Dr. med. Dirk Manski

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Gonorrhea: Pathogen and Symptoms of the gonococcal Urethritis

Definition of Gonorrhea

Gonorrheal urethritis (GU) with purulent urethral discharge is a venereal disease caused by Neisseria gonorrhoeae. Gonorrhea is derived from an old Greek word meaning ‘flow of seed [semen]’.

Epidemiology of Gonorrhea

USA 114/100.000 new cases (in 2004), rising to nearly 200/100.000 (in 2021). Much lower figures in Europe, e.g., Germany 21/100.000 (in 2017).

Etiology of Gonorrhea

Bacterial pathogen:

Neisseria gonorrhoeae. Strictly aerobic. Unencapsulated.

Morphology of Gonococcus:

gram-negative diplococci with a diameter of about 1 micron (coffee bean-shaped). Frequently intracellular in granulocytes [fig. gonorrhea (microscopy)].

microscopy of urethral discharge due to Gonorrhea (urethritis)
Fig. gonorrhea: schematic drawing of the microscopic finding of urethral discharge. Neisseria gonorrhoeae are gram-negative diplococci (coffee bean-shaped), often intracellular in granulocytes. Figure from Dr. Norman Jacobs, Public Health Image Library, Center for Disease Control and Prevention, USA, https://phil.cdc.gov/.

Virulence factors:

There are pili for the attachment to human epithelial cells and secretion of proteins as virulence factors: porins, IgA-ase, and penicillinase. The contact of gonococci leads to endocytosis and basal exocytosis. This results in an infection of the urethral lamina propria.

Transmission of gonorrhea:

Gonorrhoea is a mucus membrane infection due to vaginal, oral or anal sexual contact. The risk of infection per intercourse for men is around 17%. Rare transmission occurs through birth or as aerosol infection (conjunctivitis). Humans are the only reservoir for Neisseria gonorrhoeae.

Gonorrhea: Signs and Symptoms


The incubation period is 3–10 days, with a significant variance depending on the bacterial strain. Typical symptoms are purulent discharge from the urethra, dysuria, pain in the urethra, and inguinal lymphadenopathy. The extent of the symptoms is variable; women experience fewer symptoms than men.

Extragenital Infections:

Proctitis or pharyngitis causes only minor or no symptoms; these are relevant bacterial reservoirs. Conjunctivitis (ophthalmia neonatorum) is typical for neonates [fig. neonatal conjunctivitis]. Seldom arthritis or gonococcal sepsis.

Complications of Gonorrhea

Complications in men:

Acute prostatitis, epididymitis, urethral strictures, and infertility.

Complications in women:

Bartholinitis, cervical endometritis, pelvic inflammatory disease, and infertility.

Fitz-Hugh-Curtis syndrome:

Fitz-Hugh-Curtis syndrome is an ascending pelvic inflammatory disease with peritoneal infection. Typical is right-sided abdominal pain due to infection of the hepatic peritoneum (perihepatitis).

Reiter syndrome:

Due to a mixed infection with Chlamydia, the Reiter syndrome can also be possible in gonorrhea. See also chapter non-gonococcal urethritis.

Index: 1–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


CDC Guidelines: gonococcal infections in adolescents and adults. https://www.cdc.gov/std/treatment-guidelines/gonorrhea-adults.htm

EAU Guidelines "Urological Infections,” Available: https://uroweb.org/guidelines/urological-infections/.

IUSTI, Unemo et al.: European Guideline on the Diagnosis and Treatment of Gonorrhoea in Adults (2020). https://iusti.org/wp-content/uploads/2020/10/IUSTI-Gonorrhoea-2020.pdf

DSTIG, DGU, and RKI, “Diagnostik und Therapie der Gonorrhoe. AWMF S2k-Leitlinie,” 2018. [Online]. Available: https://www.awmf.org/uploads/tx_szleitlinien/059-004l_S2k_Gonorrhoe-Diagnostik-Therapie_2019-03.pdf.

Robert-Koch-Institut, “Gonorrhoe (Tripper): RKI Ratgeber,” 2023. [Online]. Available: https://www.rki.de/DE/Content/Infekt/EpidBull/Merkblaetter/Ratgeber_Gonorrhoe.html.

  Deutsche Version: Gonorrhoe: Erreger und Klinik gonorrhoischen Urethritis.