Search

We developed a questionnaire to examine the findings of cutaneous arteritis among dermatological specialists experienced in vasculitis as certified by the Committee for guidelines for the management of vasculitis and vascular disorders of the Japanese Dermatological Association. We sent a questionnaire to 12 dermatological facilities identified through the revised Committee for guidelines for the management of vasculitis and vascular disorders of the Japanese Dermatological Association. Retrospective data obtained from 84 patients at the 12 dermatological facilities between 2012 January 2016 December were evaluated. The 84 patients were categorized into two groups, a systemic steroid treatment group (group 1, n = 52) and a no systemic steroid treatment group (group 2, n = 32). C-reactive protein in group 1 patients was significantly higher than that in group 2 patients. Frequency of fever, arthritis, myalgia- and peripheral neuropathy in group 1 was significantly higher than that in group 2. We propose that these symptoms could serve as early markers for the transfer from cutaneous arteritis to systemic polyarteritis nodosa. We further suggest that patients who are subsequently associated with cerebral hemorrhage and infarction, who are originally diagnosed as having cutaneous arteritis, could progress to systemic polyarteritis nodosa. The study demonstrated that it is important for dermatologists to detect these findings early in order to establish an accurate diagnosis and a timely treatment., (© 2020 Japanese Dermatological Association.)

We measured both serum anti-phosphatidylserine-prothrombin complex (anti-PSPT) antibodies and anti-moesin antibodies, as well as various cytokines (interleukin [IL]-2, IL-4, IL-5, IL-10, IL-13, IL-17, granulocyte macrophage colony-stimulating factor, γ-interferon, tumor necrosis factor-α) levels in polyarteritis nodosa (PAN) patients with cutaneous manifestations. All patients showed the presence of a histological necrotizing vasculitis in the skin specimen. They were treated with i.v. cyclophosphamide pulse therapy (IV-CY) and prednisolone therapy or steroid pulse therapy. The immunological assessments were performed on sera collected prior to and after treatment with IV-CY or steroid pulse therapy. We found a significant positive correlation between serum anti-moesin antibodies and both clinical Birmingham Vasculitis Activity Scores and Vasculitis Damage Index. Anti-PSPT antibody and IL-2 levels after treatment in PAN patients were significantly lower than before treatment. In contrast, anti-moesin antibody levels were higher following IV-CY or steroid pulse therapy compared with the pretreatment levels. In the treatment-resistant PAN patients (n = 8), anti-PSPT antibody levels after treatment were significantly lower than before treatment. In contrast, anti-moesin antibody levels after treatment in the patients were significantly higher compared with the pretreatment levels. Immunohistochemical staining revealed moesin overexpression in mainly fibrinoid necrosis of the affected arteries in the PAN patients. We suggest that measurement of serum anti-PSPT antibody levels could serve as a marker for PAN and aid in earlier diagnosis of PAN. We also propose that elevated serum anti-moesin antibodies could play some role of the exacerbation in patients with PAN., (© 2016 Japanese Dermatological Association.)

Polyarteritis nodosa is a necrotizing vasculitis of medium-sized arteries of unknown origin. Hypertension is present in 30% of patients with polyarteritis nodosa. In those cases, high renin levels are thought to be secondary to renal involvement. The present study was performed to identify causal factors of polyarteritis nodosa. In cyp1a1ren-2 transgenic rats, vasculitis of medium-sized arteries resembling classical polyarteritis nodosa can be induced. In this model, oral administration of indole-3-carbinol (I3C) activates the liver-specific cyp1a1 promoter, leading to prorenin expression in a dose-dependent manner. After the first 6 weeks of chronic induction with 0.125% I3C, the mean arterial pressure reached a plateau of about 170 mmHg. Ten out of 11 I3C-treated rats, which were chronically instrumented with a telemetric device to measure blood pressure, developed polyarteritis nodosa within 10 weeks of I3C treatment. I3C alone or instrumentation alone did not cause polyarteritis nodosa. The angiotensin-converting enzyme inhibitor captopril completely prevented the development of polyarteritis nodosa, indicating that local angiotensin II generation is a pathogenetic factor in this model. The renin-angiotensin system can play a primary role in the development of polyarteritis nodosa in rats.

