<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0872-0169</journal-id>
<journal-title><![CDATA[Portuguese Journal of Nephrology & Hypertension]]></journal-title>
<abbrev-journal-title><![CDATA[Port J Nephrol Hypert]]></abbrev-journal-title>
<issn>0872-0169</issn>
<publisher>
<publisher-name><![CDATA[Sociedade Portuguesa de Nefrologia]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0872-01692022000300170</article-id>
<article-id pub-id-type="doi">10.32932/pjnh.2022.08.193</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[X-Linked Hypophosphatemic Rickets: A Pediatric Case Report]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Almeida]]></surname>
<given-names><![CDATA[Isabel Rodrigues Leal Moitinho de]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rodrigues]]></surname>
<given-names><![CDATA[Ana Catarina Barbosa]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Costa-Reis]]></surname>
<given-names><![CDATA[Ana Patrícia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Stone]]></surname>
<given-names><![CDATA[Maria Rosário Arriaga Câmara]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidade de Lisboa Faculdade de Medicina Clínica Universitária de Pediatria]]></institution>
<addr-line><![CDATA[Lisbon ]]></addr-line>
<country>Portugal</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Centro Hospitalar Universitário Lisboa Norte Pediatrics Department, Hospital de Santa Maria Pediatric Nephrology and Kidney Transplantation Unit]]></institution>
<addr-line><![CDATA[Lisbon ]]></addr-line>
<country>Portugal</country>
</aff>
<pub-date pub-type="pub">
<day>30</day>
<month>09</month>
<year>2022</year>
</pub-date>
<pub-date pub-type="epub">
<day>30</day>
<month>09</month>
<year>2022</year>
</pub-date>
<volume>36</volume>
<numero>3</numero>
<fpage>170</fpage>
<lpage>174</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.pt/scielo.php?script=sci_arttext&amp;pid=S0872-01692022000300170&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.pt/scielo.php?script=sci_abstract&amp;pid=S0872-01692022000300170&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.pt/scielo.php?script=sci_pdf&amp;pid=S0872-01692022000300170&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT X-linked hypophosphatemic rickets is a monogenic disease, characterized by hyperphosphaturia and hypophosphatemia. Due to its rarity and wide phenotypic variability, a diagnostic delay is common in X-linked hypophosphatemic rickets. Short stature, limb deformities, dental anomalies, craniosynostosis and chronic pain are common in this disease. Recently, burosumab, a monoclonal antibody anti-fibroblast growth factor 23, was approved for the treatment of X-linked hypophosphatemic rickets. Awareness among clinicians must be increased to improve the care of these patients. We present a clinical case of a 4-year-old girl presented with deformities of the lower limbs and an abnormal gait, associated with hyperphosphaturia and hypophosphatemia. Asymptomatic Arnold Chiari malformation was identified. No dental problems were detected. The diagnosis of X-linked hypophosphatemic rickets was confirmed by the identification of a PHEX mutation. The patient developed diarrhea, nephrocalcinosis, and hyperparathyroidism secondary to conventional therapy with phosphate supplements. Burosumab was initiated with a fast increase on serum phosphate levels and a decrease on alkaline phosphatase. With the description of this case, we highlight the clinical manifestations and complications of X-linked hypophosphatemic rickets and its treatment and we discuss new treatment strategies to improve the quality of life of these patients.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Antibodies, Monoclonal, Humanized/therapeutic use]]></kwd>
<kwd lng="en"><![CDATA[Burosumab]]></kwd>
<kwd lng="en"><![CDATA[Child]]></kwd>
<kwd lng="en"><![CDATA[Familial Hypophosphatemic Rickets/drug therapy]]></kwd>
</kwd-group>
</article-meta>
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<surname><![CDATA[Mora]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[X-Linked Hypophosphatemic Rickets: Multisystemic Disorder in Children Requiring Multidisciplinary Management]]></article-title>
<source><![CDATA[Front Endocrinol]]></source>
<year>2021</year>
<volume>12</volume>
<page-range>688309</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
