Polyarteritis nodosa
• A systemic necrotizing vasculitis.
• With aneurysm formation.
• Medium or small arteries.
• Historically as the first noninfectious cause of vascular damage.
1866, Kussmaul and Maier’s
• At least one third of children with PAN, have a more limited form, restricted largely to the skin and joints.
• is most commonly associated with hepatitis B or C infections.
• pediatric PAN is quite rare,
• peaks at 9 to 10 years of age,
• No clear genetic association.
• association with familial Mediterranean fever (FMF).
• Up to 1% of FMF patients develop PAN, milder than idiopathic disease.
Cutaneous PAN
• limited to skin and the musculoskeletal system.
• Post streptococcal pharyngitis.
• Livedo reticularis,
• maculopapular rash,
• painful skin nodules, panniculitis,
• brawny edema,
• Arthritis mostly affect the knees and ankles.
• Acute-phase reactants may be normal or elevated,
• Constitutional symptoms are generally mild.
• Tends to persist or relapse,
• Many patients require steroid-sparing agents for long-term management.
• Methotrexate or other immunosuppressive agents;
• TNF inhibitors have been reported to be effective, as well
• Penicillin prophylaxis
Systemic PAN
• Any muscular artery.
• Constitutional symptoms.
• A vast array of organ dysfunction.
• Palpable purpura, livedo, necrotic dermal lesions.
• Abdominal pain, arthritis/arthralgia, myositis/myalgia,
• Renovascular hypertension,
• Neurologic deficits,
• Pulmonary disease, coronary arteritis.
PAN DD
• Systemic-onset juvenile rheumatoid arthritis,
• KD,
• Dermatomyositis.
• Glomerulonephritis typically is not a feature of this condition.
Laboratory evaluation
• Anemia, leukocytosis, thrombocytosis, and elevated ESR, CRP, and immunoglobulins.
• A positive ANCA generally indicates pauci-immune glomerulonephritidies rather than PAN.
• Proteinuria, hematuria, and increases in serum urea nitrogen and creatinine levels are also common findings.
• Complement levels are normal.
The diagnosis usually requires tissue biopsy or radiologic documentation of vasculitis.
• Typical beading of vessels.
• Alternating areas of vascular narrowing and dilatation that give PAN its name.
• Pathologically this manifestation corresponds to segmental vascular involvement with nodule and aneurysm formation resulting from panmural fibrinoid necrosis.
• No overt complement or immunoglobulin deposition is seen.
Treatment
• High-dose steroids.
• Other immunosuppressive agents,
• daily oral or monthly intravenous doses of cyclophosphamide,
• Azathioprine, methotrexate, IVIG, and,
• TNF-inhibitors,
• A 4-year mortality rate under 5%.
Takayasu arteritis
• TA is the third most common form of childhood vasculitis
• The cause of TA remains unknown,
• a primarily T-cell–mediated mechanism
• granulomatous changes progressing from the vascular adventitia to the media,
• indistinguishable from those seen in giant cell arteritis and temporal arteritis
The diagnosis of TA is based on the distribution of involvement
• primarily the aorta and its branches—
• and the young age of patients,
• typically under 40 years
Takayasu arteritis
• childhood disease has been reported as early as the first year of life
• significant preponderance of female patients in children with TA,
• mean age of onset was 11.4 years,
• two thirds of the patients were female
Takayasu arteritis
• Signs and symptoms.
– hypertension,
– cardiomegaly,
– elevated ESR,
– fever, fatigue, palpitations,
– vomiting, nodules, abdominal pain,
– arthralgia,
– claudication,
– weight loss, and chest pain.
• The delay in diagnosis in children was 19 months.
Angiography the standard method used for diagnosis.
• CT and MR angiograms have proven to be as useful as traditional angiograms.
• MRI has the added advantage of revealing evidence of ongoing vessel wall inflammation.
• Laboratory markers may be entirely normal despite ongoing inflammation
• Steroids
• cyclophosphamide,
• methotrexate,
• Azathioprine
• TNF-inhibitors
Primary angiitis of the central nervous system
• one of the most challenging diseases a physician might face,
• systemic manifestations of the disease are usually absent,
• acute-phase reactants are typically normal,
• and examination of CSF might be unrevealing as well
• high level of suspicion when children have even scanty suggestion of a vasculitis.
• A recent review 62 patients with childhood PACNS (cPACNS)
• Headache (80%) and
• focal neurologic deficits (78%)
• hemiparesis in 62%.
• Normal MRI together with normal CSF have high negative predictive value for cPACNS.
• 5% to 10% of cases of cPACNS, only a meningeal and brain biopsy proved the vasculitis.
• PACNS may be rapidly progressive and neurologically devastating,
Treatment invariably includes
• corticosteroids and a potent immunosuppressive agent, usually cyclophosphamide.
• methotrexate or azathioprine for maintenance therapy, excellent results
