Urinary 5-hydroxyindoleacetic Acid Research Articles

7204 An Unexpected Cause of Ga-68 Dotatate PET/CT Somatostatin Receptor Avidity in a Pediatric Patient with Hereditary Paraganglioma-Pheochromocytoma Syndrome due to an SDHA Mutation

Abstract Disclosure: K. Leopold: None. S. Polites: None. L. Binkovitz: None. L. Casas: None. A.N. Lteif: None. Title: An Unexpected Cause of Ga-68 Dotatate PET/CT Somatostatin Receptor Avidity in a Pediatric Patient with Hereditary Paraganglioma-Pheochromocytoma Syndrome due to an SDHA Mutation. Introduction: Individuals with Succinate Dehydrogenase (SDHx) gene mutations have an increased risk of paragangliomas and pheochromocytomas beginning in childhood.Clinical Case: A 9 year old male with Cornelia de Lange syndrome and a paternally inherited SDHA pathogenic gene variant (c1534C>T) presented with worsening migraine headaches and skin pallor with activity. 24 hour urine fractionated metanephrines were mildly elevated, with metanephrine 122 mcg/24h (29-92 mcg/24 h), normetanephrine 187 mcg/24 h (34-169 mcg/24 h), and total metanephrine 309 mcg/24 h (47-223 mcg/24 h). Ga-68 DOTATATE PET/CT showed a focus of moderately increased radiotracer activity in the anterior aspect of the distal gastric antrum with a max SUV 8.2 corresponding to a 9x7 mm nodule on CT in the same area, suggestive of underlying somatostatin receptor positive lesion such as a paraganglioma. MRI with contrast completed to further characterize the lesion showed no visible mass corresponding to the focal area of radiotracer uptake on DOTATATE PET/CT. Repeat 24 h urine metanephrines continued to show mild elevation of metanephrine (138 mcg/24h), normetanephrine (200 mcg/24h), and total metanephrines (338 mcg/24h). 24 hour urine catecholamines, 5-Hydroxyindoleacetic acid, and homovanillic acid were normal. An upper endoscopic ultrasound was completed which confirmed the presence of a lesion near the stomach but not arising from the stomach wall and not consistent with a gastrointestinal stromal tumor. CT enterography with IV contrast showed a 6x6 mm enhancing mass within the distal right lateral gastric wall. Due to ongoing symptoms, mild elevations in urine fractionated metanephrines, and a clear mass on US and CT, the patient underwent laparoscopic abdominal exploration where a 14x14x13 mm mass with surrounding gastric and duodenal serosa was excised with primary closure of the bowel. Pathology showed ectopic pancreatic tissue in the wall of the small bowel and stomach. Repeat Ga-68 DOTATATE PET/CT 5 months following surgery showed resolution of the distal gastric somatostatin receptor avidity. Clinical Lesson: This is the first case of ectopic pancreatic tissue mimicking a paraganglioma in a pediatric patient with hereditary paraganglioma-pheochromocytoma syndrome. False positive imaging should be considered in patients with SDHx mutations when the uptake is atypical in location and when the elevation in urine metanephrines is mild. Presentation: 6/3/2024

Urticaria Pigmentosa – A Case Report with a Review of the Literature

Mastocytosis encompasses a rare group of diseases characterized by the accumulation of mast cells, primarily in the skin or internal organs. In the 2016 revised WHO classification, mastocytosis is divided into cutaneous mastocytosis (CM), systemic mastocytosis (CM), and localized mast cell tumor. Cutaneous mastocytosis (CM) includes maculo-papular CM/urticaria pigmentosa (UP), diffuse CM and cutaneous mastocytoma. Urticaria pigmentosa is the most common skin variant. It presents with erythematous brownish macules or papules, often accompanied by pruritus. A case of a 48-year-old woman with disseminated, mildly pruritic, sharply demarcated, livid-brownish macules on the skin of the trunk and extremities is presented. A positive Darier symptom was established. Laboratory tests revealed granulocytosis (73%) and lymphocytosis (19.8%). Serum tryptase and 24-hour urine 5-hydroxyindoleacetic acid were not elevated. The diagnosis of urticaria pigmentosa was confirmed by the histopathological examination revealing perivascular infiltrates of mast cells, mainly in the deep dermis. Screening performed did not detect systemic involvement. Symptomatic treatment with H1 and H2 blockers and topical corticosteroid was carried out. Avoidance of triggers is recommended. The patient's condition has improved. Both a historical review of mastocytosis and a revised classification, as well as the epidemiology, etiology with triggering factors, clinical presentation, laboratory investigations, and management of urticaria pigmentosa are presented.

