Erythropoietic protoporphyria (EPP) is an inherited disorder of heme synthesis caused by deficiency of the mitochondrial enzyme ferrochelatase. EPP in humans is associated with liver disease, hypertriglyceridemia, and a low level of high density lipoprotein (HDL) cholesterol. To explore consequences of ferrochelatase deficiency in lipid metabolism, we have analyzed hepatic lipid content and plasma lipoprotein levels in chow-fed BALB / c mice homozygous ( fch/fch ) or heterozygous ( fch/ ؉ ) for a point mutation in the ferrochelatase gene and in wild-type controls ( ؉ / ؉ ). Livers of fch/fch mice show bile duct proliferation and biliary fibrosis, but bile formation is not impaired. The free cholesterol content of fch/fch livers is significantly increased when compared with fch/ ؉ and ؉ / ؉ livers. Plasma cholesterol in fch/fch mice (9.9 ؎ 6.4 mM) is elevated when compared with fch/ ؉ and ؉ / ؉ mice (2.9 ؎ 0.2 and 2.5 ؎ 0.3 mM, respectively), because of an increased cholesterol content in the very low density lipoprotein-sized fractions, whereas HDL cholesterol is reduced. The ratio of cholesteryl ester to free cholesterol is 4.3 ؎ 0.6, 3.3 ؎ 0.3, and 0.3 ؎ 0.1 in the plasma of ؉ / ؉ , fch/ ؉ , and fch/fch mice, respectively. The latter is not due to reduced lecithin:cholesterol acyltransferase activity in plasma of fch/fch mice but to the presence of lipoprotein-X (Lp-X), a particle composed of biletype lipids usually seen only in cholestatic conditions. Expression of mdr2 , essential for biliary phospholipid / cholesterol secretion, is increased in fch/fch livers. In spite of this, biliary phospholipid / cholesterol secretion is reduced relative to that of bile salts. It is postulated that an inability of bile salts to stimulate lipid secretion adequately leads to formation of Lp-X in this noncholestatic condition. Distinct atherosclerotic lesions were found in aged fch/fch mice.Thus, ferrochelatase deficiency in mice leads to liver disease associated with altered hepatic lipid metabolism, a characteristic hyperlipidemia, and development of atherosclerosis. Erythropoietic protoporphyria (EPP) is an inherited disorder of heme synthesis caused by deficiency of the mitochondrial enzyme ferrochelatase (EC 4.99.1.1), responsible for insertion of iron into protoporphyrin (PP) (1). Impaired ferrochelatase activity in humans with EPP results in increased PP concentrations in erythrocytes, blood, liver, and feces (1). Skin lesions after exposure to sunlight represent the hallmark of EPP. Liver disease is one of the complications that may occur in patients with EPP but hepatic manifestations of EPP are diverse (1, 2). About 40 different mutations in the human ferrochelatase gene have been described so far (3). It appears that only mutations that give rise to severe deficiencies of enzyme activity predispose to development of liver disease for which transplantation is indicated (4).Elevated plasma triglyceride levels and low levels of high density lipoprotein (HDL) cholesterol have been reported in EPP patients (...

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This article describes nutrition implications of pediatric dilated cardiomyopathy leading to heart transplantation with a focus on nutritional management of patients during the waiting time for a donor organ and the inpatient postoperative period. Optimization of nutritional status is essential during these periods as weight loss and malnutrition contribute to muscle atrophy, decreased functional capacity, reduced immune function, and prolonged hospital stay. Nutrition implications of heart failure vary with patient's age and degree of symptoms. Infants may have increased caloric needs and poor feeding often due to tachypnea. Older children, 1-18 years, may have decreased appetite, abdominal pain, and vomiting. Ventricular assist devices or extracorporeal membrane oxygenation, necessary to sustain life in some cases, have additional nutrition implications related to wound healing from insertion of the device and device-related complications that can include pancreatitis and the need for total parenteral nutrition. Once symptomatic heart failure is relieved and heart transplant occurs, caloric needs often decrease while interest in eating can increase profoundly, changing the overall nutrition diagnosis and the need for nutrition support. A case series involving an infant, a young child, and an adolescent is presented to illustrate nutritional challenges and interventions for pediatric patients awaiting heart transplant and the inpatient postoperative period.

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