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BACKGROUND: Delayed diagnosis of hypothyroidism may result in atypical presentations. Here, we report a case with decreased serum level and activity of von Willebrand factor due to untreated profound hypothyroidism. OBSERVATION: A 9-year-old girl, presented with prolonged gingival bleeding after dental extraction. Clinical findings of the case were consistent with hypothyroidism, and the laboratory workup results revealed decreased serum level and activity of von Willebrand factor associated with profound hypothyroidism. Restoration of euthyroidism normalized the coagulation parameters. CONCLUSION: Delayed diagnosis of hypothyroidism may lead to atypical presentations such as bleeding diathesis. Profound hypothyroidism should be considered in the differential diagnosis of acquired von Willebrand disease to avoid undue treatment.
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Transtornos Hemorrágicos , Hipotireoidismo , Doenças de von Willebrand , Feminino , Humanos , Criança , Fator de von Willebrand , Hipotireoidismo/complicações , Doenças de von Willebrand/complicações , Extração Dentária/efeitos adversosAssuntos
Antitireóideos/uso terapêutico , Doença de Graves/diagnóstico , Proteinúria/diagnóstico , Adolescente , Biópsia , Feminino , Doença de Graves/complicações , Doença de Graves/tratamento farmacológico , Doença de Graves/urina , Humanos , Rim/patologia , Metimazol/uso terapêutico , Proteinúria/etiologia , Proteinúria/patologia , Proteinúria/urinaAssuntos
Antitireóideos/uso terapêutico , Glomerulonefrite Membranosa/diagnóstico , Doença de Graves/diagnóstico , Proteinúria/diagnóstico , Adolescente , Biópsia , Diagnóstico Diferencial , Feminino , Membrana Basal Glomerular/patologia , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/etiologia , Glomerulonefrite Membranoproliferativa/diagnóstico , Glomerulonefrite Membranosa/tratamento farmacológico , Glomerulonefrite Membranosa/etiologia , Glomerulonefrite Membranosa/patologia , Doença de Graves/complicações , Doença de Graves/tratamento farmacológico , Doença de Graves/urina , Humanos , Metimazol/uso terapêutico , Nefrose Lipoide/diagnóstico , Nefrose Lipoide/etiologia , Proteinúria/tratamento farmacológico , Proteinúria/etiologia , Proteinúria/patologia , Rituximab/uso terapêutico , Resultado do TratamentoRESUMO
Introduction: Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disease resulting from isolated glucocorticoid deficiency or unresponsiveness to adrenocorticotropic hormone. Patients with FGD usually present in infancy or early childhood with hyperpigmentation, recurrent infections, and hypoglycemia. The salt-wasting crisis is rare. Case Presentation: A term female neonate was admitted to the neonatal intensive care unit due to respiratory distress. On physical examination, she had generalized hyperpigmentation. Initial laboratory work-up yielded normal serum electrolytes and glucose. Hyponatremia and hyperkalemia emerged on follow-up. The patient was diagnosed as having primary adrenal insufficiency (PAI) with elevated plasma adrenocorticotropin hormone and reduced cortisol levels and hydrocortisone. We started on oral sodium (5 mEq/kg/day) and fludrocortisone (FC) (0.2 mg/day) treatment to the patient. Ultrasonography revealed hypoplastic adrenal glands. Molecular genetic analysis revealed a previously reported homozygous pathogenic variant NM_000529.2: c.560delT (p.V187fs*29) in the MC2R gene. FC dose was tapered to 0.05 mg/day on the third month of life and was stopped at tenth months of age with maintenance of normal serum electrolytes and clinical findings. Conclusion: FGD due to MC2R gene mutation may rarely present with a salt-wasting crisis in the neonatal period. Identifying the causative gene with the pathogenic variant in PAI may serve to individualize a treatment plan.
