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Krombholz S, Thomas A, Delahaut P, Bidlingmaier M, Schilbach K, Miller G, Thevis M. A combined top-down and bottom-up LC-HRMS/MS method for the quantification of human growth hormone in plasma and serum. Growth Horm IGF Res 2023; 72-73:101560. [PMID: 37995539 DOI: 10.1016/j.ghir.2023.101560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 11/03/2023] [Accepted: 11/13/2023] [Indexed: 11/25/2023]
Abstract
OBJECTIVE The precise and accurate quantification of human growth hormone (GH) in plasma/ serum is crucial for the diagnosis and treatment of diseases like GH deficiency or acromegaly. However, the ligand-binding assays (LBAs) currently used for routine testing show considerable methodological variability. Here, we present a complementary, combined top-down and bottom-up LC-MS-based method to quantify (intact) GH in plasma and serum, which concurrently provides a basis for a MS-based analysis of GH in doping controls. DESIGN Extraction of GH from plasma/ serum was accomplished by protein precipitation, followed by an immunocapture step using protein A-coupled magnetic beads and a polyclonal anti-GH antibody. The intact protein was subsequently analyzed top-down on a 2D-LC-HRMS/MS system. In addition, sample extracts were digested with trypsin and analyzed for signal peptides corresponding to 'total', 22 kDa and 20 kDa GH (bottom-up). Both assays were validated according to current guidelines and compared to the GH isoform differential immunoassay used in routine doping control analysis. GH concentrations in serum samples of healthy adults, patients with acromegaly, and in samples obtained after administration of recombinant GH were analyzed as proof-of-principle. RESULTS The intact monomeric 22 kDa isoform of GH was selectively quantified in a representative working range of 0.5 to 10 ng/ml by top-down LC-HRMS/MS. Subsequent bottom-up analysis provided additional data on 'total' and 20 kDa GH. Top-down and bottom-up assay results for the 22 kDa isoform correlated well with the corresponding immunoassay results (R2 > 0.95). For a possible application of the method in an anti-doping context, the ratio between 22 kDa and 'total' GH was evaluated, indicating differences between the various donor groups, but only with limited significance. CONCLUSION The top-down and bottom-up LC-HRMS/MS method developed here presents a valuable tool for the quantification of GH in plasma/ serum complementary to established LBAs used at present in clinical measurements. Albeit the examination of the GH isoform proportions by the LC-MS method does not yet allow for the assessment of GH abuse, the obtained findings provide an important basis to enable LC-MS-based GH analysis of doping control samples in the future.
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Affiliation(s)
- Sophia Krombholz
- Center for Preventive Doping Research - Institute of Biochemistry, German Sport University Cologne, Germany
| | - Andreas Thomas
- Center for Preventive Doping Research - Institute of Biochemistry, German Sport University Cologne, Germany
| | | | - Martin Bidlingmaier
- Endocrine Research Laboratories, Department of Medicine IV, LMU University Hospital, Munich, Germany
| | - Katharina Schilbach
- Endocrine Research Laboratories, Department of Medicine IV, LMU University Hospital, Munich, Germany
| | - Geoffrey Miller
- Sports Medicine Research and Testing Laboratory, Salt Lake City, UT, USA
| | - Mario Thevis
- Center for Preventive Doping Research - Institute of Biochemistry, German Sport University Cologne, Germany; European Monitoring Center for Emerging Doping Agents (EuMoCEDA), Cologne, Bonn, Germany.
