Infectious Disease · Sexually Transmitted Infections
The facts most likely to be tested
Neisseria gonorrhoeae is a Gram-negative diplococcus that is oxidase-positive and requires Thayer-Martin agar for culture.
The first-line treatment for uncomplicated urogenital, rectal, or pharyngeal gonorrhea is a single dose of 500 mg intramuscular ceftriaxone.
Empiric treatment for Chlamydia trachomatis with doxycycline (100 mg BID for 7 days) is required if chlamydial infection has not been excluded.
Disseminated gonococcal infection typically presents as a triad of tenosynovitis, dermatitis (pustular or petechial lesions), and polyarthralgia.
Gonococcal purulent conjunctivitis in newborns is prevented by the routine administration of erythromycin ophthalmic ointment at birth.
Pelvic inflammatory disease (PID) caused by gonorrhea often presents with cervical motion tenderness, adnexal tenderness, and uterine tenderness.
Nucleic acid amplification testing (NAAT) is the gold standard diagnostic test for gonorrhea due to its high sensitivity and specificity.
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A 24-year-old female presents to the urgent care clinic complaining of lower abdominal pain and vaginal discharge for 3 days. She reports recent unprotected sexual intercourse with a new partner. On physical examination, she has cervical motion tenderness and mucopurulent cervical discharge. Her temperature is 100.4°F (38°C). A pelvic exam reveals adnexal tenderness on the right side.
What is the most appropriate empiric antibiotic regimen for this patient?
Intramuscular ceftriaxone plus oral doxycycline
The patient presents with clinical signs of PID; the standard treatment requires coverage for N. gonorrhoeae (ceftriaxone) and C. trachomatis (doxycycline) as per current CDC guidelines.
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Etiology / Epidemiology
Caused by Neisseria gonorrhoeae, a gram-negative diplococcus. High risk in sexually active young adults with multiple partners.
Clinical Manifestations
Presents with purulent urethral discharge and dysuria. Women are often asymptomatic carriers.
Diagnosis
Nucleic acid amplification test (NAAT) is the gold standard. Obtain samples from first-void urine or swabs.
Treatment
Ceftriaxone 500 mg IM is the first-line treatment. Do not use monotherapy if chlamydia is not ruled out.
Prognosis
Untreated leads to Pelvic Inflammatory Disease (PID) and infertility. High risk of disseminated gonococcal infection.
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Epidemiology & Etiology
Caused by the fastidious Neisseria gonorrhoeae, a gram-negative diplococcus. It is the second most common reportable STI in the US. Young age and unprotected sexual contact are the primary risk factors.
Pertinent Anatomy
Infection targets columnar epithelium of the endocervix, urethra, and rectum. The Skene's and Bartholin's glands serve as reservoirs for persistent infection.
Pathophysiology
The bacteria utilize pili for attachment to mucosal surfaces, triggering an intense neutrophilic inflammatory response. This leads to the classic purulent exudate. It can ascend to the upper reproductive tract, causing salpingitis and Fitz-Hugh-Curtis syndrome.
Clinical Manifestations
Men typically present with profuse, yellow-green urethral discharge and dysuria. Women often present with cervicitis, intermenstrual bleeding, or are asymptomatic. Red flags include acute pelvic pain, fever, and joint pain indicating disseminated infection.
Diagnosis
Nucleic acid amplification test (NAAT) is the gold standard for sensitivity and specificity. Gram stain showing intracellular gram-negative diplococci is diagnostic in symptomatic men. Always screen for co-infection with Chlamydia trachomatis.
Treatment
Administer Ceftriaxone 500 mg IM as a single dose for uncomplicated urogenital infection. If chlamydia is not excluded, add Doxycycline 100 mg BID for 7 days. Avoid fluoroquinolones due to high rates of resistance.
Prognosis
Untreated infection leads to PID, ectopic pregnancy, and tubal factor infertility. Patients must be abstinent for 7 days post-treatment and partners must be treated to prevent reinfection.
Differential Diagnosis
Chlamydia: typically presents with clear/mucoid discharge
Trichomoniasis: presents with frothy, yellow-green discharge and strawberry cervix
Bacterial Vaginosis: presents with thin, gray discharge and clue cells
Herpes Simplex: presents with painful vesicles and ulcerations
Non-gonococcal urethritis: often caused by Mycoplasma genitalium