One of the rare diseases to affect humans is Hughes - Stovin Syndrome (HSS), an ailment with no specific cause, affecting pulmonary vessels of the body.
It was established as a rare autoimmune disorder and a scarce variant of Behcet's disease by John Patterson Hughes and Peter George Stovin in 1959.
Etiology and Pathogenesis
The exact cause is unknown, but it is present mainly in young males between their second and fourth decade of life. The possibility of infections and angiodysplasia (a debatable theory that due to occlusion of the pulmonary artery, there is increased flow and pressure in the bronchial arteries) have been discussed across various researches.
It is mainly characterised by multiple pulmonary aneurysms, bronchial aneurysms, and peripheral venous thrombosis, occurring together or rarely as separate incidents.
According to NCBI, there are three stages before the disease progresses to death.
STAGE 1 - Thrombophlebitis signs and symptoms
STAGE 2 - Formation and expansion of pulmonary artery aneurysm
STAGE 3 - Aneurysmal rupture with massive hemoptysis, leading to death
The thrombosis pathogenesis is unclear; the plausibility ranges from Hyperhomocyteinemia's causes to the contribution of prothrombin genetic defects. But one notable merit is that the clot formed in the pulmonary arteries is primarily due to arterial vasculitis rather than venous thromboembolism.
The condition till date has not been found to have any genetic basis or familial predisposition.
Symptoms of HSS
The similarity between Behcet's and Hughes - Stovin Syndrome (HSS) makes it difficult to differentiate them. The individual may present with one or the following signs and symptoms.
- Cough
- Hemoptysis
- Fever
- Chills
- Dyspnoea
- Chest pain
Clinical findings
- Venous thrombosis
- Pulmonary hypertension
- Intracranial hypertension
- Papilledema
Secondary symptoms
The secondary symptoms are caused by increased intracranial hypertension.
- Seizures
- Diplopia
- Cephalalgia
Diagnosis of HSS
It is mainly diagnosed by ruling out Behcet'sBehcet's disease. Their radiological features are similar.
- Bronchoscopy
- Ventilation - perfusion scan
- Doppler ultrasound extremities
- CT Angiography - Both conventional and contrast are considered
- Magnetic resonance angiography
Management of HSS
There is no specific gold standard treatment for Hughes stovin syndrome. The widely used treatment modalities are
- Immunosuppressive therapy is a method of treatment that reduces immune system activity.
- Anticoagulants and thrombolytic agents are controversial as there is a risk of fatal hemoptysis.
- Arterial embolisation
- Surgical resection
Surgical management
- Pneumectomy or lobectomy - to remove aneurysms.
- Resection of pulmonary artery aneurysm with the reconstruction of the arterial segment using saphenous vein graft.
- After surgery, there is a 25% risk of recurrence of aneurysms at the site of anastomosis.
Complication of HSS
- After surgical intervention, there might be a formation of pseudoaneurysms (if arterial involvement) and false anastomotic aneurysms (if venous involvement).
- Transcatheter arterial embolisation (TAE)
- Done in patients where surgery is not recommended
- Done in patients with severe or recurrent hemoptysis
Complications of TAE
- Arteriovenous fistulae
- Pulmonary infarction
- Abscess formation
- Oesophageal necrosis
- Bronchial necrosis
- Spinal ischemia
Repeat embolisation: This is done in patients with recanalised or revascularised arterial lesions.
Prognosis of HSS
Venular aneurysms have a better prognosis than arterial aneurysms. Just as the saying goes - 'Early bird gets the worm" - Early diagnosis and timely intervention help with pushing the prognosis in a better direction and inducing good remission.
Conclusion
Hughes Stovin Syndrome is an exceedingly rare disorder with less than 40 medical literature cases published. It causes high morbidity and mortality rates if not diagnosed and treated on time. The use of Combined immuno-modulators in treating individuals gives almost favourable outcomes.
