Gay man, 40, develops arthritis after catching a STI

A 40-year-old gay man has developed arthritis after catching a sexually-transmitted infection through anal sex, a case report reveals.

The English patient, whose identity is unknown, was diagnosed with reactive arthritis – which caused severe pain in his joints.

Tests revealed he caught shigella flexineri, which causes diarrhoea and is found in infected faeces. It can be passed through food or sex.

Doctors at Leeds General Infirmary, who treated the patient and reported the strange case, said this was responsible for his agony.

They explained how the man often risked his sexual health by having unprotected anal intercourse – despite already having HIV.

They also said he frequently was involved in chemsex – the act of making love under the influence of illegal drugs, such as crystal meth.

The 40-year-old gay man, believed to be from Leeds, developed reactive arthritis after catching Shigella flexineri through anal sex, a case report reveals (stock image)

Following the diagnosis, the patient was counselled on safe sex and told to avoid having intercourse until his symptoms cleared.

The first documented case of reactive arthritis secondary to an STI was published in the Oxford Medical Case Reports journal.

But ‘this may not represent rarity of the condition but rather lack of realisation that Shigella can be sexually acquired’, they said.

Medics, led by Dr Sarah Kennedy, revealed how the man already had HIV – but had managed to control the potentially deadly condition.

Writing in the journal, the doctors revealed that the patient will ‘remain under regular rheumatology follow-up’.

Reactive arthritis: The facts 

Reactive arthritis causes painful joint swelling and often clears up within six months, unlike others form of the agonising condition.

It can strike anyone, but is more likely to affect those deemed to be at a genetic risk, according to Arthritis Research UK. 


The unnamed man developed reactive arthritis – considered to be a short-lived form of the agonising condition.

This can be caused by an infection, including an STI, which reacts badly on the immune system, medical literature states.

Inflammation (the swelling of the tissue) happens when the body fights off a bug – but it can trigger the process in the wrong area of the body and lead to reactive arthritis.

The exact cause remains a mystery, but scientists believe it stems from the immune system reacting to an infection – such as shigella. 

Chlamydia and gonorrhoea are often linked to the condition, due to literature stating STIs can trigger the short-lived condition. 

What is shigella? 

Shigella flexneri often leads to shigellosis – the most common type of dysentery in the UK, according to the NHS.

The Terrence Higgins Trust warns that it is possible for shigella bacteria to be passed through anal sex, among other contact methods.

‘Only a tiny amount [of the bacteria] needs to get into your mouth to pass it on,’ the sexual health charity states on its website.

Chemsex warnings 

The bizarre case comes amid repeated warnings from concerned health officials that chemsex is fueling a rapid rise in cases of STIs.

Sex during the illegal drug-fuelled sessions is often unprotected – with those having chemsex reporting an average five sexual partners per session.

Drugs such as GHB, GBL and crystal meth help to enhance sexual pleasure and reduce inhibitions, according to literature.