Vol.53 No.10 October 2005
Respiratory Infections a chronological view
Kyorin University, School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo, Japan
Abstract
The classical term "pneumonia" was first noted by Hippocrates in the 4th century BC, as a serious illness in the thorax. In 1819, Laennec recorded the physical findings of chest abnormalities obtained by percussion and auscultation with the stethoscope he invented, and compared them with the post mortem findings. Then, the pneumonia and pneumonic consolidation, were differentiated from pleural effusion, and the criteria for pneumonia were classified anatomically into lobar and lobular pneumonia.
The causative bacteria of infectious diseases, including pneumonia, were discovered in late the 19th century. This fact induced at least three important things, (1) evidence that pneumonia is clearly caused by invasion of microorganisms into lung through airway or blood stream. (2) analysis of serotyping of bacterial capsules of pneumococci led to development of type specific serotherapy and (3) synthesis of chemotherapeutic agents based on the idea that dyestuffs enter bacterial bodies.
In the 1920s∼1930s, along with increasing popularity of type specific serotherapy, an accurate determination of the causative organisms was attached importance to diagnosis of pneumonia, because the Type specific serotherapy was only the way to get a favorable prognosis of the patients with pneumococcal pneumonia. At the same time, bacteriology-based diagnosis, such as "pneumococcal pneumonia", became more popular than anatomy-based diagnosis. Such an active observation toward the bacteriologic examination, on the other hand, led to postulation of the existence of a different type of pneumonia, "atypical pneumonia", whose causative organisms were speculated to be viruses or transfilterable agents. Mycoplasma pneumoniae (1962), Legionella pneumophila (1976), Chlamydia pneumoniae (1980s) and SARS-Co-V (2002) were later discovered.
In the late 20th century, the incidence of opportunistic pneumonia increased in association with the aging of society and the increased longevity of immunodeficient patients. Also, the incidence of Pneumocystis carinii pneumonia re-emerged, parallel with the spread of HIV infection, and pneumonia caused by antibacterial agent resistant strains, for instance MRSA or PRSP emerged. In this situation, a new concept of the community acquired pneumonia (CAP) and the hospital acquired pneumonia (HAP) was populariged (1980s). Since the point of this criteria was well reflected the correlation between preference for the causative organisms and the patients background, this classification was convenient for the choice of antimicrobial agent based on empirical evidence. Recently, however, the close relationship between pathogens and patient background has sometimes became unclear, because patients with immunodeficiency diseases, patients with chronic intractable diseases and elderly patients are increasingly living in community. It indicates that the terminology of CAP or HAP has to reconsider to go back the starting point.
Although the purulent exacerbation of chronic bronchitis was postulated by the infection with numerous microorganisms, the bacterial analysis of chronic bronchitis remained incomplete until 1940s. In the 1950s, a significant role of Haemophilus influenzae was prevailed. A resurgence of interest in chronic bronchitis was stimulated by the increasing incidence of the disease in association with widespread air pollution, particularly in industrial areas and in big cities. In addition, infected cystic fibrosis and infected diffuse panbronchiolitis were recognized as intractable airway infections with persistant colonization of bacterial biofilms. A therapeutic effect of long term use of 14 or 15 membered macrolides for diffuse panbronchiolitis was indicated. Multifaceted basic studies on approach to possible mechanisms of the macrolide effect was performed. Interestingly, an autoimmune factor, BPI-ANCA, was detected in the patients with chronic infection of cystic fibrosis and diffuse panbronchiolitis, and stimulated an interesting assignment on the thinking of correlation between autoimmune factors and chronic infection. Moreover, biofilm research developed the quorum sensing system in bacterial communication. The inhibition of this system is thought a key-role in suppression of biofilm formation, which often causes a persistent infection of the airway. Furanone compounds and 14 or 15 membered macrolides are investigating as the role of quorum sensing inhibitors.
Along the chronological advancement concerning with microorganisms, clinical features and therapeutic methods, the respiratory infections were reviewed. There were numerous contributions in the history of respiratory infections. What I want to emphasize is that everyone worked in each generation possessed his own knowledge, his own insight, and his own enthusiam.
Key word
respiratory infections, history, bacteriology, clinical feature, therapeutic methods
Received
September 13, 2005
Accepted
September 27, 2005
Jpn. J. Chemother. 53 (10): 603-618, 2005
