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M D Cappellini

Publications and source records attributed to M D Cappellini.

At least 19 recordsLinked to original sources

Co-existence of two functional mutations on the same allele of the human ferrochelatase gene in erythropoietic protoporphyria.

Erythropoietic protoporphyria (EPP) is an autosomal dominant disease with incomplete penetrance due to reduced activity of ferrochelatase (FECH), a mitochondrial enzyme that catalyzes the final step of the heme biosynthetic pathway. The clinical phenotype of EPP results from co-inheritance of a mutated allele and a wild-type low-expressed allele of the FECH gene. To date, more than 88 different mutations have been identified in the FECH gene of patients with EPP. There are evidences suggesting that an entire haplotype (-251G, IVS1-23T and IVS3-48C) reduces allele expression. In this study, we searched for the -251A/G, IVS1-23C/T and IVS3-48T/C polymorphisms in two unrelated Italian families with EPP. In all the patients, carrying the -250G>C mutation in the promoter region, the IVS3-48C on the other allele showed apparent homozygosity and absence of Mendelian segregation. By RNA and long polymerase chain reaction analysis, we identified a deletion of 5576 bp (g12490_18067), including exons 3 and 4, in cis with the -250G>C mutation in the promoter.

Adolescent↗

Lung function in beta-thalassemia patients: a longitudinal study.

Patients with beta-thalassemia often present with a restrictive pattern at pulmonary function tests (PFTs) due to several pathogenetic factors. However, the long-term evolution is unknown. We performed a longitudinal study of pulmonary function in asymptomatic, non-smoking patients with beta-thalassemia major and intermedia. We looked for temporal changes in lung function and characteristics that would predict the development of PFT abnormalities. In 1996, 18 patients with major beta-thalassemia (9 males and 9 females; age range: 18-35 years) and 11 patients with intermediate beta-thalassemia (5 males and 6 females; age range: 25-51 years) underwent clinical assessment and PFT, including body plethysmography and gas transfer study (carbon monoxide diffusion capacity, DL(CO)). Patients were reassessed in 2003. An echocardiographic evaluation was also obtained to exclude pulmonary hypertension. In 55.5% of major and 45.4% of intermediate beta-thalassemia patients, a restrictive pattern was found in 1996; in 2003 only 38.8 and 27.2% of patients, respectively, exhibited total lung capacities below the predicted values. DL(CO) was unchanged in both groups of patients, being reduced in 5 thalassemia major patients and within the normal range in intermediate patients. We conclude that asymptomatic patients with beta-thalassemia have a high prevalence of PFT abnormalities, but without significant increases over time. An improvement may be observed when good control of the iron balance is reached with optimal chelation therapy.

Adolescent↗

Iron-chelating therapy with the new oral agent ICL670 (Exjade).

Iron-chelation therapy is essential in iron-overloaded patients. The long-term efficacy of this approach has been demonstrated unequivocally with deferoxamine, which effectively controls iron concentrations, thereby limiting organ damage and preventing premature death. However, as deferoxamine is administered parenterally, poor compliance is a significant limitation to successful patient management. ICL670 (Exjade) is a highly efficient and selective oral iron chelator. The results of phase I and phase II clinical studies indicate that ICL670 is at least as effective as current standard therapy (deferoxamine), with a tolerability and safety profile suitable for chronic, once-daily administration. These encouraging results have provided the rationale for the ongoing phase III programme, and offer physicians and patients the promise of an oral, once-daily, iron-chelating agent for the prevention and management of iron overload.

Administration, Oral↗

Survival and complications in thalassemia.

The life expectancy of patients with thalassemia major has significantly increased in recent years, as reported by several groups in different countries. However, complications are still frequent and affect the patients' quality of life. In a recent study from the United Kingdom, it was found that 50% of the patients had died before age 35. At that age, 65% of the patients from an Italian long-term study were still alive. Heart disease is responsible for more than half of the deaths. The prevalence of complications in Italian patients born after 1970 includes heart failure in 7%, hypogonadism in 55%, hypothyroidism in 11%, and diabetes in 6%. Similar data were reported in patients from the United States. In the Italian study, lower ferritin levels were associated with a lower probability of experiencing heart failure and with prolonged survival. Osteoporosis and osteopenia are common and affect virtually all patients. Hepatitis C virus antibodies are present in 85% of multitransfused Italian patients, 23% of patients in the United Kingdom, 35% in the United States, 34% in France, and 21% in India. Hepatocellular carcinoma can complicate the course of hepatitis. A survey of Italian centers has identified 23 such cases in patients with a thalassemia syndrome. In conclusion, rates of survival and complication-free survival continue to improve, due to better treatment strategies. New complications are appearing in long-term survivors. Iron overload of the heart remains the main cause of morbidity and mortality.