Objective: Previous studies of polyarteritis nodosa (PAN) included patients with microscopic polyangiitis, because these entities were not distinguished prior to the Chapel Hill Consensus Conference (CHCC). This study was undertaken to describe the main characteristics of and long-term outcomes in patients with well-characterized PAN diagnoses., Methods: We conducted a systematic retrospective study of 348 patients who were diagnosed as having PAN between March 1963 and October 2005, were registered in the French Vasculitis Study Group database, and satisfied the American College of Rheumatology and CHCC criteria. Patient characteristics and outcomes were analyzed and compared according to hepatitis B virus (HBV) status., Results: At diagnosis, the mean +/- SD age was 51.2 +/- 17.3 years. The most frequent findings were general symptoms (93.1%), neurologic manifestations (79%), skin involvement (49.7%), abdominal pain (35.6%), and hypertension (34.8%); 66.2% had renal artery microaneurysms; 70.1% had histologically proven PAN. Patients with HBV-related PAN (n = 123) had more frequent peripheral neuropathy, abdominal pain, cardiomyopathy, orchitis, and hypertension compared with patients with non-HBV-related PAN (n = 225). During a mean +/- SD followup of 68.3 +/- 63.5 months, 76 patients (21.8%) relapsed (63 with non-HBV-related PAN [28%] versus 13 with HBV-related PAN [10.6%]; P < 0.001); 86 patients (24.7%) died (44 with non-HBV-related PAN [19.6%] versus 42 with HBV-related PAN [34.1%]; P = 0.003). Five-year relapse-free survival rates were 59.4% (95% confidence interval [95% CI] 52.6-67.0) versus 67.0% (95% CI 58.5-76.8) for non-HBV-related PAN and HBV-related PAN, respectively. Multivariate analysis retained age >65 years, hypertension, and gastrointestinal manifestations requiring surgery or at least consultation with a surgeon as independent predictors of death, whereas patients with cutaneous manifestations or non-HBV-related PAN had a higher risk of relapse., Conclusion: Our findings indicate that the rate of mortality from PAN remains high, especially for the elderly, and relapses do occur, particularly in patients with non-HBV-related PAN with cutaneous manifestations.

Sixteen cases of cutaneous polyarteritis nodosa referred to our Department from 1985 to 2003 were studied clinically and histopathologically. Laboratory data, treatments and clinical courses were also evaluated retrospectively. All cases had nodules and/or indurated erythemas on their lower extremities. All cases showed necrotizing vasculitis of small muscular arteries in the subcutaneous tissues and/or occlusion of those arteries histopathologically. Fifteen cases also had accumulation of plasma protein in vessels of the dermis and subcutaneous tissues. Laboratory data showed high activity of platelets and coagulation in some cases. Eleven cases had been effectively treated with non-steroidal anti-inflammatory drugs. Eight cases were observed for at least 5 years (the longest for approximately 19 years) and had good prognoses and no systemic involvement. Cutaneous polyarteritis nodosa seems to be a benign disease, and differs from systemic polyarteritis nodosa although their histopathological features are common. Cutaneous polyarteritis nodosa might involve local dysfunction of the circulation from the dermis to the subcutaneous area. A review of the published work shows that the cause(s) of most cases of cutaneous polyarteritis nodosa is unknown, that no controlled trials for treatment of cutaneous polyarteritis nodosa compared to polyarteritis nodosa have been reported, and that no definitively effective therapy for cutaneous polyarteritis nodosa has been established.

Objective: Myocardium and coronary arteries can occasionally be affected in patients with systemic necrotizing vasculitides; however, such involvement has not been systematically assessed using cardiovascular magnetic resonance imaging (MRI)., Methods: Magnetic resonance angiography and contrast-enhanced MRI were applied for the assessment of coronary arteries (the left anterior descending [LAD], left circumflex [LCx], and right coronary artery [RCA]) and myocardium, respectively, in 39 patients with vasculitis who were asymptomatic for cardiac disease (16 with microscopic polyangiitis [MPA], 11 with Wegener's granulomatosis [WG], 9 with Churg-Strauss syndrome [CSS], and 3 with polyarteritis nodosa [PAN]). Data were compared with age-matched disease-control patients with rheumatoid arthritis (n = 20) or systemic lupus erythematosus (n = 13), and with healthy control individuals with normal coronaries (n = 40)., Results: Patients with MPA, WG, and PAN (but not with CSS) were found to display significantly increased maximal diameters of coronary arteries compared with healthy controls (for MPA and WG; P < 0.001 for LAD and RCA, and P < 0.01 for LCx) and with both disease-control groups (for only MPA; P < 0.01 for LAD and RCA, and P < 0.05 for LCx). Fusiform coronary aneurysms were detected in patients with MPA (4/16) and PAN (2/3), whereas coronary ectasias were evident in patients with MPA (14/16) and WG (2/11). The presence of myocardial necrosis (by assessment of late gadolinium-enhanced images) was identified only in patients with MPA (2/16) and CSS (3/8 studied)., Conclusion: Cardiovascular MRI assessment of patients with systemic vasculitis revealed coronary ectatic disease in the majority of patients with MPA and PAN, as well as in several patients with WG. Myocardial necrosis can be detected in MPA and CSS.

