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1.
Laryngoscope ; 126(7): E240-7, 2016 07.
Article in English | MEDLINE | ID: mdl-26485571

ABSTRACT

OBJECTIVES/HYPOTHESIS: Hearing loss and enlarged vestibular aqueduct (EVA) can be inherited as an autosomal recessive trait caused by mutant alleles of the SLC26A4 gene. In some other families, EVA does not segregate in a typical autosomal recessive pattern. The goal of this study was to characterize the SLC26A4 genotypes and phenotypes of extended families with atypical segregation of EVA. STUDY DESIGN: Prospective study of cohort of families ascertained between 1998 and 2014 at the National Institutes of Health Clinical Center. METHODS: Study subjects were members of eight families segregating EVA in at least two members who were not related as siblings. Evaluations included pure-tone audiometry, temporal bone imaging, SLC26A4 nucleotide sequence analysis, SLC26A4-linked marker genotype and haplotype analysis, and pedigree analysis. RESULTS: One family had members with EVA caused by different etiologies, and two families had pseudodominant inheritance of recessive mutations of SLC26A4. In five families, the etiology remained unknown and could include inheritance of mutant alleles at another genetic locus, nongenetic influences, or a combination of these factors. CONCLUSIONS: Familial EVA can demonstrate a variety of atypical segregation patterns. Pseudodominant inheritance of SLC26A4 mutations or recessive alleles of other hearing loss genes may be more likely to occur in families in which deaf individuals have intermarried. The etiologic basis of atypical segregation of EVA without detectable SLC26A4 mutations remains unknown. Future studies of these families may reveal novel genes for EVA. LEVEL OF EVIDENCE: NA Laryngoscope, 126:E240-E247, 2016.


Subject(s)
Chromosome Segregation/genetics , Hearing Loss, Sensorineural/genetics , Hearing Loss/genetics , Membrane Transport Proteins/genetics , Pedigree , Vestibular Aqueduct/abnormalities , Adolescent , Adult , Aged , Alleles , Audiometry, Pure-Tone , Child , Child, Preschool , Female , Genetic Predisposition to Disease , Genotype , Humans , Infant , Male , Middle Aged , Mutation , Phenotype , Prospective Studies , Sulfate Transporters , Temporal Bone/diagnostic imaging , Young Adult
2.
Chest ; 148(4): 1027-1033, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26066372

ABSTRACT

BACKGROUND: Lymphangioleiomyomas occur in 38% of patients with sporadic lymphangioleiomyomatosis (LAM) and may cause pain and increased abdominal girth, mimicking the presence of a malignancy. Lymphatic involvement in LAM is closely associated with elevated serum levels of vascular endothelium growth factor-D (VEGF-D). Because lymphangioleiomyomas undergo diurnal variation in volume, we hypothesized that daytime ingestion of food, by increasing chyle formation and lymphatic flow, is the cause of an increase in lymphangioleiomyoma volume. METHODS: Subjects had abdominopelvic sonograms and blood drawn for measurement of serum VEGF-D levels under nonfasting (day 1) and fasting (day 2) conditions. The size of the lymphangioleiomyomas was determined by a radiologist who was blinded to the subjects' status. The Wilcoxon signed rank test was used to determine whether the nonfasting tumor size was different from the fasting tumor size. RESULTS: Thirty-five women were studied (aged 45.2 ± 8.5 years; FEV1, 82% ± 25%; diffusing capacity of the lung for carbon monoxide, 64% ± 25% predicted). Images suitable for volume measurements were obtained in 30 subjects. Fasting decreased the tumor size by 20.7 ± 39.3 cm3 (24% ± 40%, P < .001). Fasting VEGF-D levels (10,650 ± 900 pg/mL) were not significantly different from nonfasting values (12,100 ± 800 pg/mL, P = .56). CONCLUSIONS: Lymphangioleiomyoma volume decreased during the fasting state. Conversely, a combination of food intake and decreased chyle flow through lymphatics partially obstructed by LAM cells may account for increases in lymphangioleiomyoma size. Imaging studies performed under fasting conditions may help in determining whether an abdominal tumor is a result of LAM or malignancy.


Subject(s)
Abdominal Neoplasms/diagnosis , Fasting , Lymphangioleiomyomatosis/diagnosis , Lymphangiomyoma/diagnosis , Neoplasm Staging , Tomography, X-Ray Computed , Abdominal Neoplasms/blood , Adult , Biomarkers, Tumor/blood , Female , Follow-Up Studies , Humans , Lymphangioleiomyomatosis/blood , Lymphangioleiomyomatosis/complications , Lymphangiomyoma/blood , Lymphangiomyoma/complications , Severity of Illness Index , Vascular Endothelial Growth Factor D/blood
3.
J Clin Endocrinol Metab ; 99(8): E1519-29, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24780051

