Introduction: The thyroid-kidney axis represents a clinically significant bidirectional relationship. Nephrotic syndrome (NS) may induce hypothyroidism via urinary hormonal and binding protein losses, while severe hypothyroidism may mimic NS and contribute to renal dysfunction. Cases: A 64-year-old male with gout, presented with facial puffiness, pedal edema, weight gain and frothy urine. Investigations revealed severe hypothyroidism FT4 <0.5 pmol/L (12–22 pmol/L) TSH 314 mIU/L (0.27–4.2 mIU/L) with NS – UPCR 7.7 3 g/L (0.04–0.15 g/L), albumin 22 g/L, total cholesterol 15.9 mmol/L – and renal impairment (eGFR 58 mL/min/1.73 m²). Positive anti-TPO antibodies suggested Hashimoto’s thyroiditis. He was initiated on liothyronine, hydrocortisone, levothyroxine and diuretics. Although FT4 normalized (14.4 pmol/L) a month later, renal function worsened requiring dialysis. Further evaluation including renal biopsy demonstrated IgA nephropathy as the underlying cause of NS and renal failure. Treatment with prednisolone led to gradual improvement in renal function and proteinuria (UPCR 0.21 g/L). A 73-year-old male with hypothyroidism diagnosed 6 months prior (FT4 11.9 pmol/L, TSH 7.23 mIU/L) for thyroxine replacement, diabetes, hypertension, dyslipidemia and CKD presented with anasarca, decompensated heart failure, pleural and pericardial effusions requiring ventilatory and inotropic support. On admission, he had marked hypothyroidism (FT4 2.9 pmol/L and TSH 97.2 mIU/L) and moderate proteinuria (UPCR 0.81 g/L). He was similarly treated with liothyronine, hydrocortisone and levothyroxine. Renal function initially deteriorated (creatinine 439 µmol/L, eGFR 11 mL/min/1.73 m²) but later returned to baseline with clinical recovery. Despite normalization of FT4 months later, proteinuria persisted; but renal function remained stable. Conclusion These cases highlight the overlapping manifestations of severe hypothyroidism and renal dysfunction with proteinuria. Each may mimic or exacerbate the other. NS may unmask underlying hypothyroidism. While inadequately treated hypothyroidism can worsen proteinuric CKD exacerbating hypothyroidism. Concurrent evaluation of both systems is essential to prevent misdiagnosis and guide timely management.
Hypothyroidism ; Proteinuria ; Kidney

Introduction: Langerhans cell histiocytosis (LCH) is a clonal proliferative disorder of langerin-positive histiocytes. Endocrine involvement most frequently manifests as central diabetes insipidus or secondary hypothyroidism, caused by infiltration of the hypothalamic-pituitary axis. Conversely, direct infiltration of the thyroid gland leading to primary hypothyroidism is an exceptionally rare clinical entity, particularly when presenting concurrently with central disease. Case: A 21-year-old female with known right otic and multisystem LCH presented with septic shock secondary to a right ear abscess accompanied by polyuria and polydipsia. Physical examination revealed a palpable goiter. Clinical and biochemical evaluation confirmed central diabetes insipidus with associated anterior hypopituitarism (low adrenocorticotropic hormone, follicle-stimulating hormone, and luteinizing hormone). However, concurrent thyroid function tests demonstrated overt primary hypothyroidism, evidenced by an appropriately elevated thyroid-stimulating hormone (26.19 mIU/L) and low free T4 (5.47 pmol/L), rather than the anticipated secondary hypothyroidism. Neck ultrasound showed diffuse thyroid enlargement with heterogeneous echotexture. Crucially, anti-thyroid peroxidase and anti-thyroglobulin antibodies were both negative, rendering Hashimoto’s thyroiditis highly unlikely. Although the patient declined confirmatory fine-needle aspiration, the constellation of a palpable goiter, characteristic ultrasonographic findings, negative autoimmunity, and active multisystem disease strongly supported a diagnosis of direct histiocytic infiltration of the thyroid gland. She was initiated on appropriate glucocorticoid coverage and subsequent levothyroxine replacement, alongside systemic intravenous cytarabine. Conclusion This case highlights a rare, mixed endocrine profile in multisystem LCH, demonstrating that pituitary and direct end-organ infiltration can coexist. Hypothyroidism in LCH patients with established central diabetes insipidus should not be reflexively assumed to be central in origin. A comprehensive diagnostic workup, including autoantibody screening, ultrasound, and ideally histopathological confirmation, is essential to accurately identify primary endocrine failure and guide appropriate clinical management in these complex cases.
Histiocytosis, Langerhans-Cell ; Hypothyroidism ; Pituitary Gland

