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Human parvovirus infection: rheumatic manifestations, angioedema, C1 esterase inhibitor deficiency, ANA positivity, and possible onset of systemic lupus erythematosus.

OBJECTIVE: To investigate the clinical and serological characteristics of parvovirus infection. METHODS CASE SERIES: during 1993-4, 9 adult patients presented with polyarthralgias/polyarthritis. Clinical evaluation and serological studies of antinuclear antibodies, rheumatoid factor (RF), IgM and IgG antibodies to human parvovirus were done in all patients. Other serologies including anti-DNA, serum complement, and C1 esterase inhibitor levels were obtained in some patients. RESULTS: All 9 patients had polyarthralgias/polyarthritis, serological evidence of parvovirus B19 IgM and IgG antibodies, and normal sedimentation rate. All patients were seronegative for RF. Four women had positive ANA titers. In 2 of them the ANA positivity was transient. One developed systemic lupus erythematosus (SLE). Three women had angioedema of the face and tongue; one had transient C1 esterase inhibitor deficiency and another a transient decrease in C4 levels. CONCLUSION: Parvovirus may be implicated in the development of SLE as well as other chronic arthropathies. This is the first reported case of angioedema and decreased C1 esterase inhibitor levels associated with parvovirus infection.

Adult↗

Fibrinolytic abnormalities following liver transplantation in patients with fulminant hepatic failure.

OBJECTIVE: To evaluate the fibrinolytic system after liver transplantation in patients with fulminant hepatic failure. DESIGN: Seven patients were studied prior to, and for 4 days after, liver transplantation. METHODS: Both activators and inhibitors of the fibrinolytic system were investigated in seven patients with fulminant hepatic failure who underwent liver transplantation. RESULTS: alpha 2-antiplasmin and C1-inhibitor levels increased rapidly after transplantation (81 and 53% of normal on day 1; 106 and 99% on day 2, respectively). Plasminogen levels remained low throughout the 4-day study period. Plasminogen activator inhibitor-1 was higher than normal before transplantation (21.0 compared with 7.4 U/ml) and increased further on the first day after operation (37.5 U/ml; P < 0.05 versus pre-transplantation). Tissue plasminogen activator levels remained normal (pre-operative, 7.0 IU/ml; Day 4, 0.2 IU/ml). D-dimer remained elevated during the postoperative period showing increased fibrinolytic activity. Thrombin-antithrombin III complex was also elevated during the study period. Antithrombin III was greatly reduced prior to transplantation (13.7% of normal) and plasma levels were less than 50% of normal values during the study. CONCLUSIONS: Measures of fibrinolytic activity are raised after liver transplantation in patients with fulminant hepatic failure. This is probably due to increased fibrin formation caused by a coexisting hypercoagulable state.

Adult↗

Recurrent febrile panniculitis and hepatitis in two patients with acquired complement deficiency and paraproteinemia.

Repeated episodes of febrile panniculitis and hepatitis were the main clinical features in two patients with an IgG1 kappa paraproteinemia and severe depletion of the early components of the classical pathway of complement (acquired C1 inhibitor deficiency). They did not have episodes of cutaneous angioedema or evidence of immune complex disease. In the more severely affected patient, the episodes responded to steroids. These features have not been described with acquired C1 inhibitor deficiency and may be related to complement activation.

Complement Activation↗

[Hereditary or acquired angioedema caused by functional deficiency of C1 inhibitor--a still unfamiliar disease picture].

Hereditary angioneurotic oedema or hereditary angiooedema (HAE) and acquired angiooedema (AAE) are disorders of the C1-inhibitor (C1-INH) protein, caused by the lack, dysfunction or exhaustion of the C1-INH molecule. Inadequate function of C1-INH results in inappropriate control of various enzymes of the fibrinolytic, complement and kinin systems as well as of factor XII, being the initial enzyme of the kinin and contact coagulation systems. As C1-INH functional deficiency is rare and the clinical manifestation little known, even nowadays the most feared complication of the deficiency may evolve: death from acute airway obstruction. Patients deficient in C1-INH function whose clinical manifestations are misinterpreted as allergic angiooedema are most at risk for fatal laryngeal oedema. The therapy of allergic and C1-INH-related angiooedema is fundamentally different. The background for the hereditary form of inadequate C1-INH function is a gene defect. The predominant primary underlying disease of the acquired form of the deficiency (AAE) is a lymphoproliferative process.

Angioedema↗

[Immunopathology in 35 cases of chronic urticaria].

Although urticaria is usually held to be a type 1 hypersensitivity reaction, it may also be the cutaneous manifestation of vasculitis mediated by immune complexes. In this study of 35 patients with chronic urticaria, the authors attempted to specify the prevalence of vasculitis and its possible correlations with particular clinical and/or immunological findings. In 10 cases, lymphocyte subpopulations were also studied, using monoclonal antibodies. Patients included 21 women and 14 men, aged 19 to 80. In each patient: a) systemic signs were looked for by history taking and physical examination; b) a skin biopsy was examined by optic microscopy and direct immunofluorescence; c) the following biological investigations were done: blood count, sedimentation rate, protein electrophoresis and immunoelectrophoresis, IgE, B virus markers, circulating immune complexes, anti-nuclei and anti-ADN antibodies, latex and Waaler-Rose tests, total complement, C3, C4, and C1 esterase inhibitor. Visceral involvement and various immunological disorders are most common in those patients with leukoclastic (n = 7) or mononuclear (n = 9) vasculitis. These patients, as well as those recently studied in the literature, have idiopathic chronic urticaria, the least severe of urticarial vasculitis.