ABSTRACT

CONTEXT: The effect of obesity and concomitant insulin resistance on pubertal development is incompletely elucidated. OBJECTIVE: To determine how measures of adiposity and insulin resistance are associated with pubertal maturation in boys and girls. SETTING AND DESIGN: Breast and pubic hair Tanner stage and testicular volume by orchidometry were determined by physical examination in 1066 children. Ovarian volume was estimated by trans-abdominal ultrasound. Fat mass, skeletal age, and fasting serum for insulin and glucose, total T, estradiol, estrone, dehydroepiandrosterone-sulfate, and androstenedione were measured at the National Institutes of Health Clinical Research Center. Convenience sample; 52% obese, 59% female. RESULTS: Logistic regression identified a significant interaction between sex and obesity for prediction of pubertal development (P ≤ .01). There was a negative association between boys' testicular volume and body mass index (BMI)/fat mass but a positive association between girls' breast stage and BMI/fat mass. Ovarian volume in girls was positively associated with insulin resistance but not with BMI/fat mass. There was a positive association between obesity and measures of estrogen exposure (breast development and skeletal age) in both sexes. Positive correlations were seen for girls between BMI and pubic hair development and between insulin resistance and T production, whereas adiposity was negatively associated with pubic hair in boys. CONCLUSIONS: Significant sexual dimorphisms in the manifestations of pubertal development are seen in obese girls and boys. Two known effects of obesity, increased peripheral conversion of low-potency androgens to estrogens by adipose tissue-aromatase and increased insulin resistance, may be in large part responsible for these differences.


Subject(s)
Adiposity/physiology , Adolescent Development , Body Mass Index , Child Development , Insulin Resistance , Pediatric Obesity/epidemiology , Puberty/physiology , Sex Characteristics , Adipose Tissue/growth & development , Adolescent , Body Composition , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Female , Health Status Indicators , Humans , Male
4.
Thyroid ; 24(8): 1223-31, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24724719

ABSTRACT

BACKGROUND: Thyroid dysfunction is a common adverse event associated with tyrosine kinase inhibitors (TKI), but its underlying pathophysiology is unclear. Cabozantinib is a novel TKI currently Food and Drug Administration approved for advanced medullary thyroid cancer and tested in clinical trials on solid tumors including prostate, liver, bladder, breast, and ovarian cancer. METHODS: We analyzed the thyroid function of patients enrolled in two phase 2 clinical trials using cabozantinib at the National Institutes of Health Clinical Center. Two cases of thyroiditis associated with cabozantinib therapy are presented in detail, and a systematic review of the literature on TKI-associated thyroid dysfunction is also discussed. RESULTS: Between September 2012 and September 2013, 33 patients were treated with cabozantinib, and follow-up thyroid function tests were available for 31 (20 males, 11 females; age 59±1 years). Thyroid dysfunction was recorded in the majority of patients (93.1%), with a predominance of subclinical hypothyroidism. Two cases showed a biphasic pattern of thyroid dysfunction characterized by a transient thyrotoxicosis followed by hypothyroidism. Color Doppler demonstrated an increase in vascularization during the thyrotoxic phase, but no uptake was visualized on nuclear medicine imaging. A systematic review of the literature resulted in the identification of 40 original manuscripts, of which 13 were case series and 6 were case reports describing TKI-associated thyroid dysfunction. CONCLUSION: TKI therapy often results in clinically significant thyroid dysfunction. Cabozantinib treatment commonly results in thyroid dysfunction varying from subclinical hypothyroidism to symptomatic thyrotoxicosis. Early detection and characterization of cabozantinib-associated thyroid dysfunction and close follow-up are essential to provide adequate management of this common adverse event.


Subject(s)
Anilides/adverse effects , Anilides/therapeutic use , Antineoplastic Agents/therapeutic use , Pyridines/adverse effects , Pyridines/therapeutic use , Sarcoma/drug therapy , Thyroid Diseases/drug therapy , Urinary Bladder Neoplasms/drug therapy , Adult , Aged , Female , Humans , Male , Middle Aged , Neoplasm Metastasis/drug therapy , Protein-Tyrosine Kinases/antagonists & inhibitors , Thyroid Diseases/etiology , Thyroid Gland/diagnostic imaging , Thyrotoxicosis/physiopathology , Ultrasonography, Doppler
5.
J Clin Endocrinol Metab ; 98(3): 989-94, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23348401

ABSTRACT

CONTEXT: Nephrocalcinosis is a complication of hypoparathyroidism and other metabolic disorders. Imaging modalities include ultrasonography (US) and computed tomography (CT). Few studies have compared these modalities, and standard clinical practice is not defined. OBJECTIVE: The objective of the study was to determine the preferred method for assessing nephrocalcinosis. DESIGN: The design of the study was a retrospective, blinded analysis. SETTING: The study was conducted at a clinical research center. PATIENTS: Twenty-two hypoparathyroid subjects and 7 controls participated in the study. INTERVENTIONS: Contemporaneous renal US and CT images were reviewed in triplicate by 4 blinded radiologists. Nephrocalcinosis was classified using a 0-3 scale with 0 meaning no nephrocalcinosis and 3 meaning severe nephrocalcinosis. MAIN OUTCOME MEASURES: Intraobserver, interobserver, and interdevice agreements were measured. RESULTS: Intraobserver agreement was high, with an overall weighted kappa of 0.83 for CT and 0.89 for US. Interobserver agreement was similar between modalities, with kappas of 0.74 for US and 0.70 for CT. Only moderate agreement was found between US and CT scores, with an intermodality kappa of 0.47 and 60% concordance. Of discordant pairs, 81% had higher US scores and only 19% had higher CT scores. Of nephrocalcinosis seen on US and not CT, 45%, 46%, and 9% were grades 1, 2, and 3, respectively. Overall, US scores were higher than CT with a cumulative odds ratio (95% confidence interval) of 5.97 (2.60, 13.75) (P < .01). In controls, 100% of US ratings were 0, and 95% of CT ratings were 0. CONCLUSIONS: US is superior to CT for assessment of mild to moderate nephrocalcinosis in patients with hypoparathyroidism. This finding, in combination with its low cost, lack of radiation, and portability, defines US as the preferred modality for assessment of nephrocalcinosis.


