Clinical and Pathological Features of Microscopic Polyangiitis in 20 Children

Cerebrovascular involvement in systemic childhood vasculitides

Pediatric vasculitides sometimes involve central nervous system (CNS). The manifestations are diverse, ranging from headache, seizures, vertigo, ataxia, behavioral changes, neuropsychiatric symptoms, consciousness disorders, and even cerebrovascular (CV) accidents that may lead to irreversible impairment and even death. Stroke, on the other hand despite the great progress in prevention and treatment, is still one of the leading causes of morbidity and mortality in the general population. The aim of this article was to summarize CNS manifestations and CV issues observed in primary pediatric vasculitides and the current knowledge of etiology and CV risk factors, preventive strategies, and therapeutic options in this target patient population. Pathophysiological links reveal similar immunological mechanisms involved in both pediatric vasculitides and CV events with endothelial injury and damage being the central point. From the clinical point of view, CV events in pediatric vasculitides were associated with increased morbidity and poor prognosis. If damage has already occurred, the therapeutic approach consists of good management of the vasculitis itself, antiplatelet and anticoagulation therapy, and early rehabilitation. Risk factors for acquiring cerebrovascular disease (CVD) and stroke, particularly hypertension and early atherosclerotic changes, already begin in childhood, with vessel wall inflammation contributing itself, once more emphasizing that appropriate preventive measures are certainly necessary in pediatric vasculitis population to improve their long-term outcome.

Vasculitis and Kidney Disease

Pediatric vasculitis is a complex group of disorders that commonly presents with multisystem involvement. Renal vasculitis can be isolated to the kidneys or can occur as part of a broader multiorgan vasculitis. Depending on severity, renal vasculitis may present as acute glomerulonephritis (AGN) often associated with hypertension and sometimes with a rapidly deteriorating clinical course. Prompt diagnosis and initiation of therapy are key to preserving kidney function and preventing long-term morbidity and mortality. This review focuses on the clinical presentation, diagnosis, and treatment objectives for common forms of renal vasculitis seen in pediatric patients.

Atypical Neurological Manifestation in Childhood Microscopic Polyangiitis: A Case Report and Review of Literature

Microscopic polyangiitis (MPA), a systemic necrotizing vasculitis of small vessels, is primarily associated with necrotizing and crescentic glomerulonephritis and pulmonary capillaritis. Neurological involvement, particularly of the central nervous system (CNS) is scarcely observed. The diversity of CNS symptoms could puzzle the diagnosis causing delays in treatment and potentially having a considerable effect on patient's quality of life or even death. The aim of this case report is to highlight the unusual manifestation of MPA in order to raise awareness of this orphaned disease among pediatricians or even pediatric rheumatologists and neurologists.

CASE REPORT

Herein we report the case of a 13-year-old Thai girl diagnosed with MPA presented with rapidly progressive glomerulonephritis (RPGN). Renal biopsy was performed demonstrated crescentic glomerulonephritis with negative immunofluorescence and positive titer of myeloperoxidase (MPO) antibody. Pulse methylprednisolone (MP) and cyclophosphamide (CYC) as well as plasmapheresis were initiated. Despite treatment with prednisolone (45 mg/day) and monthly CYC for two doses, she experienced a brief generalized tonic-clonic seizure during the follow-up period. The potential differential diagnosis of new-onset neurological manifestation contains infection owing to the immunocompromised status of the patient and CNS vasculitis as a result of the disease itself. Lumbar puncture was performed, and cerebrospinal fluid analysis demonstrated pleocytosis with negative infectious panel. Contrast magnetic resonance imaging studies of the brain showed multifocal patchy T2/FLAIR-hyperintense lesions in the cerebral as well as cerebellum regions, and irregular narrowing along the V4 segment of the right vertebral artery was demonstrated in magnetic resonance angiography. In the presence of CNS vasculitis, pulse MP and CYC were provided. The symptom of nervous system has progressively improved.