Urine 5-Hydroxyindoleacetic Acid Negatively Correlates with Migraine Occurrence and Characteristics in the Interictal Phase of Episodic Migraine.

Although migraine belongs to the main causes of disability worldwide, the mechanisms of its pathogenesis are poorly known. As migraine diagnosis is based on the subjective assessment of symptoms, there is a need to establish objective auxiliary markers to support clinical diagnosis. Tryptophan (TRP) metabolism has been associated with the pathogenesis of neurological and psychiatric disorders. In the present work, we investigated an association between migraine and the urine concentration of TRP and its metabolites 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), kynurenic acid (KYNA) and quinolinic acid (QA) in 21 low-frequency episodic migraine patients and 32 controls. We chose the interictal phase as the episodic migraine patients were recruited from the outpatient clinic and had monthly migraine days as low as 1-2 in many cases. Migraine patients displayed lower urinary levels of 5-HIAA (p < 0.01) and KYNA (p < 0.05), but KYN and QA were enhanced, as compared with the controls (p < 0.05 and 0.001, respectively). Consequently, the patients were characterized by different values of the 5-HIAA/TRP, KYN/TRP, KYNA/KYN, and KYNA/QA ratios (p < 0.001 for all). Furthermore, urinary concentration of 5-HIAA was negatively correlated with Migraine Disability Assessment score and monthly migraine and monthly headache days. There was a negative correlation between Patient Health Questionnaire 9 scores assessing depression. In conclusion, the urinary 5-HIAA level may be further explored to assess its suitability as an easy-to-determine marker of migraine.

Optimal follow-up with somatostatin receptor PET/CT imaging in patients with small intestinal neuroendocrine tumours.

Somatostatin receptor positron emission tomography with computerised tomography imaging (SRI) has a high sensitivity for the detection of small intestinal neuroendocrine tumors (siNET), which makes it ideal for follow-up. The aim of the present study was to investigate whether follow-up with SRI in patients with siNET led to any change in the treatment of the patient and if patient and/or tumour factors were associated with such change. Adults with siNET who had undergone at least two SRI scans between 2013 and 2021 were identified. Data on age, sex, comorbidities, tumour stage, grade, and most recent levels of serum Chromogranin A (CgA) and 24-h urine 5-hydroxyindoleacetic acid (5-HIAA) before each SRI scan were obtained. The major change was defined as new treatment previously not received or discontinuation of ongoing treatment. Univariate and multivariate mixed models logistic regression on variables with a presumed biological relationship with major change and with backwards stepwise exclusion of variables with p > .1 was performed. A total of 164 patients with siNET diagnosis had undergone 570 SRI scans. The median follow-up was 3.1 years. Only 82 of 570, 14%, of SRI scans led to a major change in treatment. Female sex, age below 75 years, elevated or missing CgA, elevated or missing urine 5-HIAA, progress on last SRI scan and distant extrahepatic disease were all independently associated with increased odds ratios for major change after follow-up with SRI. A small proportion of SRI scans (14%) led to a major change in treatment. Six independent risk factors with increased odds of major change, all available before each SRI scan, were identified. While validation of these risk factors is needed in a separate cohort, these findings could help clinicians individualise follow-up for siNET patients in the future.

Impact of grade on workup of rectal neuroendocrine tumors: a retrospective cohort study

