Leydig cell hypoplasia (LCH) is a rare autosomal recessive condition that interferes with normal development of male external genitalia in 46,XY individuals and is caused by inactivating mutations of the LH receptor gene. The clinical and biochemical diagnostic parameters of LCH are not always specific and may therefore show significant overlap with other causes of insufficient testicular steroid biosynthesis. We have studied a 46,XY newborn with completely female external genitalia and palpable testes. Due to an increased basal serum ratio of androstenedione/testosterone, 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD 3) deficiency was initially suspected. DNA analysis of the corresponding HSD17B3 gene, however, showed no abnormalities in the entire coding region. In contrast, direct sequencing of the LH receptor gene revealed a novel homozygous single nucleotide insertion in exon 11 (codon A589fs) producing a frame shift in the open reading frame predicting for premature termination of translation 17 amino acids downstream. From the genetic perspective, this mutation represents the first frame shift mutation in the LH receptor gene ever reported to date. From the clinical standpoint, LCH should always be considered in the differential diagnosis as steroid profiles may not be informative. Therefore, molecular genetic analysis should be warranted for androgen biosynthesis defects in all cases.
A Richter-Unruh, E Korsch, O Hiort, P M Holterhus, A P Themmen, and S A Wudy
A E Kulle, F G Riepe, J Hedderich, W G Sippell, J Schmitz, L Niermeyer, and P M Holterhus
Heterozygosity in 21-hydroxylase deficiency (21OHD) has been associated with hyperandrogenemic symptoms in children and adults. Moreover, the carrier status is mandatory for genetic counseling. We aimed at defining a hormonal parameter for carrier detection by mass spectrometry.
Eleven basal and ACTH-stimulated steroid hormones of heterozygous carriers of CYP21A2 mutations and control individuals were compared.
Hormones were determined in plasma samples by liquid chromatography tandem mass spectrometry (LC–MS/MS) in 58 carriers (35 males, 23 females, age range 6–78 years) and 44 random controls (25 males, 19 females, age range 8–58 years).
Heterozygotes could be identified best applying the 17-hydroxyprogesterone+21-deoxycortisol/cortisol×1000 ((17OHP+21S)/F×1000) equation 30 min after ACTH injection. An optimal cut-off value of 8.4 provided 89% sensitivity and specificity. Considering this data and a published frequency of heterozygotes of 1/50 to 1/61, the positive predictive value (PPV) of this cut-off is 12%. Of note, the negative predictive value (NPV) excluding heterozygosity in a given patient is 99.8%.
Considering only marginal biochemical effects anticipated from heterozygosity, the stimulated ((17OHP+21S)/F×1000) identifies and excludes heterozygotes remarkably well. Nevertheless, LC–MS/MS cannot replace genetic testing, since sensitivity and specificity did not reach 100%. However, due to the considerably high NPV of the optimal cut-off and to a specificity of even 100% applying a cut-off higher than 14.7, hormonal assessment of heterozygosity can be of significant aid in conditions with limited access to genetic testing, as in some health care systems. The ((17OHP+21S)/F×1000) equation can guide diagnostic considerations in the differential diagnosis of hyperandrogenism.
A Kulle, N Krone, P M Holterhus, G Schuler, R F Greaves, A Juul, Y B de Rijke, M F Hartmann, A Saba, O Hiort, S A Wudy, and on behalf of the EU COST Action
Disorders or differences in sex development (DSD) comprise a heterogeneous group of conditions with an atypical sex development. For optimal diagnosis, highly specialised laboratory analyses are required across European countries. Working group 3 of EU COST (European Cooperation in Science and Technology) Action BM 1303 ‘DSDnet’ ‘Harmonisation of Laboratory Assessment’ has developed recommendations on laboratory assessment for DSD regarding the use of technologies and analytes to be investigated. This position paper on steroid hormone analysis in diagnosis and treatment of DSD was compiled by a group of specialists in DSD and/or hormonal analysis, either from participating European countries or international partner countries. The topics discussed comprised analytical methods (immunoassay/mass spectrometry-based methods), matrices (urine/serum/saliva) and harmonisation of laboratory tests. The following positions were agreed upon: support of the appropriate use of immunoassay- and mass spectrometry-based methods for diagnosis and monitoring of DSD. Serum/plasma and urine are established matrices for analysis. Laboratories performing analyses for DSD need to operate within a quality framework and actively engage in harmonisation processes so that results and their interpretation are the same irrespective of the laboratory they are performed in. Participation in activities of peer comparison such as sample exchange or when available subscribing to a relevant external quality assurance program should be achieved. The ultimate aim of the guidelines is the implementation of clinical standards for diagnosis and appropriate treatment of DSD to achieve the best outcome for patients, no matter where patients are investigated or managed.
