Familial hypokalemic periodic paralysis: a case induced by concurrent hyperthyroidism.
CACNA1S
Graves’ disease
Hyperthyroidism
Hypokalemia
Hypokalemic periodic paralysis
Journal
BMC nephrology
ISSN: 1471-2369
Titre abrégé: BMC Nephrol
Pays: England
ID NLM: 100967793
Informations de publication
Date de publication:
27 Sep 2024
27 Sep 2024
Historique:
received:
12
06
2024
accepted:
06
09
2024
medline:
28
9
2024
pubmed:
28
9
2024
entrez:
28
9
2024
Statut:
epublish
Résumé
Familial hypokalemic periodic paralysis (HypoPP) is an uncommon genetic disorder characterized by recurrent episodes of muscle weakness and hypokalemia, typically starting in early adulthood. The existence of hyperthyroidism in the presence of HypoPP is more strongly associated with a diagnosis of thyrotoxic periodic paralysis (TPP), with most cases occurring in Asian males with pathogenic KCNJ2 or KCNJ18 variants and without a family history of the condition. This case is novel due to the combination of familial HypoPP and hyperthyroidism induced by Graves' disease, a rare occurrence especially in non-Asian populations. A 40-year-old African American man presented with profound muscle weakness after consuming a high-salt meal. He had a significant family history of hyperthyroidism and hypokalemia. On examination, he showed profound weakness in all extremities. Laboratory tests confirmed hypokalemia and hyperthyroidism, and genetic testing identified a pathogenic variant in the CACNA1S gene (c.1583 G > A, p. R528H), with normal SCN4A, KCNJ2 and KCNJ18 sequencing. He was diagnosed with familial HypoPP and hyperthyroidism due to Graves' disease. He was started on PO methimazole 10 mg three times a day and PO acetazolamide 250 mg twice a day. He was advised to follow a low carbohydrate and low salt diet. This case highlights the importance of considering a genetic basis for HypoPP in patients with a family history of the condition, even when hyperthyroidism is present. The combination of familial HypoPP and Graves' disease is rare and emphasizes the need for careful genetic and clinical evaluation in similar cases. Management should focus on correcting hypokalemia, treating hyperthyroidism, and lifestyle modifications to prevent recurrence.
Sections du résumé
BACKGROUND
BACKGROUND
Familial hypokalemic periodic paralysis (HypoPP) is an uncommon genetic disorder characterized by recurrent episodes of muscle weakness and hypokalemia, typically starting in early adulthood. The existence of hyperthyroidism in the presence of HypoPP is more strongly associated with a diagnosis of thyrotoxic periodic paralysis (TPP), with most cases occurring in Asian males with pathogenic KCNJ2 or KCNJ18 variants and without a family history of the condition. This case is novel due to the combination of familial HypoPP and hyperthyroidism induced by Graves' disease, a rare occurrence especially in non-Asian populations.
CASE PRESENTATION
METHODS
A 40-year-old African American man presented with profound muscle weakness after consuming a high-salt meal. He had a significant family history of hyperthyroidism and hypokalemia. On examination, he showed profound weakness in all extremities. Laboratory tests confirmed hypokalemia and hyperthyroidism, and genetic testing identified a pathogenic variant in the CACNA1S gene (c.1583 G > A, p. R528H), with normal SCN4A, KCNJ2 and KCNJ18 sequencing. He was diagnosed with familial HypoPP and hyperthyroidism due to Graves' disease. He was started on PO methimazole 10 mg three times a day and PO acetazolamide 250 mg twice a day. He was advised to follow a low carbohydrate and low salt diet.
CONCLUSIONS
CONCLUSIONS
This case highlights the importance of considering a genetic basis for HypoPP in patients with a family history of the condition, even when hyperthyroidism is present. The combination of familial HypoPP and Graves' disease is rare and emphasizes the need for careful genetic and clinical evaluation in similar cases. Management should focus on correcting hypokalemia, treating hyperthyroidism, and lifestyle modifications to prevent recurrence.
Identifiants
pubmed: 39333966
doi: 10.1186/s12882-024-03749-x
pii: 10.1186/s12882-024-03749-x
doi:
Substances chimiques
CACNA1S protein, human
0
Calcium Channels, L-Type
0
Types de publication
Case Reports
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
315Informations de copyright
© 2024. The Author(s).
Références
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pubmed: 8605978
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pubmed: 26935888
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