Lysinuric protein intolerance: an overlooked diagnosis
Abstract Background Lysinuric protein intolerance (LPI) is an autosomal recessively inherited inborn error of metabolism (IEM) caused by the defect in the dibasic cationic amino acid transporter found on the basolateral membrane of the lung, small intestine, and kidney due to mutations in the SLC7A7...
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| Format: | Article |
| Language: | English |
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SpringerOpen
2020-10-01
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| Series: | Egyptian Journal of Medical Human Genetics |
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| Online Access: | http://link.springer.com/article/10.1186/s43042-020-00084-2 |
| _version_ | 1818342116380639232 |
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| author | Asburce Olgac Idil Yenicesu Rıza Köksal Ozgul Gürsel Biberoğlu Leyla Tümer |
| author_facet | Asburce Olgac Idil Yenicesu Rıza Köksal Ozgul Gürsel Biberoğlu Leyla Tümer |
| author_sort | Asburce Olgac |
| collection | DOAJ |
| description | Abstract Background Lysinuric protein intolerance (LPI) is an autosomal recessively inherited inborn error of metabolism (IEM) caused by the defect in the dibasic cationic amino acid transporter found on the basolateral membrane of the lung, small intestine, and kidney due to mutations in the SLC7A7 gene, which encodes the y+LAT1 protein. LPI may present as an acute hyperammonemic episode or as chronic symptoms. Major clinical symptoms are feeding problems, vomiting and diarrhea, failure to thrive, hepatosplenomegaly, and cytopenia. We present a delayed diagnosis of symptomatic LPI with a homozygous mutation in the SLC7A7 gene. Case presentation A 15-year-old girl was referred to our clinic due to growth retardation and diarrhea. Physical examination showed short stature, retarded puberty, and hepatosplenomegaly. Laboratory tests showed normal complete blood count and biochemical analyses except elevated aspartate aminotransferase, triglyceride, total cholesterol, and ferritin. Peripheral blood smear and hemoglobin electrophoresis were within normal limits. Bone marrow analysis showed hemophagocytic cells. Postprandial ammonium level was found elevated. Low lysine, arginine, and ornithine and elevated glycine and alanine in plasma amino acid analysis and high amount of lysine and slightly elevated arginine and ornithine excretion in urine were detected. Molecular genetic analysis of the SLC7A7 gene showed a previously reported homozygous mutation. Low protein diet, sodium benzoate, l-carnitine, low-dose l-citrulline, and calcium replacement were initiated. The patient is now in good condition still being followed up in our department. Conclusions LPI is a metabolic disorder with multi-systemic involvement that may have severe consequences if left untreated. Initiation of early treatment is essential for the prevention of severe chronic complications. Also, confirmation of the genetic defect may provide the parents to have healthy offsprings in the future with the help of genetic counselling and preimplantation genetics. |
| first_indexed | 2024-12-13T16:09:34Z |
| format | Article |
| id | doaj.art-b4527c5402cd42c4b668f8e05aa875f9 |
| institution | Directory Open Access Journal |
| issn | 2090-2441 |
| language | English |
| last_indexed | 2024-12-13T16:09:34Z |
| publishDate | 2020-10-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Egyptian Journal of Medical Human Genetics |
| spelling | doaj.art-b4527c5402cd42c4b668f8e05aa875f92022-12-21T23:38:59ZengSpringerOpenEgyptian Journal of Medical Human Genetics2090-24412020-10-012111410.1186/s43042-020-00084-2Lysinuric protein intolerance: an overlooked diagnosisAsburce Olgac0Idil Yenicesu1Rıza Köksal Ozgul2Gürsel Biberoğlu3Leyla Tümer4Division of Pediatric Metabolism and Nutrition, Gazi University HospitalDivision of Pediatric Hematology, Gazi University HospitalDivision of Pediatric Metabolism, Hacettepe University HospitalDivision of Pediatric Metabolism and Nutrition, Gazi University HospitalDivision of Pediatric Metabolism and Nutrition, Gazi University HospitalAbstract Background Lysinuric protein intolerance (LPI) is an autosomal recessively inherited inborn error of metabolism (IEM) caused by the defect in the dibasic cationic amino acid transporter found on the basolateral membrane of the lung, small intestine, and kidney due to mutations in the SLC7A7 gene, which encodes the y+LAT1 protein. LPI may present as an acute hyperammonemic episode or as chronic symptoms. Major clinical symptoms are feeding problems, vomiting and diarrhea, failure to thrive, hepatosplenomegaly, and cytopenia. We present a delayed diagnosis of symptomatic LPI with a homozygous mutation in the SLC7A7 gene. Case presentation A 15-year-old girl was referred to our clinic due to growth retardation and diarrhea. Physical examination showed short stature, retarded puberty, and hepatosplenomegaly. Laboratory tests showed normal complete blood count and biochemical analyses except elevated aspartate aminotransferase, triglyceride, total cholesterol, and ferritin. Peripheral blood smear and hemoglobin electrophoresis were within normal limits. Bone marrow analysis showed hemophagocytic cells. Postprandial ammonium level was found elevated. Low lysine, arginine, and ornithine and elevated glycine and alanine in plasma amino acid analysis and high amount of lysine and slightly elevated arginine and ornithine excretion in urine were detected. Molecular genetic analysis of the SLC7A7 gene showed a previously reported homozygous mutation. Low protein diet, sodium benzoate, l-carnitine, low-dose l-citrulline, and calcium replacement were initiated. The patient is now in good condition still being followed up in our department. Conclusions LPI is a metabolic disorder with multi-systemic involvement that may have severe consequences if left untreated. Initiation of early treatment is essential for the prevention of severe chronic complications. Also, confirmation of the genetic defect may provide the parents to have healthy offsprings in the future with the help of genetic counselling and preimplantation genetics.http://link.springer.com/article/10.1186/s43042-020-00084-2Lysinuric protein intoleranceShort statureHemophagocytic lymphohistiocytosis |
| spellingShingle | Asburce Olgac Idil Yenicesu Rıza Köksal Ozgul Gürsel Biberoğlu Leyla Tümer Lysinuric protein intolerance: an overlooked diagnosis Egyptian Journal of Medical Human Genetics Lysinuric protein intolerance Short stature Hemophagocytic lymphohistiocytosis |
| title | Lysinuric protein intolerance: an overlooked diagnosis |
| title_full | Lysinuric protein intolerance: an overlooked diagnosis |
| title_fullStr | Lysinuric protein intolerance: an overlooked diagnosis |
| title_full_unstemmed | Lysinuric protein intolerance: an overlooked diagnosis |
| title_short | Lysinuric protein intolerance: an overlooked diagnosis |
| title_sort | lysinuric protein intolerance an overlooked diagnosis |
| topic | Lysinuric protein intolerance Short stature Hemophagocytic lymphohistiocytosis |
| url | http://link.springer.com/article/10.1186/s43042-020-00084-2 |
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