Adolescent↗

Coagulation and splenectomy: an overview.

Venous thromboembolic events, such as pulmonary embolism, deep venous thrombosis, and portal vein thrombosis, have been observed in adult thalassemia patients, mainly in beta-thalassemia intermedia. The clinical findings are consistent with the observation of several alterations that indicate a state of activation of the hemostatic mechanisms in thalassemias. These alterations have usually been related to high platelet counts due to splenectomy and/or liver dysfunction. In a retrospective study of a large cohort of adults with thalassemia, we found a larger prevalence of venous thromboembolic events in transfusion-independent patients with thalassemia intermedia (29%) than in regularly transfused patients with thalassemia major (2%); moreover, the higher prevalence occurred particularly in splenectomized thalassemia intermedia patients. More recently, a multicenter study involving 56 tertiary referral centers in 7 countries was planned to assess the magnitude of thrombotic risk in thalassemia patients. The total number of patients who had thrombotic events was 146 (1.65%) out of 8860, with a prevalence of 0.9% in thalassemia major and 4% in thalassemia intermedia. The highest prevalence was confirmed in splenectomized patients. The observation that thrombotic events are more frequent in beta-thalassemia patients who are not receiving regular transfusions (thalassemia intermedia or thalassemia major patients in less developed countries with limited transfusion resources) or in thalassemic patients who have undergone splenectomy strongly supports the procoagulant activity of circulating damaged red blood cells.

Blood Transfusion↗

Pro-oxidant and antioxidant factors in acute intermittent porphyria: family studies.

Given the crucial role of iron and porphyrins in oxidative cellular damage in the chronic porphyrias, we undertook an extensive study in families with acute porphyrias to evaluate the possible role of similar oxidative damage in these diseases, whose natural history is often also complicated by neoplastic evolution. Four unrelated patients with acute intermittent porphyria (AIP) were studied together with 37 members of four different families. Aminolevulinic acid and porphobilinogen were measured in urine, and porphyrins in urine, plasma and stools. The activity of the congenitally deficient enzyme, porphobilinogen deaminase, and the concentrations of plasma iron, transferrin, ferritin, and various antioxidants (ascorbic acid, retinol, tocopherol, alpha- and beta-carotene, by a personal HPLC method) and the urinary and plasma metabolites of nitrous oxide were also assayed. The results showed no relationship between the observed increase of porphyrin metabolites and the presence of markers of oxidative damage or the decrease of circulating antioxidants: however, when such a decrease was registered, it depended on spontaneous or iatrogenic iron accumulation. We conclude that family screening, recommended for the identification of AIP carriers, must also include evaluation of iron stores with a view to preventing the oxidative damage and in order to forestall the neoplastic evolution of the disease.

Adolescent↗

Unreliable estimation of HbA due to the presence of Camperdown haemoglobin [beta 104 (G6) Arg --> Ser].

AIMS: To suggest the possible unreliability of HbA(1c) determination in presence of haemoglobin variants during routine metabolic evaluation. METHODS: We present a case of Camperdown haemoglobin, accidentally detected in a middle-aged Italian man during routine metabolic evaluation for newly diagnosed diabetes. The haemoglobin variant has been identified by exchange high performance liquid chromatography (CE-HPLC) (VARIANT trade mark HbA(1c) Program, Bio-Rad Laboratories, Hercules, CA, USA), and characterized at molecular level by direct sequencing. RESULTS: A 56-year-old male of Northern Italian origin, presented to our centre for a Type 2 diabetes mellitus of recent diagnosis. HbA(1c) determination was routinely determinated. The patient's chromatogram showed an inappropriate peak of 38.5% in the HbA(1c) position suggestive for the presence of abnormal haemoglobin. Further evaluation identified an abnormal haemoglobin peak even higher (49.5%) eluting at 1.34 minutes in P2-window. Molecular characterization of the mutation showed a nucleotide replacement, AGG --> AGC at codon 104, causing the amino acid replacement Arg --> Ser at position 104 (G6) that give rise to Hb Camperdown. CONCLUSIONS: Haemoglobinopathies can lead to inaccurate glycated haemoglobin level determination. In patients carrying haemoglobin variants, the different methods for determinations of glycated haemoglobin could result in different errors, showing either higher or lower values than expected.

Chromatography, High Pressure Liquid↗