Subject(s)
Hypoparathyroidism/complications , Nephrocalcinosis/diagnostic imaging , Tomography, X-Ray Computed/standards , Ultrasonography/standards , Adolescent , Adult , Child , Female , Follow-Up Studies , Humans , Kidney Medulla/diagnostic imaging , Male , Middle Aged , Nephrocalcinosis/etiology , Observer Variation , Reproducibility of Results , Retrospective Studies , Single-Blind Method , Tomography, X-Ray Computed/methods , Tomography, X-Ray Computed/statistics & numerical data , Ultrasonography/methods , Ultrasonography/statistics & numerical data
6.
World J Otorhinolaryngol ; 3(2): 26-34, 2013 May 28.
Article in English | MEDLINE | ID: mdl-25960948

ABSTRACT

Pendred syndrome (PS) is characterized by autosomal recessive inheritance of goiter associated with a defect of iodide organification, hearing loss, enlargement of the vestibular aqueduct (EVA), and mutations of the SLC26A4 gene. However, not all EVA patients have PS or SLC26A4 mutations. Two mutant alleles of SLC26A4 are detected in » of North American or European EVA populations, one mutant allele is detected in another » of patient populations, and no mutations are detected in the other ½. The presence of two mutant alleles of SLC26A4 is associated with abnormal iodide organification, increased thyroid gland volume, increased severity of hearing loss, and bilateral EVA. The presence of a single mutant allele of SLC26A4 is associated with normal iodide organification, normal thyroid gland volume, less severe hearing loss and either bilateral or unilateral EVA. When other underlying correlations are accounted for, the presence of a cochlear malformation or the size of EVA does not have an effect on hearing thresholds. This is consistent with observations of an Slc26a4 mutant mouse model of EVA in which hearing loss is independent of endolymphatic hydrops or inner ear malformations. Segregation analyses of EVA in families suggest that the patients carrying one mutant allele of SLC26A4 have a second, undetected mutant allele of SLC26A4, and the probability of a sibling having EVA is consistent with its segregation as an autosomal recessive trait. Patients without any mutations are an etiologically heterogeneous group in which siblings have a lower probability of having EVA. SLC26A4 mutation testing can provide prognostic information to guide clinical surveillance and management, as well as the probability of EVA affecting a sibling.

7.
J Clin Endocrinol Metab ; 97(9): E1782-90, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22745241

ABSTRACT

CONTEXT: The testicular phenotype in McCune-Albright syndrome (MAS) has not been well characterized. Boys present with a relatively low incidence of precocious puberty in comparison with girls. Radiographic and histological studies are limited to small series and case reports, which report testicular microlithiasis and Sertoli cell hyperplasia. OBJECTIVE: Our objective was to characterize the biochemical, radiological, and histological spectrum and clinical management of testicular pathology in males with MAS. PATIENTS, DESIGN, AND SETTING: Fifty-four males with MAS participated in this prospective cohort study at a clinical research center. INTERVENTION: Evaluation included testicular exam, pubertal staging, testicular ultrasound, measurement of LH, FSH, and testosterone. Orchiectomies were performed when considered clinically indicated. MAIN OUTCOME MEASURE: Prevalence and characterization of ultrasound lesions with correlation to histology were evaluated. RESULTS: Of 54 males, 44 (81%) presented with ultrasound abnormalities including hyperechoic lesions (49%), hypoechoic lesions (30%), microlithiasis (30%), heterogeneity (47%), and focal calcifications (11%). Eight subjects underwent orchiectomy revealing large foci of Leydig cell hyperplasia, which could not be definitively distinguished from Leydig cell tumor. After no subjects developed clinical malignancy, a conservative approach was instituted, and subsequent subjects were followed with serial imaging. Testosterone and gonadotropins were normal in subjects without precocious puberty or pituitary disease. Eleven (21%) presented with precocious puberty, and a combination of aromatase inhibitors, androgen receptor blockers, and leuprolide resulted in improved predicted adult height. In addition, the first cases of testicular adrenal rest and bilateral germ cell tumors in association with MAS are presented. CONCLUSIONS: Contrary to prevailing thinking, the incidence of gonadal pathology in MAS is equal in males and females. The predominant histopathological finding was Leydig cell hyperplasia, which carries a low risk of malignant transformation and can be managed conservatively.