Introduction: Macro-thyroid-stimulating hormone (macro-TSH) is a rare complex formed by monomeric TSH with anti-TSH autoantibodies. Macromolecules of TSH are not renally excreted due to its large size, leading to elevated TSH measurements without clinical consequences. This rare condition frequently mimics subclinical hypothyroidism, often leading to misdiagnosis and inappropriate levothyroxine therapy. Case: A 17-year-old female with major depressive disorder was biochemically diagnosed with subclinical hypothyroidism (TSH 39.06 mIU/L, free thyroxine 4 12.9 pmol/L, antithyroid peroxidase negative) and commenced on levothyroxine. Over 5 years, her TSH levels heavily fluctuated (0.48–82.59 mIU/L) and remained persistently elevated with high-normal free T4 levels despite treatment adherence. An endocrinology consult was obtained, and clinical evaluation revealed a clinically asymptomatic and euthyroid patient, with no family history of thyroid disease or supplement use, and there was no goiter. Assay interference was excluded by analyzing her thyroid function tests on a different platform, which yielded similar biochemical results. Subsequently, a polyethylene glycol (PEG) precipitation test was performed. Her pre-PEG TSH of 29.24 mIU/L decreased significantly to 2.78 mIU/L post-PEG. This yielded a remarkably low TSH recovery rate of 9.5%, strongly indicating the presence of macroTSH. Levothyroxine was then stopped, and she remained clinically euthyroid. Conclusion While gel filtration chromatography remains the gold standard for diagnosing this condition, PEG precipitation is a more accessible, cost-effective, and reliable screening method in clinical practice. A TSH recovery rate below 20% is considered highly suggestive of macro-TSH. Clinicians should maintain a high index of suspicion for macro-TSH in asymptomatic patients presenting with isolated TSH elevations that do not respond to thyroxine therapy. Prompt recognition prevents misdiagnosis and avoids the potential risks of unnecessary thyroid hormone replacement.
Hypothyroidism ; Thyrotropin

Introduction: Cranial nerve palsies have been reported in patients with uncontrolled hypothyroidism. We describe a case of overt hypothyroidism due to treatment disruption following radioiodine therapy, presented with a unilateral lower motor neuron seventh cranial nerve palsy. Case: A 32-year-old female presented with hypertension, dyslipidemia, class III obesity, and Graves’ disease post radioiodine therapy. She had stable thyroid function test with levothyroxine replacement post radioiodine. She presented with a 3-day history of right-sided facial droop associated with lethargy, weight gain, and constipation. She reported inadequate levothyroxine supply due to 2-month lapses in follow-up. On examination, there was a right-sided lower motor neuron 7th cranial nerve palsy with delayed ankle reflexes. No additional neurological deficits, goiter, cutaneous rashes, or vesicular lesions were noted. There was no preceding viral illness or otologic symptoms. Thyroid function tests showed overt hypothyroidism with thyroid-stimulating hormone 38 mIU/L, free thyroxine <5.4 pmol/L with a deranged lipid profile (total cholesterol: 8.8 mmol/L, low-density lipoprotein: 5.72 mmol/L, triglyceride: 1.77 mmol/L). Renal and liver function tests were within normal limits, with no leukocytosis. Neuroimaging of the brain was unremarkable. She was commenced on a short course of high-dose prednisolone, with no improvement in symptoms. Levothyroxine replacement therapy initiated led to progressive restoration of thyroid function, accompanied by symptom recovery. Conclusion Isolated lower motor 7th nerve palsy has been reported as a manifestation of hypothyroidism. This case underscores the importance of early recognition to enable timely and appropriate management, as patients with hypothyroidisminduced isolated seventh nerve palsy demonstrate marked recovery with adequate levothyroxine replacement.
Facial Nerve ; Hypothyroidism ; Motor Neurons ; Paralysis

Introduction: Autoimmune thyroid disease can follow a triphasic course: thyrotoxicosis, a transient euthyroid period, and eventual hypothyroidism, and may coexist with myelodysplastic syndrome (MDS) in the context of immune dysregulation. Case: We describe a 35-year-old male with MDS (multilineage dysplasia) receiving cyclosporine who initially presented with painless thyrotoxicosis, with suppressed thyroidstimulating hormone (TSH) and elevated free thyroxine (FT4). During this hyperthyroid phase, thyrotropin receptor antibody (TRAb) was positive. Over time, his thyroid status fluctuated, progressing to overt hypothyroidism, and he had poor adherence to thyroid medications. On admission, he had prominent hypothyroid features (fatigue, cold intolerance, slowed movement, periorbital puffiness) with severe biochemical hypothyroidism (TSH 49.5 µIU/mL; FT4 0.419 ng/dL). Anti-thyroid peroxidase (anti-TPO) antibodies 12.62 IU/mL (negative <5.61 IU/mL; positive ≥5.61 IU/mL) showed an autoimmune response to the thyroid. Thyroid ultrasound showed heterogeneous, hyperechoic with some hypoechoic parts, and no significant increase in thyroid vascularity was observed, supporting autoimmune thyroiditis representation. His hematologic profile remained consistent with MDS, with chronic macrocytic anemia and thrombocytopenia. Conclusion This case highlights a dynamic autoimmune thyroiditis phenotype progressing from a hyperthyroid phase with TRAb positivity to higher anti-TPO overt hypothyroidism in a patient with MDS. In individuals with MDS and changing thyroid function tests, clinicians should keep autoimmune thyroiditis variants in mind and use thyroid antibodies together with ultrasound to secure the diagnosis when the clinical pattern is typical.
Myelodysplastic Syndromes ; Thyroiditis, Autoimmune ; Hypothyroidism ; Thyrotoxicosis

