Reactive Arthritis

Reactive arthritis, known as Reiter’s syndrome, is an inflammatory disease [1] of the joints following an infection. This is commonly triggered by a genito-urinary infection or gastroenteritis. The onset of joint swelling, aches and pains tend to occur 1 to 3 weeks following an infection that you may not be aware of.

The condition is slightly more common in men but can also affect women.

Although reactive arthritis is uncommon, we occasionally encounter the condition in primary care. This article serves to increase awareness of the medical condition and encourage patients to reach out early for appropriate medical treatment.

What are the symptoms of reactive arthritis?

The classic triad symptoms of reactive arthritis include:

Arthritis

• Affected joints [2] may present with aches, pains and swelling. This can occur over the larger joints, such as knee joints or smaller joints, such as the fingers and feet, wrist, elbow, or ankles.
• Commonly, the affected joints are from the lower part of the body, and the symptoms tend to present asymmetrically. 
• Lower back pain is a common presenting symptom due to the underlying inflamed lower spine.

Urethritis

• One may present with abnormal urinary symptoms such as blood in the urine, pain, burning, itching sensations during urination, and increased frequency or discomfort during urination. 
• In women, one may present with abnormal vaginal discharge and lower pelvic discomfort, suggesting cervicitis.
• In men, one may notice urinary/urethral discharge, occasionally experiencing testicular pain or swelling.

Conjunctivitis

• One may present with a red, gritty, uncomfortable – suggesting eye inflammation.

In addition to the typical triad symptoms, patients may also present with:

Enthesitis 

• Inflammation of the tendons and ligaments that connect the bone
• One may present with heel or sole pain.

Skin rash

• One may present with rashes over the feet, palms, ulcers in the mouth and tongue, and rash over the penis.

Cardiac/heart symptoms

• Rarely, one may present with chest discomfort, shortness of breath on exertion, heart murmur, or fainting spells suggesting underlying heart involvement. 

Reactive arthritis and STDs

When reactive arthritis happens due to an underlying sexually transmitted disease, it is known as sexually acquired reactive arthritis [3] (SARA). 

Reactive arthritis can be triggered following an infection of the genito-urinary system secondary to sexually transmitted [4] pathogens. STDs such as chlamydia trachomatis [5], Neisseria gonorrhoeae, mycoplasma genitalium, and ureaplasma urealyticum can cause infective urethritis and are associated with SARA. 

SARA should be considered as one of the differentials when a young patient's profile is presented with unexplained acute joint inflammatory symptoms. Sexual history should be screened, and appropriate STD tests should be offered to avoid further delay in the treatment of the disease.

While abnormal joint symptoms are seen in SARA, patients may also present with abnormal urinary symptoms such as urethral discharge, pain during urination, increased urinary frequency, and testicular pain and swelling in men. In women, one may notice abnormal vaginal discharge, spotting in between periods, spotting after sex, or painful intercourse. Those that engage in anal intercourse may present with rectal discomfort, bleeding, discharge or tenesmus (feeling of incomplete defecation).

It is imperative to consider STD testing, as STD infections will require the correct dose and antibiotics to treat (depending on the type of STD), and STDs do not resolve on their own by the immune system.

Reactive arthritis and HIV

An unexplained arthritis symptom can be an early manifestation of HIV. Also, reactive arthritis can occur in HIV patients. In these patients, the symptoms progression of reactive arthritis can be faster, and the condition can be more severe. 

HIV infection should always be screened and considered as a differential in an unexplained inflammatory arthritis symptom. 

Can a non-STD infection cause reactive arthritis?

Yes, it is possible. Non-STD infections involved in reactive arthritis include bacteria that cause gastroenteritis or dysentery (a severe form of diarrhoea). These pathogens include Salmonella spp, Shigella spp, Campylobacter jejuni, Clostridium difficile, and Yersinia enterocolitica.

Patients with non-STD-related reactive arthritis may present with a history of severe diarrhoea, abdominal discomfort, vomiting, nausea, etc.

Genetically, can I be more susceptible to reactive arthritis?

Genetically, if a person is found to carry the gene [6] HLA-B27, they are 10 times more susceptible to developing reactive arthritis following an infection. 

Human leukocyte antigens (HLAs) are proteins found on the surface of white cells. They are genetically programmed to aid the immune system to differentiate the body’s own cells and noxious external particles.

The presence of HLA-B27 can be detected through simple blood tests.

When should I see a doctor if I have concerns about reactive arthritis?

You should see a doctor if you have abnormal joint symptoms following recent diarrhoea or genital infection. If you have concerns about exposure to STDs, you should also see a doctor for further checkups and treatment.

What should I expect when I see my doctor for reactive arthritis?

Your doctor will obtain a medical history that includes your sexual history. A physical examination involving the genital region, skin surfaces, joints, eyes, and cardiac areas may be offered.

Depending on your individual presenting symptoms and risks of exposure, tests that your doctor can offer include:

• Blood tests to screen for infection, HLA-B27, and STDs
• Genital swabs and urine tests to screen for STDs
• Stool tests to screen for gastro-related infection
• X-rays to evaluate further the affected musculoskeletal region

In addition to the tests, your doctor may refer you to a rheumatologist, ophthalmologist, or even a cardiologist if there are concerns about the involvement of the disease in other organs of the body.

What treatments are available for reactive arthritis?

Treating the underlying infection with appropriate antibiotics is key in managing reactive arthritis. In the case of STDs, sexual partners should be screened and treated concurrently to reduce the risk of reinfections. 

For the management of joint symptoms, non-steroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed. In more severe conditions, steroids and immunosuppressive medications may be offered to manage the symptoms of reactive arthritis. 

What are the complications of not treating reactive arthritis?

Arthritis symptoms in this condition tend to resolve over a few months, though some patients may have recurring arthritis or long-term chronic symptoms. Chronically inflamed joints are predisposed to joint damage, leading to loss of joint function.

Those with eye inflammations that are not treated adequately may run a risk of cataracts in the future or irreversible loss of vision.

What have I learned about Reactive Arthritis?

• STDs can cause reactive arthritis.
• Reactive arthritis is associated with three key presentations – the joint, the genito-urinary system, and the eye.
• Key management is to treat the underlying infection and relieve the joint symptoms.
• STD screening and treatment are crucial in sexually acquired reactive arthritis.
• Most people do recover from the condition.

References

1. Barth WF, Segal K. Reactive arthritis (Reiter's syndrome). Am Fam Physician. 1999 Aug;60(2):499-503, 507. PMID: 10465225.
2. “Reactive Arthritis-Reactive Arthritis - Symptoms & Causes - Mayo Clinic,” Mayo Clinic, 2022, https://www.mayoclinic.org/diseases-conditions/reactive-arthritis/symptoms-causes/syc-20354838.
3. Carlin E, Flew S. Sexually acquired reactive arthritis. Clin Med (Lond). 2016 Apr;16(2):193-6. doi: 10.7861/clinmedicine.16-2-193. PMID: 27037393; PMCID: PMC4952977.
4. Rich E, Hook EW, III, Alarcón GS, Moreland LW. Reactive arthritis in patients attending an urban sexually transmitted diseases clinic. Arthr Rheum 1996;39:1172–7.
5. Taylor-Robinson D, Keat A. Observations on Chlamydia trachomatis and other microbes in reactive arthritis. Int J STD & AIDS 2015;26:139–44.
6. Colmegna I, Cuchacovich R, Espinoza LR. HLA-B27-associated reactive arthritis: pathogenetic and clinical considerations. Clin Microbiol Rev 2004;17:348–69.