1.Clinical and genetic analysis of children with Silver-Russell syndrome.
Liming ZHANG ; Guimei PAN ; Dongxia FU ; Xue WU ; Yongxing CHEN
Chinese Journal of Medical Genetics 2026;43(4):259-264
OBJECTIVE:
To summarize the clinical and genetic characteristics of children with Silver-Russell syndrome (SRS) and improve the recognition of this disease.
METHODS:
A retrospective analysis was conducted on the clinical manifestations and genetic testing results of 29 children with SRS diagnosed at the Children's Hospital Affiliated to Zhengzhou University between March 2016 and June 2025.
RESULTS:
The 29 children had included 18 boys and 11 girls, with the age ranging from 2 months to 16 years. Their primary clinical manifestations included postnatal growth retardation (100%), small for gestational age (SGA) (100%), characteristic facial features (90%), limb asymmetry (83%), feeding difficulties (76%), ulnar deviation of the fifth finger (69%), body mass index (BMI) of < -2 SD (62%), and abnormal bone age (55%), including 15 cases with delayed bone age for an average of 1.5 years and 1 case with advanced bone age for 2.5 years. Additional manifestations included abnormal sexual development in 11 cases (38%), dental malocclusion in 11 cases (38%), allergic diseases in 10 cases (34%), cardiac diseases in 9 cases (31%), skeletal abnormalities in 7 cases (24%), renal hypoplasia in 5 cases (17%), and abnormal cranial MRI findings in 5 cases (17%). Twenty children were treated with recombinant human growth hormone (rhGH) at a dose of 0.1 ~ 0.15 U/(kg.d). Among them, 7 cases achieved annual height increase of ≥ 10 cm, 11 cases achieved annual height increase of ≥ 5 ~ 9 cm, and 2 cases achieved annual height increase < 5 cm. Twenty three children exhibited hypomethylation of imprinted genes in the chromosome region of 11p15, 4 presented maternal uniparental disomy of chromosome 7 [UPD(7)mat], and 2 had harbored nonsense variants of the HMGA2 gene.
CONCLUSION
SRS patients may present with diverse clinical manifestations including postnatal growth retardation, SGA, characteristic facial features, limb asymmetry, feeding difficulties, and ulnar deviation of the fifth finger. Most patients may exhibit abnormal methylation in the 11p15 region. rhGH therapy can improve the height of these patients.
Humans
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Silver-Russell Syndrome/diagnosis*
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Male
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Female
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Child
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Child, Preschool
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Infant
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Adolescent
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Retrospective Studies
2.Clinical, metabolic, and autoimmune characteristics of newly diagnosed young Filipino adults with diabetes mellitus.
Elizabeth Paz-Pacheco ; Angelique Bea C. Uy ; Angelique Love Tiglao-Gica ; Anna Elvira S. Arcellana ; Aura Bree Dayo-Lacdao ; Cynthia P. Cordero ; Cecilia A. Jimeno ; Ma. Cecille Añ ; onuevo-Cruz ; Noel R. Juban
Acta Medica Philippina 2026;60(2):41-49
OBJECTIVES
In Asia, younger individuals (below age 45) are diagnosed to have type 2 diabetes with increased rates of obesity defined by lower BMI yet with greater visceral adiposity (waist circumference and waisthip ratios). The prevalence data on type 1 diabetes is not well established, considered to be low, but is seen to be increasing as well. This changing phenotype therefore, presents a clinical dilemma in terms of correctly classifying diabetes and deciding on the consequent appropriate treatment. Distinguishing type 1 from type 2 diabetes has become more difficult with type 2 diabetes dramatically increasing in young adults and children. This study aims to define the characteristics of diabetes among young adults in the Philippines to provide a basis for appropriate management amidst changes in diabetes phenotypes seen globally.
METHODSIn this cross-sectional analytic study, we characterized the demographic, metabolic, and autoimmune features of diabetes among young adult Filipinos aged 18 to 45 years old consulting at a tertiary referral center in Manila, Philippines. Baseline serum A1c, FBS, 75-g oral glucose tolerance test, insulin, serum C-peptide, insulin autoantibodies, leptin, adiponectin, lipid profile, and thyroid function tests were obtained from the participants and analyzed. The homeostasis model assessment (HOMA) was used to estimate the insulin sensitivity.
