Common Pitfalls in the Interpretation of Endocrine Tests

Abstract

Endocrine tests are the cornerstone of diagnosing multiple diseases that primary care physicians are frequently faced with. Some of these tests can be affected by situations that affect the proper interpretation, leading to incorrect diagnoses and unnecessary treatment, such as the interference of biotin with thyroid function test, falsely elevated prolactin values in presence of macroprolactinemia or falsely normal due to the “hook effect” in macroprolactinomas. Recognizing these situations is essential for the clinician to make an adequate interpretation of these tests as well as an accurate diagnosis that guarantees the best outcomes for the patient.

Neuroendocrine Influencers and Associated Factors That Shape Jaw Movement and Growth in Temporomandibular Joint Disorder Management: A Systematic Review of Clinical and Radiographic Evidence

“…When evaluating growth hormone levels in adults, it was recommended to apply biomarkers across multiple stimuli due to the hormone’s undetectable levels between secretory spikes in healthy adults [ 29 ]. Additionally, the assessment of insulin-like growth factor 1 (IGF-1) is recommended to test for acromegaly, and plasma growth hormone releasing hormone (GHRH) testing is advised to rule out neuroendocrine tumours, while keeping in mind that these tests can be adversely affected by the oral intake of oestrogen supplements [ 29 ]. Conditions such as diabetes mellitus and liver cirrhosis may alter IGF-1 values by increasing the proteolysis of the IGF-1 binding protein 3 (IGFBP-3) [ 29 ].…”

“…In the TMJ clinics, such modalities are seldom used, and the application of adjunct clinical examination and medical imaging is preferred. This is because tumours and occlusal characteristics, such as trauma, lead to a hook effect and abnormal neuroendocrine readings [ 29 ]. Consequently, having radiomic data to support neuroendocrine profiling in the TMJ–occlusion complex is imperative, yet infrequently documented in published experiments.…”

Sepsis and Adrenal Insufficiency

“…Although the low-dose (1 µg) ACTH stimulation test may have similar diagnostic accuracy and accuracy in predicting vasopressor dependency and clinical outcomes in septic patients, it requires some preparation and offers no advantage over the high-dose ACTH test. 36 Treatment With Corticosteroids: Who, When, and How to Treat?…”

Pitfalls in the Diagnosis and Management of Hypercortisolism (Cushing Syndrome) in Humans; A Review of the Laboratory Medicine Perspective

“…Proton pump inhibitors can increase the CgA concentration significantly; therefore, they need to be stopped at least seven days prior to testing. Histamine receptor 2 antagonists require stopping at least 24 h before CgA sample collection [ 132 ]. CgA is also elevated in many other conditions, such as non-NET cancers, renal failure, and after glucocorticoid use or a meal, limiting its use as a screening tool; it is also higher in the afternoon than in the morning [ 131 , 132 , 133 ].…”

“…Histamine receptor 2 antagonists require stopping at least 24 h before CgA sample collection [ 132 ]. CgA is also elevated in many other conditions, such as non-NET cancers, renal failure, and after glucocorticoid use or a meal, limiting its use as a screening tool; it is also higher in the afternoon than in the morning [ 131 , 132 , 133 ]. Positive analytical interference has been described in the presence of haemolysis or fibrin in the specimen and due to antibody interference [ 131 ].…”