DHX37 Variant is One of Common Genetic Causes in Japanese Patients with Testicular Regression Syndrome / Partial Gonadal Dysgenesis without Müllerian Derivatives.

INTRODUCTION: The testicular regression syndrome (TRS) is a form of differences of sex development (DSD) in which the testes differentiate and function during early embryonic development, but subsequently regress. The clinical phenotype of TRS often overlaps with that of partial gonadal dysgenesis (PGD). Previous studies have demonstrated a causal association between TRS/PGD and heterozygous missense variants of DHX37. METHODS: We enrolled 11 Japanese 46,XY individuals (from 10 families) with TRS/PGD who exhibited undetected or hypoplastic testes, Müllerian duct regression, and low serum testosterone or anti-Müllerian hormone levels. The subjects underwent targeted sequencing of 36 known causative genes for DSD, PCR-based Sanger sequencing of DHX37, or whole exome sequencing. RESULTS: Previously described pathogenic variants or novel nonsense variants (SRY, NR5A1, and DMRT1) were observed in four out of 10 families. Additionally, we identified two heterozygous rare variants of DHX37 in four families: a previously reported pathogenic variant (c.923G>A, p.Arg308Gln) in three and a novel likely pathogenic variant (c.1882A>C, p.Thr628Pro) in one. The external genitalia of patients with the DHX37 variants varied from female-type to male-type without micropenis. Eighty percent of Japanese patients with TRS/PGD had monogenic disorders including DHX37 variant being the most commonly identified (40%). The external or internal genital phenotype of TRS/PGD overlaps between DHX37 variant carriers and others. CONCLUSIONS: DHX37 variant is one of common genetic causes in Japanese patients with TRS/PGD without Müllerian derivatives. Genetic test is helpful in detecting DHX37-related TRS/PGD, because of the phenotypic diversity of the external genitalia in this disorder.

Incidence and Risk Factors for Adrenal Crisis in Pediatric-onset Adrenal Insufficiency: A Prospective Study.

PURPOSE: To determine the incidence and risk factors for adrenal crisis (AC) in patients with pediatric-onset adrenal insufficiency (AI). MATERIALS AND METHODS: This multicenter, prospective cohort study conducted in Japan enrolled patients diagnosed with AI at ≤ 15 years of age. The incidence of AC was calculated as events per person-year (PY), and risk factors for AC were assessed using Poisson regression multivariable analysis. RESULTS: The study population comprised 349 patients (164 male, 185 female) with a total follow-up of 961 PY. The median age at enrollment was 14.3 years (interquartile range [IQR] 8.5-21.2 years), and the median follow-up was 2.8 years (IQR 2.2-3.3 years). Of these patients, 213 (61%) had primary AI and 136 (39%) had secondary AI. Forty-one AC events occurred in 31 patients during the study period. The calculated incidence of AC was 4.27 per 100 PY (95% confidence interval [CI] of 3.15-5.75). Poisson regression analysis identified younger age at enrollment (relative risk [RR] 0.93 [95% CI 0.89-0.97]) and increased number of infections (RR 1.17 [95% CI 1.07-1.27]) as significant risk factors. Female sex (RR 0.99 [95% CI 0.53-1.86]), primary AI (RR 0.65 [95 % CI 0.30-1.41]), or equivalent dosage of hydrocortisone per square meter of body area (RR 1.02 [95% CI 0.96-1.08]) was not a significant risk factor. CONCLUSION: A substantial proportion of patients with pediatric-onset AI experience AC. Younger age and an increased number of infections are independent risk factors for developing AC in these patients.

Fibroblast growth factor 23 levels in cord and peripheral blood during early neonatal period as possible predictors of affected offspring of X-linked hypophosphatemic rickets: report of three female cases from two pedigrees.

OBJECTIVES: The role of serum fibroblast growth factor 23 (FGF23) level in early neonatal period on the diagnosis of X-linked hypophosphatemic rickets (XLH) remains unclear. CASE PRESENTATION: Two female patients from the first pedigree had an affected mother, and the other female from the second pedigree had an affected father. In all three cases, FGF23 levels were high in cord blood and peripheral blood at day 4-5. Additionally, the FGF23 levels considerably increased from birth to day 4-5. We identified a PHEX pathogenic variant and initiated treatment during infancy in each case. CONCLUSIONS: In neonates with a parent diagnosed as PHEX-associated XLH, FGF23 in cord blood and peripheral blood at day 4-5 may be useful markers for predicting the presence of XLH.

Fetal growth restriction and a single umbilical artery are independent predictors of hypospadias during pregnancy.

