STD

I. INTRODUCTION

II. PELVIC INFLAMMATORY DISEASE

A. CHLAMYDIA

1. Symptoms

  • Painful or painless sores

  • Blood in urine

  • Burning sensation when urinating

  • Rashes

  • Itching

  • Bumps

  • Warts

  • Unusual discharge

2. Laboratory Tests

  • Tissue Culture

    • Gold standard for diagnosing Chlamydia trachomatis

    • Specificity approaching 100%; sensitivity 60% - 90%

  • Enzyme Immunoassay (EIA)

    • Non-amplified tests, e.g., Chlamydiazyme

    • Sensitivity: 85%, Specificity: 97%

    • Screening test—confirmatory tests required

  • Nucleic Acid Hybridization (NA Probe)

    • e.g., Gen-Probe Pace-2

    • Sensitivity 75% - 100%; specificity greater than 95%

  • DNA Amplification Assays

    • Polymerase Chain Reaction (PCR) and Ligase Chain Reaction (LCR)

    • Sensitivity: 95% for PCR, 85-98% for LCR

    • Specificity approaches 100%

B. NON-GONOCOCCAL URETHRITIS

C. GONORRHOEA

1. General Characteristics

  • Neisseria gonorrhoeae

    • Gram-negative diplococci

    • Fastidious and requires a moist atmosphere with CO₂ for growth

2. Important Human Pathogens

  • Neisseria species cause infections in humans, with pathogenic impact in urogenital, ocular, and systemic diseases.

3. Associated Disease

  • Gonorrheal infections lead to conditions such as urethritis, cervicitis, salpingitis, pelvic inflammatory disease (PID), and potentially disseminated disease.

4. Gonorrhea

  • To be explored further

D. NEISSERIA GONORRHOEAE

1. General Characteristics

  • Transmission modes include sexual intercourse and mother to child during birth.

2. Symptoms

  • Male Symptoms:

    • Discharge from the penis

    • Burning during urination

    • Testicular pain and swelling

    • Low-grade fever

  • Female Symptoms:

    • Vaginal discharge

    • Lower abdominal pain

    • Bleeding between menstrual periods

    • Low-grade fever

3. Clinical Manifestations

  • May include proctitis, arthritis, and conjunctivitis.

4. Epidemiology

  • 650,000 cases annually in the U.S., with high prevalence among sexually active individuals.

5. Pathogenesis

  • Characteristics include adherence to mucous membranes, internalization, and evasion of host immune responses.

6. Laboratory Characterization

  • Essential for diagnosing via gram-stains, cultures, and molecular assays.

7. Prevention and Treatment

  • Treatment involves antibiotics, with ceftriaxone being the first-line choice.

III. GENITAL ULCER DISEASE

A. SYPHILIS

1. SPIROCHETES

  • Caused by Treponema pallidum, which is a gram-negative spirochete.

2. Symptoms and Stages of Syphilis

  • Primary: Chancre formation, painless sore at entry site. Symptoms appear 10-90 days post-exposure.

  • Secondary: Systemic spread leading to rashes and systemic symptoms 2-8 weeks post-initial symptoms.

  • Latent: Symptoms may resolve, but internal damage occurs.

  • Tertiary: Long-term effects leading to severe health complications.

3. Diagnosis and Therapy

  • Diagnosis often utilizes serological tests and dark field microscopy; treatment typically with penicillin.

B. HERPES SIMPLEX VIRUS

1. Clinical Manifestations

  • Characterized by painful vesicular eruptions on the genitals and mouth. Symptoms may appear 2-20 days post exposure.

2. Diagnosis

  • PCR, serology, and culturing methods are used.

3. Epidemiology of Genital Herpes

  • Increased incidences reported, representing a significant public health concern.

4. Epidemiology of HSV Infections

  • Many carriers remain asymptomatic, leading to silent transmission.

5. Prevention and Treatment

  • Acyclovir is commonly used, but usage in pregnancy is often contraindicated.

C. HSV-CONGENITAL/PERIANAL

1. Clinical Manifestations

  • Specific signs and symptoms reflect severe potential neonatal complications.

2. Treatment

  • Acyclovir and careful monitoring during pregnancy are required.