CONCLUSION

In our case, MPA revealed RPGN with neurological manifestation. Despite the fact that it is scarcely reported, CNS vasculitis is one of the organ-threatening symptoms. To improve patient morbidity and mortality, multidisciplinary care teams with prompt diagnosis and treatment are highly recommended.

CNS limited ANCA-associated vasculitis presenting as an isolated intraparenchymal mass

The authors report a 34-year-old male with antineutrophil cytoplasmic autoantibody (ANCA) associated vasculitis (AAV) which only involved the central nervous system and presented with an isolated mass in the left parietal lobe. Constitutional symptoms were lacking and the only symptom was progressive right-sided hemiparesis. Pathology suggested necrotizing vasculitis without eosinophils and granulomas. Cytoplasmic ANCA was elevated to 103.9 IU/ml (>5 times the upper limit) in serum. He obtained a regression following treatment of cyclophosphamide and steroids. Prompt diagnosis of AAV is essential since early and aggressive initiation of immunosuppressive therapy can avoid further neurological sequelae.

Clinical features and outcomes of anti-neutrophil cytoplasmic autoantibody-associated vasculitis in Chinese childhood-onset patients

Data on anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) are limited in children. This study is to determine the clinical features and outcomes of childhood-onset AAV. A retrospective study was performed on patients who were diagnosed with AAV before 18 years old in Xiangya Hospital. Their medical records were analyzed by retrospective review. Sixteen patients were diagnosed with AAV before 18 years old in the past 9 years, with an average age of 13.3 ± 3.3 years and 13 of them were female. There were 15 patients with microscopic polyangiitis (MPA) and 1 with Wegener's granulomatosis. The interval between onset of disease and diagnosis of AAV was 2 (1.5-3) months. Most patients (15/16, 93.8%) had multi-organ involvement, and all patients had renal involvement with 7 (43.8%) patients requiring dialysis at presentation. Eleven patients underwent a renal biopsy, of which mixed class and sclerotic class were the most two common histological types. All patients received immunosuppressive therapy for induction therapy including intravenous administrations of methylprednisolone (MP) pulse therapy for 8 patients. 8 patients (50%) achieved remission after induction therapy. After a median follow-up of 46.3 ± 36.1 months, nine (56.3%) patients progressed to end-stage renal disease (ESRD) and 5 (31.3%) patients died. Childhood-onset AAV showed similar clinical and pathological features compared to those of adults, except that it usually occurs in girls. The most commonly involved organ was the kidney, and it had a high risk of progression to ESRD. Early diagnosis and initiation of appropriate immunomodulatory therapy would be important to improve outcomes.

Epidemiology and clinical features of childhood-onset anti-neutrophil cytoplasmic antibody-associated vasculitis: a clinicopathological analysis

BACKGROUND

This study was performed to determine the clinical features and outcomes of childhood-onset anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), particularly microscopic polyangiitis (MPA).

METHODS

A retrospective Japanese multicenter study was performed in patients diagnosed with AAV before 16 years of age.

RESULTS

Of 49 patients with AAV, 36 were female. The diagnoses were as follows: MPA (n = 38, 78%), granulomatosis with polyangiitis (GPA; n = 9, 18%), eosinophilic granulomatosis with polyangiitis (EGPA; n = 1, 2%), and other (n = 1, 2%). The median age at onset was 10.7 years, and median time to diagnosis was 2.0 months. Twenty-seven (55%) patients were identified through a school urinary screening program. Initial symptoms included fever and fatigue (45%), and renal (71%), pulmonary (29%), ocular (20%), and mucocutaneous involvement (22%). Although 27 (55%) patients achieved remission and none had died at the last follow-up, at least one recurrence occurred in 13 (48%) patients after a median of 48 months and was more common in patients with GPA (P < 0.01). After a median follow-up of 43 months, seven (14%) patients (all with MPA) progressed to end-stage renal disease (ESRD).

