Gonococcal arthritis is one of the several types of infection caused by Neisseria gonorrhoeae, a Gram-negative diplococcus. It is one of the most prevalent sexually transmitted diseases (STDs) worldwide, and the leading cause of septic arthritis. Asymmetric polyarthralgia preceded or accompanied by fever and subsequent swelling of one or two joints is the typical clinical presentation. Aspiration of synovial fluid and subsequent microbiological testing is necessary to make the diagnosis.
Gonorrhea is one of the most commonly encountered sexually transmitted diseases (STDs) worldwide and is most frequently diagnosed in younger sexually active males and females    . Humans are the only known host of Neisseria gonorrhoeae, and transmission through a sexual intercourse with an infected individual (who is often asymptomatic) is the mode of infection  . After the development of a localized infection (urethritis, cervicitis, pharyngitis etc.), bacterial spread through the blood stream can cause a disseminated gonococcal infection (DGI), and gonococcal arthritis is one of the manifestations  . Risk factors for this complication include multiple sexual partners, intravenous drug use, pregnancy, menstruation at the time of infection, immunosuppression caused by human immunodeficiency virus (HIV) infection, systemic lupus erythematosus (SLE), or complement deficiency, but also African American ancestry   . Gonorrhea is the most common cause of septic arthritis in young adults, and the initial signs and symptoms of gonococcal arthritis are fever, chills, and asymmetric polyarthralgia involving the knees, ankles, and elbows     . In addition, tenosynovitis, most commonly involving the smaller extensor tendons of the hand and feet, is seen in 50-60% of cases  . However, this stage may be completely absent in some patients, and immediate progression to the suppurative stage of gonococcal arthritis, characterized by a joint swelling and arthritis of only one or two joints (known as septic arthritis), can be observed   . The knee, the wrist, the ankle and sometimes the elbow exhibit such changes in most cases . Because gonococcal arthritis stems from DGI, other manifestations, such as dermatitis, and in rare cases, endocarditis and meningitis, might concomitantly develop  .
Having in mind the specific features and the evident risk factors of this STD, the diagnosis of arthritis caused by Neisseria gonorrhoeae can be made after a thorough clinical workup. A detailed patient history is the first step, which will assess the course and progression of symptoms and identify if any of the mentioned risk factors are present, meaning that an assessment of prior sexual contacts is necessary. Secondly, if a complete physical examination reveals joint-related changes, sufficient evidence are obtained to make a presumptive diagnosis. Microbiological studies are the cornerstone in confirming Neisseria gonorrhoeae as the underlying cause of arthritis, and blood cultures, as well as Gram staining of the obtained samples, yield a very good rate of identification     . Additionally, the introduction of more advanced methods, such as the nucleic acid amplification test (NAAT), have shown to be even better compared to blood cultures  . Aspiration of synovial fluid can be performed in patients who present with evident signs of arthritis, which will reveal an inflammatory white blood cell count (10 000 to 100 000 cells/mm3), while the inoculation of aspirated fluid onto specific media for cultivation often confirm the presence of Neisseria gonorrhoeae in the setting of negative blood cultures  . Because patients are highly likely to suffer from some other STD in addition to gonorrhea, a complete STD panel testing is recommended.