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Introduction: Craniopharyngiomas (CPG) have complex challenges in treatment due to their proximity to vital structures, surgical and radiotherapeutic complexities, and the tendency for recurrence. This study aims to identify the prevalence of endocrine and metabolic comorbidities observed during initial diagnosis and long-term follow-up in a nationwide cohort of pediatric CPG patients. The study also highlights the associated difficulties in their management. Methods: Sixteen centers entered 152 patients into the ÇEDD NET data system. We evaluated the clinical and laboratory characteristics at presentation, administered treatments, accompanying endocrine, metabolic, and other system involvements, and the patient's follow-up features. Results: Of the evaluated patients, 64 were female, and 88 were male. At presentation, the mean age was 9.1 ± 3.67 (min:1.46-max:16.92) years. The most common complaints at presentation were headache (68.4%), vision problems (42%), short stature (15%), nausea and vomiting (7%). The surgical procedure applied to the patients was gross total resection (GTR) in 97 cases (63.8%) and subtotal resection in 55 cases (36.2%). Radiotherapy was initiated in 11.8% of the patients. In the pathological examination, 92% of the cases were adamantinamatous type, 8% were papillary type. Postoperatively, hormone deficiencies consisted of thyroid-stimulating hormone (92.1%), adrenocorticotropic hormone (81%), antidiuretic hormone (79%), growth hormone (65.1%), and gonadotropin (43.4%) deficiencies. Recombinant growth hormone treatment (rhGH) was initiated on 27 patients. The study showed hesitancy among physicians regarding rhGH. The median survival without relapse was 2.2 years. Median time of relapse was 1.82 years (range: 0.13-10.35 years). Relapse was related to longer follow-ups and reduced GTR rates. The median follow-up time was 3.13 years. Among the last follow-up visits, the prevalence of obesity was 38%, but of these, 46.5% were already obese at diagnosis. However, 20% who were not obese at baseline became obese on follow-up. Permanent visual impairment was observed in 26 patients, neurological deficits in 13 patients, and diabetes mellitus in 5 patients. Conclusion: Recurrence was predominantly due to incomplete resection and the low rate of postoperative radiotherapy. It also emphasized challenges in multidisciplinary regular follow ups and suggested early interventions such as dietary restrictions and increased exercise to prevent obesity.
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OBJECTIVE: The risk of malignancy in pediatric thyroid nodules is higher compared to the risk in adults. Our aim was to investigate the clinical, radiological, and histopathological characteristics of pediatric thyroid nodules. MATERIALS AND METHODS: The data of 132 children and adolescents who had thyroid nodules were collected retrospectively from medical records. RESULTS: The mean age of the patients was 12.07 ± 4.08 years and 67% were female. Fine-needle aspiration biopsy was performed in 86 patients (65%) and the results were as follows: benign in 53.4% (n = 46), atypia or follicular lesion of undetermined significance in 3.5% (n = 3), suspicious for follicular neoplasia in 2.3% (n = 2), and malignancy in 32.5% (n = 28). The overall malignancy rate was 22.7% (n = 30). Malignancy was detected after surgery in 2 thyroid nodules belonging to the atypia or follicular lesion of undetermined significance category. Malignancy was detected in 7 patients who had autoimmune thyroiditis and in 1 patient who had congenital dyshormonogenesis. The malignancy rate of the nodules in the patients, who had autoimmune thyroiditis, was found to be 13.4%. Mixed echogenicity, microcalcifications, nodules larger than 10 mm, abnormal lymph nodes, and irregular borders were more common in the malignant group. The nodule size, abnormal lymph nodes, and irregular borders were found to be significant in terms of predicting malignancy. CONCLUSION: We found malignancy in 22.7% of the thyroid nodules, and the malignancy rate of nodules in the patients, who had autoimmune thyroiditis, was 13.4%. The nodule size, abnormal lymph nodes, and irregular nodule borders emerged as the most significant risk factors for malignancy.
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Introduction: Primary adrenal insufficiency associated with cardiomyopathy has been rarely reported in children. We report a case of left ventricular (LV) systolic dysfunction related to adrenal insufficiency with autoimmune polyendocrine syndrome type 1 (APS1). Case Presentation: A 7-year-old girl presented with a loss of consciousness. She had hyperpigmentation over joints and enamel hypoplasia. Laboratory tests showed hypoglycemia, hyponatremia, hypocalcemia, and hyperphosphatemia. Endocrine evaluations revealed low serum parathyroid hormone, low cortisol, and high ACTH. Echocardiography showed moderate to severe mitral regurgitation and LV systolic dysfunction. Serum pro-brain natriuretic peptide (pro-BNP) level was high (2,348 pg/mL). Adrenal insufficiency, hypoparathyroidism, and enamel dysplasia suggested APS1. A novel homozygous variant in the AIRE gene, NM_000383, p.Cys322Arg (c.964T>C) confirmed the diagnosis. Calcium, calcitriol, and hydrocortisone treatments were started. Serum pro-BNP level returned to normal, and LV systolic function improved. Conclusion: Here, we present a case of adrenal insufficiency and hypoparathyroidism associated with LV systolic dysfunction whose cardiac findings improved completely with hydrocortisone and calcitriol treatments. Our case is the second reported case of APS1 presenting with LV dysfunction.
