Faculty Bibliography

A delayed cutaneous response to cold, characterized by areas of erythematous, edematous deep swelling at 9 to 18 hr after experimental ice challenge, was recognized in a 10-yr-old boy and several members of his family. Biopsy of the cold-induced lesion showed edema and an infiltrate of mononuclear cells; mast cells were normal, and immunoglobulins, complement factors, and fibrin were not detected by immunofluorescence techniques. Local cold challenge did not release histamine or induce alterations in the complement system or the enzymes, histaminase, and histamine methyl transferase. The delayed cutaneous response to cold could not be passively transferred with serum or tissue extracts to monkey skin. Family studies suggested an autosomal-dominant mode of inheritance

Tear samples from 13 normal volunteers and nine patients with vernal conjunctivitis were assayed for histamine. Tears in both groups contained histamine. The normal subjects had values ranging from 2.2 to 36 ng/ml with a mean of 10.3 ng/ml. The vernal patients had histamine values ranging from 0 to 125 ng/ml with a mean of 3,.2 ng/ml. The presence of histamine in tears indicates a role for this important mediator in both the physiologic and immunologic processes of the external eye

A patient with cutaneous necrotizing vasculitis had chronic urticaria associated with multiple system involvement including arthralgias, glomerulonephritis, myositis, pseudotumor cerebri, and adenopathy. Persistent hypocomplementemia is noted with classic pathway activation. The syndrome recognized in this patient and those few individuals reported previously seems to constitute a distinct category of collagen-vascular disease

Cutaneous necrotizing angiitis may be present as either palpable purpura or less commonly as recurrent urticaria, and each clinical presentation may be associated with hypocomplementemia or a normal complement system. A variety of mechanisms may be operative in the production of necrotic vascular skin lesions that appear as similar, recognizable morphologic lesions. These mechanisms include immune complexes, cellular-type hypersensitivity reactions, and initiation or modulation by mast cells. Two cellular patterns have been recognized in the skin of patients with cutaneous necrotizing angiitis that can be correlated with the involvement of the complement system in serum. In patients with hypocomplementemia, there is an infiltrate of neutrophils that is consistent with a process involving immune complexes; in patients with normocomplementemia there are lymphocytes and activated lymphocytes consistent with participation in part by cellular mechanisms. In both the hypocomplementemic and normocomplementemic forms and as well as in a unique patient in whom the mast cell may initiate the venular damage, the mast cell, which its content of chemical mediators, has the capacity to initiate as well as modulate subacute and chronic vascular damage

The mast cell in tissues represents an effector cell capable of elaboration of all the essential mediators of inflammation. The effects of uncontrolled activation may be divided into pharmacologic and inflammatory phases with attendant implications for the initiation of both acute and subacute pathologic processes. The elaboration of chemical mediators by the mast cell makes it possible to recruit blood cells and proteins essential to host defense by a controlled physiologic process that can proceed without significant local tissue damage. When uncontrolled, the same potentiality can be injurious, with the nature of the clinical problem depending upon the location of the cells, the intensity of activation, and the ratio of newly generated and preformed mediators released. The evidence that the mast cell can participate in each form of immunologic reaction--immediate, immune complex, and delayed- as a primary or secondary effector cell and the diversity of its products foretell an evolving recognition of its role in host defense and tissue injury. It is pertinent to develop further methods and criteria to define the nature and extent of mast cell participation in disease processes

A group of patients has been identified with cutaneous necrotizing venulitis (vasculitis). These patients, some with concomitant connective tissue disorders, have skin lesions that separate them from the arteritis commonly described as rheumatoid vasculitis. HLA typing has been performed on 31 of these unrelated patients with cutaneous necrotizing venulitis, including 19 with associated chronic disorders. The antigen pair A11, BW35 was found in 5 of these 19 patients and in 11 of 346 controls. This difference in frequency is statistically significant. Because HLA genes appear to be linked to immune response genes, these data suggest that such genes may exist in patients with this form of cutaneous necrotizing venulitis with associated connective tissue disease

Two distinct cellular patterns of necrotizing angiitis involving venules in skin of patients with clinically identical cutaneous lesions were appreciated by the 1 -mum-thick section technique. In those individuals with serum hypocomplementemia, there was a perivenular inflitrate composed predominantly of neutrophils with fibrin deposition and nuclear debris. In patients with normal serum complement levels, in addition to an infiltrate of neutrophils and fibrin deposition, perivenular lymphocytes in various stages of activation were prominent. In both patterns the venules and not the arterioles were affected, mast cells exhibited various degrees of hypogranulation, and basophils and eosinophils were recognized only rarely. Lesions of different clinical age obtained from one hypocomplelmentemic patient and one normocomplementemic patient exhibited consistent cellular patterns, as did a single crop of lesions biopsied twice, 24 hr apart, in a patient with hypocomplementemia. No patient with hypocomplementemia became normocomplementemic or vice versa with persistence of lesions

Patients with idiopathic acquired cold-induced urticaria were evaluated for the release of the preformed mast-cell mediators of immediate-type hypersensitivity during a study in which one arm was immersed in ice water while the other arm remained as a control. Blood specimens were obtained from each arm serially over a one-hour interval, and serum speciments were assessed for histamine, eosinophil chemotactic factor of anaphylaxis, and complement components. Levels of histamine and eosinophil chemotactic factor rose in the arm subjected to cold immersion for three minutes, with peak values occurring between two and five minutes and returning to base line by 30 minutes. No changes occurred in the control arm or in the immersed arm of normal subjects. Assessment of the classical and alternative complement pathways showed no abnormalities. This initial observation of release of eosinophil chemotactic factor of anaphylaxis in vivo along with histamine assigns the mast cell a central role in cold urticaria