Objective: Mixed cryoglobulinemia (MC) is a systemic vasculitis, usually associated with hepatitis C virus (HCV) infection. The molecular mechanisms responsible for HCV-associated MC (HCV-MC) vasculitis are largely unknown. This study was undertaken to assess the expression profile of selected genes involved in inflammatory vascular damage in patients with HCV-MC vasculitis, patients with polyarteritis nodosa (PAN), and patients with noninflammatory idiopathic neuropathy., Methods: The quantitative expression levels of 42 selected genes involved in inflammatory vascular damage were assessed in nerve lesions of patients with HCV-MC vasculitis, PAN (rheumatic disease controls), and noninflammatory idiopathic neuropathy (noninflammatory neuropathy controls), using real-time reverse transcriptase-polymerase chain reaction. Genes were considered to be differentially expressed when there was a >2-fold difference in mean expression levels between groups and the P value was less than 0.05., Results: Expression levels of 8 genes were significantly increased in HCV-MC patients versus control patients with noninflammatory idiopathic neuropathy, with the highest increase for metallothionein 1 H (MT1H), a hypoxic and oxidative stress protein. Compared with PAN patients, HCV-MC patients had higher expression levels of genes encoding oxidative stress-derived molecules (MT1H, endothelial cell nitric oxide synthase 3, Hsp70, and Hsp90) and tissue plasminogen activator and lower expression levels of matrix metalloproteinase 7 (MMP-7). HCV-MC neuropathies were classified according to their morphologic pattern and the presence or absence of necrotizing arteritis. MMP-1, MMP-7, MMP-9, and interleukin-1beta were up-regulated in patients with necrotizing arteritis., Conclusion: This comprehensive molecular study of HCV-MC vasculitis provides strong evidence that MMPs, proinflammatory cytokines, and oxidative stress-derived molecules have a role in the pathogenesis of HCV-MC vasculitis neuropathy.

Unlabelled: Polyarteritis nodosa is a rare disease in childhood and adolescence that is difficult to diagnose clinically. We report on a 17-y-old girl presenting with a history of recurrent infections of the upper respiratory tract and conjunctivitis followed by a painful rash on the upper and lower extremities resembling erythema nodosum. The diagnosis of polyarteritis nodosa was proven by skin biopsy. Therapy with intravenous immunoglobulins failed, but with systemic steroids she responded promptly., Conclusion: Polyarteritis nodosa is a differential diagnosis in adolescents presenting with fever and an erythema nodosum-like rash.

Unlabelled: We report an unusual presentation of polyarteritis nodosa in a 2-y-old child. The child presented with a mass of the left leg adjacent to the calf, and the biopsy showed polyarteritis nodosa. Further investigations confirmed systemic features, and X-rays showed a periosteal reaction., Conclusion: Childhood polyarteritis nodosa may present with a lower limb inflammatory mass.

Objective: To describe initial clinical symptoms attributable to microscopic polyangiitis (MPA) or polyarteritis nodosa (PAN)., Methods: We retrospectively reviewed the medical files of 72 patients (mean followup 6.7 years) with biopsy-proven MPA (n = 36) or PAN (n = 36)., Results: Initial manifestations were similar in both entities except for peripheral neuropathy (P = 0.02) and gastrointestinal tract involvement (P = 0.006), which were significantly more frequent in PAN, and general signs alone in MPA (8%; P = 0.02). The mean time to diagnosis was 9.8 +/- 19.4 months; 35% of the patients died and 26% relapsed; significantly more MPA than PAN patients relapsed (P = 0.03). Time to diagnosis >/=90 days was associated with a trend toward more patients relapsing (P = 0.12), but not with an increased risk of mortality., Conclusion: Initial symptoms of MPA and PAN are usually nonspecific and last for several months before the diagnosis is made. A longer time to diagnosis is associated with a tendency to a higher relapse rate.

