A 35-year-old Turkish man presents to accident and emergency with painful erythematous sclera and blurred vision of his right eye. He has had something similar in the past however it was not painful and resolved without treatment. 

He also describes 3 episodes of self-terminating painful oral and genital ulcers in the past year and ongoing bilateral arthralgia in his proximal joints.


Observations are normal. On examination, he has a globally erythematous right sclera. Vision is 6/12 in right, 6/6 in left (baseline 6/6 bilaterally). He has four well-circumscribed aphthous ulcers in his oral cavity and two further ulcers on the glans and shaft of his penis.

What is the most likely diagnosis?

Options:
explanation: Reactive arthritis is an RF-seronegative, HLA-B27-linked inflammatory arthritis that develops in response to a recent infection. It usually develops following gastrointestinal infections such as _Salmonella_, _Shigella_, or _Campylobacter_ or genitourinary infections such as _Chlamydia trachomatis_. It also presents in ages 20-40 and predominantly in males but is characterised by large joint asymmetric inflammatory oligoarthritis, conjunctivitis/uveitis, and urethritis/cervicitis (can't see, pee, or climb a tree). This patient does not complain of dysuria or symptoms of urethritis and so Behçet's disease is more likely. While reactive arthritis can occasionally cause recurrent aphthous ulcers, on balance the patient's symptoms are more in keeping with Behçet's disease
name: Reactive arthritis
label: b
answer: no
explanation: HIV Seroconversion presents 3-12 weeks following initial infection. It presents with a mononucleosis-like illness with symptoms including fever, malaise, lethargy, myalgia, lymphadenopathy, pharyngitis, painful oral/genital ulcers, and/or non-pruritic maculopapular rash. It very rarely presents with anterior uveitis and would not present with on-and-off self-resolving ulcers over 12 months
name: HIV seroconversion
label: c
answer: no
explanation: Behçet's disease is a systemic disorder of recurrent acute inflammation. It affects multiple organs, although is primarily characterised by oral ulcers, recurrent genital ulcers (which disappear and recur spontaneously), and anterior uveitis. It can also effect other organ systemic including skin, pulmonary, vascular, gastrointestinal, musculoskeletal, and central nervous systems. It is most common in ages 20-40, predominantly in males, and has greatest prevalence in Eastern Asia and the Mediterranean. There are no specific tests for Behçet's disease although HLA-B51 is the most strongly associated known genetic factor. In this question the patient is describing anterior uveitis, oral and genital ulcers, and arthralgia and so Behçet's disease is the most likely diagnosis
name: Behçet's disease
label: a
answer: yes
explanation: Syphilis can present with a wide array of symptoms . Primary syphilis presents with a painless genital ulcer (chancre) and local non-tender lymphadenopathy. It can present with painless oral ulcers although this is less common. Secondary syphilis occurs 4-10 weeks after infection and manifests with a non-pruritic rough red/reddish-brown papular rash, typically on the trunk, and flu-like symptoms such as pyrexia, pharyngitis, malaise, arthalgia/myalgia, lymphadenopathy, and headache. There are a wide variety of rare manifestations, hence the nickname "the great imitator", including uveitis, hepatitis, meningitis, glomerulonephritis, periostitis, cranial nerve palsies, and patchy alopecia. The patient in this question does not have any flu-like symptoms or lymphadenopathy and his ulcers are painful, making secondary syphilis less likely
name: Secondary syphilis
label: e
answer: no
explanation: Reactive arthritis is an RF-seronegative, HLA-B27-linked inflammatory arthritis that develops in response to a recent infection. It usually develops following gastrointestinal infections such as _Salmonella_, _Shigella_, or _Campylobacter_ or genitourinary infections such as _Chlamydia trachomatis_. It also presents in ages 20-40 and predominantly in males but is characterised by large joint asymmetric inflammatory oligoarthritis, conjunctivitis/uveitis, and urethritis/cervicitis (can't see, pee, or climb a tree). This patient does not complain of dysuria or symptoms of urethritis and so Behçet's disease is more likely. While reactive arthritis can occasionally cause recurrent aphthous ulcers, on balance the patient's symptoms are more in keeping with Behçet's disease
name: Malaria
label: d
answer: no

Correct answer: a

Behçet's disease

Learning point: Behçet's disease is an autoimmune disorder characterized by recurrent, painful oral and genital ulcers, anterior uveitis, and systemic inflammation