BackgroundRectal neuroendocrine tumors (RNETs) are often discovered on screening colonoscopy. Indications for staging and definitive resection are inconsistent in current guidelines. We evaluated the role of grade in guiding staging and procedural decision-making.MethodsPatients with biopsy confirmed RNETs between 2004 and 2015 were reviewed. Baseline characteristics, staging investigations (biochemical and imaging), and endoscopic/surgical treatment were recorded. Associations between grade, preoperative staging, interventions, and survival were determined using Fisher-Freeman-Halton Exact, log-rank, and Kaplan-Meier analysis.ResultsAmongst 139 patients with RNETs, 9% were aged ≥ 75 years and 44% female. Tumor grade was: 73% grade 1 (G1), 18%, grade 2 (G2) and 9% grade 3 (G3). Staging investigations were performed in 52% of patients. All serum chromogranin A and 97% of 24-hour urine 5-hydroxyindoleacetic acid tests were normal. The large majority of staging computed tomography (CT) scans were negative (76%) with subgroup analysis showing no G1 patients with CT identified distant disease compared with 38% of G2 and 50% of G3 patients (p < 0.001). G1 patients were more likely to achieve R0/R1 resections compared to G2 (95% vs. 50%, p < 0.001) and G1 patients had significantly better 5-year overall survival (G1: 98%, G2: 67%, G3: 10%, p < 0.001).ConclusionTumor grade is important in preoperative workup and surgical decision-making. Biochemical staging may be omitted but staging CT should be considered for patients with grade ≥ 2 lesions. Anatomic resections should be considered for patients with grade 2 disease.

Subclinical Echocardiographic Parameters and Biomarker Approach to Characterize the Pathophysiology of Carcinoid Syndrome

Introduction: Carcinoid heart disease is a rare cause of right-sided valvular dysfunction, an important complication in patients with carcinoid syndrome. Objectives: We aim to present our own experience regarding early myocardial dysfunction in patients with carcinoid syndrome. Methods: 64 patients (35-90 year old, 62,5% female, 37,5% male patients) with carcinoid syndrome were evaluated between October 2017 and June 2021. All patients underwent two-dimensional echocardiography with additional tissue Doppler and speckle-tracking techniques. For all patients there were measured urinary level of 5- hydroxyindolacetic acid, serotonin and NT-proBNP values. Results: The following echocardiographic features: global longitudinal strain of both ventricles, mean systolic velocity of the left ventricle, systolic velocity of the free wall of right ventricle, correlated with high values of specific biomarkers: serotonin, and urinary 5-hydroxyindolacetic acid, and also with the presence of hepatic metastases and poorly differentiated tumors. Discussion: In this study we identified several patients with early myocardial dysfunction due to carcinoid syndrome, representing a predictive model of poor prognosis, requiring further investigations. Conclusion: Echocardiographic assessment based on the measurement of systolic velocities, as well as the global longitudinal strain of both ventricles, together with specific biomarkers may contribute to better recognition of carcinoid heart disease in clinical practice, but this needs validation through further studies enrolling larger number of patients.

Urinary 5-Hydroxyindolacetic Acid Measurements in Patients with Neuroendocrine Tumor-Related Carcinoid Syndrome: State of the Art.

Carcinoid syndrome (CS), mostly associated with small intestinal neuroendocrine tumors (SI-NETs) or lung-related NETs, is characterized by symptoms related to hormonal secretion and long-term complications, including carcinoid heart disease (CHD), which is potentially life-threatening. In the early stages of the disease, symptoms are non-specific, which leads to delayed diagnoses. The availability of reliable tumor markers is crucial for a prompt diagnosis and proper management. This review summarizes available evidence on the role of 24 h urinary 5-hydroxyindolacetic acid (24u5HIAA), which is the urinary breakdown metabolite of serotonin, in the diagnosis/follow-up of NET-related CS, with a focus on its potential prognostic role, while eventually attempting to suggest a timeline for its measurement during the follow-up of NET patients. The use of 24u5HIAA is an established biomarker for the diagnosis of NETs with CS since it shows a sensibility and specificity of 100% and 85-90%, respectively. The downside of 24u5-HIAA is represented by the need for 24 h urine collection and the risk of confounding factors (foods and medication), which might lead to false positive/negative results. Moreover, 24u5HIAA is useful in the follow-up of NETs with CS since a shorter double time correlates to a higher risk of disease progression/disease-specific mortality. Furthermore, an elevation in 24u5-HIAA is correlated with a dismal prognosis because it is associated with an increased likelihood of CHD development and disease progression/mortality. Other potentially interesting biochemical markers have been proposed, including plasmatic 5HIAA, although further standardization and prospective studies are required to define their role in the management of NETs. Meanwhile, 24u5HIAA remains the most accurate CS biomarker.

Analytical method for urinary homovanillic acid and 5-hydroxyindoleacetic acid levels using HPLC with electrochemical detection applied to evaluate children environmentally exposed to manganese.

Homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) are the urinary metabolites of dopamine (DA) and serotonin (5-HA), respectively. We aimed to develop an extraction method for the determination of HVA and 5-HIAA, using strong anionic exchange cartridges combined with HPLC with electrochemical detection, and apply it to measure the levels of HVA and 5-HIAA in children living near a ferro-manganese alloy plant in Simões Filho, Brazil. The validated method showed good selectivity, sensitivity, precision, and accuracy. The limits of detection (LOD) were 4 and 8 μmol/L for 5-HIAA and HVA, respectively, in urine. Recoveries ranged from 85.8 to 94%. The coefficients of determination (R2 ) of the calibration curves were greater than 0.99. Spot urine samples of 30 exposed children and 20 nonexposed ones were processed accordingly. The metabolite levels in exposed and reference children were within the physiological ranges. The medians (range) for 5-HIAA and HVA of the exposed ones were 36.4 μmol/L (18.4-58.0) and 32.9 μmol/L (<LOD-91.9), respectively. There was no significant difference between the values presented by children in the reference group: 25.7 μmol/L (19.9-81.4) and 35.2 μmol/L (<LOD-67.6) for 5-HIAA and HVA, respectively. These results suggest that the quantification of the urinary metabolites possibly does not reflect the interference of manganese in the metabolism of DA and 5-HA in the central nervous system.

P-136 Increased healthcare costs due to diagnostic imaging services following false elevation of plasma chromogranin A and 24-hour urinary 5-hydroxyindoleacetic acid: A quality improvement project

P-136 Increased healthcare costs due to diagnostic imaging services following false elevation of plasma chromogranin A and 24-hour urinary 5-hydroxyindoleacetic acid: A quality improvement project

Carcinoid Heart Disease Management: A Multi-Disciplinary Collaboration.

Carcinoid heart disease (CaHD) is an important complication among patients with metastatic neuroendocrine tumors and carcinoid syndrome (CS). CS patients (25%-65%) eventually develop CaHD; these patients face a significantly increased risk of morbidity and mortality. Guidance papers (eg, clinical practice guidelines, consensus guidelines, and expert statements) have been established by major organizations across the disciplines of cardiology and oncology; however, these recommendations are not routinely implemented. The aim of this article is to encourage the integration of current recommendations from national societies into clinical practice. Early screening upon recognition of CS and prior to the development of CaHD symptoms is paramount, as no existing therapies are approved to reverse the fibrotic damage to the heart once it occurs. Valvular replacement is the only definitive treatment for CaHD once it has developed. When patients are noted to have urinary 5-hydroxyindoleacetic acid (5-HIAA) levels ≥300 µmol/24 h and/or serum N-terminal pro B-type natriuretic peptide (NT-proBNP) levels >260 pg/mL, echocardiography is recommended. Systemic approaches to control tumor growth and hormonal secretion include somatostatin analogs (SSAs), followed by options including peptide receptor radiotherapy (PRRT), everolimus and liver embolization. Telotristat is the primary choice for control of diarrhea refractory to SSA. Diuretics are the mainstay of heart failure symptom management for patients who develop CaHD. Considerations for future research are discussed, including the ongoing TELEHEART (TELotristat Ethyl in a HEART biomarker study) trial involving telotristat and not yet activated CHARRT (Carcinoid Heart disease And peptide Receptor Radiotargetted Therapy) study involving PRRT with lutetium 177 (177Lu) dotatate.

The role of serotonin inhibition within the treatment of carcinoid syndrome.

Carcinoid syndrome is the most frequent hormonal complication associated with neuroendocrine neoplasms. It was first reported in 1954, and the classical symptoms are diarrhoea, flushing and abdominal pain. It is caused by the secretion of several vasoactive substances, the most prominent being serotonin, which play a pathophysiological role in the clinical symptoms which characterise carcinoid syndrome. Therefore, the focus of carcinoid syndrome treatment is to reduce serotonin production and hence improve the patient's quality of life. There are a variety of management options for carcinoid syndrome including medical, surgical and loco-regional interventional radiological procedures. The most widely used are somatostatin analogues with three clinically approved drugs: lanreotide and octreotide (first-generation) and pasireotide (second-generation). Both everolimus and interferon used in combination with octreotide have shown significant reduction in urinary 5-hydroxyindoleacetic acid compared to octreotide alone. Telotristat ethyl has been increasingly utilised for patients with symptoms despite taking somatostatin analogues. It has also been shown to have a significant improvement in bowel movement frequency which was associated with a significant improvement in quality of life. Peptide receptor radionuclide therapy has proven symptomatic improvement in patients with uncontrolled symptoms. Chemotherapy is primarily reserved for patients with high proliferation tumours, with limited research on the efficacy in reducing symptoms. Surgical resection remains the optimal treatment due to being the only one that can achieve a cure. Liver-directed therapies are considered in patients where curative resection is not possible. There are therefore numerous different therapies. This paper describes the pathophysiology and therapy of carcinoid syndrome.