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OBJECTIVE: Mercury poisoning is a condition with multiple-organ dysfunction that has effects on the central nervous system, gastrointestinal system, cardiovascular system, skin, lungs, and kidneys. It can be fatal or may result in sequelae such as neurological disturbances, if treated late or left untreated. The endocrinological effects of mercury exposure are not well-known. We aimed to evaluate patients with mercury poisoning. MATERIALS AND METHODS: A total of 6 cases of mercury poisoning from 3 families were included in the study. Clinical, laboratory, and follow-up data were recorded. RESULTS: Thyroid dysfunction was presented as high thyroid hormones and normal thyrotropin level (unsuppressed) in 5 cases (83.3%). On the other hand, pheochromocytoma-like syndrome was detected in 5 cases (83.3%) with hypertension. The 4 cases were the first to use methimazole for mercury poisoning due to tachycardia and hypertension despite antihypertensive treatment due to catecholamine excess and thyroid dysfunction. Hyponatremia was detected in 3 cases (50%). CONCLUSION: Mercury poisoning is difficult to diagnose because it is rare and presents with nonspecific physical and laboratory findings. Early diagnosis and providing appropriate treatment are essential in order to prevent sequelae. Mercury poisoning should be considered in patients with unexplained hypertension and tachycardia suggesting the involvement of thyroid hormones and catecholamines.
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OBJECTIVE: Spexin (SPX) is a novel peptide implicated in food intake and satiety. SPX levels are reduced in obese patients. AIM: This study aimed to compare serum SPX levels in obese adolescents versus healthy controls and to assess the associations of metabolic syndrome (metS) antecedents with serum SPX levels. METHODS: Eighty consecutive obese adolescents aged 10-18 years and 80 healthy peers were enrolled. Anthropometric measurements, pubertal examinations, and clinical blood pressure measurements were performed. Fasting blood samples were drawn for glucose, insulin, lipids, uric acid, alanine aminotransferase (ALT), and SPX. metS was diagnosed using International Diabetes Federation criteria. Associations of serum SPX with clinical and laboratory variables were assessed. RESULTS: Obese adolescents had lower serum SPX levels than healthy peers (50 pg/mL [25-75% IQR: 25-98 pg/mL] and 67.0 pg/mL [25-75% IQR: 32.5-126.0 pg/mL]; respectively, p = 0.035). Twenty (25%) obese adolescents were diagnosed as having metS. Obese adolescents with metS had lower SPX than those without metS (24.5 pg/mL [25-75% IQR: 15.3-49.5 pg/mL] and 69.0 pg/mL [25-75% IQR: 42.0-142.0 pg/mL]; respectively, p < 0.0001). The frequencies of hyperuricemia, IR, and elevated ALT were similar in obese adolescents with metS and those without metS (p > 0.05 for all). Serum uric acid levels were correlated significantly with serum SPX after correcting for BMI and HOMA-IR (r = -0.41, p < 0.05). A serum SPX level at a cutoff level of 49.5 pg/mL predicted the presence of metS in obese adolescents with 75% sensitivity and 71% specificity. CONCLUSIONS: Obese adolescents have reduced SPX levels, and this reduction is more pronounced in those with metS. Further research is needed to verify the utility of SPX as a biomarker in the diagnosis of metS in obese adolescents.
