Neonatal outcomes and congenital anomalies in pregnancies affected by hypothyroidism

Probiotics and Prebiotics in Subclinical Hypothyroidism of Pregnancy with Small Intestinal Bacterial Overgrowth

Evaluating efficacy of probiotics combined with prebiotics in small intestinal bacterial overgrowth (SIBO) in subclinical hypothyroidism (SCH) in the second trimester. We collected data from 78 pregnant women with SCH (SCH group) and 74 normal pregnant women (control group) in second trimester, compare the differences in high sensitivity C-reactive protein (hsCRP), result of lactulose methane-hydrogen breath test and gastrointestinal symptoms assessed by GSRS scale between two groups. In SCH group, 32 patients with SIBO were selected as intervention group. Treatment with probiotics + prebiotics for 21 days; The differences of lipid metabolism, hsCRP, thyroid function level, methane-hydrogen breath test results and GSRS scores before and after treatment were compared to evaluate the therapeutic effect. (1) The positive rate of SIBO and methane, hsCRP levels in SCH group were higher than those in control group (P < 0.05), the total score of GSRS scale, mean score of indigestion syndrome, and constipation syndrome in SCH group were higher (P < 0.05). (2) The mean abundance of hydrogen and methane were higher in SCH group. (3) After treatment, serum levels of thyrotropin(TSH), total cholesterol(TC), triglyceride(TG), low-density lipoprotein (LDL), and hsCRP in intervention group were decreased, and high-density lipoprotein (HDL) was increased compared with before treatment (P < 0.05). (4) After treatment, methane positive rate, total score of GSRS scale, mean score of diarrhea syndrome, dyspepsia syndrome, and constipation syndrome were decreased (P < 0.05). (5) The average abundance of methane and hydrogen were lower. Probiotics combined with prebiotics are effective in the treatment of SIBO in pregnant SCH patients.Clinical Trial Registration Number: ChiCTR1900026326.

Fetal cardiac left ventricle functional changes in pregnancies with maternal hypothyroidism

OBJECTIVES

To evaluate fetal cardiac function in cases with overt and subclinical hypothyroidism and to determine the effect of levothyroxine (LT4) treatment and Anti-thyroid peroxidase (Anti-TPO) antibody status on fetal cardiac functions in cases with subclinical hypothyroidism.

METHODS

Within the scope of the study, fetuses of 23 overt hypothyroid, 52 subclinical hypothyroid and 250 control group pregnant women were evaluated. Fetal cardiac function was assessed via cardiac Doppler.

RESULTS

Isovolumetric relaxation time (IRT) and myocardial performance index (MPI) values in the overt hypothyroid group were significantly higher than both the subclinical hypothyroid group (p: .006, p: .000, respectively) and the control group (p: .000, p: .000, respectively). In addition, both IRT and MPI were significantly higher in the subclinical hypothyroid group than in the control group (p: .000, p: .000, respectively). In the subclinical hypothyroid group, there was no significant difference in terms of cardiac function parameters in the fetuses of pregnant women who received LT4 therapy and those who did not. When pregnant women with subclinical hypothyroidism were evaluated according to their Anti-TPO antibody status, IRT and MPI values were found to be significantly higher in fetuses of Anti-TPO (+) pregnant women (respectively, p: .005, p: .019).

CONCLUSION

In the presence of maternal overt or subclinical hypothyroidism, fetal cardiac functions may be affected as early as the second trimester. Anti-TPO antibody positivity in cases with subclinical hypothyroidism seems to negatively affect fetal cardiac functions.

Streptococcus gallolyticus Subspecies pasteurianus Meningitis in an Infant with Hypothyroidism and Diarrhea

Streptococcus gallolyticus subspecies pasteurianus, formerly classified as S. bovis biotype II/2 until 2003, is a rare cause of infant meningitis. Over the past 2 decades, only a few individual case reports and limited case series exist in the English-language literature. Moreover, the pathogenesis of S. gallolyticus subsp. pasteurianus meningitis in infants is unclear. Here we report a case of meningitis in a 6-week-old infant with hypothyroidism and preceding diarrhea. In this case, S. gallolyticus was cultured from cerebrospinal fluid, and then S. gallolyticus subspecies pasteurianus was identified by metagenomic next-generation Sequencing. The infant recovered uneventfully after a 4-week antibiotic course with ceftriaxone and vancomycin. Then combined with the literature of S. gallolyticus subsp. pasteurianus meningitis in infants, we discuss the possible etiology.

