Background/Objectives: Pediatric osteoporosis is a multifactorial condition characterized by impaired bone mineralization and increased fracture risk, particularly vertebral compression fractures. This study aims to evaluate the diverse etiology, diagnostic challenges, and treatment options for pediatric osteoporosis in a cohort of affected children. Methods: We reviewed eleven pediatric patients (aged 5–16 years) diagnosed with vertebral fractures and osteoporosis, who were hospitalized between 2020 and 2024 at the Department of Endocrinology and Metabolic Diseases at PMMH-RI in Lodz. Clinical evaluation included medical history, physical examination, biochemical markers of bone metabolism, and imaging techniques such as dual-energy X-ray absorptiometry (DXA) to determine underlying causes of bone fragility. Results: The cohort presented a broad etiological spectrum, including seven patients with genetic disorders (e.g., mutations in COL1A1, LRP5, SGMS2, and ALPL genes) and secondary osteoporosis due to chronic diseases requiring prolonged glucocorticoid therapy (two patients with Duchenne muscular dystrophy (DMD), one patient with Crohn’s disease) or endocrinological disorders (one patient with Cushing disease). Vertebral fractures were confirmed in all patients, with back pain as the predominant symptom. Low bone mass (BMD Z-score < −2.0) was observed in eight individuals; in others, clinical signs of skeletal fragility were present despite Z-scores above this threshold. Mild biochemical abnormalities included hypercalciuria (3/11 cases) and vitamin D deficiency (6/11 cases). Height adjustment improved BMD interpretation in short-stature patients. Most children received bisphosphonate therapy, supplemented with calcium and vitamin D. In two patients, bisphosphonates were not used due to lack of parental consent or underlying conditions in which such treatment is not recommended. Conclusions: Pediatric osteoporosis requires a multidisciplinary diagnostic and therapeutic approach, integrating clinical, biochemical, and genetic factors. It is a heterogeneous and often underrecognized condition, with vertebral fractures frequently serving as its earliest sign—even in the absence of overt symptoms or low bone mass. This underscores the need for clinical vigilance, as significant skeletal fragility may occur despite normal BMD values. Importantly, pediatric osteoporosis may also impact the attainment of peak bone mass and ultimately affect final adult height. Early diagnosis through thorough assessment, including height-adjusted DXA, and a multidisciplinary approach are essential to ensure timely management and prevent long-term complications.

Background: Recognizing insulin resistance (IR) in children remains challenging due to uncertain IRI-HOMA cut-offs and unclear recommendations for evaluating IR based on OGTT. In our study, we compare the effectiveness of IRI-HOMA and IRI-Belfiore (OGTT-based) in detecting IR and its metabolic complications in children. Methods: The analysis included 553 children who were hospitalized at the Department of Endocrinology and Metabolic Diseases of the Polish Mother’s Memorial Hospital Research Institute (PMMH-RI) in Lodz, Poland, between 2002 and 2018 due to various reasons—of these, 67.5% were girls. All underwent OGTT for glucose and insulin assessment. IR diagnosis relied on IRI-HOMA and IRI-Belfiore. IR based on IRI-HOMA was evaluated using three criteria: (A) >2.5; (B) >2.67 in boys and >2.22 in girls before puberty and >5.22 and >3.82 during puberty, respectively; (C) >95th percentile according to charts for IRI-HOMA in children. Results: Prepubertal children exhibited significantly lower IRI-HOMA and IRI-Belfiore than their pubertal counterparts (p < 0.00005). IRI-HOMA and IRI-Belfiore values positively correlated with age and BMI SDS value (p < 0.000001 for all calculations). As many as 26% to 46.9% of children with normal IRI-HOMA showed elevated IRI-Belfiore, with notably higher levels of triglycerides, a lower HDL cholesterol fraction, and a lower HDL/total cholesterol ratio in this subgroup. Conclusions: A notable proportion of children exhibited elevated IRI-Belfiore levels despite having normal IRI-HOMA values. This suggests the possibility of peripheral IR preceding hepatic IR in children—omitting an OGTT may therefore lead to overlooking cases of IR. Children diagnosed with IR via OGTT displayed significantly poorer lipid profiles compared to those without IR (characterized by normal values in both IRI-HOMA and IRI-Belfiore). This underscores the ability of OGTT-derived IR indices to identify individuals at risk of developing complications associated with obesity and IR before the onset of metabolic syndrome (MS) symptoms. If IR is already detected in children based on fasting glucose and insulin levels (IRI-HOMA), further evaluation may not be warranted, as OGTT results often simply confirm the diagnosis.

Hypophosphatemic rickets is a rare disease that results in bone deformities. However, little is known about bone turnover and bone mass disorders in this disease. This retrospective study included 12 children aged 1–16 years diagnosed with hypophosphatemic rickets. Parameters of calcium-phosphate metabolism and bone turnover markers were analysed. Bone mineral density was assessed with the use of dual-energy X-ray absorptiometry, and indices of quantitative ultrasound examination of tibiae and radial bones were analysed. In the majority of patients, hypophosphatemia and hyperphosphaturia were present. The assessed bone turnover markers showed increased bone formation. Increased pyridinoline levels were found in 5 out of 12 patients. Bone mineral density was decreased only in one patient. Decreased values of quantitative ultrasound examination were observed in all the analysed patients. Conclusions: (1) Bone metabolism disturbances, reflected in the increased values of bone turnover markers and worse bone quality, were found in the group of patients with hypophosphatemic rickets. (2) It is crucial to determine bone turnover markers, dual-energy X-ray absorptiometry findings and indices of quantitative ultrasound examination in order to monitor progress of the disease, as well as treatment effects.

