RESUMO
OBJECTIVES: To describe the response of thyroid-stimulating hormone (TSH) to thyroid-releasing hormone in children and adolescents with Prader-Willi syndrome (PWS), and to compare TSH and total thyroxine (TT4) concentrations measured on neonatal screening for congenital hypothyroidism in children with PWS and controls. STUDY DESIGN: All participants had genetically confirmed PWS. The TSH responses to thyroid-releasing hormone, free thyroxine (fT4), and free triiodothyronine (fT3) were measured in 21 subjects (14 females and 7 males; mean age, 6.4 years). Capillary TT4 was measured on neonatal screening samples from 23 subjects with PWS (14 females and 9 males), each of whom was matched for birth weight and sex with 4 anonymized controls. RESULTS: One subject with PWS had tertiary hypothyroidism. TSH level increased from 1.37 mU/L at baseline to 39.6 mU/L at 20 minutes, 47.2 mU/L at 40 minutes, 44.5 mU/L at 60 minutes, and 47.2 mU/L at 120 minutes. fT4 concentration was 6.3 pmol/L, and fT3 concentration was 4.6 pmol/L. In the other 20 subjects, mean TSH level was 1.9 mU/L (range, 0.8-4.2 mU/L) at baseline and 21.8 mU/L (range, 10.0-46.7 mU/L) at 20 minutes (peak). Mean fT4 concentration (10.4 pmol/L; range, 8.2-13.5 pmol/L) was in the lower one-third of the normal range in 18 subjects, and mean fT3 concentration (6.1 pmol/L; range, 4.8-8.4 pmol/L) was above the median in 13 subjects. In neonates, mean TSH level was 3.1 mU/L (range, 0.4-10.0 mU/L) in subjects with PWS versus 3.3 mU/L (range, 0.0-7.0 mU/L) in controls, and mean TT4 in subjects with PWS was 111% (range, 17%-203%) that of controls (P = not significant). CONCLUSION: Thyroid function was normal in our newborn subjects. In older children, frank hypothyroidism was found in only 1 of our 21 subjects. Thus, levothyroxine treatment should not be routinely prescribed to youth with PWS.
Assuntos
Hipotireoidismo/etiologia , Síndrome de Prader-Willi/complicações , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Adolescente , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Síndrome de Prader-Willi/sangue , Síndrome de Prader-Willi/diagnósticoRESUMO
OBJECTIVES: To determine which biological or clinical variables may predict cortisol response to low-dose adrenocorticotropic hormone (ACTH) stimulation following supraphysiological doses of glucocorticoids in children. STUDY DESIGN: This retrospective study included all patients who underwent ACTH testing (1 µg) between October 2008 and June 2010 at the Sainte-Justine University Hospital Center, Montreal, after supraphysiological doses of glucocorticoids. RESULTS: Data from 103 patients (median age, 8.0 years; range, 0.6-18.5 years; 57 girls) were analyzed, revealing growth deceleration in 37% and excessive weight gain in 33%. Reasons for glucocorticoid treatment included asthma (n = 30) and hematologic (n = 22), dermatologic (n = 19), rheumatologic (n = 16), and miscellaneous (n = 16) disorders. The following information was recorded: duration of glucocorticoid treatment (median, 374 days; range, 5-4226 days); duration of physiological hydrocortisone replacement (median, 118 days; range, 0-1089 days); maximum daily (median, 200 mg/m(2)/day; range, 12-3750 mg/m(2)/day) and cumulative (median, 16â728 mg/m(2); range, 82-178â209 mg/m(2)) doses, in hydrocortisone equivalents; and interval since the last dose (median, 43 days; range, 1-1584 days). Sixty-two patients (58%) exhibited a normal response (ie, peak cortisol >500 nmol/L) to ACTH stimulation. Peak cortisol level was not related to sex, prior morning cortisol level, duration of treatment, or cumulative glucocorticoid dose; 28% of the patients with normal baseline cortisol levels nevertheless demonstrated a subnormal response to ACTH. CONCLUSION: Given the absence of clinical or biological predictors of the cortisol response to ACTH after suppressive doses of glucocorticoids, physicians have only 2 options: (1) empirically advocate glucocorticoid stress coverage during 18 months after cessation of high-dose glucocorticoid treatment; or (2) perform serial ACTH testing in all such patients until a normal peak cortisol level is attained.