Global prevalence of congenital hypothyroidism among neonates from 1969 to 2020: a systematic review and meta-analysis

Little is known about the global prevalence of congenital hypothyroidism (CH), though it is known to vary across countries and time periods. This meta-analysis aims to estimate the global and regional prevalence of CH among births between 1969 and 2020. PubMed, Web of Sciences, and Embase databases were searched for relevant studies between January 1, 1975, and March 2, 2020. Pooled prevalence was calculated using a generalized linear mixed model, and expressed as a rate per 10,000 neonates. The meta-analysis involved 116 studies, which analyzed 330,210,785 neonates, among whom 174,543 were diagnosed with CH. The pooled global prevalence of CH from 1969 to 2020 was 4.25 (95% confidence interval (CI) 3.96-4.57). The geographic region with highest prevalence was the Eastern Mediterranean (7.91, 95% CI 6.09-10.26), where the prevalence was 2.48-fold (95% CI 2.04-3.01) that in Europe. The national income level with the highest prevalence was upper-middle (6.76, 95% CI 5.66-8.06), which was 1.91-fold (95% CI 1.65-2.22) that in high-income countries. Global prevalence of CH was 52% (95% CI 4-122%) higher in 2011-2020 than in 1969-1980, after adjusting for geographic region, national income level, and screening strategy.  Conclusion: The global prevalence of CH increased from 1969 to 2020, which may reflect the implementation of national neonatal screening, neonatal testing for thyroid-stimulating hormone, and a lowering of the diagnostic level of this hormone. Additional factors are likely to be driving the increase, which should be identified in future research. What is Known: • Cumulated evidence had suggested that the occurrences of congenital hypothyroidism (CH) among newborns were varied in different countries.. • Up-trends of the birth prevalence of CH were observed in many European and American countries. What is New: • This is the first meta-analysis to estimate global and regional prevalence of CH among newborns. • The global prevalence of CH has increased by 127% since 1969. The Eastern Mediterranean has the highest prevalence and stands out with the most pronounced escalation in the prevalence of CH.

A Narrative Review on the Effect of Maternal Hypothyroidism on Fetal Development

The thyroid is a butterfly-shaped gland located in the human body's neck region. The thyroid produces three hormones that are essential for regulating body temperature, energy production, weight, hair and nail growth, and menstrual cycle maintenance. The production of these hormones is controlled by a feedback mechanism. Various factors cause changes in the stimulation and inhibition of these hormones, which ultimately causes either excessive release or a decrease in the levels of thyroid hormones. These causes can be physiological or pathological. One of the physiological causes is pregnancy. Pregnancy is a very complex process in which many changes occur in the body and its functioning. One of which is changes in the maternal thyroid gland. The inability to adequately adapt to the changes leads to the abnormal functioning of the thyroid gland. During pregnancy, there is a variation in the concentration of thyroid hormones which may cause a decrease in levels or inhibition in the production of thyroid hormones. This condition is called hypothyroidism. Hypothyroidism in pregnant mothers can either be gestational or may be a condition that is present way before her pregnancy. Often, gestational hypothyroidism reverts after delivery during the postpartum period but can also be present as subclinical hypothyroidism. In such cases, they pose a significant threat to development, cause growth hindrance to the infant in the womb, and cause abnormalities in the offspring in the future. Some of the changes occur in the gland because of enhancement in levels of thyroid binding globulin, increased clearance rate of iodine from the body in kidneys, altered effects in human chorionic gonadotropin hormone, and decreased consumption of iodine in meals. Iodine disbalance in maternal hypothyroidism is associated with severe health issues like cretinism and mental retardation. Thyroid hormones are crucial for the infant's neural, cognitive, and intelligence quotient development in the womb. Thus, the disturbances in the maternal hormone levels disturb typical early developmental characteristics. In the world of rapidly advancing scientific research, there are many ways in which this condition can be detected early, diagnosed correctly, and given apt and required attention and treatment for causing the least harm to the fetus and the mother.

Serological Characteristics, Etiological Analysis, and Treatment Prognosis of Children with Congenital Hypothyroidism

Objective

The aim of the study is to analyze the serological features, etiology, and prognosis of congenital hypothyroidism (CH) treated with L-thyroxine sodium (L-T4).

Methods

A total of 126 CH children in our hospital from June 2015 to January 2020 were selected as the research objects, and L-T4 treatment was given immediately after diagnosis. After diagnosis and 24 months of treatment, laboratory serum thyroid function-related indicators were examined, and thyroid changes were determined by ultrasound. We compared serum thyroxine levels in children with different thyroid changes, compared serum thyroid hormone levels, serum ghrelin levels, and body mass index (BMI) changes in children with CH before treatment and after 24 months of treatment, and analyzed the prognosis of treatment in children. In terms of thyroid changes in 126 CH children, 32 cases (25.40%) had a normal thyroid gland, 16 cases (12.70%) had a hypoplastic thyroid gland, 40 cases (31.75%) had an ectopic thyroid gland, 28 cases (22.22%) had an absent thyroid gland, and 10 cases (7.93%) had an enlarged thyroid gland, with an ectopic thyroid gland being the most common. In terms of serological expression of CH children, the TSH level in children with thyroid dysplasia was significantly higher than that in children with basic normal and T3 and T4 levels were significantly lower than those in children with basic normal (P < 0.05). At the same time, the TSH level in children with thyroid absence, ectopic, and enlargement was increased, while thyroxine (T4) and tri-iodothyronine (T3) levels were decreased compared with those in children with thyroid dysplasia. The difference was statistically significant (P < 0.05). Univariate analysis showed that there were statistically significant differences in birth weight, week of gestation at delivery, maternal age at childbirth, household registration, and a family history of thyroid disease compared between the two groups (P < 0.05); multivariate logistic regression analysis showed that birth weight <2,500 g, maternal age >35 years, rural residence, and a family history of thyroid disease were risk factors for neonatal CH (P < 0.05). Serum thyroid-stimulating hormone (TSH) levels, serum ghrelin levels, and the body mass index of children with CH decreased significantly, and T4 levels increased significantly after 24 months of treatment (P < 0.05).