INTRODUCTION: Little is known about the association between hypospadias and small fetuses, as well as the pathological implications of fetal growth restriction (FGR). Thus, we aimed to investigate the association between hypospadias and small fetuses using a database of fetal ultrasound and obstetric events. METHODS: A cohort of male singleton infants delivered after 22 weeks of gestation at Keio University Hospital between 2013 and 2019 was retrospectively reviewed. FGR was defined according to the Delphi criteria. Logistic regression analysis was performed to identify the significant predictors of hypospadias. Placental pathology was reviewed in cases with hypospadias. RESULTS: Of the 2,040 male infants included in the present study, 23 had hypospadias. The prevalences of a single umbilical artery (SUA), small for gestational age, maternal hypertensive disorders of pregnancy, and a small placenta, were significantly higher in infants with hypospadias. Multiple logistic regression analysis revealed that FGR (odds ratio [OR] = 9.39; 95% confidence interval [CI], 2.50-35.3) and the presence of a SUA (OR = 33.4; 95% CI, 8.00-139.5) were independently and significantly associated with hypospadias. When FGR was stratified by the time of onset, its association with hypospadias was significant regardless of the time of onset. Moreover, placental histological findings suggested that fetal vascular malperfusion might play a role in hypospadias. DISCUSSION: FGR and SUAs are independent prenatal predictors of the development of hypospadias, and fetal vascular malperfusion of the placenta may be involved in the etiology of hypospadias.

Less-Invasive Diagnostic Approaches for Infants with Suspected Differences of Sex Development: A Case Report of a 297-g Neonate with Ambiguous Genitalia.

Less-invasive diagnostic approaches for low-birthweight preterm neonates with suspected differences of sex development have not been established. Herein, we describe our diagnostic approaches for a 297-g neonate with ambiguous genitalia. Using a fiberscope, the external genitalia were inspected in an incubator to minimize the risk of hypothermia and infection. Endotracheal aspirate, collected during routine care, was used for genetic testing to avoid anemia and vital signs fluctuations caused by peripheral blood sampling. Array comparative genomic hybridization indicated a 46,XY karyotype. No pathogenic variants of AR and SRD5A2 were found. Endocrinological data could not be evaluated owing to the absence of reference data. Identification and structural evaluation of the internal genitalia and gonads were difficult. On postnatal day 42, the parents assigned their baby's sex as male. Our less-invasive diagnostic approaches of inspection and genetic testing are useful for management, including sex assignment in extremely low-birthweight preterm neonates with ambiguous genitalia.

Hereditary paraganglioma presenting with atypical symptoms: Case report.

RATIONALE: Paraganglioma (PGL), an extra-adrenal pheochromocytoma, is a rare tumor, especially in children. While hypersecretion of catecholamines causes the classic triad of headaches, palpitations, and profuse sweating, prompt diagnosis is still challenging. PATIENT CONCERNS: For 7 months, an 8-year-old boy complained of polyuria and weight loss, followed by proteinuria and headache for 1 month prior to admission. He was admitted to our hospital due to an afebrile seizure. DIAGNOSIS: His blood pressure remained markedly elevated even after cessation of the convulsion. Magnetic resonance imaging of the brain revealed posterior reversible encephalopathy syndrome. Abdominal computed tomography showed a mass lesion encasing the left renal artery, measuring 41 mm in length along its major axis. The plasma and urine levels of normetanephrine were elevated. Additionally, iodine-123-metaiodobenzylguanidine scintigraphy showed an abnormal uptake in the abdominal mass with no evidence of metastasis. Based on these findings, we tentatively diagnosed him with PGL. INTERVENTION: Substantial alpha- and beta-blocking procedures were performed, followed by a tumor resection and an extended left nephrectomy on day 31 of hospitalization. Pathological findings confirmed the diagnosis of PGL. OUTCOME: The postoperative course was uneventful, and his blood pressure normalized without the use of antihypertensive agents. Genetic testing revealed a known SDHB germline mutation. The same mutation was also detected on his father and paternal grandfather without any history of hypertension or malignant tumor. LESSON: It remains challenging to diagnose pheochromocytoma/paraganglioma (PPGL) promptly because PPGL can present with a variety of symptoms. Preceding symptoms of the presented case might be caused by PGL. Although PPGL is a rare disease, especially in children, it should be considered in differential diagnosis when various unexplained symptoms persist.

Case Report: Prenatal Genetic Counseling to Parents of Fetuses Suspected of Having Ambiguous Genitalia.

