Aceruloplasminemia: a case report

Intracranial iron distribution and quantification in aceruloplasminemia: A case study

OBJECTIVES

Aceruloplasminemia (ACP) is a rare autosomal recessive disorder characterized by intracranial and visceral iron overload. With R2*-based imaging or quantitative susceptibility mapping (QSM), it is feasible to measure iron in the brain quantitatively, although to date this has not yet been done for patients with ACP. The aim of this study was to provide quantitative iron measurements for each affected brain region in an ACP patient with the potential to do so in all future ACP patients. This may shed light on the link between brain iron metabolism and the territories affected by ceruloplasmin function.

METHODS

We imaged a patient with ACP using a 3T magnetic resonance imaging scanner with a fifteen-channel head coil. We manually demarcated gray matter and white matter on the Strategically Acquired Gradient Echo (STAGE) images, and calculated values for susceptibility and R2* in these regions. Correlation analysis was performed between the R2* values and the susceptibility values.

RESULTS

Besides the usual territories affected in ACP, we also discovered that the mammillary bodies and the lateral habenulae had significant increases in iron, and the hippocampus was severely affected both in terms of iron content and abnormal tissue signal. We also noted that the iron in the cortical gray matter appeared to be deposited in the inner layers. Moreover, several pathways between the superior colliculus and the pulvinar thalamus, between the caudate and putamen anteriorly and between the caudate and pulvinar thalamus posteriorly were also evident. Finally, R2* correlated strongly with the QSM data (R² = 0.67, t = 6.78, p < 0.001).

CONCLUSION

QSM and R2* have proven to be sensitive and quantitative means by which to measure iron content in the brain. Our findings included several newly noted affected brain regions of iron overload and provided some new aspects of iron metabolism in ACP that may be further applicable to other pathologic conditions. Furthermore, our study may pave the way for assessing efficacy of iron chelation therapy in these patients and for other common iron related neurodegenerative disorders.

Clinical relevance of heterozygosis for aceruloplasminemia

Aceruloplasminemia is a rare form of brain iron overload of autosomal recessive inheritance that results from mutations in the CP gene, encoding the iron oxidase ceruloplasmin. Homozygous aceruloplasminemia causes progressive neurodegenerative disease, anemia, and diabetes, and is usually diagnosed late in life upon investigation of anemia, high ferritin, or movement disorders, but its heterozygous state is less characterized and believed to be silent. Here we report two heterozygotes for new mutations causing aceruloplasminemia from whom peripheral blood samples were collected for complete blood counts, iron studies, and genotyping by automated sequencing. We then performed a systematic review of preview reports of heterozygotes with data on genotype and clinical findings. Heterozygosity for aceruloplasminemia invariably causes reduced ceruloplasmin levels, and similarly to previews reports in the literature, our cases did not present with anemia. Mild hyperferritinemia was found only in two reports. Nevertheless, 5 out of 11 variants have been associated with significant neurological symptoms despite the presence of one wild-type alelle. This review contributes to better genetic counseling of heterozygotes for CP gene variants and supports that measuring ceruloplasmin levels may be useful when investigating patients with movement disorders or rare cases of unexplained high ferritin.

Pancytopenia and Myelodysplastic Changes in Aceruloplasminemia: A Case with a Novel Pathogenic Variant in the Ceruloplasmin Gene

A 72-year-old Japanese woman suffered from mild pancytopenia 3 years before her initial hospitalization. On admission, the levels of trace elements, particularly copper, and ceruloplasmin were significantly decreased in her blood serum. Abdominal lymphadenopathy and bone marrow dysplasia were detected. Hemosiderin deposition was observed in her lymph nodes and bone marrow, and magnetic resonance imaging suggested its deposition in various organs. A novel missense pathogenic variant (c.T1670G) was detected in the ceruloplasmin gene, resulting in an amino acid change (p.M557R). When copper deficiency is accompanied by cytopenia and dysplasia in a patient, it is worthwhile to consider a differential diagnosis of aceruloplasminemia.

New insights in the neurological phenotype of aceruloplasminemia in Caucasian patients

INTRODUCTION

The diagnosis aceruloplasminemia is usually made in patients with advanced neurological manifestations of the disease. In these patients prognosis is poor, disabilities are severe and patients often die young. The aim of our study was to facilitate recognition of aceruloplasminemia at a disease stage at which treatment can positively influence outcome. Currently, the neurological phenotype of aceruloplasminemia has been mainly described in Japanese patients. This 'classical' phenotype consists of cerebellar ataxia, hyperkinetic movement disorders and cognitive decline. In this study we describe the spectrum of neurological disease in Caucasian patients.

METHODS

Data on neurological presentation and follow-up were gathered from both our patients, homozygous for the G631R mutation in the CP gene, and other published Caucasian cases. Neurological features of aceruloplasminemia in Caucasian patients were compared to those summarized in Japanese patients.

RESULTS

21 Caucasian patients, both ours and the described cases, displayed a wide range of movement disorders with predominant chorea, parkinsonism and ataxia, and also tremor and dystonia. In addition to cognitive decline, nearly half of the Caucasian patients presented with psychiatric changes, including depression, anxiety and behavioral changes. In one-third of the neurologically symptomatic Caucasian patients, cognitive- or psychiatric changes were the first neurological manifestations of aceruloplasminemia.

CONCLUSIONS

Aceruloplasminemia in Caucasian patients can present with a wider range and a different order of neurological symptoms than previously described in Japanese patients. Psychiatric changes and parkinsonism can be added to the spectrum of neurological disease. Cognitive- or psychiatric changes may be the first neurological manifestations of aceruloplasminemia.

Aceruloplasminemia presents as Type 1 diabetes in non-obese adults: a detailed case series

AIM

To detect features that might lead to the early diagnosis and treatment of aceruloplasminemia, as initiation of treatment before the onset of neurological symptoms is likely to prevent neurological deterioration.

METHODS

The PubMed and OMIM databases were searched for published cases of aceruloplasminemia. Diagnostic criteria for aceruloplasminemia were undetectable or very low serum ceruloplasmin, hyperferritinemia and low transferrin saturation. Clinical, biochemical and radiological data on the presentation and follow-up of the cases were extracted and completed through e-mail contact with all authors.

RESULTS

We present an overview of 55 aceruloplasminemia cases, including three previously unreported cases. Diabetes mellitus was the first symptom related to aceruloplasminemia in 68.5% of the patients, manifesting at a median age of 38.5 years, and often accompanied by microcytic or normocytic anaemia. The combination preceded neurological symptoms in almost 90% of the neurologically symptomatic patients and was found 12.5 years before the onset of neurological symptoms.

CONCLUSIONS

There is a diagnostic window during which diabetes and anaemia are present although there is an absence of neurological symptoms. Screening for aceruloplasminemia in adult non-obese individuals presenting with antibody-negative, insulin-dependent diabetes mellitus and unexplained anaemia is recommended. The combination of ferritin and transferrin saturation provides a sensitive initial measure for aceruloplasminemia.