Cutaneous polyarteritis nodosa (PN) has a benign and chronic course; relapses are frequently associated with steroid dependence. We have observed four cases of cutaneous PN in the past 15 years and followed up two of the four cases long-term for 13 and 10 years after diagnosis. There has been a marked contrast in the clinical courses of these two cases: one case has shown a complete remission for 12.5 years without treatment during the most recent 11 years; the other case had four relapses and has never experienced cessation of treatment. The only difference between the two cases was careful therapy with adequate prednisolone in the long-term remission case. The other two cases clinically showed erythema nodosum-like features, and they had antecedent sore throats and embedded chronic tonsillitis; one was associated with presumed streptococcal infection. These two cases may simply be an accelerated process of post-streptococcal erythema nodosum rather than typical cutaneous PN. We performed tonsillectomies as adjuvant therapy in these two cases. No relapse of the disease has been observed in these two cases, and the tonsillectomy allowed us to taper the dose of steroids, resulting in discontinuation of the treatment in one of the two cases. The duration of the remission as well as the adjuvant therapy was variable in each of our cutaneous PN cases. Tonsillectomy can be recommended as an adjuvant to steroids for PN cases with chronic tonsillitis and/or streptococcal infection.

We describe three cases of polyarteritis nodosa cutanea (PNC) showing necrotizing arteritis and only cutaneous lesions without systemic symptoms or visceral involvement for eleven, six, and three years after the onset of the disease. Since it was first described, there has been continuous controversy as to whether PNC progresses to systemic PN. Some cases have been described which had begun with a cutaneous lesion and progressed to the systemic form 19 and 18 years after the onset of the disease, so we believe that long term follow-up of this disease is essential.

Segmental mediolytic arteriopathy, a rare, noninflammatory arterial disease, is fundamentally a variant of fibromuscular dysplasia. The characteristic angiographic findings of segmental mediolytic arteriopathy include the "string of beads" and microaneurysms which are indistinguishable from those of vasculitis, and the correct diagnosis can be made only after histopathologic evaluation of the arterial lesions. Thrombosis, arterial wall hemorrhage, and dissection are among the complications of segmental mediolytic arteriopathy. We describe herein a patient with segmental mediolytic arteriopathy who presented with hemoperitoneum. The patient underwent urgent surgical repair of a ruptured hepatic artery aneurysm. The postoperative visceral arteriography findings led to a clinical diagnosis of polyarteritis nodosa, and immunosuppressive therapy was initiated. This treatment was stopped as soon as the correct biopsy diagnosis of segmental mediolytic arteriopathy was obtained through outside consultation. The patient recovered without drug treatment and was spared the potentially life-threatening complications of immunosuppression.

Objective: To investigate endothelial cell adhesion molecule expression in vessels from patients with classic polyarteritis nodosa (PAN)., Methods: Frozen sections of 21 muscle and 16 nerve samples from 30 patients with biopsy-proven PAN and 12 histologically normal muscle and 2 histologically normal nerve samples from 12 controls were studied immunohistochemically, using specific monoclonal antibodies (MAb) that recognize adhesion molecules. Adhesion molecules identified were intercellular adhesion molecule 1 (ICAM-1), ICAM-2, ICAM-3, vascular cell adhesion molecule 1 (VCAM-1), platelet endothelial cell adhesion molecule 1 (PECAM-1), E-selectin, P-selectin, L-selectin, lymphocyte function-associated antigen 1 (LFA-1), and very late activation antigen 4 (VLA-4). Neutrophils were identified with a MAb recognizing neutrophil elastase. Endothelial cells were identified with the lectin ulex europaeus., Results: In early lesions, expression of PECAM-1, ICAM-1, ICAM-2, and P-selectin was similar to that in control samples, and VCAM-1 and E-selectin were induced in vascular endothelium. In advanced lesions, immunostaining for adhesion molecules diminished or disappeared in luminal endothelium, whereas these molecules were clearly expressed in microvessels within and surrounding inflamed vessels. Staining in endothelia from vessels in a healing stage tended to be negative. A high proportion of infiltrating leukocytes expressed LFA-1 and VLA-4, and only a minority expressed L-selectin. No relationship between the expression pattern of adhesion molecules and clinical features, disease duration, or previous corticosteroid treatment was observed., Conclusion: Endothelial adhesion molecule expression in PAN is a dynamic process that varies according to the histopathologic stage of the vascular lesions. The preferential expression of constitutive and inducible adhesion molecules in microvessels suggests that angiogenesis contributes to the persistence of inflammatory infiltration in PAN.