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Pontes J, Madeira M, Lima CHA, Ogino LL, de Paula Paranhos Neto F, de Mendonça LMC, Farias MLF, Kasuki L, Gadelha MR. Exon 3-deleted growth hormone receptor isoform is not related to worse bone mineral density or microarchitecture or to increased fracture risk in acromegaly. J Endocrinol Invest 2020; 43:163-171. [PMID: 31392573 DOI: 10.1007/s40618-019-01096-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 08/02/2019] [Indexed: 01/09/2023]
Abstract
PURPOSE Acromegaly is a cause of secondary osteoporosis and is associated with increased risk of vertebral fractures (VFs). The influence of exon 3-deleted isoform of growth hormone receptor (d3-GHR) on bone microarchitecture has not been studied in acromegaly. AIM The aim of this study was to analyze the associations between d3-GHR isoform and bone mineral density (BMD), bone microarchitecture, and VFs in acromegaly patients. METHODS Consecutive acromegaly patients treated at a single reference center were included. BMD was analyzed using dual-energy X-ray absorptiometry (DXA) and bone microarchitecture was analyzed by high-resolution peripheral quantitative computed tomography (HR-pQCT). The presence of moderate to severe VFs was assessed by thoracic and lumbar X-ray. GHR genotyping was analyzed by PCR, and full-length isoform of GHR (fl-GHR) was represented by a 935-bp fragment and d3-GHR by a 532-bp fragment. RESULTS Eighty-nine patients were included [56 females; median age at diagnosis: 43 years (17-78)]. Disease was uncontrolled in 63% of patients. At least one d3-GHR allele was present in 60% of patients. Frequency of active disease (p = 0.276) and hypogonadism (p = 1.000) was not different between patients with fl-GHR and those with at least one d3-GHR. There was no difference in any DXA or HR-pQCT parameters between patients with fl-GHR and those with d3-GHR. Significant VFs were observed in 14% of patients, but there was no difference in frequency between patients with fl-GHR and those with at least one d3-GHR allele (p = 0.578). CONCLUSIONS Presence of d3-GHR was not associated with worse BMD or bone microarchitecture or with higher frequency of significant VFs.
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Affiliation(s)
- J Pontes
- Neuroendocrinology Research Center, Rio de Janeiro, Brazil
| | - M Madeira
- Endocrinology Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - C H A Lima
- Neuropathology and Molecular Genetic Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil
| | - L L Ogino
- Neuropathology and Molecular Genetic Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil
| | - F de Paula Paranhos Neto
- Endocrinology Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - L M C de Mendonça
- Endocrinology Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - M L F Farias
- Endocrinology Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - L Kasuki
- Neuroendocrinology Research Center, Rio de Janeiro, Brazil
- Neuroendocrine Unit, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil
| | - M R Gadelha
- Neuroendocrinology Research Center, Rio de Janeiro, Brazil.
- Endocrinology Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
- Neuropathology and Molecular Genetic Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil.
- Neuroendocrine Unit, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil.
- Rua Professor Rodolpho Paulo Rocco, 255, 9° andar, Setor 9F, Sala de Pesquisa em Neuroendocrinologia IIha do Fundão, Rio De Janeiro, 21941-913, Brazil.
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Schilbach K, Bidlingmaier M. Laboratory investigations in the diagnosis and follow-up of GH-related disorders. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2019; 63:618-629. [PMID: 31939487 PMCID: PMC10522234 DOI: 10.20945/2359-3997000000192] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 10/12/2019] [Indexed: 11/23/2022]
Abstract
In addition to auxiological, clinical and metabolic features measurements of growth hormone (GH) and insulin-like growth factor I (IGF-I) complement our tools in diagnosis and follow-up of GH-related disorders. While comparably robust during the pre-analytical phase, measurement and interpretation of concentrations of both hormones can be challenging due to analytical issues and biological confounders. Assay methods differ in terms of antibody specificity, interference from binding proteins, reference preparations and sensitivity. GH assays have different specificity towards different GH-isoforms (e.g. 20 kDa GH, placental GH) and interference from the GH antagonist Pegvisomant. The efficacy to prevent binding protein interference is most important in IGF-I assays. Methodological differences between assays require that reference intervals and diagnostic cut-offs are assay-specific. Among biological variables, pubertal development and age are most relevant for IGF-I, making detailed reference intervals mandatory for interpretation. GH has pulsatile secretion and short half-life. Its concentration is modified by acute factors such as stress, exercise and sleep, but also by intake of oral estrogens and anthropometric factors (e.g. BMI). Other GH dependent biomarkers such as free IGF-I, IGF binding protein 3 (IGFBP 3) and acid labile subunit (ALS) have been proposed. Their concentrations largely mirror the information obtained through measurement of IGF-I, but their measurement can be helpful in particular situations. In this review, we describe the evolution of analytical methods to measure biomarkers of GH action, the impact of the methodological changes on laboratory results and the need to include biological variables in their interpretation. Arch Endocrinol Metab. 2019;63(6):618-29.
