20.2 Reproductive Tract Infections & STIs: Syphilis, Genital & Neonatal Herpes, HPV, Molluscum, CMV, Trichomoniasis & Vaginitis, Cervicitis, Prostatitis and Orchitis

Why this area matters

The TOS reproductive tract area lists:

• genital herpes and neonatal herpes;
• syphilis;
• papillomavirus and molluscum contagiosum;
• cytomegalovirus;
• HIV/AIDS;
• cervicitis, prostatitis and orchitis.

The Philippines has a rapidly rising HIV epidemic, and STIs often travel together. The DOH pursues the elimination of mother-to-child transmission of HIV, syphilis and hepatitis B, so pregnant women are screened for all three. Board questions test syphilis serology and staging, the right penicillin preparation, congenital infections, oncogenic HPV types and the vaginal discharge triad.

Syphilis

Treponema pallidum & Syphilis

Treponema pallidum subspecies pallidum is a thin, tightly coiled spirochete that cannot be cultured on artificial media. It is visualized by darkfield microscopy from chancre exudates or diagnosed through serologic testing:

• Non-Treponemal Tests (VDRL, RPR): Detect anticardiolipin antibodies. Sensitive for screening and monitoring treatment response (titers fall after therapy); false positives occur in SLE, pregnancy, malaria, and antiphospholipid syndrome.
• Treponemal Tests (FTA-ABS, TP-PA): Detect specific treponemal antibodies; remain positive for life regardless of treatment; used for diagnostic confirmation.
• Clinical Stages: Primary syphilis presents with a solitary, painless hard chancre with clean borders and indurated base. Secondary syphilis manifests with a generalized maculopapular rash involving the palms and soles, condylomata lata (broad, flat, painless genital warts), and generalized lymphadenopathy. Tertiary syphilis develops years later with gummas (chronic granulomatous lesions in bone/skin), aortitis (vasa vasorum destruction causing thoracic aortic aneurysm), and neurosyphilis (tabes dorsalis, Argyll Robertson pupils that accommodate to near vision but do not react to light). Treatment of choice is Benzathine Penicillin G.

Additional syphilis essentials:

• Latent syphilis has positive serology without signs. It is early latent if infection was within 1 year and late latent after that.
• Treatment:
  • Primary, secondary and early latent syphilis: benzathine penicillin G 2.4 million units IM once.
  • Late latent syphilis: benzathine penicillin G once weekly for 3 weeks.
  • Neurosyphilis, including ocular syphilis: aqueous crystalline penicillin G IV for 10 to 14 days.
• The Jarisch-Herxheimer reaction (fever, headache and myalgia within 24 hours of treatment) is caused by released treponemal antigens. It is not a penicillin allergy.
• Pregnancy: penicillin is the only drug proven to treat the fetus, so women allergic to penicillin are desensitized.
• Congenital syphilis:
  • Early: rhinitis ("snuffles"), rash with peeling of the palms and soles, hepatosplenomegaly and periostitis.
  • Late: Hutchinson teeth, mulberry molars, saddle nose, saber shins, interstitial keratitis and eighth nerve deafness.
• Follow-up: a fourfold fall in RPR titer shows response to treatment.

Genital herpes and neonatal herpes

• Genital herpes:
  • Usually caused by HSV-2, but increasingly by HSV-1.
  • A primary episode brings painful grouped vesicles on a red base that become shallow ulcers, with fever, tender inguinal nodes and dysuria.
  • The virus becomes latent in the sacral ganglia and reactivates in milder recurrences.
  • Asymptomatic shedding transmits most infections.
  • Treatment is acyclovir, valacyclovir or famciclovir. Suppressive therapy reduces recurrences and transmission.
• Neonatal herpes:
  • Most infections are acquired during delivery. The risk is highest when the mother has a primary infection near term, because she has not yet made protective antibodies.
  • It appears in three forms:
    • skin, eye and mouth disease;
    • CNS disease (encephalitis at 2 to 3 weeks);
    • disseminated disease, with hepatitis, pneumonitis and DIC.
  • It is treated with IV acyclovir.
  • Cesarean delivery is recommended for women with active genital lesions or prodromal symptoms at labor.

Human papillomavirus (HPV)

• HPV is a non-enveloped double-stranded DNA virus that infects basal squamous cells through microabrasions.
• Low-risk types 6 and 11 cause anogenital warts (condylomata acuminata) and juvenile recurrent respiratory papillomatosis, acquired at birth.
• High-risk types 16 and 18 cause about 70% of cervical cancers and many anal, penile, vulvar and oropharyngeal cancers.
• Oncogenesis: the viral oncoproteins E6 degrades p53 and E7 inactivates Rb. Infected cells show koilocytes, squamous cells with a wrinkled nucleus and a perinuclear halo.
• Treatment of warts: cryotherapy, trichloroacetic acid, podophyllotoxin or imiquimod. Podophyllin and imiquimod are avoided in pregnancy.
• Prevention: HPV vaccine is most effective before sexual debut. The DOH gives it to young adolescent girls through school-based immunization. Cervical screening is discussed in Gynecology.

