Genotype-phenotype correlations and long-term efficacy of pamidronate therapy in patients with osteogenesis imperfecta

Purpose@#Osteogenesis imperfecta (OI) is a rare bone fragility disorder caused by defects in type 1 collagen biosynthesis. This study investigated the genotype-phenotype correlations and the efficacy of pamidronate therapy in patients with OI in a single academic center. @*Methods@#This study included 24 patients with OI. A clinical scoring system was used to evaluate disorder severity. COL1A1 and COL1A2 genes were analyzed in 13 patients using Sanger sequencing. Genotype-phenotype correlations and the efficacy of pamidronate therapy were analyzed through a retrospective medical chart review. @*Results@#Of the 24 patients, 18 (75%) were classified as type I (12 with type Ia and 6 with type Ib), 2 as type III (8.4%), and 4 as type IV (16.7%). Type Ia patients showed relatively higher lumbar bone mineral density (BMD) standard deviation scores (SDS) and lower clinical scores than those with other types. Seven patients with qualitative mutations had lower lumbar BMD-SDS (P=0.015) and higher clinical scores (P=0.008) than 6 patients with quantitative mutations. The annual fracture frequency and lumbar BMD-SDS improved in patients with qualitative mutations after pamidronate treatment. @*Conclusion@#This study demonstrated that OI patients with qualitative mutations in COL1A1/2 had a more severe phenotype than those with quantitative mutations. Patients with qualitative mutations showed a significant reduction in fracture frequency and an increase in lumbar BMD-SDS after pamidronate treatment. Clinical score and genotype might be helpful for predicting phenotype and response to pamidronate therapy in OI patients.

Clinical Genetic Testing in Children with Kidney Disease

Chronic kidney disease, the presence of structural and functional abnormalities in the kidneys, is associated with a lower quality of life and increased morbidity and mortality in children. Genetic etiologies account for a substantial proportion of pediatric chronic kidney disease. With recent advances in genetic testing techniques, an increasing number of genetic causes of kidney disease continue to be found. Genetic testing is recommended in children with steroid-resistant nephrotic syndrome, congenital malformations of the kidney and urinary tract, cystic disease, or kidney disease with extrarenal manifestations. Diagnostic yields differ according to the category of clinical diagnosis and the choice of test. Here, we review the characteristics of genetic testing modalities and the implications of genetic testing in clinical genetic diagnostics.

Clinical Genetic Testing in Children with Kidney Disease

Chronic kidney disease, the presence of structural and functional abnormalities in the kidneys, is associated with a lower quality of life and increased morbidity and mortality in children. Genetic etiologies account for a substantial proportion of pediatric chronic kidney disease. With recent advances in genetic testing techniques, an increasing number of genetic causes of kidney disease continue to be found. Genetic testing is recommended in children with steroid-resistant nephrotic syndrome, congenital malformations of the kidney and urinary tract, cystic disease, or kidney disease with extrarenal manifestations. Diagnostic yields differ according to the category of clinical diagnosis and the choice of test. Here, we review the characteristics of genetic testing modalities and the implications of genetic testing in clinical genetic diagnostics.

Efficacy of Living Donor Liver Transplantation in Patients with Methylmalonic Acidemia / 대한소아소화기영양학회지

Purpose@#Despite aggressive medical and nutritional management, patients with methylmalonic acidemia (MMA) often suffer from multi-organ damage. Early deceased donor liver transplantation (DDLT) has emerged as an intervention to prevent disease progression. We investigated the efficacy of living donor LT (LDLT) with a potential carrier of MMA and a small volume of graft in patients with MMA as an alternative to DDLT. @*Methods@#Of five patients (three male, two female; median age 5.7 years; range, 1.3–13.7 years), four underwent carrier LDLT, while one underwent non-carrier auxiliary LDLT. All patients received pre- and post-LT continuous renal replacement therapy and were provided with minimal restriction diet according to serum MMA level after LT. MMA levels in the serum and urine, the incidence of metabolic crisis, and clinical findings before and after LT were compared. @*Results@#The survival rate was 100% during 2.2 years of follow up period after LT. In all five cases, MMA titer in the serum after transplantation decreased with less restrictive diet. Metabolic crisis was not observed during the follow-up period. In addition, no patient showed progression of severe renal impairment requiring hemodialysis. Progression of delayed cognitive development was not observed. Social functioning with improved neuropsychiatric development was observed. @*Conclusion@#This study showed that LDLT achieved improved quality of life with less restrictive diet, therefore it could be a feasible alternative option to DDLT for the treatment of patients with MMA, even with an auxiliary LT.