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Affiliation(s)
- Katharina Schilbach
- Medizinische Klinik und Poliklinik IVKlinikum der Universität MünchenMunichGermanyMedizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Martin Bidlingmaier
- Medizinische Klinik und Poliklinik IVKlinikum der Universität MünchenMunichGermanyMedizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
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Ribeiro de Oliveira Longo Schweizer J, Ribeiro-Oliveira A, Bidlingmaier M. Growth hormone: isoforms, clinical aspects and assays interference. Clin Diabetes Endocrinol 2018; 4:18. [PMID: 30181896 PMCID: PMC6114276 DOI: 10.1186/s40842-018-0068-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/19/2018] [Indexed: 11/11/2022] Open
Abstract
The measurement of circulating concentrations of growth hormone (GH) is an indispensable tool in the diagnosis of both GH deficiency and GH excess. GH is a heterogeneous protein composed of several molecular isoforms, but the physiological role of these different isoforms has not yet been fully understood. The 22KD GH (22 K-GH) is the main isoform in circulation, followed by 20KD GH (20 K-GH) and other rare isoforms. Studies have been performed to better understand the biological actions of the different isoforms as well as their importance in pathological conditions. Generally, the non-22 K- and 20 K-GH isoforms are secreted in parallel to 22 K-GH, and only very moderate changes in the ratio between isoforms have been described in some pituitary tumors or during exercise. Therefore, in a diagnostic approach, concentrations of 22 K-GH accurately reflect total GH secretion. On the other hand, the differential recognition of GH isoforms by different GH immunoassays used in clinical routine contributes to the known discrepancy in results from different GH assays. This makes the application of uniform decision limits problematic. Therefore, the worldwide efforts to standardize GH assays include the recommendation to use 22 K-GH specific GH assays calibrated against the pure 22 K-GH reference preparation 98/574. Adoption of this recommendation might lead to improvement in diagnosis and follow-up of pathological conditions, and facilitate the comparison of results from different laboratories.
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Affiliation(s)
| | - Antônio Ribeiro-Oliveira
- 1Endocrinology Laboratory of Federal University of Minas Gerais. Alfredo Balena, 190, Santa Efigênia, Belo Horizonte, 30130-100 Brazil
| | - Martin Bidlingmaier
- 2Endocrine Laboratory, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Ziemssenstraße 1, 80336 Munich, Germany
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Abucham J, Bronstein MD, Dias ML. MANAGEMENT OF ENDOCRINE DISEASE: Acromegaly and pregnancy: a contemporary review. Eur J Endocrinol 2017; 177:R1-R12. [PMID: 28292926 DOI: 10.1530/eje-16-1059] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 02/24/2017] [Accepted: 03/09/2017] [Indexed: 12/16/2022]
Abstract
Although fertility is frequently impaired in women with acromegaly, pregnancy is apparently becoming more common due to improvement in acromegaly treatment as well as in fertility therapy. As a result, several studies on pregnancy in patients with acromegaly have been published in recent years adding new and relevant information to the preexisting literature. Also, new GH assays with selective specificities and the knowledge of the expression of the various GH genes have allowed a better understanding of somatotrophic axis function during pregnancy. In this review, we show that pregnancy in women with acromegaly is generally safe, usually with tumoral and hormonal stability. Although the paucity of data limits evidence-based recommendations for preconception counseling and pregnancy surveillance, controlling tumor size and hormonal activity before pregnancy is highly recommended to ensure better outcomes, and surgical control should be attempted when feasible. Treatment interruption at pregnancy confirmation has also proven to be safe, as drugs are not formally allowed to be used during pregnancy. Drug exposure (somatostatin analogs) during early or whole pregnancy might increase the chance of a lower birth weight. Aggressive disease is uncommon and may urge individual decisions such as surgery or drug treatment during pregnancy or lactation.