The occurrence of fetuses suspected of having ambiguous genitalia will likely increase in the future. Currently, the impact of prenatal genetic counseling on parents' understanding and psychological preparedness has not been addressed. We provided prenatal genetic counseling to parents of two fetuses suspected of ambiguous genitalia. Case 1: At 22 weeks of gestation, swelling of the labia majora, and a clitoris-like structure were noted despite 46,XY detected in amniotic fluid cells. Case 2: At 28 weeks of gestation, bladder exstrophy and a scrotum-like structure were noted. At 32 weeks (Case 1) and 37 weeks (Case 2) of gestation, we shared information with parents regarding the possible difficulty of legal sex assignment at birth, and a scenario for registration of the birth certificate. At birth, both babies presented with ambiguous genitalia. For both cases, the parents remained calm on seeing their baby's genitalia for the first time. After a month, we shared medical information with parents, including karyotype, testosterone production capacity, and surgical schedule. In both cases parents assigned their respective baby's legal sex as male. Several months later, parents were questioned on prenatal genetic counseling. Case 1: Mother, "I was prepared to address our baby's genitalia calmly." Father, "I understood the procedure of legal sex assignment." Case 2: Mother, "Without counseling, I would have been more upset and worried." Father, "We were assured that multidisciplinary experts would support us." Prenatal genetic counseling provides reassurance to parents, who remain informed and emotionally secure throughout the legal sex assignment of their child.

Two novel mutations of COMP in Japanese boys with pseudoachondroplasia.

Mutations in the cartilage oligomeric matrix protein (COMP) gene cause both pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED). Most mutations in COMP are located in the region encoding type 3 thrombospondin like domain (TSP3D). We report two Japanese boys with PSACH who had different novel in-frame deletions in TSP3D. The result recapitulates previous reports in that the in-frame deletions in TSP3D preferentially caused PSACH rather than MED.

Discordant fetal phenotype of hypophosphatasia in two siblings.

Hypophosphatasia (HPP) is an autosomal recessive metabolic disorder with impaired bone mineralization due to mutations in the ALPL gene. The genotype-phenotype correlation of this disorder has been widely described. Here, we present two affected siblings, whose fetal phenotypes were discordant. A 31-year-old Japanese woman, G0P0, was referred to our institution because of fetal micromelia. After obstetric counseling, the pregnancy was terminated at 21 weeks' gestation. Post-mortem radiographs demonstrated severely defective mineralization of the skeleton. The calvarial, spinal, and tubular bones were mostly missing. Only the occipital bones, mandible, clavicles, ribs, one thoracic vertebra, ilia, and tibia were relatively well ossified. The radiological findings suggested lethal HPP. Genetic testing for genomic DNA extracted from the umbilical cord identified compound heterozygous mutations in the ALPL gene (c.532T>C, p.Y178H; c.1559delT, p.Leu520Argfs*86). c.532T>C was a novel variant showing no residual activity of the protein by the functional analysis. The parents were heterozygous carriers. In the next pregnancy, biometric values on fetal ultrasonography at 20 and 26 weeks' gestation were normal. At 34 weeks, however, a small chest and shortening of distal long bones came to attention. The neonate delivered at 41 weeks showed serum ALP of <5U/L. Radiological examination showed only mild thoracic hypoplasia and metaphyseal mineralization defects of the long bones. ALP replacement therapy was introduced shortly after birth, and the neonate was discharged at day 22 without respiratory distress. Awareness of discordant fetal phenotypes in siblings with HPP precludes a diagnostic error, and enables early medical intervention to mildly affected neonates.

Cover Image, Volume 176A, Number 1, January 2018.

The cover image, by Satoru Ikenoue et al., is based on the Clinical Report Discordant fetal phenotype of hypophosphatasia in two siblings, DOI: 10.1002/ajmg.a.38531.

Transient Fanconi syndrome in two preterm infants with hydronephrosis and urinary tract infection.

Type IV renal tubular acidosis is known to occur in obstructive uropathy with urinary tract infection. Fanconi syndrome, however, has not been described in these settings. We report two preterm infants who developed Fanconi syndrome associated with hydronephrosis and urinary tract infection. Patient 1 is a boy with 21 trisomy, bilateral renal hypoplasia and bilateral vesicoureteral reflux delivered at 35 weeks' gestation. At postnatal day 42, he developed Fanconi syndrome after urinary tract infection, which persisted until the surgical correction of vesicoureteral reflux. Patient 2 was delivered at 35 weeks' gestation. At postnatal day 9, he was admitted for severe dehydration. He had phimosis and ultrasonography showed left pelviectasis. Laboratory data were compatible with Fanconi syndrome, which resolved spontaneously after fluid therapy. Subsequently urine culture grew bacteria and treatment for infection and topical corticosteroid for phimosis were performed. DMSA scintigraphy performed later showed left renal scar. Tubular cell stretch, due to vesicoureteral reflux in Patient 1 and phimosis in Patient 2, and urinary tract infection in association with immaturity of tubules are thought to have caused Fanconi syndrome.