Efficacy of Living Donor Liver Transplantation in Patients with Methylmalonic Acidemia / 대한소아소화기영양학회지

Purpose@#Despite aggressive medical and nutritional management, patients with methylmalonic acidemia (MMA) often suffer from multi-organ damage. Early deceased donor liver transplantation (DDLT) has emerged as an intervention to prevent disease progression. We investigated the efficacy of living donor LT (LDLT) with a potential carrier of MMA and a small volume of graft in patients with MMA as an alternative to DDLT. @*Methods@#Of five patients (three male, two female; median age 5.7 years; range, 1.3–13.7 years), four underwent carrier LDLT, while one underwent non-carrier auxiliary LDLT. All patients received pre- and post-LT continuous renal replacement therapy and were provided with minimal restriction diet according to serum MMA level after LT. MMA levels in the serum and urine, the incidence of metabolic crisis, and clinical findings before and after LT were compared. @*Results@#The survival rate was 100% during 2.2 years of follow up period after LT. In all five cases, MMA titer in the serum after transplantation decreased with less restrictive diet. Metabolic crisis was not observed during the follow-up period. In addition, no patient showed progression of severe renal impairment requiring hemodialysis. Progression of delayed cognitive development was not observed. Social functioning with improved neuropsychiatric development was observed. @*Conclusion@#This study showed that LDLT achieved improved quality of life with less restrictive diet, therefore it could be a feasible alternative option to DDLT for the treatment of patients with MMA, even with an auxiliary LT.

Hypotonia, Ataxia, and Delayed Development Syndrome caused by the EBF3 mutation in a Korean boy with muscle hypotonia

Hypotonia, Ataxia, and Delayed Development Syndrome (HADDS) is an autosomal-dominant, extremely rare neurodevelopmental disorder caused by the heterozygous EBF3 gene mutation. EBF3 is located on chromosome 10q26.3 and acts as a transcription factor that regulates neurogenesis and differentiation. This syndrome is characterized by dysmorphism, cerebellar hypoplasia, urogenital anomaly, hypotonia, ataxia, intellectual deficit, and speech delay. The current report describes a 3-year-old Korean male carrying a de novo EBF3 mutation, c.589A>G (p.Asn197Asp), which was identified by whole exome sequencing. He manifested facial dysmorphism, hypotonia, strabismus, vermis hypoplasia, and urogenital anomalies, including vesicoureteral reflux, cryptorchidism, and areflexic bladder. This is the first report of a case of HADDS cause by an EBF3 mutation in the Korean population.

Hypotonia, Ataxia, and Delayed Development Syndrome caused by the EBF3 mutation in a Korean boy with muscle hypotonia

Hypotonia, Ataxia, and Delayed Development Syndrome (HADDS) is an autosomal-dominant, extremely rare neurodevelopmental disorder caused by the heterozygous EBF3 gene mutation. EBF3 is located on chromosome 10q26.3 and acts as a transcription factor that regulates neurogenesis and differentiation. This syndrome is characterized by dysmorphism, cerebellar hypoplasia, urogenital anomaly, hypotonia, ataxia, intellectual deficit, and speech delay. The current report describes a 3-year-old Korean male carrying a de novo EBF3 mutation, c.589A>G (p.Asn197Asp), which was identified by whole exome sequencing. He manifested facial dysmorphism, hypotonia, strabismus, vermis hypoplasia, and urogenital anomalies, including vesicoureteral reflux, cryptorchidism, and areflexic bladder. This is the first report of a case of HADDS cause by an EBF3 mutation in the Korean population.