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Affiliation(s)
- Julio Abucham
- Neuroendocrinology UnitEscola Paulista de Medicina da Universidade Federal de São Paulo, São Paulo, Brazil
| | - Marcello D Bronstein
- Division of Endocrinology and MetabolismNeuroendocrinology Unit, University of São Paulo, São Paulo, Brazil
| | - Monike L Dias
- Endocrinology UnitUniversidade Federal de Goiás, Goiânia, Brazil
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Kasuki L, Machado EDO, Ogino LL, Coelho MCA, Silva CMDS, Wildemberg LEA, Lima CHA, Gadelha MR. Experience with pegvisomant treatment in acromegaly in a single Brazilian tertiary reference center: efficacy, safety and predictors of response. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2016; 60:479-485. [PMID: 27737325 PMCID: PMC10118639 DOI: 10.1590/2359-3997000000210] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 05/18/2016] [Indexed: 11/22/2022]
Abstract
Objective To describe the safety and efficacy of pegvisomant therapy and the predictors of treatment response in acromegaly patients at a single tertiary reference center in Brazil. Materials and methods We retrospectively reviewed the clinical, hormonal and radiological data of acromegaly patients treated with pegvisomant in our center. We also evaluated the presence of the d3 isoform of the growth hormone receptor (d3GHR). Results Twenty-seven patients were included (17 women). Pegvisomant was used in combination with octreotide LAR in 20 patients (74%), in combination with cabergoline in one (4%) and as monotherapy in six (22%). IGF-I normalization was achieved in 23 patients (85%). Mild and transitory elevation of liver enzymes was observed in two patients (7.4%), tumor growth in one (3.4%) and lipodystrophy in two (7.4%). One patient stopped the drug due to headaches. The GHR isoforms were evaluated in 14 patients, and the presence of at least one d3GHR allele was observed in 43% of them, but it was not a predictor of treatment response. Only pre-treatment IGF-I level was a predictor of treatment response. Conclusion Pegvisomant treatment was highly effective and safe in our series of Brazilian patients. A better chance of disease control can be expected in those with lower pre-pegvisomant IGF-I levels.
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Affiliation(s)
- Leandro Kasuki
- Faculdade de Medicina, Centro de Pesquisa em Neuroendocrinologia, Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), Rio de Janeiro, RJ, Brasil.,Serviço de Neuroendocrinologia, Laboratório de Genética Molecular, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, RJ, Brasil.,Serviço de Endocrinologia, Hospital Federal de Bonsucesso, Rio de Janeiro, RJ, Brasil
| | - Evelyn de Oliveira Machado
- Faculdade de Medicina, Centro de Pesquisa em Neuroendocrinologia, Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), Rio de Janeiro, RJ, Brasil
| | - Liana Lumi Ogino
- Serviço de Neuroendocrinologia, Laboratório de Genética Molecular, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, RJ, Brasil
| | - Maria Caroline Alves Coelho
- Faculdade de Medicina, Centro de Pesquisa em Neuroendocrinologia, Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), Rio de Janeiro, RJ, Brasil.,Serviço de Endocrinologia, Hospital Pedro Ernesto, Rio de Janeiro, RJ, Brasil.,Serviço de Endocrinologia, Instituto Estadual de Diabetes e Endocrinologia Luiz Capriglione (IEDE), Rio de Janeiro, RJ, Brasil
| | - Cintia Marques Dos Santos Silva
- Faculdade de Medicina, Centro de Pesquisa em Neuroendocrinologia, Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), Rio de Janeiro, RJ, Brasil
| | - Luiz Eduardo Armondi Wildemberg
- Faculdade de Medicina, Centro de Pesquisa em Neuroendocrinologia, Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), Rio de Janeiro, RJ, Brasil.,Serviço de Neuroendocrinologia, Laboratório de Genética Molecular, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, RJ, Brasil
| | - Carlos Henrique Azeredo Lima
- Serviço de Neuroendocrinologia, Laboratório de Genética Molecular, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, RJ, Brasil
| | - Mônica R Gadelha
- Faculdade de Medicina, Centro de Pesquisa em Neuroendocrinologia, Serviço de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), Rio de Janeiro, RJ, Brasil.,Serviço de Neuroendocrinologia, Laboratório de Genética Molecular, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, RJ, Brasil
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de Oliveira Machado E, Lima CHA, Ogino LL, Kasuki L, Gadelha MR. Growth hormone receptor exon 3 isoforms may have no importance in the clinical setting of multiethnic Brazilian acromegaly patients. Pituitary 2016; 19:375-80. [PMID: 27001494 DOI: 10.1007/s11102-016-0715-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND Acromegaly is associated with significant morbidity and increased mortality, but has a variable severity phenotype. The presence of the exon 3-deleted isoform of the growth hormone receptor (d3-GHR) may influence the disease phenotype and treatment outcomes, including the frequency of biochemical discordance after medical treatment. AIMS The objective of this study was to analyze the influence of the d3-GHR isoform on clinical and biochemical characteristics and in the treatment outcomes of Brazilian multiethnic acromegaly patients. METHODS We retrospectively analyzed our acromegaly outpatient clinic databank and collected demographic, clinical, biochemical and treatment outcome data from those patients who agreed to participate in the study. A blood sample was collected from all patients, the DNA was extracted and the GHR isoforms were evaluated by PCR, with the full length (fl)-GHR represented by a 935-bp fragment and the d3-GHR represented by a 532-bp fragment. RESULTS A total of 121 patients were included. Fifty-six patients (46.3 %) were full-length homozygous (fl/fl), 48 (39.7 %) were heterozygous (fl/d3) and 17 (14.0 %) were d3-GHR homozygous (d3/d3). There was no difference between patients homozygous for the fl isoform and those harboring at least one d3-GHR allele in the demographic, clinical and biochemical data or in the treatment outcomes, including somatostatin receptor ligands (SRL) monotherapy, combination therapy with SRL and cabergoline and pegvisomant treatment. There was also no difference between the groups for the frequency of GH and IGF-I discordance after medical treatment. CONCLUSION GHR exon 3 genotyping appears to have no clinical significance, at least in Brazilian acromegaly patients.