Subject(s)
Fibrous Dysplasia, Polyostotic/pathology , Fibrous Dysplasia, Polyostotic/therapy , Testicular Diseases/pathology , Testicular Diseases/therapy , Adolescent , Adrenal Cortex Function Tests , Adult , Age of Onset , Child , Child, Preschool , Cohort Studies , Female , Fibrous Dysplasia, Polyostotic/complications , Follicle Stimulating Hormone/blood , Follow-Up Studies , Humans , Infant , Lithiasis/pathology , Longitudinal Studies , Luteinizing Hormone/blood , Male , Middle Aged , Orchiectomy , Prospective Studies , Puberty/physiology , Sertoli Cells/pathology , Testicular Diseases/etiology , Testis/diagnostic imaging , Testis/pathology , Testosterone/blood , Ultrasonography , Young Adult
8.
Cell Physiol Biochem ; 28(3): 545-52, 2011.
Article in English | MEDLINE | ID: mdl-22116369

ABSTRACT

Enlargement of the vestibular aqueduct (EVA) is the most common inner ear anomaly detected in ears of children with sensorineural hearing loss. Pendred syndrome (PS) is an autosomal recessive disorder characterized by bilateral sensorineural hearing loss with EVA and an iodine organification defect that can lead to thyroid goiter. Pendred syndrome is caused by mutations of the SLC26A4 gene. SLC26A4 mutations may also be identified in some patients with nonsyndromic EVA (NSEVA). The presence of two mutant alleles of SLC26A4 is correlated with bilateral EVA and Pendred syndrome, whereas unilateral EVA and NSEVA are correlated with one (M1) or zero (M0) mutant alleles of SLC26A4. Thyroid gland enlargement (goiter) appears to be primarily dependent on the presence of two mutant alleles of SLC26A4 in pediatric patients, but not in older patients. In M1 families, EVA may be associated with a second, undetected SLC26A4 mutation or epigenetic modifications. In M0 families, there is probably etiologic heterogeneity that includes causes other than, or in addition to, monogenic inheritance.


Subject(s)
Hearing Loss, Sensorineural/genetics , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Vestibular Aqueduct/abnormalities , Genotype , Humans , Phenotype , Sulfate Transporters
9.
J Vasc Interv Radiol ; 22(8): 1107-16, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21664144

ABSTRACT

PURPOSE: To evaluate the safety and efficacy of once-daily intraclot injections of low doses (≤ 10 mg) of tissue plasminogen activator (tPA) for thrombolysis of venous thrombosis. MATERIALS AND METHODS: In prospective studies, 33 patients with subclavian, jugular, and central venous thrombosis (SJ-CVT) (all but two cases associated with central catheters) were treated once a day with ≤ 4 mg/day of tPA, and 30 patients with acute deep vein thrombosis of the lower extremity (DVT-LE) < 14 days old were treated once a day with ≤ 10 mg/leg/day of tPA by intraclot "lacing" of thrombus without continuous infusions of tPA. RESULTS: Patency was restored in 26 (79%) of 33 patients with SJ-CVT using an average total dose of 7.1 mg of tPA/per patient and average of 2.1 treatments or days of therapy. Five patients received thrombolytic therapy for SJ-CVT as outpatients. Initial patency was restored in 29 (97%) of 30 patients with acute DVT-LE using an average total dose of 20 mg of tPA per patient over an average of 2.7 treatments/or days per patient. Follow-up imaging examinations at 6 months showed continued patency in 27 (96%)/of 28 patients. There were no major bleeding complications, and no patient required a blood transfusion. CONCLUSIONS: Intraclot injection of low doses of alteplase is effective for acute venous thrombosis, and pharmacokinetic data suggest potentially greater safety.


Subject(s)
Fibrinolytic Agents/administration & dosage , Tissue Plasminogen Activator/administration & dosage , Venous Thrombosis/drug therapy , Acute Disease , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Prospective Studies , Treatment Outcome , Vascular Patency
10.
Adv Otorhinolaryngol ; 70: 43-49, 2011.
Article in English | MEDLINE | ID: mdl-21358184

ABSTRACT

Mutations in SLC26A4 can cause deafness and goiter in Pendred syndrome (PDS) or isolated non-syndromic enlargement of the vestibular aqueduct (NSEVA). PDS is one of the most common hereditary causes of deafness. It is characterized by autosomal-recessive inheritance of sensorineural hearing loss, enlarged vestibular aqueducts (EVA), and an iodide organification defect with or without goiter. The diagnosis is confirmed by detection of two mutant alleles of SLC26A4 in a patient with EVA. The perchlorate discharge test can detect the underlying thyroid biochemical defect and is useful for the evaluation of goiter or for the clinical diagnosis of PDS in a patient with a non-diagnostic SLC26A4 genotype. SLC26A4 encodes the pendrin polypeptide, an anion exchanger that, in recombinant expression systems, transports chloride, bicarbonate, and iodide. Investigation of pendrin function in the inner ear has been facilitated by the Slc26a4(Δ) (knockout) mouse model, but the exact mechanism of its hearing loss remains unclear, as does pendrin's principal transport function in the inner ear. Treatment of PDS is focused upon rehabilitation of hearing loss, and surveillance and management of goiter and, less commonly, hypothyroidism.


