Background: Longitudinal bone growth is regulated by multiple endocrine signals (e.g. growth hormone, insulin-like growth factor I, estrogen, androgen) and local factors (e.g. fibroblast growth factors and their receptors and the C-natriuretic peptide/NPR-2 pathway). Summary: Abnormalities in both endocrine and local regulation of growth plate physiology cause many disorders of human skeletal growth. Knowledge of these pathways creates therapeutic potential for sustaining or even augmenting linear growth. Key message: During the past four decades, advances in understanding growth plate physiology have been accompanied by development and implementation of growth-promoting treatments that have progressed in both efficacy and specificity of action. This paper reviews the history and continuing evolution of growth plate therapeutics.

We report three patients with elevations of propionylcarnitine (C3), one without elevations of 2-methylcitrate and 3-hydroxypropionate in urine organic acid analysis, and the other two showing only mild elevations, all of whom were subsequently confirmed to have propionic acidemia by molecular analysis of PCCA and PCCB genes. To date, they have had a mild clinical course. These cases illustrate the importance of considering high C3 as the only biochemical abnormality in a diagnosis of propionic acidemia. Since mild C3 elevations may be overlooked and considered non-diagnostic in isolation, we advise considering a diagnosis of propionic acidemia even in the absence of significant elevations 2-methylcitrate or 3-hydroxypropionate in urine organic acid analysis.Abbreviations 2-MCA 2-Methylcitrate 3-OHP 3-Hydroxypropionate C3 Propionylcarnitine

Objective: Severe 25-hydroxyvitamin D (25(OH)D) deficiency can result in life-threatening presentations due to hypocalcemia leading to seizures and cardiac arrhythmias. Vitamin D deficiency is a common cause of hypocalcemia and rickets in children; however, there are no recent studies on the burden of inpatient admissions in the United States. Our study aims to describe the clinical characteristics and risk factors of inpatient admissions due to severe hypocalcemia and 25(OH)D deficiency at a freestanding academic children’s hospital. Methods: A descriptive retrospective chart review was completed on all inpatient admissions from 2016 to 2021 for children 0–18 years of age with corrected calcium <8 mg/dL and 25(OH)D <10 ng/mL during admission. Results: Thirty-eight patients met the inclusion criteria (74 % Black/African American). Neurological signs described in 49 %, bone abnormalities in 17 % and EKG abnormalities in 42 % of the patients. The mean calcium serum level was 6.0 mmol/L (range 5.0–7.9 mmol/L), the mean iCa 0.77 mmol/L (range 0.54–0.99 mmol/L). The mean level of 25(OH)D was 5.5 ng/mL (range 2.1–9.7 ng/mL). The median length of stay was 4.5 (range 1–59 days). Conclusion: In this retrospective observational study, risk factors identified: (1) Black/African American race (2) age less than two years (3) lack of supplementation of vitamin D and (4) dietary restrictions. Inpatient admissions are preventable through the implementation of education at the community and healthcare levels.

Background. McCune-Albright syndrome (MAS) is characterized by hyperpigmented macules, endocrinopathies, and fibrous dysplasia. Hyperthyroidism is the second most common endocrinopathy in MAS and its management is challenging, particularly among infants and toddlers. Traditionally, young infants have been treated with antithyroid medications, but remission is likely and these medications have severe side effects and affect the control of other endocrinopathies. Thus, it is reasonable to consider permanent treatment options at an earlier age. In this article, we performed a retrospective chart review and describe 3 children who underwent thyroidectomy at an early age due to complex presentation. Case Descriptions. Case 1 was a female patient who underwent bilateral adrenalectomy due to adrenal hyperplasia and subsequently underwent thyroidectomy at 5 months of age due to unremitting hyperthyroidism with fibrous dysplasia, multiple fractures, and ovarian cysts with vaginal bleeding. Case 2 was a 20-month-old female on methimazole who acquired influenza A, precipitating a thyroid storm, and subsequently developed central precocious puberty. Case 3 was a 4-year-old female who underwent thyroidectomy because of unremitting hyperthyroidism after methimazole cessation due to declining neutrophils. All 3 children experienced no complications from thyroidectomy. Conclusions. Early thyroidectomy by an experienced surgeon is an option for managing MAS-associated hyperthyroidism, even in very young patients, with excellent results.