Acute effects of fresh versus dried Hayward green kiwifruit on sleep quality, mood, and sleep-related urinary metabolites in healthy young men with good and poor sleep quality.

Daily kiwifruit (KF) consumption has been associated with improved sleep quality, but underlying physiological mechanisms are unknown. This study examined acute effects of fresh and dried green KF, compared with a water control, on sleep quality, mood, and urinary serotonin and melatonin metabolite concentrations. 24 men (age: 29 ± 1 years, body mass index: 24 ± 1 kg/m2) with poor (n = 12) or good (n = 12) sleep quality participated in a randomized, single-blind crossover study. One of three treatments was consumed with a standardized evening meal; (1) the flesh of two fresh green KF, (2) dried green KF powder (including skin; equivalent to dry matter of two fresh KF) mixed with water, or (3) a water control, in their own home. Subjective and objective sleep quality, mood, waking urinary 5-hydroxyindoleacetic acid (5-HIAA), 6-sulfatoxymelatonin (aMT6s), vitamin C and B-vitamin concentrations were determined. Regardless of sleep quality group, compared to control, morning sleepiness, alertness upon awakening, and vigor were improved (p < 0.05) after dried KF consumption. Compared to control, both fresh and dried KF treatments tended (p < 0.1) toward improved esteem and total mood disturbance. Both KF treatments increased (fresh +1.56 ± 0.4 ng/g, p = 0.001; dried: +1.30 ± 0.4 ng/g, p = 0.004) urinary concentration of the serotonin metabolite 5-HIAA compared to the control (4.32 ± 0.4 ng/g). In poor sleepers, ease of awakening improved by 24% after dried KF consumption (p = 0.005) and tended to improve by 13% after fresh KF intake (p = 0.052) compared to the control. Good sleepers tended toward 9% improved ratings of getting to sleep with fresh KF (p = 0.053) compared to the control. Poor sleepers had lower amounts of some B-vitamins compared to good sleepers (p < 0.05). Consumption of dried or fresh KF with a standard evening meal, was associated with improved aspects of sleep quality and mood, possibly mediated through changes in serotonin metabolism. [www.anzctr.org.au], identifier [ACTRN12621000046808]. Graphical Abstract.

P373 An Unusual Occurrence of Right-sided Colonic Neuroendocrine Carcinoma in Ulcerative Colitis – A case report

Abstract Background It's estimated that inflammatory bowel disease (IBD) accounts for 1-2% of all colorectal cancer (CRC) cases. However, the mere presence of IBD increases the risk by 2 folds compared with the general population. It's been established that the most prevalent epithelial colonic malignancy linked to IBD is adenocarcinoma. Neuroendocrine neoplasms arising in the large intestines are extremely rare (rate &amp;lt;1%), even less common in association with IBD.(1) Herein, we report a 49 years-old male with a longstanding history of ulcerative pancolitis, who was found to have a metastatic right-sided colorectal neuroendocrine carcinoma (NEC). Methods Case Presentation A 49-years-old male patient, with a 13-years history of ulcerative pancolitis underwent a colonoscopy. It revealed a large ulcerated mass extending from the ileocecal valve into the proximal ascending colon highly suspicious for malignancy. Biopsy showed a large cell poorly differentiated NEC in the ascending colon. Tumor cells were positive for Synaptophysin and cytokeratin AE1/3, and a high Ki67. Serum Chromogranin A (CgA) and urine 5-hydroxyindoleacetic acid were high. Imaging was evident for a short segment circumferential wall thickening at the ascending colon and hepatic metastasis. The patient was planned to receive chemotherapy, but died before treatment. Results Discussion Risk of CRC increments linearly approximately 7 years following diagnosis of IBD. After 30 years of colitis, the incidence is estimated to be around 18%. NECs in particular are not frequently encountered in association with IBD, much less right-sided.(1) Colonic NECs are usually aggressive with a Ki67 typically greater than 20%, often present with metastasis with absence of a characteristic hormonal secretion picture.(2, 3) The incidence of NECs in association with Ulcerative Colitis (UC) is twice more frequent in males, with a mean age of 49.36, and development after a median of 15 years of UC first diagnosis. Majority of NECs were found in the left side of the colon, in the contrary to our patient. Prognosis was dismal in most cases, as most demonstrated a higher malignant potential compared to adenocarcinomas.(3) Early diagnosis of gastrointestinal NECs poses a challenge since it lacks a specific clinical presentation. Serum CgA level correlates with the tumor burden and overall survival. Additionally, studies demonstrating the role of endoscopic surveillance in colonic NECs early detection is scarce.(1,4) Conclusion Thorough understanding of the condition and its risk factors is crucial for a timely diagnosis, which maximizes the likelihood of a favorable prognosis. By reporting this case, we emphasize the importance of considering NEC as a differential diagnosis of CRC in IBD, particularly in UC patients.

