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.

Management of patients with X-linked hypophosphatemic rickets during Covid-19 pandemic lockdown.

OBJECTIVES: To identify a safe pathway for management and treatment of patients with X-linked hypophosphatemic rickets (XLH) during Covid-19 pandemic lockdown. METHODS: Twenty-six patients with XLH (age 3.1-25.7 years) were enrolled in Pediatric Endocrine Unit; nine of them were receiving human monoclonal anti-fibroblast growth factor 23 antibody (burosumab) and 17 (pediatric patients, age 9.5-17.9 years, n=7; young-adult patients, age 20.1-25.7 years, n=10) received conventional treatment with inorganic oral phosphate salts and active vitamin D metabolites. A Covid-19 free pathway was addressed for XLH patients receiving burosumab treatment in hospital. XLH patients receiving conventional treatment were followed by phone calls, e-mails, or telemedicine. RESULTS: All XLH patients receiving burosumab continued the scheduled follow-up and treatment; none of them was infected by Covid-19. Seven XLH patients out of 17 (41%) receiving conventional treatment showed some complication related to the disease itself or its treatment: periapical abscess with gingival fistula was diagnosed in five patients (three children and two young-adults) and treated with antibiotics with complete resolution; one child showed abdominal pain due to the administration of high doses of inorganic oral phosphate salts solved by reducing the dosage, and one child had severe legs pain during deambulation after orthopedic surgery solved with common analgesics. CONCLUSIONS: Covid-19 free pathway was safe and effective to manage XLH patients receiving burosumab. E-health technologies were useful methods to follow XLH patients receiving conventional treatment during Covid-19 pandemic lockdown.

Adolescent Gynecomastia due to Minimal Androgen Resistance Syndrome: A Case Report and Literature Review.

A 14-year-old boy with a 46,XY karyotype and persistent breast-3-stage gynecomastia is reported. The reproductive axis was investigated by standard laboratory methods and the androgen receptor (AR) gene was sequenced. Also, a literature review of phenotypes associated with the AR genetic variant p.Pro392Ser was performed. The boy presented with height in the upper normal range (+1.9 SDS) and normal body mass index (-0,3 SDS); pubertal development was PH5/G4 (mean testicular volume 15 mL; 0 SDS). Laboratory findings were normal for age and sex, except aromatization index (0.09; reference range 0.03-0.07). Analysis of the AR gene showed the single nucleotide variant c.1174C>T (p.Pro392Ser) in exon 1, leading to the diagnosis of minimal androgen insensitivity syndrome (AIS). This genetic variant is reported in other 8 patients with AIS and is associated with variable clinical phenotypes ranging from complete to partial and minimal AIS. To the best of our knowledge, this is the first adolescent in whom the p.Pro392Ser mutation is associated with isolated persistent gynecomastia. The underlying reason of phenotypic variability due to this AR mutation remains unknown. Persistent gynecomastia due to minimal AIS has been reported in few additional males with variable AR mutations. Since fertility troubles may occur in adult men with minimal AIS, early diagnosis can allow optimizing the clinical management.

Hard ways towards adulthood: the transition phase in young people with myotonic dystrophy.

Myotonic dystrophy type 1 (DM1), also called Steinert's disease, is a genetic multisystem disorder that has raised, in the last years, high interest because of the high variable clinical spectrum and related disability. Children with myotonic dystrophy are affected by behavioural problems and intellectual disability, finally impacting on their degree of engagement in family, work and social activities. The transition phase, representing the process of moving from adolescence to adulthood, can be severely affected by growing up with a neuromuscular disorder, with significant impact on patient's and families' quality of life. Although conceptual models of health assistance for individual with genetic disorders have already been proposed the burden for the patient and his family is still relevant. Therefore to afford this critical condition it would be suitable to plan proper educational and psychosocial programs, identifying areas of unmet needs and targeted health objectives that ensure the right support to DM1 population.