Conclusion

Screening for common causes of CH is conducive to timely detection of children with CH, and L-T4 treatment can effectively improve thyroid function in children.

Congenital Hypothyroidism in Preterm Newborns - The Challenges of Diagnostics and Treatment: A Review

Preterm newborns are forced to adapt to harsh extrauterine conditions and endure numerous adversities despite their incomplete growth and maturity. The inadequate thyroid hormones secretion as well as the impaired regulation of hypothalamus-pituitary-thyroid axis may lead to hypothyroxinemia. Two first weeks after birth are pivotal for brain neurons development, synaptogenesis and gliogenesis. The decreased level of thyroxine regardless of cause may lead to delayed mental development. Congenital hypothyroidism (CH) is a disorder highly prevalent in premature neonates and it originates from maternal factors, perinatal and labor complications, genetic abnormalities, thyroid malformations as well as side effects of medications and therapeutic actions. Because of that, the prevention is not fully attainable. CH manifests clinically in a few distinctive forms: primary, permanent or transient, and secondary. Their etiologies and implications bear little resemblance. Therefore, the exact diagnosis and differentiation between the subtypes of CH are crucial in order to plan an effective treatment. Hypothyroxinemia of prematurity indicates dynamic changes in thyroid hormone levels dependent on neonatal postmenstrual age, which directly affects patient's maintenance and wellbeing. The basis of a successful treatment relies on an early and accurate diagnosis. Neonatal screening is a recommended method of detecting CH in preterm newborns. The preferred approach involves testing serum TSH and fT4 concentrations and assessing their levels according to the cut-off values. The possible benefits also include the evaluation of CH subtype. Nevertheless, the reference range of thyroid hormones varies all around the world and impedes the introduction of universal testing recommendations. Unification of the methodology in neonatal screening would be advantageous for prevention and management of CH. Current guidelines recommend levothyroxine treatment of CH in preterm infants only when the diagnose is confirmed. Moreover, they underline the importance of the re-evaluation among preterm born infants due to the frequency of transient forms of hypothyroidism. However, results from multiple clinical trials are mixed and depend on the newborn's gestational age at birth. Some benefits of treatment are seen especially in the preterm infants born <29 weeks' gestation. The discrepancies among trials and guidelines create an urgent need to conduct more large sample size studies that could provide further analyses and consensus. This review summarizes the current state of knowledge on congenital hypothyroidism in preterm infants. We discuss screening and treatment options and demonstrate present challenges and controversies.

Quantifying the Impacts of Pre- and Post-Conception TSH Levels on Birth Outcomes: An Examination of Different Machine Learning Models

BACKGROUND

While previous studies identified risk factors for diverse pregnancy outcomes, traditional statistical methods had limited ability to quantify their impacts on birth outcomes precisely. We aimed to use a novel approach that applied different machine learning models to not only predict birth outcomes but systematically quantify the impacts of pre- and post-conception serum thyroid-stimulating hormone (TSH) levels and other predictive characteristics on birth outcomes.

METHODS

We used data from women who gave birth in Shanghai First Maternal and Infant Hospital from 2014 to 2015. We included 14,110 women with the measurement of preconception TSH in the first analysis and 3,428 out of 14,110 women with both pre- and post-conception TSH measurement in the second analysis. Synthetic Minority Over-sampling Technique (SMOTE) was applied to adjust the imbalance of outcomes. We randomly split (7:3) the data into a training set and a test set in both analyses. We compared Area Under Curve (AUC) for dichotomous outcomes and macro F1 score for categorical outcomes among four machine learning models, including logistic model, random forest model, XGBoost model, and multilayer neural network models to assess model performance. The model with the highest AUC or macro F1 score was used to quantify the importance of predictive features for adverse birth outcomes with the loss function algorithm.

RESULTS

The XGBoost model provided prominent advantages in terms of improved performance and prediction of polytomous variables. Predictive models with abnormal preconception TSH or not-well-controlled TSH, a novel indicator with pre- and post-conception TSH levels combined, provided the similar robust prediction for birth outcomes. The highest AUC of 98.7% happened in XGBoost model for predicting low Apgar score with not-well-controlled TSH adjusted. By loss function algorithm, we found that not-well-controlled TSH ranked 4^th, 6^th, and 7^th among 14 features, respectively, in predicting birthweight, induction, and preterm birth, and 3^rd among 19 features in predicting low Apgar score.

CONCLUSIONS

Our four machine learning models offered valid predictions of birth outcomes in women during pre- and post-conception. The predictive features panel suggested the combined TSH indicator (not-well-controlled TSH) could be a potentially competitive biomarker to predict adverse birth outcomes.