3. Prevention

  • Proper screening and management during pregnancy to minimize transmission.

4. Diagnosis

  • Diagnosis techniques similar to genital herpes, including primary lesion sampling and serology.

5. Serology

  • Seroconversion tests to establish patterns of natural history.

6. When Do We Test for HSV-2

  • Testing recommended for symptomatic patients and high-risk populations.

D. HUMAN PAPILLOMAVIRUS

1. HISTORY

  • Identification links HPV to cervical cancer; HPV is the most prevalent STI.

2. MORPHOLOGY AND TRANSMISSION

  • Spread sexually, with vertical transmission possible.

3. MECHANISM OF ACTION

  • Induces host cell proliferation which may potentially lead to malignancies.

4. SIGNS AND SYMPTOMS

  • Warts and dysplasia as key clinical presentations.

5. PREVENTION & CURE

  • Vaccines available, though treatment does not eradicate the virus.

6. TREATMENT

  • Varied treatments based on wart presentations and symptomatology.

7. GENITAL WARTS, HPV, AND CERVICAL CANCER

  • Links between HPV types, warts, and oncogenesis.

8. TYPES OF HPV

  • High-risk types (e.g., HPV 16, 18) associated with increased cancer risk.

E. TRICHOMONIASIS

1. CHARACTERISTICS AND MORPHOLOGY

  • Pear-shaped flagellated parasite.

2. SPECIES OF TRICHOMONAS IN MAN

  • Trichomonas vaginalis is the only pathogenic species in humans.

3. TRICHOMONIASIS

  • Condition results in inflammation and discharge.

4. MODE OF TRANSMISSION

  • Primarily through sexual contact, also via contaminated objects.

5. SIGNS AND SYMPTOMS

  • Characterized by a foul-smelling, greenish discharge.

6. DIAGNOSIS

  • Diagnosis involves microscopy and culture of the discharge.

7. TREATMENT

  • Metronidazole is the primary treatment, with variations based on gender and susceptibility.

IV. CANDIDIASIS

A. VULVOVAGINAL CANDIDIASIS

  • Symptoms: itching, soreness, and discharge often misdiagnosed.

B. CANDIDA INFECTIONS OF THE VAGINAL MUCOSA

1. CLINICAL FEATURES

  • Identify characteristics as not definitive.

2. DIFFERENTIAL DIAGNOSIS

  • Distinguishing from BV, trichomoniasis, and other causes.

3. CULTURE DIFFERENTIATION

  • Importance to confirm diagnosis with laboratory tests.

4. TREATMENT

  • Antifungal medications; specifics vary depending on infection type.

5. TREATMENT AND PREGNANCY

  • Safety of treatment options to ensure maternal and fetal health considerations.

V. References

  • Powerpoint presentation of Dr. Lorna Amoranto

  • Jawetz, Melnick & Adelberg’s Medical Microbiology

VI. PRACTICE QUESTIONS

Questions

  1. Which of the following is the gold standard laboratory test for diagnosing Chlamydia trachomatis?

  • C. Tissue Culture

  1. A patient presents with a firm, round, painless genital ulcer. Which organism is most likely responsible?

  • B. Treponema pallidum

  1. Which of the following is a major reservoir for Neisseria gonorrhoeae transmission?

  • B. Asymptomatic females

  1. What is the most common sexually transmitted infection worldwide?

  • B. Human Papillomavirus (HPV)

  1. Which diagnostic finding is characteristic of Trichomonas vaginalis infection?

  • C. Pear-shaped flagellated trophozoites

  1. Which HPV types are considered “high risk” for cervical cancer?

  • B. HPV 16 and 18

  1. In which stage of syphilis do symptoms such as rash, mucous patches, and condylomata lata appear?

  • B. Secondary

  1. Which antiviral drug is commonly used to treat HSV infections but is relatively contraindicated in pregnancy?

  • A. Acyclovir

  1. What is the first-line treatment for uncomplicated gonococcal infections?

  • B. Ceftriaxone

  1. Which of the following is NOT a typical symptom of vulvovaginal candidiasis?

  • B. Greenish foul-smelling discharge