Safety and efficacy of burosumab in improving phosphate metabolism, bone health, and quality of life in adolescents with X-linked hypophosphatemic rickets.

BACKGROUND AND OBJECTIVE: X-linked hypophosphatemic rickets (XLH) is due to loss-of-function mutations in the phosphate-regulating endopeptidase homologue on the X chromosome (PHEX) that lead to increased fibroblast growth factor 23 (FGF23) production. FGF23 excess causes renal phosphate wasting and insufficient 1,25-dihydroxyvitamin D (1,25(OH)2D) synthesis with reduced intestinal phosphate absorption, ultimately resulting in chronic hypophosphatemia. Children with XLH show typical skeletal lesions of rickets, deformities of the lower limbs, stunted growth with disproportionate short stature, bone pain, and physical dysfunctions. Burosumab, a fully human IgG1 monoclonal antibody that binds to FGF23 to inhibit its activity, is more effective to improve the biochemical and clinical signs of XLH than conventional treatment with phosphate supplements and vitamin D active metabolites. Data on adolescents with XLH during the transition period to young adulthood are few. In this prospective case series, we aimed to assess safety and efficacy of burosumab in adolescents with XLH who discontinued long-term conventional therapy. METHODS: Five Caucasian adolescents (4 males, 1 female; mean age 15.4 ± 1.5 years) with XLH were recruited and switched from conventional treatment to burosumab (0.8-1.2 mg/kg, s. c. QW2). Burosumab was continued for 12-48 months and, once discontinued, patients were followed-up for 6-12 months. In all patients, serum calcium, phosphate, alkaline phosphatase (ALP), parathyroid hormone (PTH), and 1,25(OH)2D levels, and renal tubular reabsorption of phosphate (TmP/GFR) values were assessed at entry and during burosumab. Intact FGF23 plasma levels were measured at entry. Patient-reported outcomes (PROs) were assessed at entry and every 3-6 months to evaluate the impact of low extremity pain, stiffness, and difficulties performing daily activities. RESULTS: At entry, all patients showed hypophosphatemia, increased intact FGF23 levels, reduced TmP/GFR, insufficient 1,25(OH)2D levels, and in four out of five increased ALP levels. Two patients had radiological signs of rickets. During burosumab, all patients showed a significant increase in serum phosphate and 1,25(OH)2D levels, and in TmP/GFR values (P < 0.05 - P < 0.0001). Serum ALP levels significantly declined (P < 0.05) to normal values. No changes of serum calcium and PTH levels (PNS) were found during burosumab. PROs significantly improved (P < 0.02 - P < 0.0001) in all patients. Four patients discontinued burosumab when they turned 18 or 19, whereas one continued the treatment since he was still younger than 18 during the study period. Four patients who suspended burosumab showed a rapid decline in serum phosphate and 1,25(OH)2D levels and in TmP/GFR values; serum ALP levels increased, and PROs progressively worsened with a significant reduction in quality of life. These consequences were not observed in the patient who continued burosumab treatment. DISCUSSION: Our data showed that conventional treatment improved only in part the signs and symptoms of XLH. Burosumab was well tolerated and was effective in improving phosphate metabolism, bone health, and PROs. All the benefits of burosumab were lost after its discontinuation. These results suggested that continuing burosumab is required to achieve and maintain the clinical benefits of the treatment during the transition to young adulthood in patients with XLH.

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.

Serum 25-hydroxyvitamin D threshold and risk of rickets in young children: a systematic review and individual participant data meta-analysis to inform the development of dietary requirements for vitamin D.

PURPOSE: The objective of this systematic review was to determine a minimum serum 25-hydroxyvitamin D (25OHD) threshold based on the risk of having rickets in young children. This work was commissioned by the WHO and FAO within the framework of the update of the vitamin D requirements for children 0-3 years old. METHODS: A systematic search of Embase was conducted to identify studies involving children below  4 years of age with serum 25OHD levels and radiologically confirmed rickets, without any restriction related to the geographical location or language. Study-level and individual participant data (IPD)-level random effects multi-level meta-analyses were conducted. The odds, sensitivity and specificity for rickets at different serum 25OHD thresholds were calculated for all children as well as for children with adequate calcium intakes only. RESULTS: A total of 120 studies with 5412 participants were included. At the study-level, children with rickets had a mean serum 25OHD of 23 nmol/L (95% CI 19-27). At the IPD level, children with rickets had a median and mean serum 25OHD of 23 and 29 nmol/L, respectively. More than half (55%) of the children with rickets had serum 25OHD below 25 nmol/L, 62% below 30 nmol/L, and 79% below 40 nmol/L. Analysis of odds, sensitivities and specificities for nutritional rickets at different serum 25OHD thresholds suggested a minimal risk threshold of around 28 nmol/L for children with adequate calcium intakes and 40 nmol/L for children with low calcium intakes. CONCLUSION: This systematic review and IPD meta-analysis suggests that from a public health perspective and to inform the development of dietary requirements for vitamin D, a minimum serum 25OHD threshold of around 28 nmol/L and above would represent a low risk of nutritional rickets for the majority of children with an adequate calcium intake.