BACKGROUND AND OBJECTIVE

Transient congenital hypothyroidism (TCH) refers to temporary deficiency of thyroid hormone identified after birth which later recovers to improved thyroxine production. Its prevalence in the Philippines has not been reported in a large-scale study. Its diagnosis remains difficult due to its numerous possible etiologies. Identifying the predictive factors of TCH may aid in earlier diagnosis and decreased risk of overtreatment. This study aimed to determine the predictive factors for TCH in children with congenital hypothyroidism (CH) detected by newborn screening (NBS) in the Philippines from January 2010 to December 2017.

In this multicenter retrospective cohort study involving 15 NBS continuity clinics in the Philippines, medical records were reviewed, and clinical and laboratory factors were compared between children with TCH and those with permanent congenital hypothyroidism (PCH). Of the 2,913 children diagnosed with CH in the Philippines from 2010 to 2017, 1,163 (39.92%) were excluded from the study due to an unrecalled or lost to follow-up status, or a concomitant diagnosis of Down Syndrome.

Among the 1,750 patients included in analysis, 6.97% were diagnosed with TCH, 60.80% were female, mean gestational age at birth was 38 weeks, and mean birth weight was 2,841 grams. Confirmatory thyrotropin (TSH) was lower and confirmatory free thyroxine (FT4) was higher in the TCH group compared to those with PCH (TSH 32.80 vs 86.65 µIU/mL [p < 0.0001]; FT4 9.90 vs 7.37 pmol/L [p 0.001]). The TCH group required lower L-thyroxine doses compared to the PCH group at treatment initiation and at 1, 2, and 3 years of age (initial 6.98 vs 12.08 µg/ kg/day [p < 0.0001]; at 1 year 1.89 vs 4.11 µg/kg/day [p < 0.0001]; at 2 years 1.21 vs 3.72 µg/kg/day [p < 0.0001]; at 3 years 0.83 vs 3.45 µg/kg/day [p < 0.0001]). Among those with TCH, mean serum TSH decreased significantly after treatment with L-thyroxine (32.80 vs. 6.55 µIU/ mL, p 0.0001). Other factors associated with TCH were results of thyroid ultrasonography (p 0.007), gestational age at birth (p 0.02), and maternal history of thyroid illness (p < 0.0001).

Of all the patients with confirmed congenital hypothyroidism via the newborn screening, 6.97% were diagnosed with transient CH. Factors associated with TCH are confirmatory TSH and FT4, L-thyroxine dose requirements, thyroid ultrasound findings, gestational age at birth, and a maternal history of thyroid illness.

BACKGROUND AND OBJECTIVE

Transient congenital hypothyroidism (TCH) refers to temporary deficiency of thyroid hormone identified after birth which later recovers to improved thyroxine production. Its prevalence in the Philippines has not been reported in a large-scale study. Its diagnosis remains difficult due to its numerous possible etiologies. Identifying the predictive factors of TCH may aid in earlier diagnosis and decreased risk of overtreatment. This study aimed to determine the predictive factors for TCH in children with congenital hypothyroidism (CH) detected by newborn screening (NBS) in the Philippines from January 2010 to December 2017.

In this multicenter retrospective cohort study involving 15 NBS continuity clinics in the Philippines, medical records were reviewed, and clinical and laboratory factors were compared between children with TCH and those with permanent congenital hypothyroidism (PCH). Of the 2,913 children diagnosed with CH in the Philippines from 2010 to 2017, 1,163 (39.92%) were excluded from the study due to an unrecalled or lost to follow-up status, or a concomitant diagnosis of Down Syndrome.

