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Thorkil Christensen

Publications and source records attributed to Thorkil Christensen.

6 recordsLinked to original sources
PubMed2004

Aicardi-Goutières syndrome: neuroradiological findings after nine years of follow-up.

The main radiological features of Aicardi-Goutières syndrome include basal ganglia calcification, cerebral atrophy and white matter alterations. We present a case where progress of cerebral calcifications demonstrated on consecutive CT-scans later on was followed by a decrease. The MRI showed a progressive and significant loss of white matter and severe signal changes of the remaining myelin. The aetiology of the myelin changes and the transient worsening of the cerebral calcifications remains to be elucidated. It has previously been shown that the spinal fluid level of interferon-alpha decreases with age and we suggest that the biphasic course of the calcifications and the ventricular size as well as the clinical course shown in many patients with Aicardi-Goutières might favor a causal role of interferon-alpha in the disease leading to a transient microangiopathy.

Atrophy↗
PubMed2003

Evaluation of myocardial iron by magnetic resonance imaging during iron chelation therapy with deferrioxamine: indication of close relation between myocardial iron content and chelatable iron pool.

Evaluation of myocardial iron during iron chelation therapy is not feasible by repeated endomyocardial biopsies owing to the heterogeneity of iron distribution and the risk of complications. Recently, we described a noninvasive method based on magnetic resonance imaging. Here, the method was used for repeated estimation of the myocardial iron content during iron chelation with deferrioxamine in 14 adult nonthalassemic patients with transfusional iron overload. We investigated the repeatability of the method and the relationship between the myocardial iron estimates and iron status. The repeatability coefficient (2sD) was 2.8 micromol/g in the controls (day-to-day) and 4.0 micromol/g in the patients (within-day). Myocardial iron estimates were elevated in 10 of all 14 patients at first examination, but normalized in 6 patients after 6 to 18 months of treatment. If liver iron declined below 350 micromol/g all but one of the myocardial iron estimates were normal or nearly normal. At start (R2 = 0.69, P =.0014) and still after 6 months of iron chelation (R2 = 0.76, P =.001), the estimates were significantly and more closely related to the urinary iron excretion than to liver iron or serum ferritin levels. In conclusion, our preliminary data, which may only pertain to patients with acquired anemias, suggest the existence of a critical liver iron concentration, above which elevated myocardial iron is present, but its extent seems related to the size of the chelatable iron pool, as reflected by the urinary iron excretion. This further supports the concept of the labile iron pool as the compartment directly involved in transfusional iron toxicity.

Adult↗
PubMed2002

Relationship between hepatocellular injury and transfusional iron overload prior to and during iron chelation with desferrioxamine: a study in adult patients with acquired anemias.

The role of iron overload as cause of liver dysfunction has never been studied in detail in patients without concomitant hepatotropic infections who receive multiple transfusions. We therefore investigated the relationship between the extent of hepatocellular injury as reflected by serum levels of aminotransferases (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]) and several iron status indices in 39 anti-hepatitis C virus-negative (HCV(-)) nonthalassemic patients with transfusional iron overload owing to acquired anemias. In 12 patients, we monitored aminotransferase levels and indices of iron status during iron chelation treatment. Before treatment, elevated aminotransferase activity was seen only at liver iron concentrations more than 300 microM/g. During treatment all aminotransferase values were normal if the liver iron concentration returned below 350 microM/g. At the start of treatment, ALT (R(2) = 0.64, P =.006) and AST activity (R(2) = 0.57, P =.01) were closely related to urinary iron excretion, reflecting the size of the chelatable or the labile iron pool. During treatment, a comparable pattern was seen and the urinary iron excretion was also directly related to the liver iron concentration at concentrations above approximately 400 microM/g. All elevated ALT values were associated with a urinary iron excretion more than 15 mg/24 h. In conclusion, our data suggest the existence of a critical liver iron concentration range, above which hepatocellular injury is seen. The extent of the injury seems to be determined mainly by the size of the chelatable or labile iron pool, supporting the concept of the labile iron pool as the compartment directly involved in iron toxicity. Our findings may be helpful in establishing criteria for safety from complications of transfusional iron overload.

Adult↗