Subject(s)
Membrane Transport Proteins/genetics , Vestibular Aqueduct/abnormalities , Alleles , Animals , Goiter, Nodular/genetics , Goiter, Nodular/rehabilitation , Hearing Loss, Sensorineural/genetics , Hearing Loss, Sensorineural/rehabilitation , Humans , Iodides/metabolism , Mice , Mutation , Sulfate Transporters , Thyroid Gland/metabolism
11.
Surgery ; 146(6): 1144-55, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19958942

ABSTRACT

BACKGROUND: We reviewed reoperations for persistent or recurrent sporadic parathyroid adenoma to evaluate and compare our current results and outcomes to our previous experience. METHODS: From 1996 to 2008, 237 patients with persistent or recurrent hyperparathyroidism after failed operation underwent reoperation. Patients were re-explored with the assistance of non-invasive and sometimes invasive imaging. RESULTS: A missed adenoma was suspected pre-operatively in 163 patients. Reoperation resulted in long-term resolution of hypercalcemia in 92%. Adenomas were in entopic locations in 32%; the most frequent ectopic location was the thymus (20%). Sestamibi scanning and ultrasonography were the most successful non-invasive imaging studies (96% positive predictive value (PPV) and 84% PPV respectively). Forty-four percent of patients had a reoperation based solely on non-invasive imaging. Of the invasive procedures performed, arteriography resulted in the best localization (92% PPV). Permanent recurrent laryngeal nerve injury occurred in 1.8%. CONCLUSION: Compared to our prior experience (1982-1995), outcomes remained similar (92% resolution of hypercalcemia and 1.8% recurrent nerve injury currently versus 96% and 1.3% previously). Fewer patients received invasive studies for pre-operative localization (56% vs 73%, respectively). The decreased use of invasive imaging is due to technical improvements and greater confidence in the combination of ultrasonography and sestamibi scanning.


Subject(s)
Adenoma/surgery , Parathyroid Neoplasms/surgery , Adenoma/complications , Adenoma/diagnosis , Adolescent , Adult , Aged , Female , Humans , Hypercapnia/etiology , Hypercapnia/surgery , Hyperparathyroidism/surgery , Male , Middle Aged , Neoplasm Recurrence, Local/complications , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/surgery , Parathyroid Hormone/blood , Parathyroid Neoplasms/complications , Parathyroid Neoplasms/diagnosis , Postoperative Complications/etiology , Recurrent Laryngeal Nerve Injuries , Reoperation , Retrospective Studies , Treatment Outcome , Young Adult
12.
Arch Otolaryngol Head Neck Surg ; 135(7): 670-6, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19620588

ABSTRACT

OBJECTIVE: To evaluate thyroid structure and function in patients with enlargement of the vestibular aqueduct (EVA) and sensorineural hearing loss. DESIGN: Prospective cohort survey. SETTING: National Institutes of Health Clinical Center, a federal biomedical research facility. PATIENTS: The study population comprised 80 individuals, aged 1.5 to 59 years, ascertained on the basis of EVA and sensorineural hearing loss. MAIN OUTCOME MEASURES: Associations among the number of mutant alleles of SLC26A4; volume and texture of the thyroid; percentage of iodine 123 ((123)I) discharged at 120 minutes after administration of perchlorate in the perchlorate discharge test; and peripheral venous blood levels of thyrotropin, thyroxine, free thyroxine, triiodothyronine, thyroglobulin, antithyroid peroxidase and antithyroglobulin antibodies, and thyroid-binding globulin. RESULTS: Thyroid volume is primarily genotype dependent in pediatric patients but age dependent in older patients. Individuals with 2 mutant SLC26A4 alleles discharged a significantly (P < or = .001) greater percentage of (123)I compared with those with no mutant alleles or 1 mutant allele. Thyroid function, as measured by serologic testing, is not associated with the number of mutant alleles. CONCLUSIONS: Ultrasonography with measurement of gland volume is recommended for initial assessment and follow-up surveillance of the thyroid in patients with EVA. Perchlorate discharge testing is recommended for the diagnostic evaluation of patients with EVA along with goiter, nondiagnostic SLC26A4 genotypes (zero or 1 mutant allele), or both.


Subject(s)
Hearing Loss, Sensorineural/physiopathology , Thyroid Gland/physiopathology , Vestibular Aqueduct/pathology , Adolescent , Adult , Child , Child, Preschool , Goiter/genetics , Hearing Loss, Sensorineural/genetics , Humans , Infant , Membrane Transport Proteins/genetics , Middle Aged , Perchlorates , Prospective Studies , Sulfate Transporters , Thyroid Function Tests , Thyroid Gland/diagnostic imaging , Ultrasonography , Young Adult
13.
Hum Mutat ; 30(4): 599-608, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19204907

ABSTRACT

Hearing loss with enlargement of the vestibular aqueduct (EVA) can be associated with mutations of the SLC26A4 gene encoding pendrin, a transmembrane Cl(-)/I(-)/HCO(3)(-) exchanger. Pendrin's critical transport substrates are thought to be I(-) in the thyroid gland and HCO(3)(-) in the inner ear. We previously reported that bi-allelic SLC26A4 mutations are associated with Pendred syndromic EVA whereas one or zero mutant alleles are associated with nonsyndromic EVA. One study proposed a correlation of nonsyndromic EVA with SLC26A4 alleles encoding pendrin with residual transport activity. Here we describe the phenotypes and SLC26A4 genotypes of 47 EVA patients ascertained since our first report of 39 patients. We sought to determine the pathogenic potential of each variant in our full cohort of 86 patients. We evaluated the trafficking of 11 missense pendrin products expressed in COS-7 cells. Products that targeted to the plasma membrane were expressed in Xenopus oocytes for measurement of anion exchange activity. p.F335L, p.C565Y, p.L597S, p.M775T, and p.R776C had Cl(-)/I(-) and Cl(-)/HCO(3)(-) exchange rate constants that ranged from 13 to 93% of wild type values. p.F335L, p.L597S, p.M775T and p.R776C are typically found as mono-allelic variants in nonsyndromic EVA. The high normal control carrier rate for p.L597S indicates it is a coincidentally detected nonpathogenic variant in this context. We observed moderate differential effects of hypo-functional variants upon exchange of HCO(3)(-) versus I(-) but their magnitude does not support a causal association with nonsyndromic EVA. However, these alleles could be pathogenic in trans configuration with a mutant allele in Pendred syndrome.


