2025 – PAGE 94 – OB/GYN AND SOME STDs

DIZYGOTIC TWINS

Dizygotic twins occur when two separate eggs are fertilized, so these are NOT identical. Instead they are called “fraternal twins,” and they are dichorionic. For the test, these twins always have their own amniotic sacs and their own placenta (Di/Di).

• PEARL: Confused? Break down the words and you’ll be fine (Zygotic, Amniotic, Chorionic).

GYNECOLOGY & SOME STDs

PARENTAL CONSENT

Parental consent is NOT needed to treat a child/adolescent for STDs or for substance abuse.

(DOUBLE TAKE) CHLAMYDIA TRACHOMATIS

Chlamydia trachomatis can cause urethritis, conjunctivitis and pelvic inflammatory disease (PID). In neonates, it can cause pneumonia associated with a staccato cough. PID can lead to ectopic pregnancies and infertility. Eye infections can lead to blindness. Conjunctivitis in a neonate (less than a month old) should raise concern for this as the etiology (vertical transmission). It’s an obligate intracellular anaerobe. Getting cultures is difficult, so order PCR of CELLS, secretions, or urine. Chlamydia can also cause lymphogranuloma venereum (LGV), which is an STD that initially starts with small, nontender papules or shallow ulcers that resolve. Then a TENDER UNILATERAL INGUINAL lymph node appears that can rupture, relieve the pain, and then possibly drain for months.

• ­SEXUALLY TRANSMITTED DISEASE (STD): Treat with DOXYCYCLINE for 7 days. If the patient is given doxycycline and there is treatment failure, a recurrence, a concern for noncompliance, or a doxycycline allergy, then treat with a single dose of AZITHROMYCIN or treat with LEVOFLOXACIN for 7 days. Test for other STDs including gonorrhea, syphilis, and HIV and treat if positive.
• ­CONJUNCTIVITIS: Treat with oral erythromycin to eradicate nasopharyngeal colonization, which can lead to pneumonia.
• ­(DOUBLE TAKE) LYMPHOGRANULOMA VENEREUM SEROVAR is an STD caused by Chlamydia trachomatis. It is rare in the U.S. but more common in tropical areas. It starts as small nontender papules or shallow ulcers that resolve. Eventually, a TENDER UNILATERAL INGUINAL lymph node appears. Pain is relieved when it ruptures. The node can continue to drain for months. Treat with DOXYCYCLINE or erythromycin.
• ­PEARL: In general, when you think the diagnosis is due to a Chlamydia species, choose doxycycline or a macrolide (usually erythromycin). Also, this is an intracellular organism. Look for the phrase “intracytoplasmic inclusions.”
• PEARL: While chlamydia is often said to be the most common STD, that’s not the case. It’s the most common BACTERIAL STD, and it’s the most commonly REPORTED STD. HPV is the most common STD.