Mastocytosis (urticaria pigmentosa)

Acute and chronic urticaria have a wide variety of allergic etiologies. Less common systemic causes of urticaria are mastocytosis (urticaria pigmentosa), hyperthyroidism, malignancy, and juvenile rheumatoid arthritis.

Systemic mastocytosis, which may be associated with the skin lesion urticaria pigmentosa, may cause diarrhea that is either secretory and mediated by histamine, or inflammatory and due to intestinal filtration by mast cells.

Patients with an unusual form of mastocytosis (telangiectasia macularis eruptiva perstans), the carcinoid syndrome, and ataxia-telangiectasia also have linear telangiectasias.

The term atopic allergy implies a familial tendency to manifest such conditions as asthma, rhinitis, urticaria, and eczematous dermatitis (atopic dermatitis) alone or in combination. However, individuals without an atopic background may also develop hypersensitivity reactions, particularly urticaria and anaphylaxis, associated with the same class of antibody, IgE, found in atopic individuals. Inasmuch as the mast cell is the key effector cell of the biologic response in allergic rhinitis, urticaria, anaphylaxis, and systemic mastocytosis, the introduction to these clinical problems will consider the developmental biology, activation pathway, product profile, and target tissues for this cell type.

Types of Urticaria

1. Solar urticaria characteristically occur within minutes of sun exposure and are a skin sign of one systemic disease¾erythropoietic protoporphyria.
2. Cold urticaria are precipitated by exposure to the cold, and therefore exposed areas are usually affected.
3. Cholinergic urticaria are precipitated by heat, exercise, or emotion and are characterized by small wheals with relatively large flares.

Treatment of Mastocytosis (urticaria pigmentosa)

Cromolyn administered orally is indicated in the treatment of mastocytosis. It has been shown to improve the symptoms of mastocytosis, such as diarrhea, flushing, headache, vomiting, urticaria, abdominal pain, nausea, and itching.

Omeprazole is also indicated for the treatment of mastocytosis.

Amyloidosis
Connective tissue naevi
Dermatofibroma
Dermatofibrosarcoma protuberans
Ehler's Danlos syndrome
Elastosis perforans serpiginosa
Keloids & hypertrophic scars
Lipodystrophy
Lipoma
Mastocytoma
Neurofibroma
Pseudoxanthoma elasticum
Reactive perforating collagenosis
Striae (stretch marks)
Eosinophilic fasciitis
Erythema multiforme
Histiocytoses
Jessner's lymphocytic infiltrate
Langerhans cell histiocytosis
Lymphocytoma cutis
Lymphomatoid papulosis
Mastocytosis
Morphoea
Non-Langerhans cell histiocytosis
Panniculitis
Reticulohistiocytosis
Sweet's disease
Systemic sclerosis
Atypical mycobacterial infection
Granuloma faciale
Granuloma annulare
Cutaneous tuberculosis
Leprosy
Pyogenic granuloma
Sarcoidosis