Subject(s)
Hearing Loss/genetics , Membrane Transport Proteins/genetics , Mutation , Vestibular Aqueduct/metabolism , Adolescent , Adult , Animals , COS Cells , Cell Membrane/metabolism , Child , Child, Preschool , Chlorocebus aethiops , Female , Genetic Variation , Genotype , Hearing Loss/metabolism , Hearing Loss/pathology , Humans , Infant , Male , Membrane Transport Proteins/metabolism , Oocytes/cytology , Oocytes/metabolism , Phenotype , Polymorphism, Genetic , Protein Transport , Sulfate Transporters , Syndrome , Transfection , Vestibular Aqueduct/abnormalities , Xenopus
14.
J Clin Endocrinol Metab ; 93(6): 2383-9, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18349068

ABSTRACT

CONTEXT: McCune-Albright syndrome (MAS) is caused by mutations in GNAS (most often R201C or R201H) leading to constitutive cAMP signaling and multiple endocrine dysfunctions, including morphological and functional thyroid involvement. OBJECTIVE: The objective of the study was to characterize the clinical and molecular features of the MAS-associated thyroid disease in a large cohort of patients. DESIGN: This was a retrospective analysis. SETTING: The study was conducted at the National Institutes of Health Clinical Center. PATIENTS: The study included 100 consecutive MAS patients. INTERVENTIONS: There were no interventions. MAIN OUTCOME MEASURE: Functional and morphological evaluation of the thyroid was measured. Ex vivo experiments were performed on MAS thyroid samples to study the effects of the GNAS mutations on the 5'-deiodinases. Reconstitution experiments in HEK-293 cells were performed to study the effects of GNAS mutations on the type-2 5'-deiodinase. RESULTS: Fifty-four patients had abnormal thyroid ultrasound findings. This group, compared with patients without abnormal findings, had higher T(3) to T(4) ratio, indicating an elevated 5'-deiodinase activity. Thyroid samples from MAS subjects, compared with normal tissue, showed a significant increase in both type 1 (D1) and type 2 (D2) 5'-deiodinase activity (D1 control 5.9 +/- 4.5 vs. MAS 41.7 +/- 26.8 fmol/min.mg, P < 0.001; D2 control 28.3 +/- 13.8 vs. MAS 153.1 +/- 43.7 fmol/min.mg, P < 0.001). Compared with cells transfected with the wild-type R201 allele, the basal transcriptional activity of the D2 promoter was significantly increased in both mutants (C and H) (R 10733 +/- 2855, vs. C 18548 +/- 4514, vs. H 19032 +/- 4410 RLU +/- SD, P < 0.001). CONCLUSION: Thyroid pathology is a common occurrence in MAS. Consistent with the molecular etiology of the disease, the shift in T(3) to T(4) ratio is at least in part secondary to a cAMP-mediated intrathyroidal activation of D2 and to elevated D1 activity.


Subject(s)
Fibrous Dysplasia, Polyostotic/complications , Iodide Peroxidase/physiology , Thyrotoxicosis/etiology , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Cells, Cultured , Child , Child, Preschool , Chromogranins , DNA Mutational Analysis , Female , Fibrous Dysplasia, Polyostotic/enzymology , GTP-Binding Protein alpha Subunits, Gs/genetics , Humans , Infant , Iodide Peroxidase/genetics , Male , Middle Aged , Promoter Regions, Genetic , Retrospective Studies , Thyrotoxicosis/enzymology , Transfection , Triiodothyronine/adverse effects , Iodothyronine Deiodinase Type II
15.
Radiology ; 246(2): 619-29, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18227550

ABSTRACT

PURPOSE: To prospectively evaluate the outcome of patients with acute deep vein thrombosis (DVT) of the lower extremity treated with "lacing" of the thrombus with alteplase (recombinant tissue plasminogen activator, or rTPA). MATERIALS AND METHODS: This HIPAA-compliant study was approved by the Institutional Review Board of the National Heart, Lung, and Blood Institute and was funded by the National Institutes of Health. After giving written consent, 20 patients with first-onset acute DVT were treated with direct intraclot lacing of the thrombus with alteplase (maximum daily dose, 50 mg per leg per day; maximum of four treatments) and full systemic anticoagulation. Alteplase was chosen because its high fibrin affinity obviates continuous infusion of this thrombolytic agent. Ventilation-perfusion (V/Q) scans were performed for evaluation of embolic risks, and clinical and imaging examinations were supplemented with pharmacokinetic studies to enable further assessment of treatment outcomes. RESULTS: The 20 patients included 13 men and seven women aged 18-79 years. Antegrade blood flow was restored throughout the deep venous system in 16 patients (80%) during thrombolytic therapy, with complete resolution of symptoms in 18 patients (90%) after 6 months of anticoagulation. Pharmacokinetic studies showed rapid clearance of circulating alteplase and recovery of plasminogen activator inhibitor-1 levels within 2 hours after termination of alteplase treatment. V/Q scans revealed a 40% incidence of pulmonary embolism before treatment and a 15% incidence of asymptomatic pulmonary embolism during thrombolytic therapy. There were no cases of clinically important pulmonary embolism or serious bleeding during thrombolytic therapy. During a mean follow-up period of 3.4 years, no patient developed a postthrombotic syndrome or recurrent thromboembolism. CONCLUSION: Intraclot injection or lacing of the thrombus with a fibrin-binding thrombolytic agent such as alteplase is an alternative to continuous-infusion thrombolytic regimens and minimizes the duration of systemic exposure to thrombolytic agents.


