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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">KJIM</journal-id>
<journal-title-group>
<journal-title>The Korean Journal of Internal Medicine</journal-title><abbrev-journal-title>Korean J Intern Med</abbrev-journal-title></journal-title-group>
<issn pub-type="ppub">1226-3303</issn>
<issn pub-type="epub">2005-6648</issn>
<publisher>
<publisher-name>The Korean Association of Internal Medicine</publisher-name></publisher></journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3904/kjim.2017.157</article-id>
<article-id pub-id-type="publisher-id">kjim-2017-157</article-id>
<article-categories>
<subj-group>
<subject>Correspondence</subject></subj-group></article-categories>
<title-group>
<article-title>Response to comment on &#x0201c;Hypogonadotrophic hypogonadism due to a mutation in the luteinizing hormone &#x003b2;-subunit gene&#x0201d;</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Ihm</surname><given-names>Sung-Hee</given-names></name>
<xref ref-type="corresp" rid="c1-kjim-2017-157"/>
</contrib>
<aff id="af1-kjim-2017-157">
Department of Internal Medicine, Hallym University Sacred Heart Hospital, Anyang, <country>Korea</country></aff>
</contrib-group>
<author-notes>
<corresp id="c1-kjim-2017-157">Correspondence to Sung-Hee Ihm, M.D. Department of Internal Medicine, Hallym University Sacred Heart Hospital, 22 Gwanpyeong-ro 170beon-gil, Dongan-gu, Anyang 14068, Korea Tel: +82-31-380-3714 Fax: +82-31-386-2269 E-mail: <email>ihmsh@hallym.ac.kr</email></corresp>
</author-notes>
<pub-date pub-type="ppub">
<month>5</month>
<year>2017</year></pub-date>
<pub-date pub-type="epub">
<day>28</day>
<month>4</month>
<year>2017</year></pub-date>
<volume>32</volume>
<issue>3</issue>
<fpage>568</fpage>
<lpage>568</lpage>
<history>
<date date-type="received">
<day>14</day>
<month>04</month>
<year>2017</year></date>
<date date-type="accepted">
<day>26</day>
<month>04</month>
<year>2017</year></date>
</history>
<permissions>
<copyright-statement>Copyright &#x000A9; 2017 The Korean Association of Internal Medicine</copyright-statement>
<copyright-year>2017</copyright-year>
<license>
<license-p>This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (<ext-link ext-link-type="uri" xlink:href="http://creativecommons.org/licenses/by-nc/3.0/">http://creativecommons.org/licenses/by-nc/3.0/</ext-link>) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p></license></permissions>
<related-article related-article-type="letter" id="ra1-kjim-2017-157" vol="32" page="566">
<article-title>Comment on &#x0201c;Hypogonadotrophic hypogonadism due to a mutation in the luteinizing hormone &#x003b2;-subunit gene&#x0201d;</article-title>
</related-article>
</article-meta></front>
<body>
<p>We thank Dr. Valdes-Socin and colleagues for the instructive comments on our case report &#x0005b;<xref ref-type="bibr" rid="b1-kjim-2017-157">1</xref>&#x0005d; and for sharing their experience on induction of puberty and fertility in male patients with the very rare disease that is under discussion. We agree that the best initial therapeutic strategy for young males with luteinizing hormone (LH) deficiency is administration of human chorionic gonadotropin (hCG) or recombinant LH; these treatments improve spermatogenesis and maximize fertility potential &#x0005b;<xref ref-type="bibr" rid="b2-kjim-2017-157">2</xref>&#x0005d;. In patients with hypogonadotrophic hypogonadism (HH), low-dose, intramuscular injections of testosterone have been the most commonly used regimen to induce puberty in young males who do not wish to be fertile in the near future. Gonadotropin treatment is physiological in nature but can be complex (requiring frequent injections) and thus is less commonly used than testosterone treatment. A recent, prospective multicenter study on adolescents with HH found that gonadotropins successfully induced both testicular growth and spermatogenesis, irrespective of prior full-dose testosterone replacement for up to 5.7 years &#x0005b;<xref ref-type="bibr" rid="b3-kjim-2017-157">3</xref>&#x0005d;. However, some evidence suggests that prior long-term exposure to testosterone may negatively impact fertility potential of these patients. On the other hand, induction of puberty via gonadotropin injection may improve fertility potential of these patients. Although we used low-dose testosterone to induce pubertal changes in our present case (a convenient procedure complying with the wishes of the patient), we agree that the use of hCG or recombinant LH to induce puberty maximizes the testicular response and future potential fertility in patients with isolated LH deficiency.</p>
</body>
<back>
<fn-group>
<fn fn-type="conflict"><p>No potential conflict of interest relevant to this article was reported.</p></fn>
</fn-group>
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