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patients and is associated with a poor prognosis, with 44% survival at 1 year and less than 25% survival at 5 years.318 The secondary form may be clinically apparent in the second decade or earlier, depending on the frequency of transfusions There is widespread deposition of iron in the liver, spleen, pancreas, gonads, skin, and heart, which leads to the clinical manifestations The classic triad consists of hepatic cirrhosis, bronze pigmentation of the skin, and DM Splenomegaly is present in approximately half the patients with idiopathic hemochromatosis and in virtually every patient with β-thalassemia Cardiac involvement results from excessive deposits of hemosiderin in the heart This produces a dilated cardiomyopathy with cardiac failure A restrictive cardiomyopathy has also been described.319 The heart is rusty-brown at postmortem, with dilation of all cardiac chambers Concentration of iron is greater in the subepicardial part of the heart, therefore limiting the use of endomyocardial biopsies.320 Iron in the form of hemosiderin initially adopts a perinuclear distribution and then extends peripherally as the amount of deposits increases These are greater in the ventricles than in the atriums and the conduction tissues.321 Low-voltage QRS complexes are seen electrocardiographically with nonspecific ST-segment and T-wave changes A prolonged QT interval may be present, and there may be evidence of right or left ventricular hypertrophy Disturbances of rhythm are common and include atrial and ventricular premature contractions, supraventricular and ventricular tachycardias, and varying degrees of atrioventricular block Cardiac enlargement and signs of cardiac failure, when present, are seen in the chest radiograph Echocardiography shows increased left ventricular mural thickness, increased left ventricular and left atrial dimensions, and a reduction in fractional shortening and ejection fraction.322 Laboratory studies should include measurements of plasma iron, ferritin, and saturation of transferrin These are typically elevated Measurement of the content of iron in samples obtained by needle biopsy of the liver allows accurate estimations of total body iron Advance in cardiac magnetic resonance techniques allow for noninvasive estimates of cardiac iron loading.323 Malignant hepatoma is an important late complication in older patients Removal of iron by repeated venesection or by chelation with desferioxamine in secondary iron overload may reverse cardiac manifestations except for the disturbances of conduction.324 Symptomatic heart block requires insertion of a pacemaker Autoimmune Diseases Juvenile Idiopathic Arthritis Juvenile idiopathic arthritis (JIA) is the most common form of chronic juvenile arthritis It is typically characterized by the absence of positive serologic tests The disease is divided into several forms based on the principal features and onset Patients with systemic-onset idiopathic arthritis, or Still disease, frequently have a quotidian febrile pattern accompanied by an evanescent rash, hepatosplenomegaly, and generalized lymphadenopathy Arthritis may or may not be present Pleuritis with interstitial pulmonary disease is frequent The most common cardiac manifestation is pericarditis.325 Polyarticular disease is characterized by symmetric involvement of the wrist, knee, and ankle joints The cervical spine is frequently affected Systemic manifestations are of a milder nature Rash, splenomegaly, and lymphadenopathy may be present The pauciarticular variety affects small children The joints involved are the knees, ankles, elbows, or wrists Systemic manifestations are infrequent Such patients are at risk of blindness from iridocyclitis This form has the best prognosis Pericarditis is the most common form of cardiac involvement, although myocarditis and endocarditis can occur as well.326 Pericarditis is best managed with antiinflammatories and, when necessary, pericardiocentesis Children with JIA may also be at risk for long-term cardiovascular disease There are conflicting data on the effect of JIA on lipid profiles and systemic blood pressure, but there is a trend toward lower high-density lipoprotein, higher triglycerides, and high normal blood pressure in JIA; therefore careful risk-factor management is important in the long term.327 Systemic Sclerosis (Scleroderma) Systemic sclerosis is a disorder of unknown etiology resulting in tightening and induration of the skin Visceral manifestations include gastrointestinal disease with dysphagia and reflux related to esophageal dysmotility; renal disease with azotemia, proteinuria and hypertension; pulmonary disease with interstitial fibrosis and pulmonary vascular changes leading to pulmonary arterial hypertension; and cardiac disease with conduction disturbances, myocardial fibrosis, coronary artery disease, and autonomic dysfunction.328,329 Close monitoring for the development of pulmonary hypertension is required, as this remains an important cause of morbidity and mortality, affecting up to one-sixth of patients.330 Cardiac involvement is often asymptomatic but found at autopsy in one-third of patients.331 Diastolic and systolic dysfunction is frequently seen by echocardiography even in asymptomatic patients Subtle evidence of right ventricular dysfunction may be an early sign of asymptomatic pulmonary hypertension and may allow for early treatment.332 Treatment of this complication includes currently available agents aimed at reducing pulmonary vascular resistance, coupled with cyclophosphamide to address the pulmonary interstitial fibrosis.333 Takayasu Arteritis Takayasu arteritis, also known as pulseless disease, is a chronic large-vessel vasculitis primarily affecting the aorta and the proximal arteries supplying the head and neck, along with the proximal pulmonary arteries Inflammation of the arterial walls leads to thickening, fibrosis, and ultimately stenosis with formation of thrombus Aortic aneurysms can also occur but are less frequent The disease often presents in adolescents or young adults with nonspecific symptoms of activation of the inflammatory system Consequently the diagnosis may be delayed until more overt evidence of the disease becomes manifest, including reduced pulses, hypertension, vascular bruits, and aortic valvar disease.334 Often the acute phase presents with systemic complaints: weight loss, fatigue and night sweats, and anorexia Treatment consists of immunosuppression with prolonged corticosteroid regimens Despite steroid regimens of 1 to 2 years, almost 50% of patients relapse during steroid weaning.335 When corticosteroids are not effective, more aggressive cytotoxic drugs can be used, such as cyclophosphamide, methotrexate, or azathioprine.336 Angioplasty or the implantation of stents is sometimes necessary for severe stenoses unresponsive to medical management Polyarteritis Nodosa Polyarteritis nodosa is a vasculitic syndrome affecting small- to medium-sized arteries, primarily in the kidney, skin, and gastrointestinal tract The