Diagnosis, treatment, and management of rickets: a position statement from the Bone and Mineral Metabolism Group of the Italian Society of Pediatric Endocrinology and Diabetology.

Rickets results from impaired mineralization of growing bone due to alterations in calcium and phosphate homeostasis. Clinical signs of rickets are related to the age of the patient, the duration of the disease, and the underlying disorder. The most common signs of rickets are swelling of the wrists, knees or ankles, bowing of the legs (knock-knees, outward bowing, or both) and inability to walk. However, clinical features alone cannot differentiate between the various forms of rickets. Rickets includes a heterogeneous group of acquired and inherited diseases. Nutritional rickets is due to a deficiency of vitamin D, dietary calcium or phosphate. Mutations in genes responsible for vitamin D metabolism or function, the production or breakdown of fibroblast growth factor 23, renal phosphate regulation, or bone mineralization can lead to the hereditary form of rickets. This position paper reviews the relevant literature and presents the expertise of the Bone and Mineral Metabolism Group of the Italian Society of Pediatric Endocrinology and Diabetology (SIEDP). The aim of this document is to provide practical guidance to specialists and healthcare professionals on the main criteria for diagnosis, treatment, and management of patients with rickets. The various forms of rickets are discussed, and detailed references for the discussion of each form are provided. Algorithms to guide the diagnostic approach and recommendations to manage patients with rare forms of hereditary rickets are proposed.

Different Efficacy of Burosumab on Physical Performance and Serum Phosphate in Adult Patients with X-Linked Hyphophosphatemic Rickets during the First Six-Month of Treatment.

Burosumab is a monoclonal anti-FGF23 antibody used to treat patients with X-linked hypophosphatemic rickets (XLH). Its effect on serum phosphate and physical performance was compared in patients during a 6-month treatment with burosumab. Eight adult patients with XHL were treated with burosumab (1 mg/kg s.c. every 28 days). In the first 6 months of treatment, calcium-phosphate metabolism variables were measured, and muscle performance (tested with chair and walking test) and quality of life (tested with fatigue, BPI-pain and BPI-life questionnaires) were estimated. A significant increase in serum phosphate was observed during the treatment. From the 16th week, serum phosphate became significantly lower than its value in the 4th week. No patients had serum phosphate below the normal range at the 10th week, but seven patients were hypophosphatemic in the 20th and 24th week. All patients improved the execution time of the chair test and walking test, which reached a plateau after the 12th week. BPI-pain and BPI-life scores significantly decreased from baseline to the 24th week. In conclusion, a six-month burosumab treatment may significantly improve the general condition and physical performance of adult patients with XLH; this improvement was more stable and more indicative of treatment efficacy than that of serum phosphate.

Real-life long-term efficacy and safety of recombinant human growth hormone therapy in children with short stature homeobox-containing deficiency.

Objective: This Italian survey aims to evaluate real-life long-term efficacy and safety of recombinant human growth hormone (rhGH) therapy in children with short stature homeobox-containing gene deficiency disorders (SHOX-D) and to identify potential predictive factors influencing response to rhGH therapy. Design and methods: This is a national retrospective observational study collecting anamnestic, anthropometric, clinical, instrumental and therapeutic data in children and adolescents with a genetic confirmation of SHOX-D treated on rhGH. Data were collected at the beginning of rhGH therapy (T0), yearly during the first 4 years of rhGH therapy (T1, T2, T3 and T4) and at near-final height (nFH) (T5), when available. Results: One hundred and seventeen SHOX-D children started rhGH therapy (initial dose 0.23 ± 0.04 mg/kg/week) at a mean age of 8.67 ± 3.33 years (74% prepubertal), 99 completed the first year of treatment and 46 reached nFH. During rhGH therapy, growth velocity (GV), standard deviation score (SDS) and height (H) SDS improved significantly. Mean H SDS gain from T0 was +1.14 ± 0.58 at T4 and +0.80 ± 0.98 at T5. Both patients carrying mutations involving intragenic SHOX region (group A) and ones with regulatory region defects (group B) experienced a similar beneficial therapeutic effect. The multiple regression analysis identified the age at the start of rhGH treatment (ß = -0.31, P = 0.030) and the GV during the first year of rhGH treatment (ß = 0.45, P = 0.008) as main independent predictor factors of height gain. During rhGH therapy, no adverse event of concern was reported. Conclusions: Our data confirm the efficacy and safety of rhGH therapy in SHOX-D children, regardless the wide variety of genotype. Significance Statement: Among children with idiopathic short stature, the prevalence of SHOX-D is near to 1/1000-2000 (1.1-15%) with a wide phenotypic spectrum. Current guidelines support rhGH therapy in SHOX-D children, but long-term data are still few. Our real-life data confirm the efficacy and safety of rhGH therapy in SHOX-D children, regardless of the wide variety of genotypes. Moreover, rhGH therapy seems to blunt the SHOX-D phenotype. The response to rhGH in the first year of treatment and the age when rhGH was started significantly impact the height gain.