Among the 1,750 patients included in analysis, 6.97% were diagnosed with TCH, 60.80% were female, mean gestational age at birth was 38 weeks, and mean birth weight was 2,841 grams. Confirmatory thyrotropin (TSH) was lower and confirmatory free thyroxine (FT4) was higher in the TCH group compared to those with PCH (TSH 32.80 vs 86.65 µIU/mL [pCONCLUSION

Of all the patients with confirmed congenital hypothyroidism via the newborn screening, 6.97% were diagnosed with transient CH. Factors associated with TCH are confirmatory TSH and FT4, L-thyroxine dose requirements, thyroid ultrasound findings, gestational age at birth, and a maternal history of thyroid illness.

BACKGROUND: Subclinical hypothyroidism (SCH) has been reported to be associated with lower endothelial progenitor (CD34-positive) cell count, whereas an inverse association between circulating CD34-positive cell count and height loss is documented. Reports indicate height loss to be associated with all-cause mortality, and a higher CD34-positive cell count has been shown to predict longer life. Therefore, evaluating the association between SCH and height loss provides mechanistic insights underlying the association between height loss and mortality risk. METHODS: A prospective study involving 1,599 participants with normal free triiodothyronine (T3) and free thyroxine (T4) levels was conducted to determine the association between SCH and height loss.Since the free T4 level influences the supply of active thyroid hormone (free T3), the analysis was stratified by the median free T4 level. Height loss was defined as the highest quintile of annual height decrease. RESULTS: SCH was positively associated with height loss in participants with low-normal free T4 levels (below the median), but not in those with high-normal free T4 levels (at or above the median). After adjusting for sex, age, free T3 level, atherosclerosis, and known cardiovascular risk factors, the adjusted odds ratios (95% confidence interval) for height loss were 1.88 (1.02, 3.47) and 1.92 (1.02, 3.62) in the low-normal free T4 group. The corresponding values in the high-normal free T4 group were 0.37 (0.08, 1.69) and 0.43 (0.09, 1.97). CONCLUSION SCH could influence height loss, and free T4 might influence the association between SCH and height loss in euthyroid individuals. These results clarify the mechanisms underlying the association between height loss and mortality risk.
Humans ; Hypothyroidism/epidemiology* ; Thyroxine/blood* ; Male ; Female ; Prospective Studies ; Middle Aged ; Body Height ; Adult ; Aged ; Risk Factors

Objective: This study aims to determine the effect of iodine excess in pregnant mothers on thyroid function, growth and neurodevelopment in the neonates when assessed at 12 weeks of age. Methodology: This prospective study enrolled term neonates with birth weight >2500 gm of mothers having urine iodine concentration (UIC) ≥500 µg/L documented in the third trimester of the peripartum period. Neonatal TSH was collected by heel prick on dried blood spots within 24-72 hours of age and measured by time-resolved fluroimmunoassay. Neonates with TSH ≥11 mIU/L at birth were followed up at 2 and 12 weeks to monitor thyroid dysfunction, growth and development. Results: A total of 2354 (n = 1575 in the delivery room) maternal urine samples were collected of which 598 (25.4%) had elevated UIC. Forty-nine (12.2%) neonates had TSH ≥11mIU/L on newborn screening of whom 18 and 3 neonates had residual elevated TSH at 2 and 12 weeks of life, respectively. Maternal iodine levels correlated weakly with TSH at 2 weeks (rho = 0.299; p = 0.037). No child required treatment for congenital hypothyroidism. Eight babies additionally had TSH >5 mIU/L at 12 weeks of life. The growth and development of babies with or without TSH elevation was comparable at three months (p > 0.05). Conclusion Maternal iodine excess in pregnancy and peripartum period causes transient hyperthyrotropinemia in neonates that did not affect the growth and development at 3 months of age.
Thyroid ; Thyroid Gland ; Hypothyroidism ; Thyroid Function Tests

OBJECTIVES

This study aimed to determine the clinical profile of non thyroidal cancer patients with thyroid dysfunction associated with tyrosine kinase inhibitor (TKI) therapy at the University of Santo Tomas Hospital (USTH), Philippines.

This is a retrospective observational study of TKI initiated adult non-thyroidal cancer patients with thyroid function testing from 2013 to 2018.

Forty percent (95% CI: 26.2% - 58.61%) of the sixty individuals who had thyroid function tests (TFT) had incident thyroid dysfunction. Thirty percent had hypothyroidism (i.e., 25% overt [mean TSH 16.64 uIU/mL]; 5% subclinical [mean TSH 6.62 uIU/mL]). The median time at risk was 8 and 16 months for overt and subclinical hypothyroidism, respectively. Fifty-six percent had persistent hypothyroidism (median TSH 16.75, p = 0.009). The average time to recovery of transient hypothyroidism was 39 months. Ten percent had hyperthyroidism with a median time at risk of 1.5 months. Non-small cell lung cancer and renal cell carcinoma were possible associated risk factors of thyroid dysfunction.

TKI-induced thyroid dysfunctions are common. Screening and monitoring for thyroid abnormalities during TKI therapy is important.