Gonococcal Arthritis

Gonococcal arthritis is caused by infection with the gram-negative diplococcus N gonorrhoeae, a highly infectious organism that exclusively infects humans; it is capable of colonizing diverse mucosal surfaces. The risk of infection from a single contact with N gonorrhoeae is estimated to be 60-90% for women and 20-50% for men. ^[1] Common sites of infection include the urethra, cervix, pharynx, and rectum. Infection may be asymptomatic in some patients.

There have been reports of gonococcal arthritis in toddlers and young children. Sexual abuse should be considered as a possible cause of the infection in pediatric cases. ^[3]

Hematogenous spread of the mucosal infection occurs in 0.5-3% of cases, ^[4] and disseminated infection is thought to play a major role in the pathogenesis of gonococcal arthritis. Patients with DGI may present with dermatitis-arthritis syndrome (60% of cases) or with a localized septic arthritis (40%). These presentations may represent different phases of a disease continuum.

The risk of dissemination after mucosal infection depends on both the ability of the patient’s immune system to control the infection and the virulence of the organism. Factors that correlate with an increase in this risk have been identified for both the host and the organism. Host-related risk factors for disseminated infection include the following ^[2] :

• Female sex
• Pregnancy
• Menses
• Systemic lupus erythematosus
• Complement deficiency
• Low socioeconomic or educational status
• Intravenous drug use
• HIV infection
• Multiple sexual partners

Organism-related risk factors for DGI include the following ^{[1, 2, 4, 5]} :

• Antigenic variation of pili
• Protein Por B _1A on the outer membrane – This inhibits host factor H and C4-binding protein, making host complement cascade less effective
• Lack of protein Por B _1B
• Strains with nutritional requirements for arginine, hypoxanthine, and uracil (ie, AHU strains) – These are often associated with protein IA
• Colony opacity (Opa) protein-independent invasion - Opa proteins are adhesins crucial to the process of N gonorrhoeae attachment to host cells, particularly avoidance of carcinoembryonic antigen–related cell adhesion molecule-3 (CEACAM3) ^[6]

Gonococcal arthritis is a clinical manifestation of disseminated gonococcal infection, which develops in approximately 0.5-3% of individuals who are infected with N gonorrhoeae. ^[2]

United States statistics

According to the Centers for Disease Control and Prevention (CDC), gonorrhea is the second most commonly reported notifiable sexually transmitted disease in the United States (after Chlamydia infection), with 710,151 cases reported in 2021. ^[5]

The rate of reported gonorrhea cases in the US declined from their peak of 467.7 cases per 100,000 population in 1975 to an historic low of 98.1 cases per 100,000 population in 2009, and since then have risen 118%. In 2020-2021, the overall rate of reported gonorrhea increased 4.6%. As of 2021, the national rate of gonococcal infection was 214 cases per 100,000 population. ^[5] Within the United States, however, rates of infection vary by region (highest in the South and lowest in New England) and by demographics (see below).

International statistics

The World Health Organization (WHO) estimates that 82 million cases of gonococcal infection occurred in 2020. ^[7] Gonococcal infection is common in developing countries, partly because of limited public health infrastructure and limited access to health care.

A 3-year retrospective study from France of 21 cases of disseminated gonococcal infection, which included 14 cases of arthritis, found that the number of cases increased from to 2009 to 2011. Men were at higher risk than women. ^[8] In a study of indigenous people in central Australia, the incidence of gonococcal arthritis was 911 of 100,000 gonococcal notifications. Cases were significantly more likely to occur in young (≤29 years) indigenous women than young indigenous men; risk was almost twice as high in women than in men. ^[9]

Age-, sex-, and race-related demographics

In the United States, the highest rates of gonorrheal infection are in persons aged 20-24 years. However, rates are also high in those ages 25-29. In addition, during 2021 the gonorrhea rate increased in all age groups.  The rates per 100,000 population by age group are as follows ^[5] :

• Age 15–19 years: 472.6 
• Age 20–24 years: 860.5
• Age 25–29 years: 661.5
• Age 30–34 years: 473.5
• Age 35–39 years: 390.9
• Age 40–44 years: 183.0 

In 2021, the rate of reported gonorrhea cases was higher in men than in women (249.7 versus 177.9 cases per 100,000, respectively).  Rates in women fell in 2012-2014, from 107.9 to 100.4 per 100,000, but have been rising since then; rates in men have increased steadily since 2012, when the rate was 105.0 per 100,000. ^[5]

Gonococcal infection is most common in African Americans. ^[5] Cases per 100,000 by race/ethnicity were as follows in 2021:

• Blacks -  652.9
• American Indians/Alaska Natives - 370.9
• Native Hawaiians/Other Pacific Islanders - 204.9
• Multirace persons - 162.2
• Hispanics/Latinos - 137.0
• Whites - 78.9
• Asians - 37.8

For patients with septic arthritis resulting from gonococcal infection, proper antibiotic treatment and joint drainage typically leads to full recovery. For patients with more severe manifestations of DGI, the prognosis varies, depending on complications or comorbidities. For example, patients with acute endocarditis may require valve surgery and can expect to undergo at least 4-6 weeks of antibiotic therapy. DGI-associated morbidity has decreased dramatically in the antibiotic era. Complications are rare (1-3% of cases). ^[1]

Patient education is an integral part of proper therapy. Patients should learn about the sexual transmission of the disease and be informed regarding barrier methods of preventing it (condoms). In addition, education regarding specific risk factors or high-risk behaviors may help prevent further gonococcal infections or more severe sexually transmitted diseases (eg, HIV infection). Also important are identification, examination, and treatment of patients’ sexual partners.

For patient education resources, see the Sexual Health Center and the Arthritis Center, as well as Gonorrhea and Sexually Transmitted Diseases.