Immunopathogenesis of Chlamydial Pelvic Inflammatory Disease: The Role of Heat-Shock Proteins

Editorial Pelvic inflammatory disease (PID) is the most important complication of sexually transmitted chlamydial infections, causing major medical, social, and economic problems. PID is an ascending infection, with well over half of the cases caused by Chlamydia trachomatis (CT), Neisseria gonorrhoeae (GC), or both. However, other microorganisms representing abnormal vaginal flora, such as those present in bacterial vaginosis, are also commonly involved. ,2 GC rates have rapidly decreased in most developed countries, while CT rates have remained high. Thus, the relative role of CT in the etiology of PID has increased. In the 1980s, it also became obvious that the clinical spectrum of PID manifestations was changing. An increasing proportion of cases were atypical or silent, and the typical "textbook" PID was becoming a rare disease. Subsequently, there has been a dramatic drop in the incidence of inpatient PID. Clearly, this change reflects a change in the etiologic pattern of PID. A large number of seroepidemiologic studies support the concept of silent PID by demonstrating a strong link between serum antibodies to CT and tubal factor infertility or ectopic pregnancy in patients with or without histories of PID. Concern about the problem of unrecognized PID has also led to a fundamental change in the recommendations for PID diagnosis. The following set of simple, easily ascertained minimum clinical criteria should trigger antibiotic treatment for probable PID: lower abdominal tenderness; bilateral adnexal tenderness; cervical motion tenderness; no evidence of a competing diagnosis, e.g., positive pregnancy test, acute appendicitis. 4 This important change in direction, from a laboratory-and laparoscopy-based diagnosis toward a syndromic diagnosis, should increase sensitivity by decreasing the false-negative rate. Although the more sensitive approach will result in some unnecessary antibiotic treatment, it will also lead to the provision of proper therapy earlier in the course of PID. Delay of care, as well as unrecognized PID, is an important cause of impaired fertility, particularly in chlamydial PID. s Worldwide, the magnitude of PID-related morbidity is still enormous. The proportion of tubal factor infertility of all infertility ranges from 37 % in developed countries to 85% in developing countries. 6 Our understanding of the pathogenesis of PID and PID-related sequelae has increased along with a better understanding of the immunopathogenesis of CT infection. Early studies had already suggested that a single acute infection per se could not account for all the pathology associated with chlamydial disease. 7 The persistence of chronic inflammation …