Standardisation of Dietary and Medication Restrictions for Urine 5-Hydroxyindoleacetic Acid (5-HIAA) Collection

The dietary restriction advice provided by Australian clinical laboratories to patients prior to 24-hour urine collection of 5-hydroxyindoleacetic acid (5-HIAA) has not been standardised. Variation exists between the lists of foods and medications patients are requested to avoid and in the duration for which the restrictions must be applied. Furthermore, the evidence for some of these restrictions is limited or outdated. A review of current literature identified that the main foods which significantly elevate urine 5-HIAA levels are plantain, banana, walnuts, hickory nuts, pineapple, plums, tomatoes, kiwifruits and avocados. These need to be avoided for at least two days prior to and during the collection period. Alcohol should be avoided for a minimum of one day before the collection and dietary supplements containing 5-hydroxytryptophan should be avoided for at least 14 days prior. Certain medications may cause false elevations of 5-HIAA but many are dependent on the assay used. Contrary to historical recommendations, we found insufficient information to warrant restriction of eggplant/aubergine, coffee, tea, milk chocolate and vanilla.

The FVB mouse strain as a spontaneous model of degenerative mitral valve disease

Mitral valve disease is a complex entity with diverse origins, degeneration occurring following an extrinsic aggression (infection, autoimmune attack, drug), genetic malformation or being due to a hemodynamic abnormality (dilatation of the left ventricle, myocardial infarction). The aim is to present the main cardiovascular characteristics of the FVB mouse strain with a particular focus on spontaneous mitral valve degeneration and the serotonergic system in comparison with the C57BL/6 J, the usual background strain of many cardiovascular studies. Body weight, systolic blood pressure, heart rate, urinary 5-hydroxyindoleacetic acid (5-HIAA), whole blood and plasma serotonin, tail bleeding time, blood cell count, plasma TGF-β1 and plasma natriuretic peptide concentrations were measured in FVB/NJ and FVB/NRj mice strains (males and females) obtained from Janvier and Charles River Labs in comparison to the usual C57BL/6 background at different ages (12, 16, 20 and 24-week-old). To know if the mitral valve was remodeled, cardiac anatomy and function were assessed by echocardiography and mitral valves were finally characterized by histology. The expression of 5-HT2A and 5-HT2B receptors was measured by RTqPCR in the anterior leaflet of the valve. No significant difference in C57BL/6 J compared to FVB mice strains regarding body weight increase, arterial blood pressure and heart rate was observed. A progressive augmentation of plasma pro-ANP was observed in FVB mice. However, no cardiac hypertrophy or left-ventricular fibrosis were observed. Conversely, FVB mice demonstrated a high prevalence of fibromyxoid highly cellularized and enriched in glycosaminoglycans lesions, inducing major mitral leaflets thickening without increase in length (100% of 24-week-old FVB/NRj males). The increased thickness was correlated with urinary 5-HIAA and blood platelet count. Whole blood serotonin concentration was similar in the two strains but, in FVB, a reduction of plasma serotonin was observed together with an increase of the bleeding time. No difference regarding serotonergic receptors expression was observed. Finally, echocardiography identified left atrial and left ventricular remodeling associated with thickening of both mitral leaflets and mitral insufficient in 30% of FVB mice but no systolic protrusion of mitral leaflets towards the atrium meaning the absence of mitral valve prolapse. Spontaneous mitral myxomatous degeneration is highly prevalent in FVB mice. A contribution of the serotonergic system is suggested