Campomelic Dysplasia with Sex Reversal Harboring a Novel Frameshift Mutation

Campomelic dysplasia (CD) is a rare genetic disease characterized by skeletal dysplasia that also affects several other organ systems. CD is caused by a SOX9 mutation. We here report a case of CD with a 46, XY karyotype and female external genitalia. This child was born with a weight of 3.12 kg after 37 weeks of gestation. She exhibited a number of characteristic features including a small thoracic cage, bowing of both femurs, clubbed feet, hypoplastic scapula, 11 pairs of ribs, a bell-shaped narrow thorax, micrognathia, macroglossia, a cleft palate, a flattened nasal bridge, and low set ears. She experienced additional distress because of the presence of a tracheal ring and because she had tracheomalacia. CD was diagnosed through nucleotide sequence analysis. A frameshift mutation, c.235delC (p.Gln79Argfs*31), was identified in the SOX9 gene that has not previously been reported.

Psychological characteristics of adult neurofibromatosis type 1 patients seeking elective surgery

Background@#Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder involving the nervous system characterized by the development of neurofibromas throughout the body. Patients with NF1 are also known to have cognitive, behavioral, social, and emotional problems. Using the Symptom Checklist-90-Revision (SCL-90-R) questionnaire, we aimed to assess the psychological characteristics of NF1 patients seeking surgery at a tertiary hospital. @*Methods@#Adult NF1 patients visiting a plastic surgery outpatient clinic between March 2018 and March 2020 were enrolled in this study. The presence and intensity of psychopathological symptoms were assessed using 10 domains, including the General Severity Index (GSI). Standard T-scores were used to compare the results to population-based norms. The impact of demographic factors was also analyzed. @*Results@#In total, 65 patients were included in the study. The mean GSI of all patients was 43.7, and the mean score of the other nine domains was 45.3. No scores deviated from the population-based normal ranges. Nonetheless, women had significantly higher mean T-scores than men in a few domains, including the GSI, obsessive-compulsive disorder, depression, and anxiety. Most of the other characteristics, such as age, education, marital status, family history, and tumor site did not have significant effects. @*Conclusions@#Adult NF1 patients who visit plastic surgery clinics for elective surgery have psychopathological characteristics that do not differ from the general population according to the SCL-90-R. The results of this study can be considered in consultations with these patients.

A Novel COL4A1 Mutation in a Neonate with Intrauterine Intraventricular Hemorrhage and Porencephaly

Collagen type IV alpha 1 (COL4A1) plays an important role in construction of the basement membranes of all human tissues, especially vessels. Mutations in COL4A1 lead to various multisystemic dysfunctions, including hereditary porencephaly, hemorrhagic stroke, hemiplegia, cerebral small vessel disease, and nephropathy. In this study, we describe a neonatal case featuring a novel de novo COL4A1 mutation, manifesting as fetal intraventricular hemorrhage and porencephaly. This patient is one of the youngest to have been diagnosed with the most severe phenotype. Our experience may assist clinicians in the diagnosis and management of this extremely rare genetic condition.

Beckwith-Wiedemann Syndrome and Jacobsen Syndrome Caused by 11pter Duplication and 11qter Deletion Inherited from Paternal Pericentric Inversion

We report a case of Beckwith-Wiedemann syndrome (BWS) and Jacobsen syndrome (JBS) due to 11pter trisomy and 11qter monosomy caused by paternal inv(11)(p15.1q24.2). The patient was born premature and had a variety of clinical features including characteristic facial dysmorphism, cardiac abnormalities, and thrombocytopenia. The karyotype was described as 46,XX,rec(11)dup(11p)inv(11)(p15.1q24.2)pat and methylation-specific multiplex ligation-dependent probe amplification analysis showed duplication of the 11p15.5 region and hypermethylation of imprinting center 1. Chromosomal microarray analysis demonstrated 23.8 Mb duplication on 11pter-p14.3 and 13.8 Mb deletion on 11q23.3-qter. These results were consistent with BWS and JBS, respectively. Because uniparental disomy inherited from paternal pericentric inversion results in simultaneous 11p15.5 duplication and 11q23.3 deletion, appropriate genetic tests are necessary for accurate genetic diagnosis of patients.

