Angina bullosa haemorrhagica (ABH) is a condition of the mucous membranes of the mouth (oral mucosa). Where this is usually painless and benign, blood blisters suddenly appear, usually on the soft palate at the back of the mouth. 

It was first described in 1933 as traumatic oral hemophlyctenosis, although the clinical term ABH was first coined by NJ Badham in 1967.^1,2 ABH is also known as localised oral purpura, stomatopompholyx haemorrhagica, and recurrent oral hemophlyctenosis.³ It is fairly rare (although it may be under-diagnosed), and affects primarily adults over 45 years of age, affecting people assigned male at birth (AMAB) and people assigned female at birth (AFAB) equally.^4,5 

There is usually no family history of ABH and it does not appear to be inherited, although it may be associated with type 2 diabetes and hypertension.⁵

Signs and Symptoms of ABH

A stinging pain or burning sensation may be experienced just before a blood blister between 1 and 3 cm in diameter appears. These blisters burst spontaneously within 24-48 hours, leaving a shallow ulcer that will heal without scarring or discomfort within about a week.^6,1 

In all cases described in the literature, there was no systemic disorder and all blood tests were normal.⁷ Occasionally patients may experience hoarseness or blood-tinged sialorrhea (drooling).⁶

The soft palate (back of the mouth) is the most commonly affected site, although it can occasionally occur on the buccal mucosa (cheek), on the tongue, or in the oesophagus.⁶  About 30% of patients have blisters in more than one location. If the blisters on the palate are particularly large they may need to be cut and drained (de-roofed) to eliminate the sensation of choking and any acute upper airway obstruction.⁸

Causes of ABH

Why ABH occurs in some people but not others is not well understood, however, a looser cohesion between the layers of cells in the mouth mucosa and exaggerated susceptibility to trauma may predispose some people to ABH.^9,10,6 Causes of ABH are various but about half of the cases are related to minor mouth trauma from, for example, hot or sharp foods, dentistry such as rough fillings or periodontal therapy for gum disease.⁴ 

Anaesthetic dental injections in the mouth may also cause ABH. There is also an association between the use of corticosteroid inhalers, and NSAIDs (non-steroidal anti-inflammatory drugs, e.g., aspirin, ibuprofen) and ABH.^11,12 

Sato et al (2017) described a case of ABH in the throat (pharynx) in an inhaled corticosteroid user, apparently caused by minor pharyngeal trauma due to EGD (esophagogastroduodenoscopy), a procedure to examine the oesophagus, stomach and duodenum using a long flexible camera.¹³

Other causes of blood blisters in the mouth include:

• Oral ulcers
• Food allergy
• Nutritional deficiency particularly of vitamin B12 and vitamin C
• Prescription drugs
• Cheek biting
• Oral herpes virus

Other conditions which your doctor may want to rule out include inflammatory conditions, autoimmune, and metabolic disorders. These might include: mucous membrane pemphigoid, epidermolysis bullosa, bullous pemphigoid, dermatitis herpetiformis, lichen planus, linear IgA bullous disease and oral amyloidosis.^14-20 Click on the links above for more information on each of these conditions.

Treatment of ABH

Since the blisters normally burst and heal spontaneously, no treatment is usually required.   Blood tests may be carried out to rule out a blood disorder but the blisters are so short-lived that a biopsy (tissue sample) can rarely be taken. Any pain and discomfort may be reduced by using a benzydamine mouthwash/spray (Difflam), and chlorhexidine mouthwash (Corsodyl) may help prevent a secondary infection and therefore aid healing.

Summary

Angina bullosa haemorrhagica is a rare, idiopathic (it has no certain cause) condition of the oral mucosa where blood blisters form, usually in response to minor trauma. The condition is self-limiting, healing without scarring within a week, and only rarely requires treatment beyond local anaesthetics and soothing mouthwashes.