Development, validation and standardization of urinary 5-hydroxyindoleacetic acid determination by LC-MS/MS for implementation in quality-controlled environments

Carcinoid tumors referred to neuroendocrine neoplasms that often are indolent and may not became clinical apparent until there has been metastatic spread. Urinary 5-hydroxyindoleacetic acid (5-HIAA) was recommended as a first-line screening biomarker for the diagnosis and follow-up of carcinoid tumors. The measurement of this analyte is conventionally performed by spectrophotometer or high performance liquid chromatography, and has switched to liquid chromatography-tandem mass spectrometry (LC-MS/MS) recently. In this study, a fast, simple and reliable LC-MS/MS method has been developed and validated for 24 h urinary 5-HIAA determination and the quality assurance referring to post-implementation monitoring has been explored. 50 μL of urine was mixed with 200 μL of a 50% methanol/water solution containing the internal standard 5-HIAA-d5. The mixture was centrifuged and the supernatant was used for direct analysis by LC-MS/MS. The retention time of 5-HIAA is 2.37 min and a total run time is 4 min. This method was validated for excellent linearity from 0.675 to 43.3 μM with CVs ≤ 6.64% and good recovery in the range of 87.1%-107%. No obvious matrix effect was observed. Intra- and inter-day imprecision were below 3.95% and 4.66% respectively. The reference interval of 24-hour urinary 5-HIAA in Chinese adults was established. The quality assurance could ensure reliable and comparable results in routine clinical testing. Thus, this fast, simple and reliable LC-MS/MS method could be proposed as a tool for clinical testing of urinary 5-HIAA in quality-controlled environments.

Diagnostic problem of Primary Hepatic Neuroendocrine Tumor in 18-year-old woman: A case report.

Introduction and importancePrimary Hepatic Neuroendocrine Tumor (PHNET) is a very rare case and it's quite challenging to diagnose and treat. There are approximately 300 cases reported. Among them, only two giant PHNET cases were found in children under 20 years old.Case presentationWe reported an unusual giant PHNET that was found in 18 years old female followed by intra-tumoral bleeding, which was initially misdiagnosed as Hemangioma. Abdominal Computed Tomography (CT) imaging showed a large liver mass with the peripheral enhancing nodular solid part in the delayed phase, which resembled Hemangioma.Clinical discussionPreoperative diagnosis of a Primary Hepatic Neuroendocrine Tumor is difficult as the liver often becomes the site of Neuroendocrine Tumor metastasis from other gastrointestinal organs, rarely occurred in people under 20 years of age, and the CT scan looks like Hemangiomas. The clinical symptoms are not typical, so other specific diagnostic tools for Neuroendocrine Tumor such as Chromogranin A level and 24-hour 5-hydroxyindoleacetic acid urine test are not performed. The indication of hepatic resection is made based on the preoperative diagnosis of other conditions such as large tumor size or tumor complications. Intraoperative diagnosis is also not typical for PHNET, so the definitive diagnosis of PHENT is made from post-resection histopathology.ConclusionThe preoperative diagnosis of this rare tumor is still a big challenge. The physicians should be alert when finding Giant Hemangioma of the Liver, and Neuroendocrine Tumor should be the differential diagnosis. Blood Chromogranin A, urine 5-hydroxyindoleacetic acid test, and Positron Emission Tomography (PET) scan should also be considered.

Platelet, Plasma, Urinary Tryptophan-Serotonin-Kynurenine Axis Markers in Hyperacute Brain Ischemia Patients: A Prospective Study.

Background and Purpose: Ischemic stroke is one of the most common causes of morbidity and mortality and has numerous clinical mimics. Previous studies have suggested a potential role of the tryptophan-serotonin (5-HT)-kynurenine (TSK) axis in ischemic stroke. Studies assessing this axis in the hyperacute phase of ischemic stroke (<4.5 h) are lacking. This prospective study thus evaluates the TSK axis in transient ischemic attack (TIA) and hyperacute ischemic stroke (AIS) patients.Methods: This study included 28 patients (24 AIS and 4 TIA) and 29 controls. The blood and urine samples of patient were collected within 4.5 h of symptoms onset (day 0, D0), then at 24 h and 3 months. Control blood and urine samples were collected once (D0). The TSK axis markers measured were platelet serotonin transporter (SERT) and 5-HT2A receptor (5-HT2AR) densities and platelet, plasma, and urinary 5-HT, plasma and urinary 5-hydroxyindole acetic acid (5-HIAA), and plasma kynurenine and tryptophan (TRP) levels.Results: At D0, patients exhibited a lower (p = 10−5) platelet SERT density, higher (p < 10−6) platelet 5-HT2AR density, higher (p = 10−5) plasma kynurenine/tryptophan (K/T) ratio, and higher urinary 5-HT (p = 0.011) and 5-HIAA (p = 0.003) levels than controls.Conclusions: We observed, for the first time, a hyperacute dysregulation of the serotonergic axis, and hyperacute and long-lasting activation of the tryptophan-kynurenine pathway in brain ischemia.