Psychological Impact of Quarantine on Caregivers at a Children's Hospital for Contact with Case of COVID-19

Quarantine often provokes negative psychological consequences. Thus, we aimed to identify the psychological and behavioral responses and stressors of caregivers quarantined with young patients after a close contact to a coronavirus disease 2019 case at a children's hospital. More than 90% of the caregivers reported feelings of worry and nervousness, while some of them reported suicidal ideations (4.2%), and/or homicidal ideations (1.4%). Fear of infection of the patient (91.7%) and/or oneself (86.1%) were most frequently reported stressors. A multidisciplinary team including infection control team, pediatrician, psychiatrist, nursing staff and legal department provided supplies and services to reduce caregiver's psychological distress. Psychotropic medication was needed in five (6.9%), one of whom was admitted to the psychiatry department due to suicidality. Quarantine at a children's hospital makes notable psychological impacts on the caregivers and a multidisciplinary approach is required.

Campomelic Dysplasia with Sex Reversal Harboring a Novel Frameshift Mutation

Campomelic dysplasia (CD) is a rare genetic disease characterized by skeletal dysplasia that also affects several other organ systems. CD is caused by a SOX9 mutation. We here report a case of CD with a 46, XY karyotype and female external genitalia. This child was born with a weight of 3.12 kg after 37 weeks of gestation. She exhibited a number of characteristic features including a small thoracic cage, bowing of both femurs, clubbed feet, hypoplastic scapula, 11 pairs of ribs, a bell-shaped narrow thorax, micrognathia, macroglossia, a cleft palate, a flattened nasal bridge, and low set ears. She experienced additional distress because of the presence of a tracheal ring and because she had tracheomalacia. CD was diagnosed through nucleotide sequence analysis. A frameshift mutation, c.235delC (p.Gln79Argfs*31), was identified in the SOX9 gene that has not previously been reported.

Chylous Manifestations and Management of Gorham-Stout Syndrome

Gorham-Stout disease (GSD) was first described by Gorham and colleagues in 1954, but its precise mechanism and cause remain to be elucidated. In this condition, voluminous and potentially fatal chylous effusions into the thorax can occur. Herein, we describe a case of GSD in which the patient presented with massive pleural effusions and mottled osteolytic bone lesions. We performed multiple operations, including thoracic duct ligation using video-assisted thoracoscopic surgery and thoracotomic decortication, but these procedures did not succeed in preventing recurrent pleural effusion and chest wall lymphedema. After administering sirolimus (0.8 mg/m2, twice a day) and propranolol (40 mg, twice a day), the process of GSD in this patient has been controlled for more than 2 years.

Identification of Potocki–Lupski syndrome in patients with developmental delay and growth failure

PURPOSE@#Potocki–Lupski syndrome (PTLS), is a recently identified, rare genomic disorder. The patients are affected by infantile hypotonia, poor growth and developmental delay. Facial dysmorphism may not be obvious in some patients. PTLS is associated with microduplication at chromosome 17p11.2. In the current study, three Korean patients are reported with their clinical and genetic features.@*MATERIALS AND METHODS@#The clinical findings of each patient were reviewed. Karyotyping and multiplex ligation-dependent probe amplification (MLPA) analyses were done for genetic diagnoses.@*RESULTS@#All the patients did not have the characteristic dysmorphic features, such as broad forehead, triangular face, asymmetric smile and palpebral fissures. On the other hand, all three patients were affected by variable degree of developmental delay, poor oral intake, failure to thrive, and language development disorders. Chromosome 17p11.2 duplication was identified by conventional karyotyping analysis only in one patient, whereas the other confirmed by MLPA analyses.@*CONCLUSION@#Delayed development was mostly commonly observed in our patients without distinct dysmorphic facial features. In this respect, genomic screening in patients with developmental delay would identify more cases with PTLS to understand their long-term clinical courses with the development of adequate psychological and rehabilitation education program.

Adrenal Cortical Neoplasm with Uncertain Malignant Potential Arising in the Heterotopic Adrenal Cortex in the Liver of a Patient with Beckwith-Wiedemann Syndrome

Patients with Beckwith-Wiedemann syndrome (BWS) are predisposed to developing embryonal tumors, with hepatoblastoma being the most common type. Our patient showed hemihypertrophy, macroglossia, and paternal uniparental disomy in chromosome 11 and was diagnosed with BWS. When the patient was 9 months old, a 2.5×1.5 cm oval hypoechoic exophytic mass was detected in the inferior tip of his right liver. Preoperative imaging identified it as hepatoblastoma; however, histologic, immunohistochemistry, and electron microscopic findings were compatible with adrenal cortical neoplasm with uncertain malignant potential. The origin of the adrenal tissue seemed to be heterotopic. Here, we describe for the first time an adrenal cortical neoplasm with uncertain malignant potential arising in the heterotopic adrenal cortex located in the liver of a patient with BWS.