CONCLUSIONS

Childhood-onset AAV has an estimated prevalence of 3.41-4.28 per million children and is characterized by female predominance and high frequency of detection in school urinary screening programs. More than 10% of patients with childhood-onset AAV still progress to ESRD without achieving remission. Histological chronicity is a factor associated with ESRD.

From fibrosis to diagnosis: a paediatric case of microscopic polyangiitis and review of the literature

We herein describe a case of a 6-year-old girl diagnosed with microscopic polyangiitis (MPA) after a long diagnostic process demanding the cooperation of paediatric respiratory medicine specialists, rheumatologists, nephrologists and radiologist. First symptoms of MPA were observed after Mycoplasma pneumoniae infection and included persistent crepitations at the basis of both lungs and mild haematuria. CT imaging showed features of lung fibrosis, renal biopsy was indicative of mesangial proliferative glomerulonephritis, in the skin biopsy features of microscopic polyangiitis were described. In the laboratory tests pANCA antibodies specific for myeloperoxidase (MPO) were present in high titer. MPA with initial features of lung fibrosis is an unusual presentation of this rare disease, usually observed in adult population. This unique case illustrates the diagnostic and therapeutic challenges in paediatric vasculitis patients with an unusual initial presentation in the form of interstitial lung disease. In the manuscript we also discuss the possible aetiology of lung fibrosis in microscopic polyangiitis MPA and provide the review of the current literature on the topic of childhood-onset MPA.

Primary Vasculitis in Childhood: GPA and MPA in Childhood

Childhood onset anti-neutrophilic cytoplasmic antibody (ANCA) associated vasculitis (AAV) is a rare group of primary systemic vasculitides affecting medium and small blood vessels. AAV includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), and renal limited ANCA vasculitis. These disorders are associated with severe clinical manifestations, frequent relapses and a high cumulative morbidity, and often present with multisystem involvement. Renal involvement is common in the pediatric age group, characterized by pauci-immune necrotizing and crescentic glomerulonephritis which frequently progresses to chronic kidney disease in adulthood. ANCAs against proteinase 3 (PR3-ANCA) or myeloperoxidase (MPO) (MPO-ANCA) remain the hallmark of AAV and are integral to the disease pathogenesis. Newer understanding of neutrophil extracellular traps and complement activation have provided better insights into disease pathogenesis. A pediatric vasculitis working group has developed and validated childhood vasculitis classification criteria and disease activity and damage scores. No specific pediatric treatment recommendations exist due to rare nature of the illness in pediatric population. Smaller case series have been published on the efficacy of adult treatment regimens in pediatric patients. The prognosis often remains guarded with frequent relapses and a high cumulative morbidity. The aim of this article is to provide a comprehensive review on pediatric AAV with a focus on recent observations regarding epidemiology, disease pathogenesis, treatment, and prognosis.

Childhood Vasculitis

The term vasculitis covers heterogeneous disorders that share the presence of inflammation of blood vessel walls. Immune cell infiltrates can vary significantly and involve granulocytes or mononuclear cells. Vasculitis can be a symptom of other underlying disorders or the underlying cause of organ specific or systemic disease. Classification of childhood vasculitis is based on clinic, the size of predominantly affected vessels, and the histopathology of inflammatory infiltrates. Timely and accurate diagnosis and (where necessary) treatment initiation determine disease progression and outcomes. In light of new developments and the identification of autoinflammatory conditions with vasculitis, new classification tools may be discussed.

Childhood- versus adult-onset ANCA-associated vasculitides: A nested, matched case-control study from the French Vasculitis Study Group Registry

OBJECTIVE

To investigate differences between childhood-onset ANCA-associated vasculitides (cAAVs) and matched adult-onset controls (aAAVs).