Clinical, Immunological, and Genetic Findings in a Cohort of Patients with the DiGeorge Phenotype without 22q11.2 Deletion.

Chromosome 22q11.2 deletion syndrome (22q11.2DS) is a primary immunodeficiency characterized by a broad and heterogeneous clinical presentation associated with various degrees of T-cell deficiency. We report the clinical, immunologic, and genetic findings of a cohort of eight patients presenting with a clinical phenotype that is highly suggestive of this syndrome but without the 22q11.2 deletion. The cardinal features of 22q11.2DS, such as congenital heart defects, hypoparathyroidism, and facial dysmorphisms, were observed in the majority of the patient cohort. The unusual features are described in detail. The immunologic assessment showed various degrees of immunodeficiency of the T-cell compartment, notably a reduction in the thymic output. Half of the patient cohort exhibited a reduction in total dendritic cells. Array comparative genomic hybridization (CGH) revealed six patients harboring copy number variations (CNVs) never reported in normal subjects. The gene content of these CNVs was carefully analyzed to understand the mechanisms leading to 22q11.2DS phenocopies. According to these results, we suggested that array-CGH should be used as a first-tier tool for patients resembling 22q11.2DS.

Burosumab for X-linked hypophosphatemia in children and adolescents: Opinion based on early experience in seven European countries.

Given the relatively recent introduction of burosumab in the management of X-linked hypophosphatemia (XLH), there is limited real-world data to guide its use in clinical practice. As a group of European physicians experienced with burosumab treatment in clinical practice, we convened with the objective of sharing these practice-based insights on the use of burosumab in children and adolescents with XLH. We attended two virtual meetings, then discussed key questions via Within3, a virtual online platform. Points of discussion related to patient selection criteria, burosumab starting dose, dose titration and treatment monitoring. Our discussions revealed that criteria for selecting children with XLH varied across Europe from all children above 1 year to only children with overt rickets despite conventional treatment being eligible. We initiated burosumab dosing according to guidance in the Summary of Product Characteristics, an international consensus statement from 2019 and local country guidelines. Dose titration was primarily guided by serum phosphate levels, with some centers also using the ratio of tubular maximum reabsorption of phosphate to glomerular filtration rate (TmP/GFR). We monitored response to burosumab treatment clinically (growth, deformities, bone pain and physical functioning), radiologically (rickets and deformities) and biochemically (serum phosphate, alkaline phosphatase, 1,25-dihydroxyvitamin D, 25-hydroxyvitamin D, urine calcium-creatinine ratio and TmP/GFR). Key suggestions made by our group were initiation of burosumab treatment in children as early as possible, from the age of 1 year, particularly in those with profound rickets, and a need for clinical studies on continuation of burosumab throughout adolescence and into adulthood.

Disorders/Differences of Sex Development Presenting in the Newborn With 46,XY Karyotype.

Differences/disorders of sex development (DSD) are a heterogeneous group of congenital conditions, resulting in discordance between an individual's sex chromosomes, gonads, and/or anatomic sex. The management of a newborn with suspected 46,XY DSD remains challenging. Newborns with 46,XY DSD may present with several phenotypes ranging from babies with atypical genitalia or girls with inguinal herniae to boys with micropenis and cryptorchidism. A mismatch between prenatal karyotype and female phenotype is an increasing reason for presentation. Gender assignment should be avoided prior to expert evaluation and possibly until molecular diagnosis. The classic diagnostic approach is time and cost-consuming. Today, a different approach may be considered. The first line of investigations must exclude rare life-threatening diseases related to salt wasting crises. Then, the new genetic tests should be performed, yielding increased diagnostic performance. Focused imaging or endocrine studies should be performed on the basis of genetic results in order to reduce repeated and invasive investigations for a small baby. The challenge for health professionals will lie in integrating specific genetic information with better defined clinical and endocrine phenotypes and in terms of long-term evolution. Such advances will permit optimization of counseling of parents and sex assignment. In this regard, society has significantly changed its attitude to the acceptance and expansion beyond strict binary male and female sexes, at least in some countries or cultures. These management advances should result in better personalized care and better long-term quality of life of babies born with 46,XY DSD.

