Editing Leydig cell (section)

==Clinical significance==
[[Image:Leydig cell tumour3.jpg|thumb|right|100px|[[Micrograph]] of a [[Leydig cell tumour]]. [[H&E stain]].]]
Leydig cells may grow uncontrollably and form a [[Leydig cell tumour]]. These may be hormonally active, i.e. secrete testosterone. The function of [[Reinke crystals]] is unknown, but they appear in the case of Leydig cell tumours.<ref name="Partin"/> They are found in less than half of all Leydig cell tumors, but when present, they may serve to confirm the diagnosis of a Leydig cell tumor.<ref name="Agha">{{cite journal |vauthors=Al-Agha O, Axiotis C |title=An in-depth look at Leydig cell tumor of the testis |journal=Arch Pathol Lab Med |volume=131 |issue=2 |pages=311–7 |year=2007 |pmid=17284120 |doi=10.5858/2007-131-311-AILALC}}</ref><ref name="Reinke1">{{cite web | author= Ramnani, Dharam M | title=Leydig Cell Tumor : Reinke's Crystalloids | url=http://www.webpathology.com/image.asp?case=38&n=3 | date=2010-06-11 | access-date=2011-11-06}}</ref> No other interstitial cell within the testes has a nucleus or cytoplasm with these characteristics, making identification relatively easy.

While any age is susceptible to a Leydig cell tumour, Leydig cell tumours are more common in people aged 5 to 10 and 30 to 35.<ref name="Jameson">{{Cite book|last1=Jameson|first1= J. Larry|last2=De Groot|first2=Leslie J.|title=Endocrinology: Adult and Pediatric|date=2015|publisher=Elsevier Health Sciences|isbn=978-0-32-332195-2|page=2365|url=https://books.google.com/books?id=xmLeBgAAQBAJ&pg=PA2365}}</ref> A Leydig cell tumour in a child usually causes [[precocious puberty]].<ref name="Jameson"/> About 10% of boys with the tumour have [[gynecomastia]].<ref name="Jameson"/> Although a Leydig cell tumour is always [[benign tumor|benign]] in children, it is [[malignant]] in 10% to 15% of adults.<ref name="Jameson"/> It is the most common [[testicular cancer]] of non-[[germ cell]] origin.<ref name="Henningsen">{{Cite book|last1=Henningsen|first1=Charlotte|last2=Kuntz|first2=Kathryn|last3=Youngs|first3=Diane|title=Clinical Guide to Sonography: Exercises for Critical Thinking|date=2013|publisher=Elsevier Health Sciences|isbn=978-0-32-309164-0|page=350|url=https://books.google.com/books?id=HU7orJzrZNwC&pg=PA350}}</ref>

[[Sonography]] may be used to identify [[cystic]] areas, but it is unable to tell benign tumours apart from malignant tumours.<ref name="Henningsen"/>

[[adrenoleukodystrophy|Adrenomyeloneuropathy]] is another example of a disease affecting the Leydig cell.<ref name="Chovel-Sella">{{Cite book|last1=Chovel-Sella|first1=Alum|last2=Halper|first2=Alyssa|title=Endocrine Conditions in Pediatrics: A Practical Guide|chapter=Adrenal Insufficiency|date=2020|publisher=Springer Nature|isbn=978-3-03-052215-5|page=286|chapter-url=https://books.google.com/books?id=YXT_DwAAQBAJ&pg=PA286}}</ref> In this case, a person's testosterone may fall despite higher-than-normal levels of LH and [[follicle-stimulating hormone]] (FSH).