Adult↗

The effect of cleavage by a Crotalus atrox alpha-proteinase fraction on the properties of C1-inhibitor.

The effect of cleavage of C1-inhibitor at Pro36 by a Crotalus atrox alpha-proteinase fraction on the properties of this serpin was studied. This truncated C1-inhibitor (des 1-36) was fully active as an inhibitor of kallikrein, beta-factor XIIa, and C1s, and modulated the functions of C1 in a normal manner. Also, the half-life of the truncated protein in the circulation of rabbits, both alone and in complex with C1, was not altered. These results show that shock-like symptoms caused by C. atrox envenomation are not attributable to a deficiency in C1-inhibitor caused by the action of the metalloproteinase in the alpha-proteinase fraction.

Amino Acid Sequence↗

Biosynthesis in vitro of complement subcomponents C1q, C1s and C1 inhibitor by resting and stimulated human monocytes.

The capacity of cultured human monocytes to synthesize and to secrete the subcomponents of C1 and C1 inhibitor was examined. Non-stimulated monocytes secreted C1q and C1s from day 5 of culture. C1s reached a plateau immediately at its maximum level, whereas C1q secretion increased progressively until the end of the second week. Between day 12 and day 25, C1q secretion remained nearly constant (1-15 fmol/day per microgram of DNA, depending on the donor), whereas C1s secretion decreased and even in some cases stopped. C1r and C1 inhibitor were not secreted in detectable amounts by these resting cells. Stimulation of monocytes by yeasts, immunoglobulin G-opsonized sheep red blood cells or latex beads did not modify consistently C1q and C1s secretion. Activation by conditioned media from mitogen-, antigen- or allogeneic-stimulated lymphocyte cultures increased C1q production from 2 to 7 times and re-activated C1s secretion. Under the same conditions of activation, C1 inhibitor was secreted (up to 300 fmol/day per microgram of DNA) and C1r became detectable in culture supernatants. Isolated human monocytes are thus able to synthesize the whole C1 subcomponents; C1, if assembled, could be protected from non-immunological activation by locally produced C1 inhibitor. Activated monocytes appear to be a good tool for studying the assembly of C1 subcomponents and the role of C1 inhibitor in this process.

Cells, Cultured↗

Hereditary angioedema with normal C1-inhibitor activity in women.

BACKGROUND: Hereditary angioedema (HAE) is a well defined autosomal dominant disease (Mendelian Inheritance in Man #106100) that results from an inherited deficiency of C1 (the activated first component of complement) inhibitor function. We report an unusual variant of HAE with normal biochemical C1-inhibitor function, occurring only in women. METHODS: We screened 574 patients with recurrent angioedema of the skin for presence of HAE. 283 patients were selected, in whom angioedema was associated with abdominal pain attacks or recurrent life-threatening episodes of upper-airway obstruction, or both, rather than with urticaria. We measured C1-inhibitor concentration and functional activity as well as complement C4 concentration and took pedigrees to characterise patients. FINDINGS: 94 HAE cases with C1-inhibitor deficiency, positive family history, or both were identified. Biochemical testing showed that 84 patients from 49 families had a functional C1-inhibitor deficiency. 11 of these patients had no affected family members (probably representing de-novo mutations). Ten women with HAE, from ten families, had normal C1-inhibitor protein concentrations and function, and normal C4 concentration. A more detailed study of these families identified another 26 affected members, who were also all women. Of those women, 14 could be studied and also had normal C1-inhibitor concentration and function. The disease was seen in successive generations, and in offspring of affected mothers, the sex ratio (M/F) was shifted to 1/1.5. INTERPRETATION: HAE with normal C1-inhibitor concentration and function represents a unique genetic disease arising only in women. The formal genetics of this entity are suggestive of an X-linked dominant mode of inheritance. For this disorder we propose the term hereditary angioedema type 3 (HAE III).

Abdominal Pain↗

Angioedema without urticaria: a large clinical survey.

BACKGROUND: Angioedema without major urticarial flares (hives) is poorly understood. Its causes are diverse, and little is known about its pathogenic mechanisms. We report on our 11 years of experience with this condition and propose a classification of patients affected by angioedema unaccompanied by urticaria. METHODS: From 1993 through 2003 at our outpatient clinic, 929 consecutive patients were examined for recurrent angioedema unaccompanied by urticaria. A detailed history was taken to identify known causes of angioedema, with special attention to external allergenic agents. Each patient underwent a complete physical examination, routine laboratory tests (blood cell count, protein electrophoresis, erythrosedimentation rate, examination of stool for ova and parasites, pharyngeal and urine cultures, sinus and dental radiography, and measurements of antitissue autoantibodies and rheumatoid factor in plasma), and complement parameters (C1 inhibitor, C4 and C1q). Further testing was done when pertinent, based on clinical findings. When all results were negative, response to H1-antihistamine was considered. RESULTS: Angioedema could not be classified in 153 patients who were lost to follow-up (16.4%). Among the 776 cases with adequate data, these types of angioedema were identified: 124 (16%) related to external agents such as a drug, insect bite or foodstuff; 85 (11%) related to treatment with angiotensin-converting enzyme inhibitor; 55 (7%) associated with an autoimmune disease or infection; and 197 (25%) caused by C1 inhibitor deficiency. In the other 315 cases (41%), the etiology was undiscovered: 254 cases (33% of the study sample) were idiopathic histaminergic; 40 (5%) were idiopathic nonhistaminergic; and 21 (3%) had other causes of peripheral or generalyzed edema. INTERPRETATION: Our data indicated that angioedema without urticaria could be classified according to specific clinical and pathogenic characteristics, and we have suggested a work-up for patients experiencing this condition.

Adolescent↗