Subject(s)
Anticoagulants/administration & dosage , Tissue Plasminogen Activator/administration & dosage , Venous Thrombosis/drug therapy , Adolescent , Adult , Aged , Drug Administration Schedule , Drug Therapy, Combination , Female , Fibrinolytic Agents/administration & dosage , Humans , Injections, Intralesional , Male , Middle Aged , Pilot Projects , Treatment Outcome
16.
J Pediatr ; 151(5): 528-31, 531.e1, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17961700

ABSTRACT

OBJECTIVE: To evaluate uterine development of women with Turner syndrome (TS) receiving conventional medical care. STUDY DESIGN: In a cross-sectional study we used ultrasonography for uterine evaluation in 86 women with TS 18 to 45 years of age participating in an intramural NIH study, and who had abnormal karyotypes in >70% of white blood cells. Outcomes were uterine dimensions and shape. Information on hormone treatment was obtained by personal interview. RESULTS: Twenty-five percent had a mature in size and shape uterus, and 31% had an immature uterus, with the remainder in a transitional category. Twenty percent of all participants were not taking hormone replacement therapy (HRT) in the preceding year. The majority on treatment were taking conjugated estrogens (CE) or oral contraceptives (OC). Factors associated with uterine maturity were history of spontaneous puberty and duration and type of HRT, with estradiol-based treatment being the most effective. The age at starting HRT was not a critical factor. CONCLUSIONS: Women with TS may develop a normal uterus even at a late start of HRT given adequate duration of treatment and regardless of karyotype.


Subject(s)
Turner Syndrome/complications , Uterus/anatomy & histology , Adolescent , Adult , Age Factors , Contraceptives, Oral/therapeutic use , Cross-Sectional Studies , Estrogen Replacement Therapy , Estrogens/therapeutic use , Estrogens, Conjugated (USP)/therapeutic use , Female , Humans , Logistic Models , Menarche , Middle Aged , Turner Syndrome/genetics , Ultrasonography , Uterus/diagnostic imaging
17.
J Clin Endocrinol Metab ; 92(6): 2100-6, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17405850

ABSTRACT

CONTEXT: Girls with McCune-Albright syndrome (MAS) and related disorders have gonadotropin-independent precocious puberty due to estrogen secretion from ovarian cysts. Their puberty does not respond to GnRH agonist therapy, and short-acting aromatase inhibitors have had limited effectiveness. OBJECTIVE: Our objective was to assess the effectiveness of the potent, third-generation aromatase inhibitor letrozole in decreasing pubertal progression in girls with MAS and to assess the response of indices of bone turnover associated with the patients' polyostotic fibrous dysplasia. DESIGN: Subjects were evaluated at baseline and every 6 months for 12-36 months while on treatment with letrozole 1.5-2.0 mg/m(2).d. SETTING: This was an open-label therapeutic trial at a single clinical center. PATIENTS: Patients included nine girls aged 3-8 yr with MAS and/or gonadotropin-independent puberty. MAIN OUTCOME MEASURES: Measures included rates of linear growth, bone age advance, mean ovarian volume, estradiol, episodes of vaginal bleeding, and levels of the indices of bone metabolism: serum osteocalcin, alkaline phosphatase, urinary hydroxyproline, pyridinoline, deoxypyridinoline, and N-telopeptides. RESULTS: Girls had decreased rates of growth (P < or = 0.01) and bone age advance (P < or = 0.004) and cessation or slowing in their rates of bleeding over 12-36 months of therapy. Mean ovarian volume, estradiol, and indices of bone metabolism fell after 6 months (P < or = 0.05) but tended to rise by 24-36 months. Uterine volumes did not change. One girl had a ruptured ovarian cyst after 2 yr of treatment. CONCLUSIONS: This preliminary study suggests that letrozole may be effective therapy in some girls with MAS and/or gonadotropin-independent precocious puberty. Possible adverse effects include ovarian enlargement and cyst formation.