The cutaneous form of polyarteritis nodosa in children is extremely rare. Findings are usually limited to the skin, muscles and joints. It has a benign but often chronic course. We describe an 8-y-old girl with cutaneous PAN, with extensive livedo reticularis on lower and upper extremities, tender subcutaneous nodules, arthralgia and right ankle swelling. Skin biopsy revealed vasculitis of small and medium-sized blood vessels characterized by fibrinoid necrosis. The use of prednisolone resulted in clinical improvement initially, but recurrence occurred during tapering. She showed marked improvement with additional high dose methyl prednisolone monthly.

This case report reviews the unique development of a vasculitic syndrome involving medium-sized arteries in a man with chronic myelomonocytic leukemia (CMMoL). This case has many features in common with cutaneous polyarteritis nodosa (CPAN), and this may represent the first instance in which CPAN developed in the setting of CMMoL.

Objective: To investigate the phenotype of infiltrating cells in classic lesions of polyarteritis nodosa (PAN)., Methods: Twenty-one muscle and 10 sural nerve biopsy samples from 24 patients with systemic PAN were studied using avidin-biotin-peroxidase and alkaline phosphatase-anti-alkaline phosphatase immunohistochemical techniques., Results: The inflammatory infiltrates consisted mainly of macrophages (41%) and T lymphocytes (41%), particularly of the CD4+ subset. Granulocytes were present in varying quantities (0-45%) and were more abundant in heavily infiltrated vessels and in those with fibrinoid necrosis. Dendritic cells could be identified in 4 samples. Proliferating and interleukin-2 receptor-expressing cells, present in 71% and 79% of the patients, respectively, were more frequent in untreated patients., Conclusion: T cell-mediated immune mechanisms may play a role in the development and perpetuation of PAN lesions.

We describe the histopathologic criteria for the diagnosis of 7 selected vasculitis syndromes: polyarteritis nodosa, Churg-Strauss syndrome, Wegener's granulomatosis, hypersensitivity vasculitis, Henoch-Schönlein purpura, giant cell (temporal) arteritis, and Takayasu arteritis. The criteria apply to the stereotypical cases in each category; they were formulated after a review of submitted biopsy material from 278 of the 1,000 patients entered into the American College of Rheumatology Vasculitis Study Registry, and from prior experience with the pathologic diagnosis of vasculitis in 1,079 nonregistry patients.

1. This study examined the effect of various antihypertensive agents on the development of polyarteritis nodosa lesions along the mesenteric artery system over a 10 week period after renal artery clipping in uninephrectomized rats (lKlC). 2. Of the agents, only hydralazine, enalapril and diltiazem significantly inhibited systolic blood pressure (SBP) rise over the 10 week period (P less than 0.001). 3. All agents except hydralazine reduced the severity of arteritic lesions compared with lKlC rats, but only with enalapril (P less than 0.001), nifedipine (P less than 0.001), diltiazem (P less than 0.005), propranolol (P less than 0.001) and reserpine (P less than 0.05) was this reduction statistically significant. 4. There was a positive correlation between the degree of arteritic change and SBP, but the correlation coefficient was neither high (r = 0.68) nor highly significant (P = 0.03, d.f. = 9). On examining the data, this was due on the one hand to nifedipine, propranolol and reserpine reducing the severity of lesions without significantly inhibiting SBP, and on the other to hydralazine reducing SBP without significantly affecting the extent of arteritic change. 5. These findings suggest that factors other than mere SBP alone are involved in the pathogenesis of these arteritic lesions.