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Affiliation(s)
- Evelyn de Oliveira Machado
- Neuroendocrinology Research Center/Endocrine Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rua Prof. Rodolpho Paulo Rocco, 255, 9th floor, Ilha do Fundão, Rio de Janeiro, 21941-913, Brazil
| | - Carlos Henrique Azeredo Lima
- Neuroendocrine Section and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, Brazil
| | - Liana Lumi Ogino
- Neuroendocrine Section and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, Brazil
| | - Leandro Kasuki
- Neuroendocrinology Research Center/Endocrine Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rua Prof. Rodolpho Paulo Rocco, 255, 9th floor, Ilha do Fundão, Rio de Janeiro, 21941-913, Brazil
- Neuroendocrine Section and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, Brazil
- Endocrine Section, Hospital Federal de Bonsucesso, Rio de Janeiro, Brazil
| | - Mônica R Gadelha
- Neuroendocrinology Research Center/Endocrine Section, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rua Prof. Rodolpho Paulo Rocco, 255, 9th floor, Ilha do Fundão, Rio de Janeiro, 21941-913, Brazil.
- Neuroendocrine Section and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, Brazil.
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Junnila RK, Strasburger CJ, Bidlingmaier M. Pitfalls of insulin-like growth factor-i and growth hormone assays. Endocrinol Metab Clin North Am 2015; 44:27-34. [PMID: 25732639 DOI: 10.1016/j.ecl.2014.10.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Accurate measurement of growth hormone (GH) and insulin-like growth factor-I (IGF-I) are the key to correct diagnosis of acromegaly and GH deficiency. Unfortunately, there is much variation involved when these hormones are measured at different sites and using different assay methods. There is an ongoing global effort to standardize the measurement process to obtain more comparable results in the future. This review discusses common pitfalls in the measurement of GH and IGF-I and guides laboratories in their analyses of these hormones.
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Affiliation(s)
- Riia K Junnila
- Endocrine Research Unit, Medizinische Klinik und Poliklinik IV, Klinikum der Ludwig-Maximilians-Universität (LMU), Ziemssenstr. 1, Munich 80336, Germany
| | - Christian J Strasburger
- Department of Endocrinology and Metabolic Diseases, Campus Charité Mitte, Charité Universitaetsmedizin, Charitéplatz 1, Berlin 10117, Germany
| | - Martin Bidlingmaier
- Endocrine Research Unit, Medizinische Klinik und Poliklinik IV, Klinikum der Ludwig-Maximilians-Universität (LMU), Ziemssenstr. 1, Munich 80336, Germany.
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Cozzi R, Attanasio R. Octreotide long-acting repeatable for acromegaly. Expert Rev Clin Pharmacol 2012; 5:125-43. [PMID: 22390555 DOI: 10.1586/ecp.12.4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Acromegaly remains a therapeutic challenge for the endocrinologist. Among the available therapeutic options, octreotide long-acting repeatable (Sandostatin(®) LAR(®), Novartis) plays a chief role, both as a primary therapy and as an adjuvant treatment after unsuccessful surgery. A plethora of papers and a meta-analysis have demonstrated its efficacy in: control of clinical picture; achievement of safe growth hormone and normal age-matched IGF-I levels (both factors associated with restoration of normal life expectancy) in 60-70% of patients; control of tumor volume (with real shrinkage in over half of cases); and halt or reversal of most acromegaly-associated comorbidities. Treatment is well tolerated in most patients and can be safely prolonged for many years if required.
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Affiliation(s)
- Renato Cozzi
- Division of Endocrinology, Ospedale Niguarda, Via Canonica 81, I-20154 Milan, Italy.
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