Clinical features of primary carnitine deficiency with recurrent pneumonia as the main manifestation

Abstract

Objective To investigate the clinical features of primary carnitine deficiency(PCD) with recurrent pneumonia as the main manifestation. Methods A eleven-month-old female patient hospitalized in Department of Pediatrics, the First Affiliated Hospital of Henan University of TCM in September 2015, was selected as study object. The chief complaint was Mental and motor retardation for 9 months, recurrent severe pneumonia of 5 times, cough and wheezing for 3 d . During 2- to 7-month-old, the infant had been treated in different hospitals for severe pneumonia for 5 times. After hospitalization in case collection hospital, the blood routine, blood biochemical laboratory tests, blood amino acids and acyl carnitine spectrum analysis, urine organic acid analysis and gene analysis were carried out to make a definite diagnosis of PCD.Use Gesell Developmental Scale to evaluate the development quotient(DQ). Results ①Related inspection results: this infant was characterized as growth and development retardation. The blood amino acids and acyl carnitine spectrum analysis tested at 2- month-old showed that, the free carnitine decreased significantly to 5.814 μmol/L(normal reference value is 20.000-60.000 μmol/L), and the acylcarnitine spectrum was normal. The urine organic acid analysis suggested non-ketosis second carboxyl aciduria. Free carnitine was as low as 3.73. μmol/L when 7-month-old in case collection hospital. When 11-month-old, this infant was treated in case collection hospital because of severe pneumonia and the examinations showed that: The patient has hepatic functional lesion and abnormal myocardial enzyme spectrum, and the DQ of Gesell Developmental Scale was 52.7, then the gene sequencing analysis revealed two heterozygous mutations which included a c. 1400C>G(p.S467C) and a c. 632A>G(p.Y211C)of SLC22A5 gene, ②Treatment and follow-up results: the infant was medicated with L-carnitine in the dose of 1 500 mg/d intravenous infused, meanwhile the anti-infective and supportive treatment were carried out. After disease condition improved, she was treated long-term with L-carnitine 800 mg/d orally and other support treatment. No more respiratory infections happened 4 months after release from hospital and the reexamination of liver function and myocardial enzyme spectrum were normal, and the developmental level of body build and nervous system were almost as normal child. The DQ of Gesell Developmental Scale was 63.9. Conclusions The clinical manifestations of PCD are not specific, and blood acyl carnitine spectrum analysis, urinary organic acid analysis and gene sequencing analysis are helpful for the early diagnosis of PCD. The sufficient quantities of L-carnitine medicated timely can treat it effectively and improve the prognosis. Key words: Systemic carnitine deficiency; SLC22A5 protein, human; Carnitine; Pneumonia; Respiratory insufficiency; Child