Systemic vasculitis includes a broad spectrum of disorders that may involve blood vessels of any size in any organ system. Systemic vasculitis is associated with immunopathogenic mechanisms. Sixteen temporal bones from eight persons were studied to determine histopathologic changes that occur in systemic vasculitis. Three persons had Wegener's granulomatosis, two had polyarteritis nodosa, and three had systemic lupus erythematosus. Otitis media was seen in 15 ears, with ten ears showing chronic middle ear changes and two showing fibrotic inner ear changes. In Wegener's granulomatosis, granulation tissue was observed around the eustachian tube and protympanum, and in polyarteritis nodosa, inflammatory cell infiltrate and thickened blood vessels were observed around the facial nerve. Although sensorineural hearing loss has been described clinically in systemic lupus erythematosus, the present report describes findings in temporal bones, including severe fibrosis and new bone formation throughout the inner ear.

Twenty cases diagnosed as cutaneous polyarteritis nodosa (CPN) and confirmed by skin biopsy over the last 17 years were reviewed in our department. Based upon their clinical features, laboratory findings, and long-term observation of the disease course, they were divided into three groups. 1) Group 1 comprised 16 cases which were classified as the mild cutaneous form. The disease was confined to the skin with occasional involvement of peripheral nerves and skeletal muscles of the affected extremity. They generally followed a benign course. 2) Group 2 comprised 2 cases classified as the severe form. Despite severe clinical manifestations and several abnormal laboratory findings, the disease was limited to the skin, muscles, and peripheral nerves without any visceral involvement over follow-up periods of 11 years and 5 years, respectively. 3) Group 3 comprised 2 cases of the progressive form; in these the disease had begun with a cutaneous lesion and progressed to the systemic form after 19 and 18 year periods of recurrent episodes of cutaneous lesions, respectively. One died of gastrointestinal bleeding. In group 3, serum antinuclear antibodies and rheumatoid factor were positive. The autoimmune mechanism seems to play a role in this group. It is clear from the results of this study that not all patients whose vasculitic lesions are apparently limited to the skin remain in a benign course. Long-term follow-up is essential.

A patient with polyarteritis nodosa developed necrotizing enterocolitis, as indicated by pneumatosis intestinalis seen on computed tomographic scans of the abdomen. Despite immunosuppressive therapy and concomitant resolution of the intramural and portal venous gas and general clinical improvement, on 2 occasions (between 20 and 30 days later) the patient developed bowel infarctions and perforations that necessitated bowel resection. Leaks developed at anastomotic sites, but were not closed surgically. However, these sites and the lower quadrants of the abdomen were drained, and the patient was given total parenteral nutrition. Over a 2-month period the patient completely recovered from this nearly always fatal gastrointestinal complication of polyarteritis nodosa. The medical, surgical, and radiographic approach we used may be applicable to the management of similar cases in the future.

The clinical and general histopathologic manifestations of systemic vasculitis of the polyarteritis nodosa type are well known. Although hearing loss associated with polyarteritis nodosa has been reported, only two temporal bone studies are available. The findings in a 60-year-old man with well-documented hearing loss who had rheumatoid arthritis, polyarteritis nodosa, and otosclerosis are presented. Polyarteritis nodosa extensively involved the subarcuate arteries and arteries of the facial canal. There were decreased nerve fibers to and sensory cells in the crista of the semicircular canals and macula of the utricle and saccule. Focal and diffuse atrophy of the stria vascularis and decreased cellularity in the spiral prominence and ligament were present. There was a loss of outer hair cells. Otosclerosis involved the left and right oval window niches (bilateral stapedectomy had been performed). There was a small Antoni type A neuroma of the superior division of the vestibular nerve on the left.

Two patients with arthritis of the knee joints associated with cutaneous polyarteritis have been followed for 20 and 5 years. The arthritis is characterized by mild to moderate pain and stiffness and inflammatory joint effusions with predominantly polymorphonuclear leukocytes. Despite its chronicity, there has been no clinical or radiologic evidence of joint destruction. Necrotizing inflammation was seen in arteries of the deep skin but not in the small vessels observed in the synovial biopsy specimens.

The clinical and pathologic findings of 2 infants and 7 older children with polyarteritis nodosa who were autopsied are reported. The most frequent clinical features included prolonged high fever, skin rash, abdominal symptoms, leukocytosis, proteinuria, and signs of either cardiac or renal failure. The 2 infants died of cardiac arrest, whereas renal or neurologic involvement was the most common cause of death in the older children. A consistent finding at autopsy was arteritis of the epicardial coronary arteries.