RESULTSA total of 348 patients with diabetes were included, with females comprising two-thirds of the participants. The mean age at diagnosis of diabetes was 35.9±7.22 years. The mean BMI was 28.12 kg/m2, with median waist to hip ratio (WHR) of 0·93. Metabolic syndrome was found in 60% of participants and 67.82% were obese by body mass index. The mean A1c was 9.07±2.52%. Good glucose control (A1c less than 7.0%) was seen in 23% of participants while nearly half (48%) had HbA1c which was >9.0%. The median levels of fasting insulin and C-peptide were 12.62 (range 1.33–90.42) mIU/L and 0.78 ng/mL (range 0–16.2), respectively.
Included participants were diagnosed with diabetes within a year and as such, majority did not have any micro- or macrovascular complications. The most common diabetes complication was sensory neuropathy detected by monofilament testing, which was found in 28% of participants, followed by non-proliferative diabetic retinopathy in 13%. A history of previous diabetic ketoacidosis was found in 10 patients (2.87%). Glutamic acid decarboxylase (GAD) and insulin auto-antibodies were found in 3.2% and 19.3% of participants, respectively. Approximately half (51.73%) of the participants were insulin resistant by HOMA-IR.
CONCLUSIONIn contrast with Caucasians and other Asians, diabetes among young Filipino adults is associated with lower BMI but with a similarly high visceral adiposity as shown by an elevated WHR. Metabolic syndrome with insulin resistance as defined by a variety of indices is predominant. Type 1 diabetes with autoantibodies occur in only a small fraction of this population. Data derived from this work can provide a framework for cluster analysis towards personalized management specific to this population.
Human ; Acids ; Adiponectin ; Adiposity ; Adult ; Aged ; Antibodies ; Asia ; Asian ; Asian Continental Ancestry Group ; Autoantibodies ; Body Mass Index ; C-peptide ; Carboxy-lyases ; Child ; Cluster Analysis ; Demography ; Diabetes Complications ; Diabetes Mellitus ; Diabetes Mellitus, Type 1 ; Diabetes Mellitus, Type 2 ; Diabetic Ketoacidosis ; Diabetic Retinopathy ; Diagnosis ; Fasting ; Female ; Glucose ; Glucose Tolerance Test ; Glutamate Decarboxylase ; Glutamic Acid ; Insulin ; Insulin Resistance ; Ketosis ; Leptin ; Lipids ; Metabolic Syndrome ; Obesity ; Patients ; Peptides ; Phenotype ; Philippines ; Population ; Prevalence ; Serum ; Therapeutics ; Thyroid Gland ; Thyroid Function Tests ; Young Adult
3.Medical Management of Paediatric Cushing Syndrome Presenting with Severe Hypercortisolism
Yee Lin Lee ; Chun Jie Lee ; Tzer Hwu Ting ; Ooi Chuan Ng
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):133-
Introduction:
Endogenous Cushing syndrome is a rare manifestation of chronic cortisol excess. It may present with severe hypercortisolism complicated by life-threatening opportunistic infections. Surgical management of a cortisol-secreting tumor is
the mainstay of therapy. However, when the source is not found or when surgery is not feasible, medical therapies may be
employed for rapid control of hypercortisolism.
CASE:
A 13-year-old male presented with breathlessness for one day. He also had a cough associated with weight loss, weakness,
and hallucinations for 1 month. On presentation, he was tachypneic and had moon facies, acne, fine moustache, limb
wasting, and pigmented nail beds. He was also hypertensive and developed an episode of seizure during admission.
