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.

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.

Hypophosphatasia (HPP) is a rare, and usually diagnosed with delay, genetic disease caused by a mutation in the alkaline phosphatase liver/bone/kidney type (ALPL) gene. Low activity of the alkaline phosphatase (ALP) impairs the hydroxyapatite formation, reducing skeletal mineralization. The aim of the study was to present patients diagnosed with HPP. The data from the history and medical records of patients were analyzed. In the study group, one patient was diagnosed with perinatal type of HPP, three were diagnosed with infant variant, eight were diagnosed with children variant, two were diagnosed with odontohypophosphatasia, and two were diagnosed with the adult type of the disease. The most frequently presented symptoms included premature loss of teeth in 11/16 (68.75%) patients, bone deformities in 10/16 (62.5%) patients, chronic bone pain in 9/16 (56.25%) patients, and fractures in 8/16 (50%) patients. Reduction in bone mineral density in at least one examined projection has been found in 11/14 patients. Conclusions: The correct diagnosis of HPP is difficult due to the variety of types and clinical symptoms, as well as the very rare occurrence of this disease. Both lower and upper reference values of the determined biochemical parameters may be important in HPP diagnostics.