Assuntos
Hormônio Adrenocorticotrópico/administração & dosagem , Dexametasona/administração & dosagem , Glucocorticoides/administração & dosagem , Hidrocortisona/administração & dosagem , Hidrocortisona/sangue , Prednisona/administração & dosagem , Adolescente , Hormônio Adrenocorticotrópico/farmacologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos RetrospectivosRESUMO
OBJECTIVES: To search for evidence of acute adrenal failure linked to inappropriate use of stress management protocols. STUDY DESIGN: Patients followed up for primary adrenal insufficiency (n = 102) or secondary adrenal insufficiency (n = 34) between 1973 and 2007 were included. All hospitalizations, both urgent (n = 157) and elective (n = 90), were examined. We recorded clinical evidence of acute adrenal failure, parental management before admission, and details of glucocorticoid prescription and administration in the hospital setting. RESULTS: For urgent hospitalizations, subgroup and time period did not influence the percentage of patients hospitalized (primary adrenal insufficiency 45%; secondary adrenal insufficiency 38%; P = .55). The use of stress glucocorticoid doses by parents increased significantly after 1997 (P < .05), although still only 47% increased glucocorticoids before hospitalization. Stress doses were more frequently administered on arrival in our emergency department after 1990 (P < .05); patients with signs or symptoms of acute adrenal failure decreased to 27% after 1997 (P < .01). Twenty-four percent of all hospitalizations were marked by suboptimal adherence to glucocorticoid stress protocols, with rare but significant clinical consequences. CONCLUSIONS: In spite of an increased use of glucocorticoid stress dose protocols by parents and physicians, patients remain at risk of morbidity and death from acute adrenal failure. This risk may be minimized with conscientious application of stress protocols, but other patient-specific risk factors may also be implicated.
Assuntos
Insuficiência Adrenal/tratamento farmacológico , Glucocorticoides/administração & dosagem , Fidelidade a Diretrizes , Terapia de Reposição Hormonal/métodos , Auditoria Médica , Estresse Fisiológico , Adolescente , Criança , Pré-Escolar , Feminino , Hospitalização , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Masculino , Quebeque , Estudos RetrospectivosRESUMO
Hypothyroidism was documented by cordocentesis at 19 weeks in a fetus with non-immune goiter. Intra-amniotic thyroxine was injected at 25 weeks when amniotic fluid volume increased. Psychomotor outcome was normal. We argue that intra-amniotic thyroxine should not be used to treat the hypothyroidism but only to correct the development of polyhydramnios.
Assuntos
Hipotireoidismo Congênito/terapia , Doenças Fetais/terapia , Bócio/congênito , Tiroxina/administração & dosagem , Adulto , Líquido Amniótico , Hipotireoidismo Congênito/diagnóstico por imagem , Cordocentese , Feminino , Doenças Fetais/diagnóstico por imagem , Bócio/diagnóstico por imagem , Humanos , Masculino , Poli-Hidrâmnios/prevenção & controle , Gravidez , Segundo Trimestre da Gravidez , Tireotropina/sangue , Ultrassonografia Pré-NatalRESUMO
A term infant was born with respiratory distress, and subsequent imaging, histopathologic, and hormonal studies confirmed congenital hypothyroidism. This report is intended to alert pediatricians to the possibility of congenital hypothyroidism as a cause of respiratory symptoms of unknown cause in neonates with respiratory distress.
Assuntos
Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/diagnóstico , Doenças Pulmonares Intersticiais/etiologia , Insuficiência Respiratória/etiologia , Hipotireoidismo Congênito/terapia , Humanos , Recém-Nascido , Doenças Pulmonares Intersticiais/patologia , Doenças Pulmonares Intersticiais/terapia , Masculino , Insuficiência Respiratória/patologia , Insuficiência Respiratória/terapiaRESUMO
We identified five patients with congenital secondary hypothyroidism with isolated thyrotropin (TSH) deficiency originating from three and two unrelated Argentinean and Swiss families, respectively. The affected patients presented with both low TSH as well as low thyroid hormone levels. Further, TSH-releasing hormone (TRH) stimulation failed to increase serum TSH, whereas prolactin increased adequately. These affected children were homozygous for a 1-bp deletion (822delT) in the TSH-beta subunit gene leading to a cysteine 105 to valine conversion (C105V) and to a frameshift with a premature stop codon at position 114 (C105Vfs114X). In a total of 22 families five different mutations located within the coding region of the TSH-beta subunit gene responsible for congenital secondary hypothyroidism have been reported so far (E12X; G29R; Q49X; IVS2 +5, G --> A; C105Vfs114X). Importantly, out of 13 families, including our five families, the C105Vfs114X mutation has been described in 12 unrelated and non-consanguineous families, whereas the remaining four TSH-beta subunit gene mutations have been described in consanguineous families only. Therefore the C105Vfs114X mutation within the TSH-beta subunit gene is the most frequent alteration causing congenital secondary hypothyroidism (13 of 22; 59%) and occurs mainly in unrelated and non-consanguineous families (12 of 13; 92%). As we could exclude a common ancestry by microsatellite marker analysis in our five independent families we concluded that the codon 105 in the TSH-beta subunit gene might be a "hot spot," although a founder effect has been reported in certain cases clustered in a highly specific and restricted geographical area.