ATHEROSCLEROSIS AS CONSEQUENCE OF CHRONIC INFECTION BY CHLAMYDIA-PNEUMONIAE

In the last years several new data allow a controversial but convincin g interpretation of the pathogenesis of atherosclerosis (arteriosclero sis). Atherosclerosis can be apparently the result of ultrachronic per sistent infection by Chlamydia pneumoniae and not the result of differ ent risk factors. The main arguments for the chlamydial genesis are: 1 . Correlation of coronary heart disease and other atherosclerotic dise ase with antibodies against C. pneumoniae. 2. C. pneumoniae could be d etected with different techniques (PCR, immunhistology, electromicrosc opy, culture) in a high percentage in atheromas from different sites. 3. Three international studies with macrolides in coronary heart disea se were successful. 4. The target cells of atherosclerosis (endothelia ; macrophages, muscle cells) can be infected by C. pneumoniae in vitro . 5. Positive animal experiments. The Koch-Henle criteria for the proo f of the etiology are largely fulfilled - even if there are doubts abo ut the validity of these criteria in chronic local infections. A numbe r of unexplainable aspect of atherosclerosis can be seen in a new ligh t. The higher incidence of coronary heart disease in young males has a parallel in the remarkable androtropism of many bacterial diseases (p neumococcal pneumonia, tuberculosis). The reduction of incidence of at herosclerotic diseases since 1965 can be explained by the much higher intake of doxycyclin and macrolides. The low incidence of coronary hea rt disease in France - sometimes regarded as an effect of red wine - c an be explained as a result of a much higher use of antichlamydial ant ibiotics. The increase of inflammatory parameters (C-reactive protein, fibrinogen, leucocytes) before acute coronary infarction are not risk factors but signs of an active chronic infection. The interpretation i s possible. that atherogenic changes in lipids like increase of LDL an d decrease of HDL are not risk factors but consequence of chronic arte rial infection by chlamydia. The low incidence of atherosclerosis in t he tropics - despite high frequency of chlamydial infection-is difficu lt to explain Vascular infection can be related with the age of the pa tient at the primary infection. With low hygiene,intestinal primary in fections in early childhood can be possible. Arterial infection would be thus a result of a primary infection in adolescence (''yet another poliomyelitis story''). There are good arguments for the thesis that C . pneumoniae is the primary cause of atherosclerosis and not a seconda ry invader. The consequence, nevertheless, is similar: Antibiotics get a key role. The macrolides roxithromycin, azithromycin: clarithromyci n and the tetracyclin doxycyclin fulfill the criteria as potential ant ichlamydial agents. In general a longer treatment (6 to 8 to 12 weeks) seems advisable. It is neccessary to start international studies with antibiotics in coronary infarction and other clinical manifestations of atherosclerosis. The relevant antibiotics licensed for chlamydial i nfections are cheap and safe. Despite of the urgent need for controlle d studies, it seems already justified to treat high-risk patients with antibiotics. Meticulous protocols and long-term control of patients a re necessary to evaluate the therapeutic effects. Preventive studies i n patients without clinical manifestation of atherosclerosis are urgen tly needed. The risks of resistance or side effects are neglectable. b ut the organisation of such studies would be very difficult.