Right hip gonococcal septic arthritis treatment with successful transition to oral fluoroquinolone

Abstract

We present a case of gonococcal septic arthritis of the right hip diagnosed via synovial fluid cultures. Antimicrobial susceptibility testing of the synovial fluid demonstrated susceptibility to tetracycline, ciprofloxacin, cefixime and ceftriaxone. Our patient was initially treated with ceftriaxone and was successfully de-escalated to oral levofloxacin to complete the treatment. This case is interesting given the rarity of disseminated gonococcal infections in the 21st century and that most clinical isolates of Neisseria gonorrhoeae are increasingly resistant to fluoroquinolones.

Background

Neisseria gonorrhoeae is a gram-negative diplococcus that is one of the most common causes of sexually transmitted diseases. Infection primarily involves mucosal surfaces of humans, although 0.5%–3% of patients can have haematological spread leading to disseminated gonococcal infection (DGI).¹ DGI can manifest as gonococcal arthritis in two clinical syndromes: arthritis-dermatitis syndrome (60%) and localised septic arthritis (40%).² Arthritis-dermatitis syndrome consists of the triad of migratory polyarthralgia, tenosynovitis and dermatitis with a papulovesicular rash. We present a case of gonococcal right hip septic arthritis that was successfully treated with an oral fluoroquinolone after receiving a few days of intravenous ceftriaxone.

Case presentation

A man in his 50s with a medical history of chronic pancreatitis, hypertension, alcohol use disorder and homelessness presented to the emergency department (ED) with a chief complaint of right hip pain for the past 3 days. He was unable to ambulate due to the pain prompting him to seek medical attention. He was admitted with a history of dysuria, haematuria and white penile discharge for the past month. He denied fevers, back pain, numbness, weakness, oedema or other joint pain. His last reported sexual intercourse was 8–12 months ago. He denied oral, anal or vaginal penetration since that time. On admission, the patient was afebrile and haemodynamically stable. The physical examination consisted of right hip tenderness, oedema and decreased range of motion limited by pain. The remainder of the physical examination was unremarkable.

The patient was evaluated at another healthcare facility the day prior and was diagnosed with a urinary tract infection. He was discharged with a cephalexin prescription for 10 days, but he never picked up the medication. Urine collected at this visit tested positive for N. gonorrhoeae and negative for Chlamydia trachomatis by nucleic acid amplification tests (NAAT).

His urine culture grew 30 000 colonies/mL of N. gonorrhoeae. He did not receive treatment for N. gonorrhoeae at this time.

Investigations

Laboratory workup was significant for a white cell count of 13.33x10⁹/L, C reactive protein of 17.8 mg/L and erythrocyte sedimentation rate of 62 mm/hour. He tested negative for HIV, hepatitis viruses, syphilis and herpes simplex virus. MRI of the right hip demonstrated right iliopsoas bursitis with small right hip joint effusion (figure 1). A right hip arthrocentesis was performed with 20 mL of purulent aspirate fluid obtained. The synovial fluid had a white cell count of 61.68 10⁹/L and red cell count of 3x10¹²/L. The final blood and synovial fluid cultures demonstrated N. gonorrhoeae confirmed using VITEK 2 identification. The cultures were sent to a reference laboratory for antibiotic susceptibility and were found to be susceptible to tetracycline, cefixime, ceftriaxone and ciprofloxacin (figure 2).

Figure 1.

MRI of the right hip demonstrating periarticular oedema of the right hip joint involving the piriformis and gluteal muscles.

Figure 2.

Susceptibilities of Neisseria gonorrhoeae obtained from synovial fluid.

Differential diagnosis

Additional differential diagnoses to consider are more common causes of bacterial septic arthritis, such as Staphylococcus aureus, Streptococcus pneumoniae and other gram-negative bacteria. Our patient’s socioeconomic history of homelessness and alcohol abuse puts him at risk for infections such as HIV, hepatitis viruses and tuberculosis. It is important to rule these diagnoses out as they can all cause arthritic pain. Reactive arthritis is another differential diagnosis to consider as the patient is at a higher risk for C. trachomatis infection. Osteomyelitis should be considered in patients with a history of intravenous drug use. Crystalline arthropathies, such as gout, must be considered as excessive alcohol use can precipitate joint pain. Further differential diagnoses include osteoarthritis, rheumatoid arthritis, septic bursitis, avascular necrosis, Lyme disease and acute traumatic arthritis.

Treatment

The patient was diagnosed with right hip gonococcal septic arthritis. Orthopaedic surgery recommended non-operative treatment. He initially received intravenous ceftriaxone 2 g per day for 5 days. After antimicrobial susceptibilities resulted, he was transitioned to levofloxacin 750 mg to complete 3 weeks of therapy.