Safety and Efficacy of Pamidronate in Neonatal Hypercalcemia Caused by Subcutaneous Fat Necrosis: A Case Report.

Subcutaneous fat necrosis of the newborn (SCFN) is a panniculitis that develops in fatty areas after fetal or perinatal distress. Prognosis is generally good with complete regression, but it can be complicated by metabolic abnormalities like hypoglycemia, hypertriglyceridemia, thrombocytopenia, and also potentially life-threatening hypercalcemia. Treatments have included hydration, furosemide and corticosteroids. These treatments can be prolonged for several days and can have complications such as nephrocalcinosis. Use of bisphosphonates has been rarely reported in newborn. We describe a case of severe hypercalcemia complicating subcutaneous fat necrosis in a newborn successfully treated by a single dose of pamidronate after having obtained partial response by therapy with hyperhydration, furosemide and hydrocortisone. When high levels of calcium do not respond to first line therapy with hyperhydration and diuretic therapy, bisphosphonates treatment could be considered a valid choice to treat hypercalcemia and to avoid corticosteroids. Further studies are needed to understand if pamidronate and other bisphosphonates can be considered the first choice in hypercalcemia due to SCFN.

Pseudohypoparathyroidism: application of the Italian common healthcare-pathway for a homogeneous clinical approach and a shared follow up.

BACKGROUND: Pseudohypoparathyroidism (PHP) represents a heterogeneous group of rare endocrine disorders caused by (epi) genetic abnormalities affecting the GNAS locus. It is mainly characterized by resistance to PTH and TSH, and by peculiar clinical features such as short stature, obesity, cognitive impairment, subcutaneous ossifications and brachydactyly. Delayed puberty, GHRH and calcitonin resistances have also been described. The healthcare-pathway recently proposed by the Italian Society of Pediatric Endocrinology and Diabetology (ISPED) has provided a standardized clinical approach to these conditions. The purpose of the present study was to evaluate its application in clinical practice, and to collect data for setting future specific studies. METHODS: Through a semi-structured survey, based on the indications of the care-pathway, data on PHP clinical management were collected. The compilation of each data in the survey was read as an index of the adoption of the healthcare-pathway in clinical practice. RESULTS: In addition to the proposing Center, 4 Centers joined the study, thus obtaining a large collection of data on 48 PHP patients. Highest rates in the completion of data were obtained for diagnostic history, auxological measurements and subcutaneous ossifications evaluation. As expected, the availability of data for the other investigated fields was lower, coming from recent research studies. More information has been obtained on hormonal resistance classically involved in PHP (PTH, TSH, GHRH and GnRH) and on cognitive impairment, while a few data has been collected on bone mineral status, calcitonin levels and glucolipid metabolism. CONCLUSIONS: The presented data show that the ISPED healthcare-pathway could represent a valid tool both to confirm the clinical approach to PHP patients and to allow homogeneous data collection; however, it has not yet been fully adopted. The strengthening of the network among the major Italian Endocrine Centers will contribute to improve its application in clinical practice, optimizing the follow-up of these patients and increasing knowledge on PHP.

COVID-19 infection in a paucisymptomatic infant: Raising the index of suspicion in epidemic settings.

Few children have been reported to have been affected by novel coronavirus disease 2019 (COVID-19); it is unclear whether children are less likely to be infected or rather display fewer symptoms. We present the case of a 32-day-old boy infected by COVID-19 that presented with an upper air way infection which resolved spontaneously and did not require any therapy. We argue that in epidemic settings children presenting with any mild symptom potentially attributable to COVID-19 should be considered contagious until proven otherwise, and that management must be guided by clinical conditions.