Subject(s)
Antineoplastic Agents/administration & dosage , Fibrous Dysplasia, Polyostotic/complications , Nitriles/administration & dosage , Puberty, Precocious/drug therapy , Puberty, Precocious/etiology , Triazoles/administration & dosage , Antineoplastic Agents/adverse effects , Antineoplastic Agents/blood , Biomarkers/blood , Biomarkers/urine , Bone and Bones/metabolism , Child , Child, Preschool , Female , Fibrous Dysplasia, Polyostotic/metabolism , Growth/drug effects , Humans , Letrozole , Male , Menstruation/drug effects , Nitriles/adverse effects , Nitriles/blood , Ovarian Cysts/drug therapy , Ovarian Cysts/etiology , Pilot Projects , Puberty/drug effects , Puberty, Precocious/metabolism , Triazoles/adverse effects , Triazoles/blood
18.
J Pediatr ; 149(3): 412-5, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16939759

ABSTRACT

Generalized vascular tortuosity caused by deficiency of the copper enzyme lysyl oxidase is frequently noted in Menkes disease, but reported examples of peripheral aneurysms are rare. We describe bilateral brachial artery aneurysms in a 10-month-old infant with classical Menkes disease.


Subject(s)
Aneurysm/etiology , Brachial Artery , Menkes Kinky Hair Syndrome/complications , Aneurysm/diagnosis , Aneurysm/surgery , Humans , Infant
19.
Surgery ; 138(6): 1003-8; discussion 1008, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16360384

ABSTRACT

BACKGROUND: Preoperative imaging studies localize insulinomas in less than 50% of patients. Arteriography with calcium stimulation and venous sampling (ASVS) regionalizes greater than 90% of insulinomas but requires specialized expertise and an invasive procedure. This prospective study evaluated laparoscopic exploration with IOUS compared with the other localization procedures in patients with a sporadic insulinoma. METHODS: Between March 2001 and October 2004, 14 patients (7 women and 7 men; mean age, 53) with an insulinoma were enrolled in an IRB-approved protocol. Computed tomography, magnetic resonance imaging, ultrasound scan, and arteriography with calcium stimulation and venous sampling were performed preoperatively. A surgeon, blinded to the results of the localizing studies, performed a laparoscopic exploration with intraoperative ultrasound (IOUS). At the completion of the exploration, the success of laparoscopy for localization was scored, and the tumor was resected. RESULTS: Twelve of 14 tumors were localized successfully before laparoscopy (noninvasive, 7 of 14; invasive, 11 of 14). Laparoscopic IOUS localized successfully 12 of 14 tumors. All lesions were resected, and all patients were cured (median follow-up, 36 months). CONCLUSION: Laparoscopic IOUS identified 86% of tumors. The authors consider laparoscopic IOUS to be equivalent to ASVS in localizing insulinomas. Further study is therefore warranted to determine the role of laparoscopy with IOUS in the localization and treatment algorithm for patients with sporadic insulinoma.


Subject(s)
Insulinoma/diagnostic imaging , Insulinoma/pathology , Laparoscopy/methods , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/pathology , Surgery, Computer-Assisted , Adult , Aged , Anesthesia, General , Female , Follow-Up Studies , Humans , Insulinoma/surgery , Male , Middle Aged , Pancreatectomy , Pancreatic Neoplasms/surgery , Prospective Studies , Single-Blind Method , Ultrasonography
20.
Clin Endocrinol (Oxf) ; 63(1): 73-8, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15963065

ABSTRACT

OBJECTIVE: Ovarian enlargement is a constant feature of syndromes of extreme insulin resistance. The objective of this study is to show the role of insulin on ovarian growth in the presence of low gonadotropin levels. PATIENTS: Seven young patients with syndromes of extreme insulin resistance (five with lipodystrophy, one with Type B syndrome and one with Rabson-Mendenhall syndrome) were studied. MEASUREMENTS: Baseline LH concentrations and luteinizing hormone releasing hormone (LHRH) tests were performed. Total testosterone, insulin and C-peptide values were measured. Pelvic ultrasounds were performed. RESULTS: Four patients were prepubertal (age range 7-10 years old) and had prepubertal gonadotropin levels, and 2 of the 4 who were tested did not respond to LHRH (NIH 10 and RM-PAL). Three patients were Tanner stage 4 (age range 13-17 years old) and had low gonadotropins that did not respond to LHRH stimulation test. All seven patients had marked hyperinsulinaemia and 6 of 7 had at least one enlarged ovary. Testosterone values were increased in 4 of 7 patients. CONCLUSION: This represents the first example of the pathologic role of insulin to stimulate ovarian growth with low circulating gonadotropins. Thus, while ovarian growth and steroidogenesis are normally stimulated by gonadotropins at puberty, hyperinsulinaemia stimulates pathologic growth of the ovary and an androgenic steroid profile that is active at all ages. We suggest that these patients constitute a model to separate the effect of insulin from gonadotropin in stimulating ovarian growth and/or steroidogenesis.


Subject(s)
Gonadotropins/blood , Hyperinsulinism/physiopathology , Insulin Resistance/physiology , Ovary/growth & development , Adolescent , C-Peptide/blood , Child , Female , Gonadotropin-Releasing Hormone/blood , Gonadotropin-Releasing Hormone/physiology , Humans , Hyperinsulinism/blood , Hyperinsulinism/drug therapy , Insulin/blood , Insulin/physiology , Leptin/analogs & derivatives , Leptin/therapeutic use , Lipodystrophy/blood , Lipodystrophy/physiopathology , Luteinizing Hormone/blood , Ovary/diagnostic imaging , Puberty/physiology , Testosterone/blood , Ultrasonography
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