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Resistência à Insulina , Síndrome Metabólica , Obesidade Infantil , Adolescente , Criança , Humanos , Insulina , Obesidade Infantil/complicações , Ácido ÚricoRESUMO
OBJECTIVES: Wolfram syndrome (WS) is a rarely seen autosomal recessive multisystem neurodegenerative disorder caused by mutations in the WFS1 gene. CASE PRESENTATION: Three sisters with WS had diabetes mellitus (DM) at 4 years of age and optic atrophy. In addition, the first case had hearing impairment, and the second case had diabetes insipidus and urinary incontinence. Linagliptin was administered to the first case as add-on therapy to intensive insulin treatment 15 years after the onset of DM, and her insulin need showed a dramatic decrease. The third case had a remission phase one month after the onset of DM. CONCLUSIONS: Even in cases with the same mutation, symptoms and findings may widely vary in WS. Remission of diabetes has rarely been reported in WS. Also, this report describes the first trial of a dipeptidyl peptidase-4 inhibitor in a patient with WS which provided a decrease in exogenous insulin need.
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Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Insulina/uso terapêutico , Proteínas de Membrana/genética , Mutação , Síndrome de Wolfram/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Quimioterapia Combinada , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Linhagem , Prognóstico , Indução de Remissão , Síndrome de Wolfram/metabolismo , Síndrome de Wolfram/patologiaRESUMO
OBJECTIVE: We hypothesized that diabetic kidney disease (DKD) begins early, before albuminuria occurs. We therefore aimed to assess potential early urinary biomarkers of DKD in normoalbuminuric and normotensive children and adolescents with type 1 diabetes (T1D) to evaluate the relationship between these markers and clinical and laboratory risk factors for DKD. METHODS: This cross-sectional study included 75 children and adolescents with T1D (62% females, mean age 13.9 ± 3.2 years) with normoalbuminuria (an albumin/creatinine ratio [ACR] below 30 mg/g creatinine). Fifty-five age- and sex-matched healthy children and adolescents served as controls. For the assessment of early DKD, urinary levels of angiotensinogen (AGT), transferrin, nephrin, vascular endothelial growth factor-A (VEGF-A), and kidney injury molecule-1 (KIM-1) were measured in adequately collected 24-h urine samples using enzyme-linked immunoassays. RESULTS: The mean disease duration was 7.3 ± 3.2 (range 2.1-15.7) years, and the mean HbA1c level was 8.8 ± 1.4%. The median levels of urine VEGF-A/Cr, AGT/Cr, and transferrin/Cr were significantly higher in normoalbuminuric patients with T1D, compared with those of controls (p < 0.001, p = 0.02, and p = 0.001, respectively), but there was no difference in nephrin/Cr and KIM-1/Cr between the 2 groups. Although none of the patients had albuminuria, the median level of urine ACR was significantly higher in the patient group than the control group (p = 0.003). The ACR was positively correlated with glomerular filtration rate (GFR). Urinary transferrin/Cr, AGT/Cr, and VEGF-A/Cr were significantly correlated with ACR, but not with either GFR or diabetic risk factors including HbA1c or disease duration. CONCLUSION: Normoalbuminuric and normotensive children and adolescents with T1D have elevated urinary VEGF, AGT, and transferrin levels, which may indicate the development of DKD before albuminuria occurs.
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Diabetes Mellitus Tipo 1 , Nefropatias Diabéticas , Adolescente , Angiotensinogênio , Biomarcadores , Criança , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/etiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Transferrina , Fator A de Crescimento do Endotélio VascularRESUMO
Corticosterone methyloxidase deficiency type 2 is an autosomal recessive disorder presenting with salt loss and failure to thrive in early childhood and is caused by inactivating mutations of the CYP11B2 gene. Herein, we describe four Turkish patients from two families who had clinical and hormonal features compatible with corticosterone methyloxidase deficiency and all had inherited novel CYP11B2 variants. All of the patients presented with vomiting, failure to thrive and severe dehydration, except one patient with only failure to thrive. Biochemical studies showed hyponatremia, hyperkalemia and acidosis. All patients had normal cortisol response to adrenocorticotropic hormone stimulation test and had elevated plasma renin activity with low aldosterone levels. Three patients from the same family were found to harbor a novel homozygous variant c.1175T>C (p.Leu392Pro) and a known homozygous variant c.788T>A (p.Ile263Asn) in the CYP11B2 gene. The fourth patient had a novel homozygous variant c.666_667delCT (p.Phe223ProfsTer35) in the CYP11B2 gene which caused a frame shift, forming a stop codon. Corticosterone methyloxidase deficiency should be considered as a differential diagnosis in patients presenting with hyponatremia, hyperkalemia and growth retardation, and it should not be forgotten that this condition is life-threatening if untreated. Genetic analyses are helpful in diagnosis of the patients and their relatives. Family screening is important for an early diagnosis and treatment. In our cases, previously unreported novel variants were identified which are likely to be associated with the disease.
