Behçet’s Disease in Paediatrics: A Guide for MRCPCH Exams
Behçet’s disease (BD) is a rare, chronic, multi-system inflammatory condition. It is a vasculitis, meaning it causes inflammation of blood vessels of all sizes (arteries and veins). While most common in young adults, it can present in childhood, where it often has a more severe course, especially in boys. It’s a key topic for MRCPCH as it’s a differential for recurrent fever syndromes and a cause of complex multi-system disease.
Clinical Features
BD has a relapsing-remitting course and is diagnosed clinically based on a combination of symptoms. The classical triad is recurrent oral ulcers, genital ulcers, and ocular involvement (e.g., uveitis). In paediatric patients, oral ulcers are often the most common presenting symptom.
Key features to remember for the exams:
Mucocutaneous:
Recurrent oral aphthous ulcers: The most common feature. They are often multiple, painful, and can involve any part of the mouth or pharynx.
Genital ulcers: Painful ulcers on the scrotum or vulva that often scar. Less common in children than adults, but a key diagnostic criterion.
Skin lesions: May include erythema nodosum, papulopustular lesions, or acne-like lesions, particularly after puberty.
Ocular:
Uveitis: Anterior, posterior, or panuveitis is a major cause of morbidity. Posterior uveitis and retinal vasculitis are particularly serious as they can lead to permanent visual loss. Ocular involvement is more common and severe in boys.
Musculoskeletal:
Non-erosive arthritis/arthralgia: Often affects large joints (knees, ankles) and is usually self-limiting and doesn’t cause joint damage.
Gastrointestinal:
Abdominal pain, diarrhoea, and bleeding: GI involvement is more common in paediatric cases than in adults and can mimic inflammatory bowel disease (IBD). It may lead to severe complications like bowel perforation.
Neurological:
Meningoencephalitis, venous sinus thrombosis, headaches, and seizures: Neuro-Behçet’s is a serious complication that can result in long-term neurological deficits.
Vascular:
Thrombosis: Can affect both superficial veins (e.g., thrombophlebitis) and deep veins (e.g., DVT). Arterial involvement (aneurysms) is a life-threatening complication.
Diagnosis and Investigations
There is no single diagnostic test for Behçet’s disease. Diagnosis is clinical, based on the presence of a set of criteria.
Pathergy Test: A non-specific skin hyper-reactivity test. A sterile needle is used to prick the skin, and a positive result is the development of a papule or pustule at the site within 24-48 hours.
Laboratory Tests: No specific markers, but blood tests may show non-specific inflammation (elevated ESR, CRP). HLA-B51 is a genetic marker associated with BD, but it is not essential for diagnosis.
Imaging: May be used to investigate specific organ involvement, such as brain imaging for neurological symptoms or angiography for vascular disease.
A common pitfall in paediatric practice is the delay in diagnosis because symptoms may present in a different order or the full clinical picture may take years to develop.
Management
Management is multidisciplinary and tailored to the organ system affected and the severity of the disease. There is no cure, so the goal is to control inflammation and prevent organ damage.
Topical therapies: Steroid mouthwashes or gels for oral ulcers.
Colchicine: Can be effective for mucocutaneous and joint symptoms.
Systemic immunosuppressants:
Corticosteroids: Used for acute flares, especially those involving the eyes or CNS.
Azathioprine, Methotrexate, Cyclophosphamide: Used as steroid-sparing agents for long-term disease control.
Biological therapies:
TNF-alpha inhibitors (e.g., Infliximab, Adalimumab): Often used for severe disease, especially with ocular, CNS, or GI involvement, which is refractory to conventional immunosuppressants.
Prognosis is variable, but the disease can cause significant morbidity, particularly from irreversible eye damage and neurological or vascular complications. The prognosis is generally worse for males and those with early-onset disease.