The aim of the study was to investigate the effects of seasonal variability of insolation, the implementation of new recommendations for vitamin D supplementation (2018), and the SARS-CoV-2 pandemic lockdown (2020) on 25(OH)D concentrations in children from central Poland. The retrospective analysis of variability of 25(OH)D concentrations during the last 8 years was performed in a group of 1440 children with short stature, aged 3.0–18.0 years. Significant differences in 25(OH)D concentrations were found between the periods from mid-2014 to mid-2018, from mid-2018 to mid-2020, and from mid-2020 to mid-2022 (medians: 22.9, 26.0, and 29.9 ng/mL, respectively). Time series models created on the grounds of data from 6 years of the pre-pandemic period and used for prediction for the pandemic period explained over 80% of the seasonal variability of 25(OH)D concentrations, with overprediction for the first year of the pandemic and underprediction for the second year. A significant increase in 25(OH)D concentrations was observed both after the introduction of new vitamin D supplementation guidelines and during the SARS-CoV-2 pandemic; however, the scale of vitamin D deficiency and insufficiency was still too high. Time series models are useful in analyzing the impact of health policy interventions and pandemic restrictions on the seasonal variability of vitamin D concentrations.

Background: Inflammatory bowel diseases (IBD), such as Crohn’s disease (CD) and ulcerative colitis (UC), may impair bone metabolism, particularly in children. The RANKL/OPG axis, as a key regulator of bone turnover, may contribute to these disturbances. However, data in the pediatric population remain limited. Methods: A single-center, prospective observational study included 100 children aged 4–18 years, with a comparable number of girls and boys. Among them, 72 had IBD (27 CD, 45 UC) and 28 were healthy controls. Anthropometric, biochemical, and densitometric assessments were performed, including serum levels of RANKL and OPG, and markers of inflammation and bone turnover. Results: Children with CD had significantly lower height and weight percentiles compared to UC and controls. Serum RANKL and the RANKL/OPG ratio were significantly elevated in IBD patients, particularly in CD (p < 0.01). Total body BMD Z-scores were lower in IBD compared to controls (p = 0.03). Low BMD was found in 14.7% of UC and 26.3% of CD patients. In both groups, over 30% had values in the “gray zone” (−1.0 to −2.0). A positive correlation was observed between height and weight and bone density (p < 0.01). Higher OPG was associated with lower body weight (p < 0.001), while increased RANKL correlated with osteocalcin (p = 0.03). Patients receiving biological therapy had significantly lower BMD. Conclusions: Pediatric IBD is associated with significant alterations in the RANKL/OPG axis and reduced bone density. These findings support early screening and suggest RANKL/OPG as a potential biomarker of skeletal health.

Background/Objectives: The skeletal system reaches peak bone mass through modeling and remodeling processes, influenced by environmental, dietary, hormonal, and genetic factors. In children with endocrinopathies, disturbances in bone mass and mineralization may correlate with hormonal levels, but conditions like short stature or obesity can confound DXA results. This study aimed to assess the prevalence of decreased bone mineral density (BMD) in children with endocrine disorders and evaluate the impact of auxological and hormonal abnormalities on BMD. Methods: This study analyzed medical records of 148 children (mean age 11.85 ± 3.34 years); 73 girls and 75 boys). Conditions included obesity (22.9%), short stature (47.9%), precocious puberty (10.1%), and other diagnoses. Clinical data included primary diagnosis, height, body weight, pubertal stage, and serum concentrations of calcium, phosphate, alkaline phosphatase, 25OHD, PTH, osteocalcin, Crosslaps, TSH, fT4, IGF-1, IGF-BP3, cortisol, estradiol, testosterone, and bone age. DXA scans were performed at the total body less head (TBLH) and lumbar spine (Spine) projection. Results: Low bone mass (aBMD Z-score ≤ −2) was found in 34.46% at TBLH and 15.54% at the Spine. After height adjustment (HAZ adjustment), the prevalence of low bone mass decreased to 11.4% at TBLH and 4.1% at the Spine. In the short stature group, the normalization of Z-scores for height significantly reduced abnormal results. A positive correlation was found between DXA parameters and age, height standard deviation score (HSDS), BMI SDS, estradiol, testosterone, IGF-1, and IGF-BP3. A negative correlation existed between vitamin D and DXA parameters. Bone turnover markers (osteocalcin and Crosslaps) also negatively affected bone mass. No significant correlations were found with PTH, TSH, fT4, or cortisol. In children with growth retardation, lower aBMD_HAZ Z-scores were observed in those with decreased IGF-1. Positive correlations existed between BMI SDS, IGF-1, and adjusted aBMD Z-scores. Conclusions: Children with endocrine disorders, especially those with short stature, are at risk for bone mineralization disorders. Height normalization is crucial for accurate DXA interpretation and avoiding overdiagnosis. Positive influences on bone mass include height, BMI, IGF-1, estradiol, and testosterone, while negative factors include bone turnover markers and low vitamin D.