Perinatal form hypophosphatasia caused by a novel large duplication of ALPL gene and one year follow-up under enzyme replacement therapy; a case report.

Perinatal form hypophosphatasia caused by a novel large duplication of ALPL gene and one year follow-up under enzyme replacement therapy; a case report. J Clin Res Pediatr Endocrinol. 2018 Nov 23;: Authors: Hacıhamdioğlu B, Özgürhan G, Pereira C, Tepeli E, Acar G, Cömert S Abstract Hypophosphatasia is a rare disease caused by mutations in the gene encoding tissue-nonspecific isoenzyme of alkaline phosphatase. Duplications of the ALPL gene account for fewer than 1% of the mutations causing HPP. It has been shown that asfotase alfa treatment mineralizes the skeleton and improves respiratory function and survival in severe forms of hypophosphatasia. The newborn was evaluated for respira¬tory failure and generalized hypotonia after birth. Diagnosis of HPP was based on low-serum ALP activity, high levels of substrates of tissue-nonspecific isoenzyme of alkaline phosphatase and radiologic findings. On day 21 after birth, enzyme replacement therapy using asfotase alfa (2 mg/kg three times per week, subcutaneous injection) was started. We were able to discharge our patient when he was 7 months old. His respiratory support was gradually reduced and skeletal mineralization improved during treatment. No mutation was detected in the ALPL gene by all exon sequencing, and additional analysis was done by quantitative polymerase chain reaction. As a result, a novel homozygote duplication encompassing exons 2 to 6 was detected. Early diagnosis ...
Source: JCRPE Journal of Clinical Research in Pediatric Endocrinology - Category: Endocrinology Tags: J Clin Res Pediatr Endocrinol Source Type: research