Urticaria Pigmentosa

Localized form of mastocytosis. Degranulation must be avoided during all anesthetic procedures (physiological and psychological stress, drugs).

Urticaria Perstans Hemorrhagica with Pigmentosa; Localized Infantile Mastocytosis; Nettleship E Disease type I; Xanthelasmoidea.

Although rare, it is most often seen in children, however it can also occur in adults. Affects males and females equally.

Both autosomal and recessive inheritance have been evocated, however sporadic cases have also been reported.

Unknown. When mast cells proliferate, histamine and heparin are released into the skin. Mastocytosis presents with characteristic skin lesions of urticaria and telangiectasis.

Urticaria pigmentosa is a localized form of mastocytosis. It is generally benign and is usually self-limited. Diagnosis is clinically evocated in a child older than age 2 years with skin lesions affecting the neck, arms, legs, and trunk. The rash consists of reddish-brown spots that turn into hives when they are rubbed hard or scratched. Certitude diagnosis can be obtained with skin biopsy.

Skin lesions can also include bullous mastocytosis and telangiectasia macularis eruptiva perstans (multiple hyperpigmented telangiectatic macules, located primarily on the trunk and on the extremities). In the early form, resolution of the condition by adolescence or early adulthood is common. In the form beginning after 5 years of age, the abnormal collections of mast cells sometimes involves other organs. It can affect bone, gastrointestinal tract, lymphatics, spleen, and liver, resulting in clinical signs such as abdominal pain or gastric ulcer. It is even possible to observe an overgrowth of mast cells progressing to a malignant out-of-control process called mast cell leukemia. Mast cells can abruptly release vasoactive mediators, such as histamine, heparin, and prostaglandins, under some physical stresses or in response to drugs. Severe general reaction with shock can occur.

Obtain full medical and physical history. One must review the signs and symptoms of previous cardiovascular instability, i.e., hypotension, loss of consciousness, vomiting, and severe flushing and sweating. Evaluate organ involvement (clinical, ultrasound).

Both regional and general anesthesia can produce life-threatening complications. Avoid mastocyte degranulation (e.g., mild temperature in the operating room), psychological and physical stress. Resuscitation drugs should be present in the operating room. Careful with the insertion of nasal tubes (easy bruising and nose bleeds).

Many drugs have been associated with mast cell degranulation (lidocaine, morphine, oxymorphone, codeine, d-tubocurarine, metocurine, acetylsalicylic acid, etomidate, thiopental, succinylcholine, enflurane, isoflurane methylparaben and para-aminobenzoic acid). Consider use of intradermal skin tests to predict which medications may cause problems and those that may be used. Regional anesthesia should be preferred when possible because it restricts the use of several different drugs. (One should prefer amide-type over ester-linked local anesthetics.) Consider preoperative administration of H1 and H2 blockers and steroids. Preoperative sedation can be useful (e.g., hydroxyzine) to reduce patient stress. Avoid atropine. Muscle relaxants are not contraindicated but it is recommended to choose those with minimal histamine-liberation. These medications should be administered slowly to prevent a sudden and massive histamine release. Preinduction dose of 25 to 50 mg diphenhydramine intravenously has been suggested to reduce the risk of mastocyte degranulation. Epinephrine should be available at all times to treat general and acute signs of degranulation.

Other mastocytoses provide more general reaction than urticaria pigmentosa.