METHODS

cAAV clinical pictures at onset and outcomes were compared to a randomly selected sample of aAAV patients from the French Vasculitis Study Group Registry. Cases and controls were matched for AAV (granulomatosis with polyangiitis [GPA], microscopic polyangiitis [MPA] or eosinophilic granulomatosis with polyangiitis [EGPA]), sex and year of enrollment. Medications, disease activity and damage were prospectively recorded. Kaplan-Meier curves and the log-rank test were used to analyze case-vs.-control differences for predefined outcomes.

RESULTS

Comparing 35 cAAVs (25 GPA, 4 MPA, 6 EGPA) to 151 aAAVs (106 GPA, 17 MPA, 28 EGPA), their respective median follow-up durations were 71 and 64months (P=0.49), and, at baseline, children had less frequent myalgias (P=0.005) and peripheral neuropathy (P<0.001) but were more frequently febrile (P<0.05). Rates of renal involvement were comparable (13 [37%] cAAVs vs. 73 [48%] aAAVs; P=0.31). Initial GPA-associated ischemic abdominal pain and nasal cartilage damage were more common in cAAVs than aAAVs (P<0.05). During follow-up, the cAAV relapse rate was higher (24.5 vs. 18.7 flares per 100 patient-years; P<0.05) and, at last visit, cases had accumulated more damage, mostly ear, nose & throat sequelae (P=0.001), associated with longer maintenance therapy (P=0.03), than aAAV controls. Four (11.4%) cAAV and 13 (8.6%) aAAV patients died (P=0.53).

CONCLUSION

cAAVs are severe diseases, characterized by a higher relapse rate, more accrued damage and longer maintenance therapy than for aAAVs.

Childhood-onset granulomatosis with polyangiitis and microscopic polyangiitis: systematic review and meta-analysis

BACKGROUND

The data from cohorts of childhood-onset granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) remain scarce and heterogeneous. We aimed to analyse the features at presentation, therapeutic approaches and the disease course of these rare diseases.

METHODS

Electronic searches of Medline and the Cochrane Central Register of Controlled trials database were conducted. We also checked the reference lists of the studies included and other systematic reviews, to identify additional reports. We included all cohorts, cross-sectional studies or registries reporting features at presentation or outcomes in patients with a diagnosis of childhood-onset GPA or MPA (age <18 years). The pooled prevalence of clinical manifestations at presentation, ANCA and induction therapies for GPA and MPA was calculated.

RESULTS

We reviewed 570 full texts and identified 14 studies on GPA and 8 on MPA. Childhood-onset GPA and MPA occurred predominantly in female subjects during adolescence. For GPA, ear-nose-throat (ENT) disease (pooled prevalence 82 % [95 % CI 78-87]), constitutional symptoms (73 % [95 % CI 55-88]), renal (65 % [95 % CI 49-79]), and lower respiratory tract (61 % [95 % CI 48-74]) manifestations were the most frequently reported at presentation. Renal disease was a hallmark of MPA (94 % [95 % CI 89-97]). ANCA were detected in >90 % of children with GPA or MPA. Combined corticosteroids and cyclophosphamide was the most frequently used first remission-inducing treatment for GPA (76 % [95 % CI 69-82]) and MPA (62 % [95 % CI 20-96]). Relapses occurred more frequently in GPA (67-100 %) than in MPA (25-50 %). The leading causes of death were the disease itself, and infections.

CONCLUSIONS

Childhood-onset MPA and GPA remain severe diseases with frequent relapses and a high cumulative morbidity. Survival and disease-free survival need to be improved.

Comparing Presenting Clinical Features in 48 Children With Microscopic Polyangiitis to 183 Children Who Have Granulomatosis With Polyangiitis (Wegener's): An ARChiVe Cohort Study

OBJECTIVE

To uniquely classify children with microscopic polyangiitis (MPA), to describe their demographic characteristics, presenting clinical features, and initial treatments in comparison to patients with granulomatosis with polyangiitis (Wegener's) (GPA).