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.

Pulp chamber features, prevalence of abscesses, disease severity, and PHEX mutation in X-linked hypophosphatemic rickets.

INTRODUCTION: Rickets, growth failure, and recurrent periapical abscesses with fistulae are main signs in patients with X-linked hypophosphatemic rickets (XLH). Prevalence of abscesses, pulp chamber features, biochemical findings, disease severity, and PHEX gene mutation were examined. MATERIALS AND METHODS: Pulp chambers size, shape, and morphology were assessed by orthopantomography in XLH patients (n = 24, age 5.8 ± 1.6 years) and in sex and age-matched healthy controls (n = 23, age 6.2 ± 1.4 years). XLH patients received conventional treatment (3.5 ± 1.9 years). Pulp chamber features were assessed in teeth of primary dentition and in the permanent left mandibular first molar and compared with those of controls. Rickets severity score was assessed at wrist, knee, and ankle. RESULTS: The mean pulp chamber area/tooth area ratio, mean pulp chamber height/pulp chamber width ratio, and prominence of pulp horns into the tooth crown in primary and secondary molars were significantly higher in patients than in controls and in patients suffered abscesses than in patients without abscesses. Sixteen patients (67%) had a history of abscesses; incisors were affected more than canines and molars. Severity of rickets and mean serum parathyroid hormone (PTH) levels were significantly higher, and mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] levels significantly lower in patients suffered abscesses than in patients without abscesses. PHEX gene mutations were not correlated with dental phenotype and disease severity. CONCLUSION: Enlarged pulp chambers with altered shape and morphology affected the majority of XLH patients predisposing to recurrent periapical abscesses with fistulae. Dental phenotype was associated with severity of rickets, high serum PTH, and low serum 1,25(OH)2D levels.

Acute dacryocystitis with giant lacrimal abscess: a case report.

BACKGROUND: We report a case of a 4-year-old girl with acute dacryocystitis complicated with giant lacrimal abscess who underwent open dacryocystectomy as resolutive surgery. CASE PRESENTATION: A 4-year-old previously healthy girl presented to the emergency department with a voluminous and erythematous, fluctuant warm mass localized inferiorly to the medial canthus of the right eye. She had a 2-week history of right inferior eyelid oedema and hyperemia, treated firstly with dexamethasone and netilmicin by eye drops, and then with per oral amoxicillin clavulanate. Ultrasound examination showed a well-circumscribed round lesion filled by anechoic fluid with punctate echoes, confirming a diagnosis of acute dacryocystitis complicated by lacrimal abscess. Parents refused a head CT. Systemic antibiotic treatment was started and, on 5th day from admission, open dacryocystectomy was performed with good esthetical result. CONCLUSIONS: Pediatric acute dacryocystitis is a potentially serious condition, which must be treated with intravenous antibiotic therapy followed by surgery tailored to the clinical history. Even if probing and dacryocystorhinostomy are the most used surgery in adults and children, open dacryocystectomy is a safe and successful option, mainly in severe cases where imaging studies are not available.

Paternity in 5α-Reductase-2 Deficiency: Report of Two Brothers with Spontaneous or Assisted Fertility and Literature Review.

Fertility remains a challenge for men with 5α-reductase-2 deficiency. Such a diagnosis was made in 2 adult brothers who are compound heterozygous for the 5α-reductase type 2 gene (SRD5A2; c.308G>C; c.689A>C). They were born with ambiguous genitalia and the male sex was assigned. Both brothers underwent reconstructive genital surgery during pediatric age and had spontaneous virilization at puberty. The older brother experienced natural conception, while the younger had a son by assisted reproductive technology. Other family members were demonstrated to be compound heterozygous or heterozygous for the same genetic variants. The older brother is the third man with 5α-reductase-2 deficiency and spontaneous paternity. The little series of men with 5α-reductase-2 deficiency and documented spontaneous or assisted paternity is reviewed. In conclusion, the possibility of fatherhood is a main indication for male sex assignment in patients with 5α-reductase-2 deficiency.

Triptorelin depot for the treatment of children 2 years and older with central precocious puberty.

