angina bullosa hemorrhagica is a rare benign subepithelial oral mucosal blisters filled with blood that are not attributable to a systemic disorder or haemostatic defect . angina bullosa hemorrhagica ( abh ) is a sub epithelial oral mucosal hemorrhagic blister of unknown aetiology . this condition was first described in 1933 by argentina as traumatic oral haemophlyctenosis and badham in 1967 first used the currently accepted term abh . clinically , it presents as acute , spontaneous , asymptomatic hemorrhagic vesicle / bullae , commonly on the soft palate in middle aged individuals without any sex predilection . though exact aetiology is not known , many local and systemic factors are incriminated in the causation of abh . we report two cases of abh which was idiopathic in one case and other was associated with chronic renal failure on hemodialysis . a 48-year - old woman presented with asymptomatic recurrent blood filled blister in the oral cavity with a history of irregular and intermittent appearance since 25 years . in most instances , lesion appeared singly on the lateral aspect of tongue but also involved soft palate occasionally . lesions healed spontaneously without any sequel but lesion recurred every year once or twice without any seasonal predilection . no history of intake of any other drugs , no history suggestive of precipitating factors like trauma , steroid inhalation , blood dyscrasias . not a known diabetic , hypertensive or asthamatic . , there was solitary oval tense hemorrhagic bulla measuring about 2  1.5 cm over the lateral margin of tongue on the right side [ figure 1 ] . hemorrhagic blister over lateral tongue in case 1 a 50 years old male patient with chronic renal failure since two years , on haemodialysis since 8months with blood pressure , developed hemorrhagic blister at the junction of buccal mucosa and alveolar ridge on right side . over a period of 12 hrs it ruptured discharging thin clear blood mixed fluid and healed within four days without any scarring or other squeal . on examination , there was solitary oval tense hemorrhagic bulla measuring about 2.5  2 cm present at the junction of buccal mucosa and alveolar ridge on right side . hemorrhagic blister at the junction of buccal mucosa and alveolar ridge on right side which broke on manipulation tzanck smear in both cases showed numerous rbc 's and there was no acantholytic or multi - nucleated giant cell . biopsy from case -1 of the ruptured blister revealed sub - epithelial split with minimal perivascular infiltrate . biopsy could not be done in case -2 , since the patient did not consent . routine blood and urine tests including bleeding and clotting time , liver function test , renal function test , thyroid function test , lipid profile , ultra sound examination of abdomen and pelvis , chest in case-2 , all the investigations were normal except for high blood pressure ( 130/90 mm hg ) and elevated serum urea and creatinine levels ( 50 and 2.5 mg / dl respectively ) . spontaneous onset , isolated nature , constant presence of blood in the blister fluid and rapid healing in the absence of an identifiable local cause or systemic disorder differentiates abh from mucous membrane pemphigoid , bullous pemphigoid , bullous lichen planus , epidermolysis bullosa , dermatitis herpetiformis , linear iga disease and oral amyloidosis . the classical history and morphology of lesions helped us to arrive at the clinical diagnosis of angina bullosa hemorrhagica in both the presenting cases . abh is a benign phenomenon that is characterized by the sudden appearance of a blood filled blister on the oral mucosa in the absence of an identifiable cause or systemic disorder , commonly seen in middle and elderly people with no sex predilection . bulla is typically seen on soft palate and occasionally on lateral border of tongue , gingiva and buccal mucosa . onset is rapid and blistering starts over few minutes which breaks down in minutes to hours to form shallow ulcer and heals spontaneously over 3 - 10 days . recurrences can be seen at the same or different oral site in 30% of people . local factors implicated are trauma from hot foods , dental procedures and endoscopy , local anaesthesia , and chronic steroid inhalation and systemic causes are hypertension , asthma , diabetes , rheumatoid arthritis , gastrointestinal disturbances and hyperuracemia . yamamoto et al . in his report of 11 cases , described a case of abh associated with renal failure . it has been known that abh presents with recurrences at regular intervals , usually associated with some internal disease or with some medications . in our cases reported here , case-1 had a classical presentation with pronged history of irregular presentation for 25 years without any other associated disease or drug intake . case 2 presented with a classical presentation of first episode associated with blood pressure and renal failure on dialysis . these cases are reported for the relative rarity of this entity and the diversity of presentation with reference to site within the oral cavity ( in case -1 , presenting at an atypical site ) and diverse aetiology . this report though does not convey significant new information it would certainly help to create more awareness among