Thyroid Function, Cytokine and IGF-IGFBP Interactions in Cystic Fibrosis Patients

Chesdachai

et al. 2016

Thyroid

Background: Development of goiter and hypothyroidism has been reported in patients with cystic fibrosis (CF) since the 1970s, especially when treated with iodine-based expectorants. With iodine-containing expectorants no longer in routine use, the prevalence of thyroid dysfunction in CF patients is unknown. This cross-sectional study assessed thyroid function status in a large cohort of CF patients. Methods: Sera from ambulatory subjects were obtained from an Institutional Review Board (IRB)-approved biorepository of patients seen at the Emory CF Center between January 1, 2011, and December 31, 2014. Sera from hospitalized subjects were obtained from banked specimens from an IRB-approved inpatient clinical trial. Demographics, forced expiratory volume in one second (FEV1), and medication use were assessed from medical records. Thyroid function tests were measured from the stored sera. Multivariate regression models assessed associations between covariates and thyrotropin (TSH), free thyroxine (fT4), and thyroid dysfunction risk. Results: A total of 89 subjects (54% male, 91% white, M age = 24.4 years, median FEV1 63%) were included in the analyses. One subject was on thyroid hormone replacement, 93% were on pancreatic enzyme replacement, and 68% received antibiotics within six months. None had computed tomography scans with intravenous contrast within six months. One patient had positive thyroid peroxidase (TPO) antibodies. Of the 87 subjects with measured TSH values, seven (8%) had abnormal levels (range 0.2-7.6 lIU/mL; one overt, four subclinical hypothyroidism, and two subclinical hyperthyroidism). Of the 56 subjects with measured fT4 values, 19 (34%) had slightly low levels (range 0.49-0.79 ng/dL; 17 isolated mild hypothyroxinemia). A positive correlation between age and body mass index (BMI; p < 0.001) and a negative correlation between age and FEV1 (p = 0.041) were seen. Age, sex, race/ethnicity, BMI, FEV1, hospitalization status, use of pancreatic enzyme or thyroid hormone replacement, recent antibiotic use, and TPO antibody positivity were not predictive of TSH, fT4, or thyroid dysfunction risk. Stratified analyses by hospitalization did not predict TSH or fT4. Conclusions: Although 24 (27%) of the patients had abnormal serum thyroid function tests, overt thyroid dysfunction was rare in this cohort of 89 patients with CF. The degree of hypothyroxinemia was marginal, likely due to nonthyroidal illness. There were no significant predictors of thyroid dysfunction.

Section: Introductionmentioning

confidence: 81%

Section: Thyroid Function In Cystic Fibrosis 877 Discussionmentioning

confidence: 99%

Thyroid Function in Patients with Cystic Fibrosis: No Longer a Concern?

Chesdachai

et al. 2016

Thyroid

“…A recent study by Volta et al (9) suggested no significant thyroid dysfunction in 17 CF patients compared to age-and sex-matched controls, and they concluded that this may be related to improved nutritional status and lack of iodine including pulmonary expectorant use. The largest study assessing thyroid dysfunction in patients with CF was presented by Sun dose iodine developed goiter, and 83% of those developed hypothyroidism.…”

Section: Discussionmentioning

confidence: 98%

“…An increased incidence of goiter with or without associated hypothyroidism as a complication of receiving pulmonary expectorants containing iodides, low T3 and/or low T 4 and rT 3 levels with increased basal and TRH-stimulated TSH levels, impaired peripheral conversion of T4 to T3 due to selenite deficiency as a result of malnutrition have been reported in particular in patients with CF in previous studies (5)(6)(7)(8). However, unlike previously published studies, normal thyroid function tests in patients with CF compared with normal healthy subjects is available in the literature (9). In present study, we aimed to investigate the prevalence of thyroid dysfunction in children with CF (i) and evaluate general characteristics of these patients in Turkey (ii).…”

Section: Introductionmentioning

confidence: 96%

“…However, unlike previously published studies, normal thyroid function tests in patients with CF compared with normal healthy subjects is available in the literature (9). In present study, we aimed to investigate the prevalence of thyroid dysfunction in children with CF (i) and evaluate general characteristics of these patients in Turkey (ii).…”

Section: Introductionmentioning

confidence: 96%

See 1 more Smart Citation

Thyroid Function Tests in Children with Cystic Fibrosis: Is Thyroid Dysfunction more Common than Estimated in These Patients?