INTRODUCTION: Triptorelin depot is largely used to treat central precocious puberty (CPP) in children. Areas covered: This review updates triptorelin depot treatment of CPP, focusing on trials that compared 3.75 mg/28 day treated and untreated children till the adult height (AH). Efficacy of the new 11.25 mg/90 days or 22.5 mg/6 month formulations in suppressing pituitary-gonadal axis in short-term trials is also addressed. Short- and long-term safety was summarized. Expert commentary: Long experience on triptorelin depot use in children with CPP is available. Outcome differences on AH are reported; they may be due to heterogenicity of treated patients; some items remain to be optimized. No long term-adverse events on reproductive function are reported; additional studies would clarify if CPP per sè or triptorelin depot administration may increase hyperandrogenism and/or polycystic ovary syndrome risk in adulthood. The quarterly formulation seems to be able to suppress pituitary-gonadal axis and pubertal development and to determine similar end-results as monthly formulation, but additional trials are needed. Few data are available for the 22.5 mg/6 month formulation. Triptorelin depot treatment of CPP should be restricted to tertiary pediatric endocrinology centers, considering that some uncertainties still exist and that rare but serious adverse events may occur.

Novel Familial Variant of the Desert Hedgehog Gene: Clinical Findings in Two Sisters with 46,XY Gonadal Dysgenesis or 46,XX Karyotype and Literature Review.

BACKGROUND: In humans, Desert Hedgehog (DHH) gene mutations are a very rare cause of 46,XY gonadal dysgenesis (GD), eventually associated with peripheral neuropathy. PATIENTS AND METHODS: Clinical records of 12 patients with 46,XY GD and unknown genetic background were reviewed and a 46,XY woman with peripheral neuropathy was individuated. Her 46,XX sister affected by similar neuropathy was also investigated. Genomic DNA was extracted and DHH exons sequenced and analyzed. A comparative genomic hybridization array was also performed. RESULTS: In both the 46,XY and 46,XX sisters, a homozygous c.554C>A mutation in exon 2 of the DHH gene was found, determining a premature termination codon (p.Ser 185*). Heterozygous consanguineous carrier parents showed neither reproductive problems nor peripheral neuropathy. In the proband and her sister, a 499-kb duplication in 9p22.1 was also found. CONCLUSION: A 46,XY European woman with 46,XY GD and a novel homozygous DHH pathogenic variant is reported, confirming that this gene plays a key role in male gonadal development. Her 46,XX sister, harboring the same mutation, showed normal internal and external female phenotype. Thus, DHH seems not to be involved in the ovarian development pathway or its postpubertal function. Homozygous DHH mutations cause a specific peripheral neuropathy in humans with both 46,XY and 46,XX karyotypes.

Human Chorionic Gonadotropin Test: Old Uncertainties, New Perspectives, and Value in 46,XY Disorders of Sex Development.

The human chorionic gonadotropin (hCG) test represents a key step in assessing Leydig cell function in prepubertal males, but differences in terms of hCG doses, number of injections, and sequence of blood drawing are published in the literature, showing poor standardization. The few available data in healthy boys are summarized here. A recombinant hCG (rhCG) formulation might permit overcoming some controversies as well as avoid the potential biological risk related to the injection of extractive hormones. Studies in humans are scarce, but they indicate that 250 µg rhCG in a single dose may represent a useful scheme for the dynamic evaluation of Leydig cell function in children as well as in adults. The main indication for hCG testing in childhood is the investigation of 46,XY disorders of sex differentiation. The test must also be considered in order to investigate the presence of functional testicular tissue when gonadal peptide hormones cannot be measured.

Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease.

Camurati-Engelmann disease (CED) is an ultrarare autosomal dominant bone dysplasia. Cortical thickening of the diaphyses of the long bones with narrowing of the medullary cavity are associated with bone pain, waddling gait, muscular weakness, easy fatigability, and a marfanoid body habitus. There is no specific treatment for CED. Nonsteroidal anti-inflammatory drugs or glucocorticoids are ineffective in improving bone lesions. A family with a mild to severe form of CED is described. Two patients received long-term bisphosphonate treatment: the 19-year-old female proband was treated with zoledronic acid for 2.2 years; the 4-year-old male proband was treated with neridronic acid for 16 months and with zoledronic acid for an additional 18 months. In both probands, zoledronic acid treatment significantly improved the clinical symptoms, bone lesions, ambulation, and body habitus. Before treatment, both probands showed a marked increase in serum levels of osteocalcin, procollagen type I N-terminal propeptide, and cross-linked carboxyterminal telopeptide of type I collagen, reflecting an increased bone turnover. Bone marker levels returned to their normal values during treatment. Zoledronic acid treatment may be an important therapeutic option in patients with severe CED. Biochemical markers of bone turnover could be considered as surrogate indexes of CED activity.