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Citocromo P-450 CYP11B2/genética , Hipoaldosteronismo/genética , Pré-Escolar , Feminino , Humanos , Hipoaldosteronismo/metabolismo , Hipoaldosteronismo/fisiopatologia , Lactente , Masculino , LinhagemRESUMO
Objective: To investigate clinical characteristics and response to growth hormone (GH) treatment in patients with Prader-Willi syndrome (PWS) in Turkey. Methods: The data of 52 PWS patients from ten centers was retrospectively analyzed. A nation-wide, web-based data system was used for data collection. Demographic, clinical, genetic, and laboratory data and follow-up information of the patients were evaluated. Results: The median age of patients at presentation was 1.5 years, and 50% were females. Genetic analysis showed microdeletion in 69.2%, uniparental disomy in 11.5%, imprinting defect in 1.9% and methylation abnormality in 17.3%. Hypotonia (55.7%), feeding difficulties (36.5%) and obesity (30.7%) were the most common complaints. Cryptorchidism and micropenis were present in 69.2% and 15.3% of males, respectively. At presentation, 25% had short stature, 44.2% were obese, 9.6% were overweight and 17.3% were underweight. Median age of obese patients was significantly higher than underweight patients. Central hypothyroidism and adrenal insufficiency were present in 30.7% and 4.7%, respectively. Hypogonadism was present in 75% at normal age of puberty. GH treatment was started in 40% at a mean age of 4.7±2.7 years. After two years of GH treatment, a significant increase in height SDS was observed. However, body mass index (BMI) standard deviation (SDS) remained unchanged. Conclusion: The most frequent complaints were hypotonia and feeding difficulty at first presentation. Obesity was the initial finding in 44.2%. GH treatment was started in less than half of the patients. While GH treatment significantly increased height SDS, BMI SDS remained unchanged, possibly due to the relatively older age at GH start.
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Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Prader-Willi/tratamento farmacológico , Adolescente , Desenvolvimento do Adolescente , Fatores Etários , Estatura , Índice de Massa Corporal , Criança , Desenvolvimento Infantil , Pré-Escolar , Feminino , Predisposição Genética para Doença , Hormônio do Crescimento Humano/efeitos adversos , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/genética , Síndrome de Prader-Willi/fisiopatologia , Estudos Retrospectivos , Resultado do Tratamento , TurquiaRESUMO
Carney complex (CNC) is a multiple neoplasia syndrome, characterized by pigmented lesions of the skin and mucosa, cardiac, cutaneous and other myxomas and multiple endocrine and non-endocrine tumors. Most of the cases have an inactivating mutation in the PRKAR1A gene. Osteochondromyxoma (OMX) is an extremely rare myxomatous tumor of bone, affecting 1% of CNC patients. Large cell calcifying Sertoli cell tumor (LCCSCT) is a testicular tumor affecting more than 75% of males with CNC. Here, we report an atypical case of CNC without typical pigmented skin lesions, presenting with a bone based tumor as the first manifestation. Initial presentation was for a recurrent, locally invasive intranasal tumor without definite diagnosis. Further clinical developments during follow up, central precocious puberty and testicular tumor with calcification, led to the diagnosis of LCCSCT, a CNC-related tumor. Histopathologic examination of the intranasal tumor was re-evaluated with this knowledge and OMX was diagnosed. Coexistence of OMX and LCCSCT suggested CNC. Genetic analysis revealed a heterozygous non-sense p.Trp 224* (c.672G>A) in the PRKAR1A gene. In our case, the diagnosis of OMX was delayed, because it is extremely rare and little is known about this tumor. Thus the aim of this report was to alert other clinicians to consider CNC if OMX is diagnosed.
