18º Congresso Brasileiro de Neurologia Infantil

Dados do Trabalho



Apresentação do caso

A 2-month-old infant, born by c-section, 38 weeks, was diagnosed intrauterine with congenital clubfoot. He presented with episodes of drowsiness since birth and had an episode of bronchoaspiration, where he was referred to a referral hospital. He was diagnosed with grade I pulmonary hypertension, and remained on mechanical ventilation for 13 days and non-invasive ventilation for 9 days. After mechanical ventilation was discontinued, irritability, continued somnolence, and myoclonic spasms were observed. He was again hospitalized, where oral automatisms were observed and he was introduced to phenobarbital. A treatable disease panel was taken, which showed intragenic deletion of exons 1 to 2 in heterozygosity in the GLDC gene.

He was introduced to sodium benzoate and L carnitine at two months of age and was referred to this service for follow-up with nutrology. In his first visit, difficult to control seizures were evidenced, and he was admitted for evaluation and management with neurology. On physical exam, he presented significant irritability, axial hypotonia with appendicular hypertonia, hyperreflexia, oral automatisms associated with upward ocular version events, and myoclonias. He is currently taking Levetiracetam, Clonazepam, Phenobarbital, and Topiramate, with an improvement in the seizure pattern, but without control.


Nonketotic hyperglycinemia is characterized by an inborn error of metabolism that manifests itself by seizures that are difficult to control due to the lack of an enzyme that catalyzes the conversion of glycine into carbon dioxide and ammonia in the liver and brain.

The mutations occur frequently in the GLDC and AMT genes and are responsible for severe neurological symptoms such as intractable epilepsy, delayed neuropsychomotor development, and hypotonia. This patient did not need a glycine test to confirm the disease because he had already undergone a genetic test, which confirmed the diagnosis.

The prognosis of the disease is poor, and the use of sodium benzoate has a positive effect on the treatment by reducing the levels of glycine in the blood. The use of L carnitine occurs because of the frequent deficiency of it, caused by the therapy with sodium benzoate.

Comentários finais

Thus, greater investment is needed in formulations accessible to the population for the treatment of a disease that is difficult to control and manage, as well as multidisciplinary monitoring of patients to prevent complications related to the disease.

Referências (se houver)

1 – Nowak et al - Nonketotic Hyperglycinemia: Insight into Current Therapies - J. Clin. Med. 2022, 11, 3027. https://doi.org/10.3390/jcm11113027
2 – Tedrus et al – crises epilépticas e hiperglicinemia não cetótica – Revista de ciências médicas PUCCAMP Campinas, 4 (2): 62-65 – maio/agosto 1995
3 – Iqbal M, Prasad M, Mordekar SR. Nonketotic hyperglycinemia case series. J Pediatr Neurosci. 2015 Oct-Dec;10(4):355-8. doi: 10.4103/1817-1745.174445. PMID: 26962342; PMCID: PMC4770648.
4 - Tada K, Narisawa K, Yoshida T, Konno T, Yokoyama Y. Hyperglycinemia: a defect in glycine cleavage reaction. Tohoku J Exp Med. 1969 Jul;98(3):289-96. doi: 10.1620/tjem.98.289. PMID: 5307488.
5 - Farris J, Calhoun B, Alam MS, Lee S, Haldar K (2020) Large scale analyses of genotype-phenotype relationships of glycine decarboxylase mutations and neurological disease severity. PLOS Computational Biology 16(5): e1007871. https://doi.org/10.1371/journal.pcbi.1007871

Palavras Chave

hiperglicinemia, glicina, relato de caso

Fonte de Fomento (se houver)

Declaração de conflito de interesses de TODOS os autores

Não há conflito de interesse


Erros inatos do metabolismo


UFRJ - Rio de Janeiro - Brasil


Sarah Falcão Brasileiro Henriques, Maria Mariana Muniz Jorge de Melo, Jéssica Kayene Souza Ferreira, Ana Paula Bastos Nogueira De Luca, Maria Lina Giacomino de Almeida Passos e Azevedo, Fernanda dos Santos Ribeiro, Amanda Regina Farias Teixeira, Patrícia Selestrini, Flávia Nardes dos Santos