Aetiological diagnosis of STI is problematic in many settings. It places constraints on time, resources, costs and access to treatment. In addition, the sensitivity and specificity of available tests can vary significantly, thus, affecting negatively, the reliability of laboratory testing for STI diagnosis. In settings where laboratory facilities are available there must be suitably qualified personnel with adequate training to perform technically demanding procedures, and the establishment of external quality control is mandatory.

Few developing country health facilities have the laboratory equipment or skills required for aetiological diagnosis of STI. To overcome this, a syndrome-based approach to the management of STI patients was developed and promoted in a large number of countries in the developing world. Syndromic management is based on the identification of consistent groups of symptoms and easily recognized signs (syndromes), and the provision of treatment that will deal with the majority or most serious organisms responsible for producing a syndrome. WHO developed a simplified tool (a flowchart or algorithm) to guide health workers in the implementation of syndromic management.

Syndromic management for urethral discharge in men and genital ulcers in men and women has proved to be both valid and feasible. It has resulted in adequate treatment of large numbers of infected people, and is inexpensive, simple and very cost-effective.

WHO also developed syndromic case management algorithms for women with symptoms of vaginal discharge and/or lower abdominal pain. However, it is important to recognize the limitations of the vaginal discharge algorithms, particularly in the management of cervical (gonococcal and chlamydial) infections. In general, but especially in low prevalence settings and in adolescent females, endogenous vaginitis rather than STI is the main cause of vaginal discharge. While attempts have been made to increase the sensitivity and specificity of the vaginal discharge algorithm for the diagnosis of cervical infection, through the introduction of an appropriate, situation-specific risk assessment, both remain low. Moreover, some of the risk assessment questions based on demographics, such as age and marital status, tend to incorrectly classify too many adolescents as at risk of cervical infection. Therefore, there is a need to identify the main STI risk factors for adolescents in the local population and tailor the risk assessment accordingly. For adolescents in particular it may be preferable to base the risk factors on sexual behaviour patterns.

Recommendations for treatment using a syndrome-based approach are given in section 2.