Bone Mineral Density in Women Living with Complete Androgen Insensitivity Syndrome and Intact Testes or Removed Gonads.

Complete androgen insensitivity syndrome (CAIS) is due to complete androgen resistance in androgen-dependent tissues. Since androgens are involved in growth, development, and mass maintenance of the skeleton, bone health may be a relevant clinical issue for improving quality of life of women living with CAIS. Bone mineral density (BMD) in women with CAIS and intact gonads has been reported in a normal range, although exceptions are known showing a low BMD mainly at the lumbar level. In women with CAIS and removed gonads, BMD is usually reduced at both the lumbar spine and femoral neck. However, the fracture risk remains largely unknown. In women with CAIS, hormonal replacement therapy may improve BMD, but it does not normalize it. Several factors may be operative (e.g., loss of AR signaling at the bone level, gonadal removal, and age at surgery [before or after attainment of the peak bone mass], inadequate sex steroid replacement therapy, poor compliance with hormonal treatment, high serum FSH levels, lack of testicular protein hormones after gonadal removal), but they are poorly evaluated. In conclusion, the maintenance of testes may represent a strategy to improve bone health in women with CAIS, but a strict follow-up to monitor the cancer risk is mandatory mainly from their 20s onwards. Optimal sex steroid substitutive therapy in adolescence and adulthood is a key factor to improve BMD status in women with CAIS and removed gonads, but conclusive data on optimal management are lacking.

Adult height after spontaneous pubertal growth or GnRH analog treatment in girls with early puberty: a meta-analysis.

Early puberty (EP) has been defined as the onset of puberty in the low-normal range; it may be a cause for concern regarding a possible impairment of adult height (AH). This paper meta-analysed data on AH after spontaneous growth or after gonadotropin-releasing hormone (GnRH) analog treatment in girls with EP. A computerized literature search was conducted from 1980 to June 30, 2016. Only published studies in English were considered. Eight papers were selected (483 cases). In untreated girls (n = 300), predicted adult height (PAH) at start of follow-up (-0.559 SDS (95%CI -1.110 to 0.001); P = 0.050) was close to mid-parental height (MPH) (-0.557 SDS (95%CI -0.736 to -0.419); P < 0.0001) and AH (-0.663 SDS (95%CI -0.803 to -0.524); P < 0.0001). In GnRH analog treated girls (n = 183), PAH before the start of treatment was slightly reduced (-0.939 SDS (95%CI -1.401 to -0.477; P < 0.0001) vs MPH (-0.678 SDS (95%CI -0.942 to -0.414); P < 0.0000), but AH (-0.604 SDS (95%CI -0.877 to -0.338); P < 0.0000) was close to MPH. CONCLUSION: Present meta-analysis indicates that girls with EP spontaneously reach their MPH and that GnRH analog treatment does not widely change growth outcome. Differences among the selected studies for definition of EP, inclusion criteria, treatment duration, age at discontinuation of therapy, definition of AH may affect results. What is Known: • Early puberty represents a main cause of consultation in paediatric endocrinology offices due to concerns of both practitioners and parents. • Treatment with GnRH analogs is sometimes attempted with the aim to improve adult height. What is New: • Untreated and GnRH analog treated girls with early puberty reached similar adult height. • Adult height was consistent with mid-parental height in both untreated and GnRH analog treated girls with early puberty.

5α-Reductase-2 Deficiency: Clinical Findings, Endocrine Pitfalls, and Genetic Features in a Large Italian Cohort.

Clinical records (n = 24) with an established diagnosis of 5α-reductase-2 deficiency were reviewed. A previous misdiagnosis was present in about 70% (period from first observation to definitive diagnosis: 9.1 ± 10.8 years), and in 8 children gonadal removal was performed before certain diagnosis. Initial sex assignment was female in 16/24 (67%) and male in 8/24 (33%) cases. After diagnosis, sex re-assignment was performed in 5 babies (4 girls to male sex; 1 boy to female sex). Baseline testosterone/DHT ratio was diagnostic in 6/12 subjects (first months of life n = 4; puberty n = 2), while post-hCG testosterone/DHT ratio was diagnostic in all tested individuals (choosing both the cut-off value 15 or 10). Eighteen different mutations in the steroid-5α-reductase-2 (SRD5A2) gene were identified, 5 of which have never been reported. In conclusion, a time lag exists before the diagnosis of 5α-reductase-2 deficiency is established; sex assignment and gonadal removal may be performed before certain diagnosis. Sex re-assignment is usually female to male, but the contrary may occur. A large variability in clinical phenotypes and genetic mutations was present in this cohort. Accurate endocrine evaluation is recommended in babies possibly affected by 5α-reductase-2 deficiency, since the use of appropriate cut-off values of testosterone/DHT ratio after hCG stimulation may permit to select individuals for SRD5A2 gene analysis. A genotype-phenotype correlation was not found in this study.