L Audí, S F Ahmed, N Krone, M Cools, K McElreavey, P M Holterhus, A Greenfield, A Bashamboo, O Hiort, S A Wudy, R McGowan, and the EU COST Action
The differential diagnosis of differences or disorders of sex development (DSD) belongs to the most complex fields in medicine. It requires a multidisciplinary team conducting a synoptic and complementary approach consisting of thorough clinical, hormonal and genetic workups. This position paper of EU COST (European Cooperation in Science and Technology) Action BM1303 ‘DSDnet’ was written by leading experts in the field and focuses on current best practice in genetic diagnosis in DSD patients. Ascertainment of the karyotpye defines one of the three major diagnostic DSD subclasses and is therefore the mandatory initial step. Subsequently, further analyses comprise molecular studies of monogenic DSD causes or analysis of copy number variations (CNV) or both. Panels of candidate genes provide rapid and reliable results. Whole exome and genome sequencing (WES and WGS) represent valuable methodological developments that are currently in the transition from basic science to clinical routine service in the field of DSD. However, in addition to covering known DSD candidate genes, WES and WGS help to identify novel genetic causes for DSD. Diagnostic interpretation must be performed with utmost caution and needs careful scientific validation in each DSD case.
T H Johannsen, A-M Andersson, S F Ahmed, Y B de Rijke, R F Greaves, M F Hartmann, O Hiort, P-M Holterhus, N P Krone, A Kulle, M L Ljubicic, G Mastorakos, J McNeilly, A M Pereira, A Saba, S A Wudy, K M Main, A Juul, and Working Group 3 of the European Cooperation in Science and Technology (COST) Action BM1303 ‘DSDnet’ and Work Package 5 ‘’ of the European Reference Network on Rare Endocrine Conditions
Differences of Sex Development (DSD) comprise a variety of congenital conditions characterized by atypical chromosomal, gonadal, or anatomical sex. Diagnosis and monitoring of treatment of patients suspected of DSD conditions include clinical examination, measurement of peptide and steroid hormones, and genetic analysis. This position paper on peptide hormone analyses in the diagnosis and control of patients with DSD was jointly prepared by specialists in the field of DSD and/or peptide hormone analysis from the European Cooperation in Science and Technology (COST) Action DSDnet (BM1303) and the European Reference Network on rare Endocrine Conditions (Endo-ERN). The goal of this position paper on peptide hormone analysis was to establish laboratory guidelines that may contribute to improve optimal diagnosis and treatment control of DSD. The essential peptide hormones used in the management of patients with DSD conditions are follicle-stimulating hormone, luteinising hormone, anti-Müllerian hormone, and Inhibin B. In this context, the following position statements have been proposed: serum and plasma are the preferred matrices; the peptide hormones can all be measured by immunoassay, while use of LC-MS/MS technology has yet to be implemented in a diagnostic setting; sex- and age-related reference values are mandatory in the evaluation of these hormones; and except for Inhibin B, external quality assurance programs are widely available.
Angela K Lucas-Herald, Jillian Bryce, Andreas Kyriakou, Marie Lindhardt Ljubicic, Wiebke Arlt, Laura Audí, Antonio Balsamo, Federico Baronio, Silvano Bertelloni, Markus Bettendorf, Antonia Brooke, Hedi L Claahsen-van der Grinten, Justin Davies, Gloria Hermann, Liat de Vries, Ieuan A Hughes, Rieko Tadokoro-Cuccaro, Feyza Darendeliler, Sukran Poyrazoglu, Mona Ellaithi, Olcay Evliyaoglu, Simona Fica, Lavinia Stejereanu, Aneta Gawlik, Evgenia Globa, Nataliya Zelinska, Tulay Guran, Ayla Güven, Sabine Hannema, Olaf Hiort, P-m Holterhus, Violeta Iotova, Vilhelm Mladenov, Vandana Jain, Rajni Sharma, Farida Jennane, Colin Johnston, Gil Guerra-Junior, Daniel Konrad, Odile Gaisl, Nils P Krone, Ruth Krone, Katherine Lachlan, Dejun Li, Corina Lichiardopol, Lidka Lisá, Renata Levoni Markosyan, Inas Mazen, Klaus Mohnike, Marek Niedziela, Anna Nordenstrom, Rodolfo A Rey, Mars Skae, Lloyd JW Tack, Jeremy W Tomlinson, Naomi Weintrob, Martine Cools, and S Faisal Ahmed
Objectives: To determine trends in clinical practice for individuals with DSD requiring gonadectomy.
Design: Retrospective cohort study.
Methods: Information regarding age at gonadectomy according to diagnosis; reported sex; time of presentation to specialist center; and location of center from cases reported to the International DSD Registry and who were over 16 years old in January 2019.
Results: Data regarding gonadectomy were available in 668 (88%) individuals from 44 centers. Of these, 248 (37%) (median age (range) 24 (17, 75) years) were male and 420 (63%) (median age (range) 26 (16, 86) years) were female. Gonadectomy was reported from 36 centers in 351/668 cases (53%). Females were more likely to undergo gonadectomy (n=311, p<0.0001). The indication for gonadectomy was reported in 268 (76%). The most common indication was mitigation of tumour risk in 172 (64%). Variations in the practice of gonadectomy were observed; of the 351 cases from 36 centers, 17 (5%) at 9 centers had undergone gonadectomy before their first presentation to the specialist center. Median age at gonadectomy of cases from high income countries and low/middle income countries (LMIC) was 13.0 yrs (0.1, 68) years and 16.5 yrs (1, 28), respectively (p<0.0001) with the likelihood of long-term retention of gonads being higher in LMIC countries.
Conclusions: The likelihood of gonadectomy depends on the underlying diagnosis, sex of rearing and the geographical setting. Clinical benchmarks, which can be studied across all forms of DSD will allow a better understanding of the variation in the practice of gonadectomy.