Genital Herpes

Etiopathogenesis - Viral Villains

• Causative Agents: Herpes Simplex Virus (HSV) - DNA virus (Herpesviridae).
  • HSV-1: Traditionally orofacial; increasing anogenital cases.
  • HSV-2: Predominant anogenital cause; more recurrences.
• Key Features:
  • Lifelong latency in sacral sensory ganglia.
  • Reactivation triggers: Stress, menses, illness, immunosuppression.
• Transmission:
  • Direct contact with lesions or infected secretions.
  • Sexual: Vaginal, anal, oral.
  • Asymptomatic viral shedding is common.
  • Vertical: Intrapartum (mother-to-child).

⭐ HSV-2 is the primary cause of genital herpes & has more frequent recurrences than genital HSV-1.

Clinical Features - Spotting Sores

• Primary Infection (First Episode):

  • Incubation: 3-7 days (range 2-14).
  • Prodrome: Fever, malaise, myalgia, local pain/paresthesia.
  • Lesions: Multiple, bilateral, grouped vesicles → painful ulcers → crusting. Heal in 2-4 weeks.
    • Locations: Penis, vulva, perineum, cervix, anus.
  • Systemic symptoms common; tender inguinal lymphadenopathy.
  • Complications: Aseptic meningitis, urinary retention (Elsberg syndrome).

• Recurrent Infection:

  • Prodrome: Localized tingling, burning, or pain (milder, shorter).
  • Lesions: Fewer, unilateral, smaller, less painful. Heal in 7-10 days.
  • Systemic symptoms rare.
  • Triggers: Stress, illness, menses, local trauma.

• Asymptomatic Viral Shedding: Common between outbreaks; source of transmission.

⭐ Most primary genital herpes infections are subclinical or unrecognized; many individuals with HSV-2 are unaware of their infection.

Diagnosis - Nailing It

• Clinical: History of recurrent, painful genital vesicles or ulcers.
• Lab Tests (from active lesions):
  • PCR (NAAT): Gold Standard. Highest sensitivity & specificity.

    ⭐ PCR is the investigation of choice (IOC) for active lesions & HSV meningitis/encephalitis.

  • Viral Culture: Specific, but sensitivity ↓ with lesion healing.
  • Tzanck Smear: Shows multinucleated giant cells (📌 Tzanck for this quick clue!). Low sensitivity, not type-specific.
• Serology (Type-specific IgG): Detects past infection; useful for asymptomatic/atypical cases or partner evaluation. Not for acute diagnosis.

Management - Antiviral Arsenal

• Drugs: Acyclovir (ACV), Valacyclovir (VCV), Famciclovir (FCV).
• Primary Episode (7-10 days):
  • ACV: 400 mg TID.
  • VCV: 1 g BID.
  • FCV: 250 mg TID.
• Episodic (Recurrent): Initiate at prodrome/first sign.
  • ACV: 800 mg TID (2d) OR 400 mg TID (5d).
  • VCV: 500 mg BID (3d) OR 1 g OD (5d).
  • FCV: 1 g BID (1d) OR 125 mg BID (5d).
• Suppressive (≥6 recurrences/yr):
  • ACV: 400 mg BID.
  • VCV: 500 mg - 1 g OD.
  • FCV: 250 mg BID.
• Pregnancy:
  • ACV preferred. Suppressive therapy from 36 weeks gestation (e.g., ACV 400 mg TID or VCV 500 mg BID) to ↓ risk of outbreak at delivery & ↓ Cesarean section rates.

⭐ For Acyclovir-resistant HSV, particularly in immunocompromised individuals, Foscarnet or IV Cidofovir are alternative treatments.

Complications & Prevention - Risks & Reassurance

• Complications:
  • Neonatal herpes (↑risk if primary infection in 3rd trimester)
  • Aseptic meningitis
  • Urinary retention (Elsberg syndrome)
  • Erythema multiforme
  • Proctitis (MSM)
• Prevention:
  • Consistent condom use (↓risk, not eliminative)
  • Antiviral suppressive therapy (↓transmission)
  • Avoid sexual contact during outbreaks
• Reassurance:
  • Not life-threatening in immunocompetent
  • Effective treatments manage symptoms & ↓recurrences

⭐ Neonatal herpes: ~50% risk if mother acquires primary genital herpes near delivery; <1% if recurrent herpes or seropositive before pregnancy. Cesarean delivery indicated for active lesions at term in primary infection to prevent transmission.

High‑Yield Points - ⚡ Biggest Takeaways

• Caused mainly by HSV-2; HSV-1 less common for genital lesions.
• Presents with painful, grouped vesicles or ulcers on an erythematous base.
• Tzanck smear (multinucleated giant cells); PCR is diagnostic gold standard.
• Acyclovir (IV for severe/disseminated), Valacyclovir, Famciclovir are first-line.
• Recurrences are common; suppressive therapy for ≥6 episodes/year.
• Complications: aseptic meningitis, neonatal herpes, Erythema Multiforme.
• No cure; virus establishes latency in sacral sensory ganglia.