Quantification of 5-Hydroxyindoleacetic Acid in Urine by Ultra-performance Liquid Chromatography Tandem Mass Spectrometry.

Serotonin (5-hydroxytryptamine) is a neurotransmitter produced in excess by carcinoid tumors, which develop from enterochromaffin cells. 5-Hydroxyindoleacetic acid (5-HIAA) is the primary urinary metabolite of serotonin, making measurement of 5-HIAA useful in the diagnosis and management of carcinoid tumors. Here we describe a simple, inexpensive, and fast method for the detection and quantification of 5-HIAA in urine. Samples are prepared by simple 1:1 dilution. The instrumental analysis is performed by chromatographic separation on a reverse-phase analytical column followed by detection using a triple quadrupole mass spectrometer with electrospray ionization in positive ion mode. Data are acquired by multiple reaction monitoring (MRM).

Principles of Surgical Management of Small Intestinal NET.

Simple SummarySmall-intestinal neuroendocrine tumors (siNETs) account for 25% of gastroenteropancreatic NETs. A total of 89% of multiple tumors are located in the ileum, often within 100 cm of the ileocecal valve. According to current guidelines, all localized siNETs should be considered for radical resection with lymphadenectomy. The preoperative workout should focus on symptoms of carcinoid syndrome (flush, diarrhea, and cardiac failure). Morphological evaluation should include a CT scan with a thin-slice arterial CT, a PET/CT with 68 Ga, and a hepatic MRI. Levels of 24 h urinary 5-hydroxyindoleacetic acid are needed. Regarding surgery, the limiting component is the number of free jejunal branches allowing a resection without risk of short small bowel syndrome. In case of emergency surgery, there is expert agreement that it is not reasonable to initiate resection of the mesenteric mass without comprehensive workup and mapping. The challenge lies in the ability to propose a resection without imposing short small bowel syndrome on the patients.Introduction: Small-intestinal neuroendocrine tumors (siNETs) account for 25% of gastroenteropancreatic NETs. Multiple siNETs appear to develop in a limited segment of the small bowel (SB), 89% of them being located in the ileum, most often within 100 cm of the ileocecal valve (ICV). According to the European Neuroendocrine Tumor Society (ENETS) and the American Joint Committee on Cancer (AJCC), all localized siNETs should be considered for radical surgical resection with adequate lymphadenectomy irrespective of the absence of lymphadenopathy or mesenteric involvement. Surgical management of siNETs: The preoperative workout should include a precise evaluation of past medical and surgical history, focusing on the symptoms of carcinoid syndrome (flush, diarrhea, and cardiac failure). Morphological evaluation should include a CT scan including a thin-slice arterial CT, a PET/CT with 68 Ga, and a hepatic MRI in cases of suspected metastasis. Levels of 24 h urinary 5-hydroxyindoleacetic acid are needed. Regarding surgery, the limiting component is the number of free jejunal branches allowing a resection without risk of short small bowel syndrome. The laparoscopic approach has been poorly studied, and open laparotomy remains the gold standard to explore the abdominal cavity and entirely palpate the small bowel through bidigital palpation and compression. An extensive lymphadenectomy is required. A prophylactic cholecystectomy should be performed. In case of emergency surgery, current recommendations are not definitive. However, there is expert agreement that it is not reasonable to initiate resection of the mesenteric mass without comprehensive workup and mapping. Conclusion: The surgery of siNETs is in constant evolution. The challenge lies in the ability to propose a resection without imposing short small bowel syndrome on the patients. The oncological benefits supported in the literature led to recent changes in the recommendations of academic societies. The next steps remain the dissemination of reproducible quality criteria to perform these procedures.