Novel ATP8B1 Gene Mutations in a Child with Progressive Familial Intrahepatic Cholestasis Type 1 / 대한소아소화기영양학회지

Progressive familial intrahepatic cholestasis (PFIC) is a group of severe genetic disorders, inherited in an autosomal recessive manner, causing cholestasis of hepatocellular origin, later progressing to biliary cirrhosis and liver failure. This is the first report of PFIC type 1 with novel compound heterozygous mutations in Korea. The patient was presented with intrahepatic cholestasis, a normal level of serum γ-glutamyl transferase, steatorrhea, and growth failure. Genetic testing of this patient revealed novel compound heterozygous mutations (p.Glu585Ter and p.Leu749Pro) in the ATP8B1 gene. After a liver transplantation at age 19 months, the patient developed severe post-transplant steatohepatitis.

Chylous Manifestations and Management of Gorham-Stout Syndrome / 대한흉부외과학회지

Gorham-Stout disease (GSD) was first described by Gorham and colleagues in 1954, but its precise mechanism and cause remain to be elucidated. In this condition, voluminous and potentially fatal chylous effusions into the thorax can occur. Herein, we describe a case of GSD in which the patient presented with massive pleural effusions and mottled osteolytic bone lesions. We performed multiple operations, including thoracic duct ligation using video-assisted thoracoscopic surgery and thoracotomic decortication, but these procedures did not succeed in preventing recurrent pleural effusion and chest wall lymphedema. After administering sirolimus (0.8 mg/m2, twice a day) and propranolol (40 mg, twice a day), the process of GSD in this patient has been controlled for more than 2 years.

Noonan syndrome and RASopathies: Clinical features, diagnosis and management

Noonan syndrome (NS) and NS-related disorders (cardio-facio-cutaneous syndrome, Costello syndrome, NS with multiple lentigines, or LEOPARD [lentigines, ECG conduction abnormalities, ocular hypertelorism, pulmonic stenosis, abnormal genitalia, retardation of growth and sensory neural deafness] syndrome) are collectively named as RASopathies. Clinical presentations are similar, featured with typical facial features, short stature, intellectual disability, ectodermal abnormalities, congenital heart diseases, chest & skeletal deformity and delayed puberty. During past decades, molecular etiologies of RASopathies have been growingly discovered. The functional perturbations of the RAS-mitogen-activated protein kinase pathway are resulted from the mutation of more than 20 genes (PTPN11, SOS1, RAF1, SHOC2, BRAF, KRAS, NRAS, HRAS, MEK1, MEK2, CBL, SOS2, RIT, RRAS, RASA2, SPRY1, LZTR1, MAP3K8, MYST4, A2ML1, RRAS2). The PTPN11 (40–50%), SOS1 (10–20%), RAF1 (3–17%), and RIT1 (5–9%) mutations are common in NS patients. In this review, the constellation of overlapping clinical features of RASopathies will be described based on genotype as well as their differential diagnostic points and management.

An ANKRD11 exonic deletion accompanied by a congenital megacolon in an infant with KBG syndrome

KBG syndrome is an autosomal dominant syndrome presenting with macrodontia, distinctive facial features, skeletal anomalies, and neurological problems caused by mutations in the ankyrin repeat domain 11 (ANKRD11) gene. The diagnosis of KBG is difficult in very young infants as the characteristic macrodontia and typical facial features are not obvious. The youngest patient diagnosed to date was almost one year of age. We here describe a 2-month-old Korean boy with distinctive craniofacial features but without any evidence of macrodontia due to his very early age. He also had a congenital megacolon without ganglion cells in the rectum. A de novo deletion of exons 5–9 of the ANKRD11 gene was identified in this patient by exome sequencing and real-time genomic polymerase chain reaction. As ANKRD11 is involved in the development of myenteric plexus, a bowel movement disorder including a congenital megacolon is not surprising in a patient with KBG syndrome and has possibly been overlooked in past cases.