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Neoplasias Ósseas , Complexo de Carney , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Osteocondroma , Tumor de Células de Sertoli , Neoplasias Testiculares , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/etiologia , Neoplasias Ósseas/genética , Complexo de Carney/complicações , Complexo de Carney/diagnóstico , Complexo de Carney/genética , Criança , Humanos , Masculino , Osteocondroma/diagnóstico , Osteocondroma/etiologia , Osteocondroma/genética , Tumor de Células de Sertoli/diagnóstico , Tumor de Células de Sertoli/etiologia , Tumor de Células de Sertoli/genética , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/etiologia , Neoplasias Testiculares/genéticaRESUMO
Donohue syndrome (DS) and Rabson-Mendenhall syndrome (RMS) are rare diseases caused by biallelic variants within the insulin receptor gene (INSR). Here, we report 2 cases: one with DS and the other with RMS. The case with DS presented with intrauterine growth retardation, nipple hypertrophy, clitoromegaly, distended abdomen, hypertrichosis, and dysmorphic features. The second case showed severe acanthosis nigricans, hyperkeratosis, and hypertrichosis. In both cases, abnormal glucose homeostasis due to severe insulin resistance was observed. The diagnosis of DS and RMS was established based on clinical characteristics, abnormal glucose homeostasis, high serum insulin levels, and determination of pathogenic variants in the INSR gene. The first case with DS has 2 novel homozygous variants, NM_000208.3, c.3122delA (p.N1041Mfs*16) and c.3419C>G (p.A1140G), and the second case with RMS has a previously reported homozygous variant NM_000208.3, c.3529+5G>A (IVS19+5G>A) in the INSR gene.
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von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited disorder, characterized by hemangioblastomas of the retina and central nervous system (CNS); renal cysts; clear cell carcinoma; pheochromocytoma (PCC); endolymphatic sac tumors; cystadenomas of the epididymis in males; broad ligament of uterus in females; pancreatic cysts; cystadenomas; and neuroendocrine tumors. We report two cases of VHL disease that presented with PCC as the first manifestation. Further clinical developments during follow-up, hemangioblastoma of CNS in one case and a pancreatic neuroendocrine tumor (PNET) in the second case led to the diagnosis of VHL disease. Genetic analyses of the two cases revealed p.Arg161Gln (c.482G>A) and p.Leu129Pro (c.386T>G) heterozygous missense mutations in the VHL gene, respectively. In children, PCC may be the only and/or initial manifestation of VHL with delayed manifestations of the syndrome in other organs. PNET is a very rare manifestation of VHL disease. To the best of our knowledge, this is only the second reported case presenting with a combination of a PNET and bilateral PCC as components of childhood VHL disease. Pediatric patients diagnosed with PCC should be investigated for genetic causes and especially for VHL.
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Neoplasias das Glândulas Suprarrenais/diagnóstico , Hemangioblastoma/diagnóstico , Tumores Neuroendócrinos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Feocromocitoma/diagnóstico , Doença de von Hippel-Lindau/diagnóstico , Neoplasias das Glândulas Suprarrenais/etiologia , Criança , Feminino , Hemangioblastoma/etiologia , Humanos , Masculino , Tumores Neuroendócrinos/etiologia , Neoplasias Pancreáticas/etiologia , Feocromocitoma/etiologia , Doença de von Hippel-Lindau/complicaçõesRESUMO
The aim of this study was to determine the frequency of vitamin D deficiency and/or insufficiency in children with juvenile idiopathic arthritis (JIA) and familial Mediterranean fever (FMF) and to assess the relationship between vitamin D and disease activity. Sixty four patients with JIA, thirty six patients with FMF and one hundred healthy children were enrolled in this study. Vitamin D levels were measured during activation and remission periods in the patients with JIA and during attack and attack free periods in the patients with FMF. The mean vitamin D levels were found to be 18. 9±11 ng/ml and 18.6±9.2 ng/ml during activation and remission periods of disease, respectively, in the patients with JIA, 16±8.5 ng/ml and 13.1±6.4 ng/ml during attack and attack-free periods, respectively, in the patients with FMF and 26.7±10.5 ng/ml in the healthy children. There was no significant difference between vitamin D levels during activation and remission periods in the patients with JIA, whereas vitamin D levels during attack free periods were lower compared to attack periods in the patients with FMF. No significant relationship was found between disease activity and serum vitamin D levels. The vitamin D levels of the children with JIA and FMF were significantly lower compared to the healthy children. The frequency of vitamin D deficiency and insufficiency was considerably high among the patients with JIA and FMF.