METHODS

The European Medicines Agency (EMA) classification algorithm was applied by computation to categorical data from patients recruited to the ARChiVe (A Registry for Childhood Vasculitis: e-entry) cohort, with the data censored to November 2015. The EMA algorithm was used to uniquely distinguish children with MPA from children with GPA, whose diagnoses had been classified according to both adult- and pediatric-specific criteria. Descriptive statistics were used for comparisons.

RESULTS

In total, 231 of 440 patients (64% female) fulfilled the classification criteria for either MPA (n = 48) or GPA (n = 183). The median time to diagnosis was 1.6 months in the MPA group and 2.1 months in the GPA group (ranging to 39 and 73 months, respectively). Patients with MPA were significantly younger than those with GPA (median age 11 years versus 14 years). Constitutional features were equally common between the groups. In patients with MPA compared to those with GPA, pulmonary manifestations were less frequent (44% versus 74%) and less severe (primarily, hemorrhage, requirement for supplemental oxygen, and pulmonary failure). Renal pathologic features were frequently found in both groups (75% of patients with MPA versus 83% of patients with GPA) but tended toward greater severity in those with MPA (primarily, nephrotic-range proteinuria, requirement for dialysis, and end-stage renal disease). Airway/eye involvement was absent among patients with MPA, because these GPA-defining features preclude a diagnosis of MPA within the EMA algorithm. Similar proportions of patients with MPA and those with GPA received combination therapy with corticosteroids plus cyclophosphamide (69% and 78%, respectively) or both drugs in combination with plasmapheresis (19% and 22%, respectively). Other treatments administered, ranging in decreasing frequency from 13% to 3%, were rituximab, methotrexate, azathioprine, and mycophenolate mofetil.

CONCLUSION

Younger age at disease onset and, perhaps, both gastrointestinal manifestations and more severe kidney disease seem to characterize the clinical profile in children with MPA compared to those with GPA. Delay in diagnosis suggests that recognition of these systemic vasculitides is suboptimal. Compared with adults, initial treatment regimens in children were comparable, but the complete reversal of female-to-male disease prevalence ratios is a provocative finding.

Clinical features of children with pulmonary microscopic polyangiitis: report of 9 cases

Kidneys and lungs are the most common organs involved in microscopic polyangiitis (MPA). A retrospective analysis of pediatric MPA patients with pulmonary lesions over the past 10 years was performed to investigate clinical features of MPA in children with pulmonary lesions. There were 9 patients enrolled in our study, including 2 boys and 7 girls, with a median age of 6.6 years at the time of disease onset and a median disease course of 2 months. All of the patients exhibited tachypnea, and 7 exhibited cough and hemoptysis. The most common presentation on pulmonary imaging was ground glass or patchy shadows, which were observed in 6 cases. Seven patients manifested with hematuria and proteinuria, with renal histopathology of fibrinoid necrosis/exudation of the glomerular capillaries. All of the patients presented with normocytic normochromic anemia. Of the 9 patients, 7 were positive for perinuclear antineutrophil cytoplasmic antibody (p-ANCA) and/or myeloperoxidase (MPO), and 2 were positive for p-ANCA/MPO and cytoplasmic ANCA/proteinase 3. Eight patients had normal complement 3 (C3) levels, and one had an elevated C3 level. Five of the 9 patients were positive for antinuclear antibody ANA, and 4 were positive for double strand DNA (ds-DNA) antibody (3 were positive for both). The 7 patients who exhibited renal involvement received steroid plus cyclophosphamide (CTX) treatment. Of these patients, 4 achieved various degrees of remission, 2 were at the beginning of induction therapy, and one was lost to follow-up. Two patients with isolated pulmonary involvement received steroid plus leflunomide treatment and achieved complete remission. Diffuse alveolar hemorrhage was the most frequent presentation of lung involvement in children with MPA, and tachypnea, cough, hemoptysis and anemia were the common clinical symptoms. The majority of these patients exhibited hematuria, proteinuria and renal insufficiency. The efficacy of steroid plus CTX or leflunomide was evident in these patients.