Tuhan¹,

Sözmen²,

Köse³

et al. 2017

Turkish J Pediatr Dis

Objective: Cystic fibrosis (CF) is a life-limiting, multisystemic, autosomal recessive genetic disorder that is characterized by digestive and respiratory dysfunction contributing to growth deficit, chronic respiratory infections, progressive lung tissue damage, and premature death. CF patients have several important endocrine abnormalities including exocrine pancreatic insufficiency, poor linear growth, bone diseases, hypogonadism and thyroid dysfunction. In the present study, we aimed to investigate the prevalence of thyroid dysfunction in children with CF and evaluate the general characteristics of these patients in Turkey. Material and Methods:The study was conducted between January 2015 and June 2015. A total of 42 patients (20 male, 22 female) with CF were included in the study. Demographic information; clinical, laboratory and radiological findings; medication use, and genetic analyses were assessed from the medical records. The serum fT4, fT3 and TSH levels were measured by chemiluminescence immunoassay using a DxI800 autoanalyzer (Beckman Coulter Inc., CA, USA). results: The mean age at the time of diagnosis of CF was 35.5±53.2 (2-194) months in the study population. Eight of the 42 (19%) patients whose TSH, fT4 and fT3 levels were measured had abnormal TSH and fT4 levels (two overt hypothyroidism and six subclinical hypothyroidism). Five (62.5%) of the subjects with thyroid dysfunction were receiving thyroid hormone replacement therapy. conclusion: Our study presents the first evaluation of the patients with CF for thyroid dysfunction in Turkey. In our study population, we detected eight (19 %) CF patients with thyroid dysfunction and five (62.5%) of them were receiving L-thyroxine treatment. In our opinion, regular evaluation of thyroid function tests in patients with CF may be necessary to prevent problems associated with hypothyroidism. Key Words: Children, Cystic fibrosis, L-thyroxine, Thyroid dysfunction ÖzEt Amaç: Kistik fibrozis progresif akciğer hasarı, kronik solunum yolu enfeksiyonları, büyüme geriliği ve erken ölüme neden olan sindirim ve solunum disfonksiyonu ile karakterize multistemik, hayatı kısıtlayan, otozomal resesif genetik bir hastalıktır. Kistik fibrozis ekzokrin panreatik yetmezlik, büyüme geriliği, kemik hastalıkları, hipogonodism ve tiroid hastalıklarını kapsayan bazı önemli endokrin anormalliklere neden olabilmektedir. Bu çalışmada amaç, kistik fibrozisli çocuklarda tiroid disfonksiyonu prevelansını araştırmak ve bu hastaların genel karakteristiklerini belirlemektir. Gereç ve Yöntemler: Çalışma, Ocak 2015-Haziran 2015 tarihleri arasında yapılmıştır. Toplam 42 kistik fibrozisli hasta (20 erkek, 22 kız) çalışmaya alınmıştır. Demografik, klinik, laboratuvar ve radyolojik bulgular, ilaç kullanımı, genetik analizler dosya kayıtlarından elde edilmiştir. Serum fT4, fT3 ve TSH düzeyleri kemilüminesans immunoassay yöntemiyle DxI800 autoanalyzer (Beckman Coulter Inc, CA, USA) kullanılarak ölçülmüştür. bulgular: Çalışma populasyonunda tanı anındaki ortalama yaş 2.9±4.4 (yıl)'di. T...

Hyperthyrotropinemia in newly diagnosed cystic fibrosis patients with pancreatic insufficiency reversed by enzyme therapy

et al. 2018

Mild TSH elevation is a frequent finding in newly diagnosed cystic fibrosis patients with pancreatic insufficiency during infancy. TSH elevation resolves in most cases after initiation of enzyme substitution and improvement of nutritional status without any substitutive therapy with thyroxine. What is Known: • Newly diagnosed infants with cystic fibrosis often present with a state of hyperthyrotropinemia suggesting subclinical hypothyroidism. What is New: • Pancreatic enzyme substitution and improvement of nutrition restores normal TSH levels without the need of thyroxine therapy.