Gulshan Sethi The vulva can be the primary site of infection in a number of sexually transmitted infections (STIs), as seen in previous chapters. There are some less common STIs, including the ectoparasite infections, which can also involve the vulva and are covered in this chapter. M. genitalium is the smallest known self‐replicating bacterium [1] and is predominantly found in the genitourinary tract of both males and females. The absence of a cell wall means it cannot be detected on gram staining of a specimen. By establishing intracellular infection and antigenic and phase variation of its surface‐expressed proteins, it is able to evade the adaptive immune system [1,2]. M genitalium infection may persist for months or years in asymptomatic individuals. It is found in genital specimens of 10‐13% of women with pelvic inflammatory disease (PID) [3,4]. Although the pathological features of M. genitalium infection are thought to be due mainly to the host response, the organism has been shown to directly cause cilial damage in human fallopian cell culture. In women, several studies support the association of M. genitalium infection with cervicitis (particularly in the context of postcoital bleeding) and PID [5–7]. Most M. genitalium infection is asymptomatic and non‐pathogenic, and treating large numbers of individuals may potentially cause harm at a population level by driving further antimicrobial resistance. The ease with which M. genitalium is able to develop resistance is of concern and presents challenges in treatment, and hence testing recommendations are restricted to those with specific indicator symptoms, including women with PID and/or current sexual partners of a person with confirmed M. genitalium infection. Current guidelines recommend detection of M. genitalium through nucleic acid amplification tests (NAATs) followed by testing for mutations associated with macrolide resistance in order to guide antibiotic treatment [8]. Treatment is dependent on resistance testing [8]. If there is no known macrolide resistance, first‐line therapy is doxycycline 100 mg twice daily for 7 days followed by azithromycin 1 g immediately followed by 500 mg daily for 2 days. Second‐line treatment is moxifloxacin 400 mg daily for 10 days. In cases with known macrolide resistance, moxifloxacin 400 mg daily for 10 days is recommended. In complicated disease such as PID, an extended course of moxifloxacin 400 mg daily for 14 days is the treatment of choice. Patient information https://www.bashhguidelines.org/media/1226/mgen_pil_digital_p2_2019.pdf Last accessed September 2021. Chancroid is caused by the fastidious, gram‐negative coccobacillus Haemophilus ducreyi. The incubation period for chancroid is 3–7 days. Painful genital ulceration is the most common presentation, often associated with fluctuant lymphadenitis. The initial lesions are tender erythematous papules, most often on the vulva, cervix, and perianal area in women [9]. These rapidly progress to pustules, which rupture after a few days and develop into superficial ulcers with ragged and undermined edges. The bases of the ulcers are granulomatous with purulent exudate. The ulcers are soft and painful and may persist for months if left untreated. NAATs are the gold standard testing technique. DNA amplification tests have demonstrated that the sensitivity of H. ducreyi culture is 75% at best. Culture is particularly important in cases of suspected treatment failure to further characterise the bacterium for antimicrobial susceptibility [10–12]. Several antibiotic regimens have been recommended for confirmed cases of chancroid. Ceftriaxone as a single intramuscular injection of 250 mg or azithromycin, as a single 1 g oral dose, is used first line. The response is generally good, although failures, especially in HIV‐positive individuals, have been reported. Second‐line regimens include ciprofloxacin 500 mg orally twice a day for three days, or erythromycin orally 500 mg four times a day for seven days [13]. Patient information https://www.bashhguidelines.org/media/1029/chancroid‐pil‐screen‐edit.pdf Last accessed September 2021. Donovanosis (granuloma inguinale) is an increasingly rare infection which appears to be virtually eliminated and is seen mainly in sporadic cases in Papua New Guinea, southern Africa, and in parts of India and Brazil. A successful eradication programme was started in Australia in the 1990s [14]. It is an ulcerative condition caused by Klebsiella granulomatis (formerly Calymmatobacterium granulomatis). The risk of associated HIV infection is increased, and HIV testing is recommended for all cases [15]. The initial lesion is a firm papule or subcutaneous nodule that subsequently ulcerates. In women, this is usually on the labia or at the fourchette. The cervix may be involved, resulting in lesions that mimic a carcinoma, and extragenital lesions may occur in the mouth, larynx, nose, and on the chest. Four types of donovanosis are described [16]:
17
Other Sexually Transmitted Infections
Mycoplasma genitalium
Pathophysiology
Diagnosis
Treatment
Resources
Chancroid
Clinical features
Diagnosis
Treatment
Resources
Donovanosis
Clinical features
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