Central Precocious Puberty: Adult Height in Girls Treated with Quarterly or Monthly Gonadotropin-Releasing Hormone Analog Triptorelin.

BACKGROUND/AIMS: Treatment with quarterly gonadotropin-releasing hormone (GnRH) analogs may improve compliance and optimize outcome in girls with central precocious puberty (CPP), but long-term comparative data between the new and the monthly formulations are very scarce. METHODS: A group of girls with idiopathic CPP (n = 13; age 7.9 ± 0.6 years) were treated from the beginning with quarterly triptorelin (11.25 mg/90 days) and followed up to the achievement of adult height (AH). A group of girls with idiopathic CPP (n = 12; age 8.0 ± 0.6 years) treated with monthly triptorelin (3.75 mg/28 days) served as controls. RESULTS: The AH (157.1 ± 4.9 cm) of girls treated with quarterly triptorelin was not significantly different from their mid-parental height (159.7 ± 3.8 cm) and significantly increased in comparison with predicted AH (average tables) at the beginning of GnRH analog therapy. The AH of girls treated with quarterly triptorelin was not significantly different in comparison with that of girls treated with the monthly formulation (158.1 ± 6.6 cm; mid-parental height 158.4 ± 5.0 cm). CONCLUSION: Treatment with quarterly triptorelin formulation permitted to achieve an AH adequate for mid-parental height in girls with CPP. Significant differences of AH between girls with CPP treated with quarterly or monthly formulations were not found.

Growth in Boys with 45,X/46,XY Mosaicism: Effect of Growth Hormone Treatment on Statural Growth.

45,X/46,XY mosaicism is a rare sex chromosome disorder of sex development. Short stature is a main feature of boys with this condition. Different causes likely contribute to growth impairment. Growth hormone (GH) has been administered to treat short stature in boys with 45,X/46,XY mosaicism, but conflicting data are available. Here, spontaneous growth patterns as well as short- and long-term follow-up studies during GH therapy in these patients are reviewed. Short- and mid-term data showed an improvement of the growth pattern in GH-treated boys, mainly when hormonal therapy was started early, while long-term follow-up demonstrated similar adult heights in GH-treated and untreated patients. Individual biological factors (e.g. different chromosome constitution, different mosaicism among various tissues, impaired pubertal growth spurt), non-homogeneous GH doses and different ages at start of therapy may contribute to the variable results. Thus, early GH therapy at pharmacological doses may improve the growth pattern of short boys with 45,X/46,XY mosaicism, but data on adult height are disappointing. Evaluation of larger patient samples treated by homogeneous doses and long-term follow-up studies assessing adult height and safety are needed to reach definitive conclusions on GH therapy in boys with 45,X/46,XY mosaicism.

Long-term growth hormone treatment in a boy with 45,X/46,X,idic(Yp) mixed gonadal dysgenesis: comparison with growth pattern of an untreated patient.

BACKGROUND: Mixed gonadal dysgenesis (MGD) is a rare disorder. Short stature is a well known feature of this condition. Although growth hormone (GH) treatment has been suggested to treat growth impairment, conflicting data surround this issue. CASE REPORT: We report on long-term growth hormone (GH) therapy at pharmacological doses (0.33 mg/kg/week) in a boy (age 4.6 years) with MGD [karyotype 45,X/46,X,idic(Yp)]. An untreated boy of similar karyotype and growth delay served as control. The treated boy showed a progressive improvement of stature during GH administration. His height completely normalized after 6.5 years of treatment and he reached his target height centile before puberty onset. In the untreated boy, no improvement of growth pattern was found. CONCLUSIONS: We conclude that short boys with MGD and 45,X/46,X,idic(Yp) karyotype may benefit from early GH therapy at pharmacological doses. Evaluation of larger patient samples and additional follow-up till final height are needed to reach definitive conclusions as to the optimal growth-promoting therapy for this disorder of sex development.