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He who immerses himself in sexual intercourse will be assailed by premature ageing, his strength will wane, his eyes will weaken, and a bad odour will emit from his mouth and his armpits, his teeth will fall out and many other maladies will afflict him.

Moses ben Maimon (1135–1204), Mishneh Torah

Sexually transmitted infections (STIs) are a group of communicable infections, usually transmitted by sexual contact. Their incidence has been of widespread significance during the past 30 years and they are a major public health problem in all countries.

The STIs have developed a high profile in modern society with the advent of HIV infection, hepatitis B, Chlamydia trachomatis as a major cause of PID, the emergence of penicillin-resistant gonorrhoea and the increasing frequency of the human papilloma (wart) virus infection with its association with cervical cancer. STIs are summarised in Table 119.1.

Table 119.1

Sexually transmitted or acquired infections: causative organisms and treatment2,4

Key facts and guidelines

  • In Western society most patients with STIs are in the 15–30 years age group.

  • Gonorrhoea and syphilis are no longer the commonest STIs.

  • Chlamydial infection, hepatitis B, human papillomavirus and genital herpes are now common infections.

  • Not all STIs are manifest on the genitals.

  • Not all genital lesions are STIs.

  • The 5% rule:1

    • 5% of urethritis (STI) in males is lower UTI

    • 5% of lower UTI in females is urethritis (STI)

  • Chlamydia trachomatis is now the commonest cause of urethritis.

  • Chlamydia typically causes dysuria in men but may be asymptomatic. It usually causes no symptoms in women.

  • Gonorrhoea may cause no symptoms, especially in ...

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