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The hyperornithinemia–hyperammonemia-homocitrullinuria syndrome

Overview of attention for article published in Orphanet Journal of Rare Diseases, January 2015
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About this Attention Score

  • Above-average Attention Score compared to outputs of the same age (61st percentile)

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5 tweeters

Citations

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40 Dimensions

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92 Mendeley
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Title
The hyperornithinemia–hyperammonemia-homocitrullinuria syndrome
Published in
Orphanet Journal of Rare Diseases, January 2015
DOI 10.1186/s13023-015-0242-9
Pubmed ID
Authors

Diego Martinelli, Daria Diodato, Emanuela Ponzi, Magnus Monné, Sara Boenzi, Enrico Bertini, Giuseppe Fiermonte, Carlo Dionisi-Vici

Abstract

Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a rare autosomal recessive disorder of the urea cycle. HHH has a panethnic distribution, with a major prevalence in Canada, Italy and Japan. Acute clinical signs include intermittent episodes of vomiting, confusion or coma and hepatitis-like attacks. Alternatively, patients show a chronic course with aversion for protein rich foods, developmental delay/intellectual disability, myoclonic seizures, ataxia and pyramidal dysfunction. HHH syndrome is caused by impaired ornithine transport across the inner mitochondrial membrane due to mutations in SLC25A15 gene, which encodes for the mitochondrial ornithine carrier ORC1. The diagnosis relies on clinical signs and the peculiar metabolic triad of hyperammonemia, hyperornithinemia, and urinary excretion of homocitrulline. HHH syndrome enters in the differential diagnosis with other inherited or acquired conditions presenting with hyperammonemia. A systematic review of publications reporting patients with HHH syndrome was performed. We retrospectively evaluated the clinical, biochemical and genetic profile of 111 HHH syndrome patients, 109 reported in 61 published articles, and two unpublished cases. Lethargy and coma are frequent at disease onset, whereas pyramidal dysfunction and cognitive/behavioural abnormalities represent the most common clinical features in late-onset cases or during the disease course. Two common mutations, F188del and R179* account respectively for about 30% and 15% of patients with the HHH syndrome. Interestingly, the majority of mutations are located in residues that have side chains protruding into the internal pore of ORC1, suggesting their possible interference with substrate translocation. Acute and chronic management consists in the control of hyperammonemia with protein-restricted diet supplemented with citrulline/arginine and ammonia scavengers. Prognosis of HHH syndrome is variable, ranging from a severe course with disabling manifestations to milder variants compatible with an almost normal life. This paper provides detailed information on the clinical, metabolic and genetic profiles of all HHH syndrome patients published to date. The clinical phenotype is extremely variable and its severity does not correlate with the genotype or with recorded ammonium/ornithine plasma levels. Early intervention allows almost normal life span but the prognosis is variable, suggesting the need for a better understanding of the still unsolved pathophysiology of the disease.

Twitter Demographics

The data shown below were collected from the profiles of 5 tweeters who shared this research output. Click here to find out more about how the information was compiled.

Mendeley readers

The data shown below were compiled from readership statistics for 92 Mendeley readers of this research output. Click here to see the associated Mendeley record.

Geographical breakdown

Country Count As %
Colombia 1 1%
Unknown 91 99%

Demographic breakdown

Readers by professional status Count As %
Student > Bachelor 18 20%
Researcher 11 12%
Student > Ph. D. Student 11 12%
Student > Master 9 10%
Other 6 7%
Other 18 20%
Unknown 19 21%
Readers by discipline Count As %
Medicine and Dentistry 29 32%
Biochemistry, Genetics and Molecular Biology 9 10%
Nursing and Health Professions 7 8%
Psychology 6 7%
Agricultural and Biological Sciences 5 5%
Other 12 13%
Unknown 24 26%

Attention Score in Context

This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 21 July 2015.
All research outputs
#8,603,172
of 16,650,161 outputs
Outputs from Orphanet Journal of Rare Diseases
#806
of 1,768 outputs
Outputs of similar age
#83,991
of 220,316 outputs
Outputs of similar age from Orphanet Journal of Rare Diseases
#1
of 1 outputs
Altmetric has tracked 16,650,161 research outputs across all sources so far. This one is in the 47th percentile – i.e., 47% of other outputs scored the same or lower than it.
So far Altmetric has tracked 1,768 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 7.5. This one has gotten more attention than average, scoring higher than 53% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 220,316 tracked outputs that were published within six weeks on either side of this one in any source. This one has gotten more attention than average, scoring higher than 61% of its contemporaries.
We're also able to compare this research output to 1 others from the same source and published within six weeks on either side of this one. This one has scored higher than all of them