Molluscum contagiosum and cytomegalovirus

• Molluscum contagiosum:
  • Caused by a poxvirus (a large DNA virus).
  • Lesions are pearly, dome-shaped, umbilicated papules. In children they appear anywhere on the body. In adults they appear on the genitals and are sexually transmitted.
  • Lesions are extensive or giant in advanced HIV.
  • Histology shows large eosinophilic intracytoplasmic molluscum bodies.
  • Lesions resolve on their own over months, or are treated by curettage or cryotherapy.
• Cytomegalovirus (CMV):
  • Spreads through saliva, sexual contact, the placenta, breast milk, transfusion and transplanted organs.
  • In healthy adults it causes a mononucleosis-like illness that is heterophile negative.
  • Congenital CMV is the most common congenital infection. It causes:
    • microcephaly and periventricular calcifications;
    • chorioretinitis;
    • petechiae ("blueberry muffin" rash);
    • sensorineural hearing loss, which may appear later.
  • In AIDS and transplant patients it causes retinitis, colitis and esophagitis, with "owl's eye" inclusions. It is treated with ganciclovir or valganciclovir.

Urogenital Protozoan Infections: Trichomonas vaginalis

Trichomonas vaginalis is an anaerobic, flagellated protozoan that colonizes the squamous epithelium of the lower human genital tract. It is the etiologic agent of trichomoniasis, one of the most prevalent non-viral sexually transmitted infections worldwide.

Morphological Hallmark: Absence of Cyst Stage

An essential parasitological principle is that Trichomonas vaginalis exists exclusively as a motile trophozoite—there is NO cyst stage in its life cycle! Because it lacks a protective cyst, the trophozoite cannot survive long outside the human body and is transmitted almost exclusively via direct sexual intercourse.

Under microscopy, the trophozoite is oval or pear-shaped (10 to 20 um), possessing four anterior flagella, a fifth recurrent flagellum that forms an undulating membrane extending half the length of the cell, and a rigid, sharply pointed longitudinal axostyle. On fresh saline wet mount preparations of vaginal or urethral discharge, it exhibits characteristic rapid, jerky, twitching motility.

Clinical Manifestations

In women, infection manifests as acute or subacute vaginitis characterized by a profuse, thin, foamy or frothy, greenish-yellow, foul-smelling vaginal discharge, accompanied by severe vulvovaginal pruritus, dysuria, and dyspareunia. On speculum examination, the vaginal walls are intensely erythematous, and the ectocervix demonstrates punctate petechial hemorrhages, producing the pathognomonic "strawberry cervix" (colpitis macularis). The vaginal pH is elevated, characteristically measuring > 4.5 (distinguishing it from Candida vulvovaginitis, which presents with normal pH < 4.5).

In men, Trichomonas resides in the urethra and prostate gland, remaining predominantly asymptomatic or causing mild, self-limited non-gonococcal urethritis or epididymitis.

Management & The Partner Treatment Mandate

First-line therapy consists of oral Metronidazole (500 mg orally twice daily for 7 days) or oral Tinidazole (2 g orally as a single dose). Topical intravaginal metronidazole gel is ineffective because it achieves inadequate therapeutic drug levels in the urethra and periurethral glands.

The Simultaneous Partner Treatment Rule: Because high rates of asymptomatic carriage exist in male partners and unprotected intercourse results in rapid reinfection, all sexual partners of the index patient must be treated simultaneously, regardless of symptoms. Patients must abstain from sexual intercourse until both partners complete therapy, and are traditionally counselled to avoid alcohol during nitroimidazole therapy because of a possible disulfiram-like reaction.

The vaginitis triad

Bacterial vaginosis is not a sexually transmitted infection that requires partner treatment, but in pregnancy it is linked to preterm birth.

Cervicitis, prostatitis and orchitis

• Cervicitis:
  • mucopurulent endocervical discharge and a friable cervix that bleeds on contact;
  • usually caused by C. trachomatis or N. gonorrhoeae, and also HSV, Trichomonas and M. genitalium;
  • untreated, it ascends to cause PID.
• Acute bacterial prostatitis:
  • fever, perineal pain, dysuria and a tender, boggy prostate;
  • usually caused by E. coli and other Enterobacterales;
  • avoid vigorous prostatic massage, which can cause bacteremia;
  • give a fluoroquinolone or TMP-SMX for several weeks.
  • Chronic bacterial prostatitis causes recurrent UTIs with the same organism.
• Epididymo-orchitis:
  • In sexually active men under 35, it is usually caused by C. trachomatis or N. gonorrhoeae: give ceftriaxone plus doxycycline.
  • In older men, or men who practice insertive anal sex, enteric organisms are the cause: give levofloxacin.
  • Lifting the scrotum relieves the pain (Prehn sign). Testicular torsion must be excluded with Doppler ultrasound.
• Mumps orchitis:
  • occurs in about a third of men who get mumps after puberty, about a week after parotitis;
  • usually unilateral;
  • may cause testicular atrophy and subfertility, but rarely sterility;
  • prevented by MMR vaccine.