Outcome and follow-up

The patient received inpatient care for 1 week, given the need for intravenous therapy and severe right hip pain preventing him from ambulating independently. After working with physical therapy, he had clinical improvement and could perform activities of daily living with minimal pain. The patient was intended to follow-up with an infectious disease physician at an outpatient sexually transmitted disease clinic; however, he did not show up for his appointment. The patient returned to the ED a few months after the initial encounter for another complaint, and he had no complaints of right hip pain or gait abnormalities.

Discussion

Localised gonococcal septic arthritis presents with purulent arthritis in one or more joints, typically without systemic symptoms.² Knees, ankles, wrists and finger joints are commonly affected, while infection of the hip joint is surprisingly rare.^{3 4} In the 1970s, gonococcal infections in the USA were at an all-time high with 468 per 100 000 population.^{3 5} Gonococcal arthritis was a leading cause of septic arthritis in young adults during that time. Since then, the annual incidence of gonococcal infections decreased in countries with easy access to healthcare and effective public health programmes, leading to a historically low number of cases in 2009.³ However, according to the Center for Disease Control and Prevention (CDC), reported gonorrhea cases have increased by 111% from 2009 to 2020.⁶ Furthermore, a retrospective study in France reported a recent increase in DGI with joint involvement becoming more prevalent.⁷

Gonococcal arthritis is diagnosed with a positive culture yielding N. gonorrhoeae; however, culturing this organism can be difficult. This bacterium is known for its fragility and requires a specialised media for optimal growth.⁸ N. gonorrhoeae is isolated in 50% of blood and synovial fluid cultures, while mucosal swab cultures are positive in 80% of cases of gonococcal arthritis.⁸ When cultures are negative and clinical suspicion is high, NAAT can be performed to help identify N. gonorrhoeae. NAAT of the synovial fluid is more sensitive than cultures with a sensitivity of 80%.³ Although NAAT is an excellent tool due to its sensitivity, it has limitations as it does not provide testing for antibiotic resistance. It is essential to always obtain cultures from all possible sites to obtain drug susceptibilities and guide management.

N. gonorrhoeae has been progressively developing antibiotic resistance since the 1940s; most isolates today are resistant to penicillin, tetracyclines, fluoroquinolones and sulfonamides.⁹ The current recommended regimen for gonococcal arthritis is ceftriaxone 1 gram intramuscular or intravenous every 24 hours for at least 7 days. Alternative recommended regimens include cefotaxime or ceftizoxime 1 g every 8 hours.¹⁰ If chlamydia infection has not been excluded, doxycycline or azithromycin is added for possible coinfection. After demonstrating clinical improvement with standard therapy, transitioning to oral antibiotics to complete treatment can be considered only in patients with culture-proven susceptibilities.¹⁰ Duration of therapy is guided by clinical presentation, susceptibilities and comorbidities.

While ceftriaxone remains first line treatment, there have been cases with reduced susceptibility to cephalosporins.⁹ In 2011, Ohnishi et al reported the first case of ceftriaxone-resistant N. gonorrhoeae in Japan.¹¹ Since then, there have been cases of ceftriaxone-resistant strains in Canada and evidence of international spread of the penA gene allele associated with the resistance.^{12 13} Although most N. gonorrhoeae strains in the USA are highly sensitive to ceftriaxone, it is important to be aware of these resistant strains and to test all cultures for antimicrobial susceptibilities as complementary antibiotics could be more effective. It is imperative to treat DGI appropriately to reduce morbidity and complications such as permanent joint damage, endocarditis, meningitis, perihepatitis and osteomyelitis.¹⁴

This case highlights a rare presentation of gonococcal septic arthritis of the hip. Our goal is to increase awareness of completing treatment of gonococcal arthritis with oral antibiotics given susceptibilities after receiving first line treatment with intravenous ceftriaxone. With the increasing number of gonococcal infections and resistant patterns, it is essential to have a high clinical suspicion for gonococcal arthritis in sexually active adults presenting with joint pain or swelling.

Learning points.

• Disseminated gonococcal infection is rare, but recent reports have shown an increase in cases.

• This is a case of right hip gonococcal septic arthritis first treated with ceftriaxone that was successfully transitioned to an oral fluoroquinolone to complete treatment. This is unique as most clinical isolates of Neisseria gonorrhoeae are resistant to fluoroquinolones.⁹

• Antimicrobial resistance is becoming a more considerable burden with the limited antibiotic arsenal.

• It is important to obtain cultures with antimicrobial susceptibilities in all cases of suspected gonococcal septic arthritis to ensure appropriate treatment and prevent further antibiotic resistance.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).