dermatologists and oral physicians to be able to differentiate from a host of other blistering disorders of varying aetiologies in the oral cavity . angina bullosa hemorrhagica may be seen in renal failure patients on dialysis and may have recurrence for long periods . this reprt helps to create awareness among dermatologists and oral physicians to be able to differentiate from a host of other blistering disorders of varying aetiologies in the oral cavity . a 48-year - old woman presented with asymptomatic recurrent blood filled blister in the oral cavity with a history of irregular and intermittent appearance since 25 years . in most instances , lesion appeared singly on the lateral aspect of tongue but also involved soft palate occasionally . lesions healed spontaneously without any sequel but lesion recurred every year once or twice without any seasonal predilection . no history of intake of any other drugs , no history suggestive of precipitating factors like trauma , steroid inhalation , blood dyscrasias . not a known diabetic , hypertensive or asthamatic . , there was solitary oval tense hemorrhagic bulla measuring about 2  1.5 cm over the lateral margin of tongue on the right side [ figure 1 ] . a 50 years old male patient with chronic renal failure since two years , on haemodialysis since 8months with blood pressure , developed hemorrhagic blister at the junction of buccal mucosa and alveolar ridge on right side . over a period of 12 hrs it ruptured discharging thin clear blood mixed fluid and healed within four days without any scarring or other squeal . on examination , there was solitary oval tense hemorrhagic bulla measuring about 2.5  2 cm present at the junction of buccal mucosa and alveolar ridge on right side . hemorrhagic blister at the junction of buccal mucosa and alveolar ridge on right side which broke on manipulation tzanck smear in both cases showed numerous rbc 's and there was no acantholytic or multi - nucleated giant cell . biopsy from case -1 of the ruptured blister revealed sub - epithelial split with minimal perivascular infiltrate . biopsy could not be done in case -2 , since the patient did not consent . routine blood and urine tests including bleeding and clotting time , liver function test , renal function test , thyroid function test , lipid profile , ultra sound examination of abdomen and pelvis , chest in case-2 , all the investigations were normal except for high blood pressure ( 130/90 mm hg ) and elevated serum urea and creatinine levels ( 50 and 2.5 mg / dl respectively ) . spontaneous onset , isolated nature , constant presence of blood in the blister fluid and rapid healing in the absence of an identifiable local cause or systemic disorder differentiates abh from mucous membrane pemphigoid , bullous pemphigoid , bullous lichen planus , epidermolysis bullosa , dermatitis herpetiformis , linear iga disease and oral amyloidosis . the classical history and morphology of lesions helped us to arrive at the clinical diagnosis of angina bullosa hemorrhagica in both the presenting cases . abh is a benign phenomenon that is characterized by the sudden appearance of a blood filled blister on the oral mucosa in the absence of an identifiable cause or systemic disorder , commonly seen in middle and elderly people with no sex predilection . bulla is typically seen on soft palate and occasionally on lateral border of tongue , gingiva and buccal mucosa . onset is rapid and blistering starts over few minutes which breaks down in minutes to hours to form shallow ulcer and heals spontaneously over 3 - 10 days . recurrences can be seen at the same or different oral site in 30% of people . local factors implicated are trauma from hot foods , dental procedures and endoscopy , local anaesthesia , and chronic steroid inhalation and systemic causes are hypertension , asthma , diabetes , rheumatoid arthritis , gastrointestinal disturbances and hyperuracemia . yamamoto et al . in his report of 11 cases , described a case of abh associated with renal failure . it has been known that abh presents with recurrences at regular intervals , usually associated with some internal disease or with some medications . in our cases reported here , case-1 had a classical presentation with pronged history of irregular presentation for 25 years without any other associated disease or drug intake . case 2 presented with a classical presentation of first episode associated with blood pressure and renal failure on dialysis . these cases are reported for the relative rarity of this entity and the diversity of presentation with reference to site within the oral cavity ( in case -1 , presenting at an atypical site ) and diverse aetiology . this report though does not convey significant new information it would certainly help to create more awareness among dermatologists and oral physicians to be able to differentiate from a host of other blistering disorders of varying aetiologies in the oral cavity . angina bullosa hemorrhagica may be seen in renal failure patients on dialysis and may have recurrence for long periods . this reprt helps to create awareness among dermatologists and oral physicians to be able to differentiate from a host of other blistering disorders of varying aetiologies in the oral cavity .