What is haematohidrosis?
Haematohidrosis is the spontaneous sweating of blood from intact skin or mucosa.
Haemolacria (blood-stained tears), otoerythrosis (spontaneous bleeding from the ear), and other sites including nose (epistaxis), urina (haematuria), vagina, and bowel may be associated.
Who gets haematohidrosis?
Haematohidrosis is reported rarely. There is a marked female predominance (>80%) with the majority of described cases aged 9-15 years (age range 6 months-72 years). Nearly two-thirds of reported cases have been Asian, particularly from India and Pakistan. Africa is the next most common continent reporting cases. Few case reports have emerged from Europe or the Americas. This may reflect a genetic predisposition in darker skin types, further supported by the report of affected siblings.
What causes haematohidrosis?
The cause of haematohidrosis is unknown. It has been associated with periods of stress or anxiety. During severe stress or extreme anxiety, vascular capillaries constrict and then dilate. It is postulated that during the dilation phase capillaries around sweat glands and hair follicles may rupture forcing blood into sweat glands and/or hair follicles resulting in blood staining of fluid reaching the skin surface. However in many cases no triggering factors have been identified.
Blood tests do not demonstrate a clotting disorder and skin biopsies are normal.
What are the clinical features of haematohidrosis?
Haematohidrosis is the spontaneous sweating of blood-stained fluid from intact skin. It can occur at any time, including during sleep, and may occur multiple times per day. There may be prodromal symptoms of soreness or tingling at the site, or general symptoms such as headache, abdominal pain, nausea, or vomiting. The face, especially the forehead, is the commonest site reported; it can occur at several different sites on the body simultaneously or at different times. Bleeding from mucosal surfaces such as the mouth has also been described. The amount of bleeding is typically small, lasts minutes, and stops spontaneously. The blood-stained fluid is described as pink and watery, clearer than blood. After wiping the blood-stained fluid from the skin, the underlying skin is intact with no sign of trauma.
What is the differential diagnosis of haematohidrosis?
- Dermatitis artefacta
- Platelet and coagulation abnormalities
- Cutaneous vascular anomalies or fragility.
How is haematohidrosis diagnosed?
Haematohidrosis is a diagnosis of exclusion.
Diagnostic criteria have been suggested:
- recurrent episodes of spontaneous, painless, and self-limited oozing of a blood-stained fluid observed by health professionals
- usual blood components are found on examination of the fluid
- site of bleeding is intact with no abrasion, telangiectasia, or purpura
- no oozing after wiping the area.
Investigations may include:
- Skin biopsy immediately following a bleeding episode is usually normal
- Microscopy of the fluid demonstrates the presence of normal blood constituents. Biochemical analysis shows the haemoglobin concentration is lower than in venous blood.
- Full blood count, coagulation tests, and a vasculitis screen
- A psychiatry referral to explore a possible psychogenic cause or trigger.
What is the treatment and prognosis of haematohidrosis?
Reported treatments include:
- Beta-blockers (oral propranolol 10-20mg/d)
Haematohidrosis is benign and transient, usually resolving spontaneously.