While infectious agents are the most common cause, a genital ulcer may also be the result of non-infectious causes such as Behcets syndrome, lupus, or psoriasis.Since it is difficult to determine a cause of a genital ulcer from history, examination, and population characteristics alone, further testing is often needed. The most common diagnostic tools used are targeted towards the most common etiologies of genital ulcers: syphilis (syphilis serology, PCR testing, or dark-field examination), herpes simplex virus (PCR, culture, or type specific HSV antibodies), and haemophilus ducreyi (culture on special media currently not widely available in most hospital systems) if the individual is in a known endemic region. Further diagnostic tools such as a biopsy or culture are often utilized if ulcers appear unusual or do not respond as expected to therapy.Since genital ulcers are often infectious in origin, there is an increased risk of acquiring HIV in a HIV negative patient through viral introduction through the open sore Conversely, there is an increased risk of HIV transmission through increased shedding of viral HIV in the presence of a genital ulcer in a patient with a history of HIV. The CDC recommends testing for HIV in any individual presenting for a genital ulcer who does not already have a history of HIV.
The role of surgery in AIN syndrome remains controversial. Indications for considering surgery include a known space-occupying lesion that is compressing the nerve (a mass) or fascial compression, and persistent symptoms beyond 1 year of conservative treatment. Symptoms and signs
Patients may experience poorly localised, transient pain in the wrist, i.e. where the sensory branch of the AIN is mapped in the brain. The pain is sometimes referred into the cubital fossa and elbow pain has been reported as being a primary complaint.⁠
The characteristic severe impairment of the pincer movement of the thumb and index finger is most striking. Clinical signs
In a pure lesion of the anterior interosseous nerve there is weakness of the long flexor muscle of the thumb (Flexor pollicis longus), the deep flexor muscles of the index  and middle fingers (Flexor digitorum profundus I & II), and the pronator quadratus muscle.There is no sensory deficit since the anterior interosseous nerve has no cutaneous branch to skin, but there is a large sensory branch to the volar carpus, and transient wrist pain may be experienced.