. The death rate of patients not suffering from pneumonia was only at about twenty percent. Statistically this difference is highly significant. Despite the promising results, the people in Berlin do not want to go out on a limb just yet. Not before the results of the phase III study will be available. "What we are trying here, is not yet a medical standard at all", emphasizes Meisel.