Investigation results showed severe hypokalemia and lymphopenia. Radiological examination revealed pneumothorax
with multiple lung cavitations and brain tuberculomas. Bronchoalveolar lavage (BAL) was positive for Aspergillus
fumigatus. However, both BAL and CSF PCR and culture for TB were negative. Serum ACTH was 379 pg/mL (0–46), and
morning serum cortisol was 2,948 nmol/L with loss of diurnal rhythm. His 24-hour urine cortisol was 14,252 nmol/24
hour (31.7–282). This is consistent with ACTH-dependent Cushing syndrome. He was started on anti-TB and anti-fungal
treatment. Serum cortisol levels were persistently high while on high-dose intravenous dexamethasone treatment for TB
meningitis. An MRI pituitary and a CT scan thorax, abdomen, and pelvis could not reveal an ACTH-secreting tumor
source. Metyrapone was started and titrated upwards to control the hypercortisolism. Serum cortisol reduced to 200–300
nmol/L after 1 month, and 24-hour urinary cortisol was down to 22.4 nmol/24 hour after 4 months, requiring weaning
of metyrapone doses.
Conclusion
Metyrapone is effective in the rapid control of severe hypercortisolism with life-threatening complications, as illustrated
in this case. However, it warrants careful monitoring and titration.
Child
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Cushing Syndrome
4.A Spectrum of Thyroid Dysfunction in Children with Down Syndrome: A Malaysian Tertiary Centre Experience
Priyadarshini Puvanendran ; Azriyanti Binti Anuar Zaini ; Wan Hanaa Mardhiah Binti Wan Zainuddin
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):136-137
Introduction:
Endocrine abnormalities are frequently observed in
children with Down syndrome, with thyroid dysfunction
being the most common. The distribution and patterns of
thyroid disorders vary between populations.
Methodology:
Retrospective data were collected from the electronic
medical records of children with Down syndrome who
attended the paediatric clinic at University Malaya Medical
Centre from the year 2000 to 2025. Data were analyzed
to determine the frequency and distribution of thyroid
disorders in this cohort.
Results:
The study included 57 patients, the majority of whom were
identified through routine screening (n = 56, 98.2%). Only
one child (1.8%) was diagnosed following a symptomatic
presentation of diarrhea. Within the cohort, 51 patients
were diagnosed with hypothyroidism and six with hyperthyroidism.
Among those with hypothyroidism, the mean TSH was 22.5
mIU/L, with a median age at presentation of 61 days (IQR:
19–211.5). Notably, 25% of the cohort presented within the first 19 days, while the rest presented after 7 months of age.
Of these, 24 cases (47.1%) were transient, with medications
successfully discontinued at a mean age of 4.0 ± 2.13 years.
Only 26 patients underwent thyroid scan, which was
normal except for one case of thyroid agenesis. Imaging
was not performed in others due to early discontinuation
of therapy or loss to follow-up.
All hyperthyroid patients had autoimmune thyroid disease
(4 Graves’ disease, 2 Hashimoto’s thyroiditis) with positive
autoantibodies. The median age at presentation was 5.4
years (IQR: 2.3–10.2).
Conclusion
Screening for thyroid dysfunction successfully identified
almost all cases in patients with Down syndrome.
Notably, patients which hyperthyroidism in this cohort
had co-occurring autoimmune thyroid dysfunction and
demonstrated a significantly earlier age of presentation
compared to the general paediatric population.
Child
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Down Syndrome
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Thyroid Gland
5.A Rare Paediatric Case of AVPR2-Related Nephrogenic Syndrome of Inappropriate Antidiuresis in Penang
Wei Lian Lean ; Raja Aimee Binti Raja Abdullah ; Gaik Siew Ch&rsquo ; ng ; Voon Lee Lim
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):141-
Introduction:
Nephrogenic syndrome of inappropriate antidiuresis
(NSIAD) is an uncommon X-linked genetic condition
marked by euvolemic hyponatremia, which arises from
a gain-of-function mutation in the arginine vasopressin
receptor type 2 (AVPR2) gene. In contrast to the classic
syndrome of inappropriate antidiuretic hormone
secretion (SIADH), NSIAD is characterized by urine
that is inappropriately concentrated even when arginine
vasopressin (AVP) levels are low or undetectable. Failure
to recognize NSIAD may result in recurrent hyponatremia
and neurological morbidity.
Case:
A 2-year-old male was referred to us after recurrent
vomiting and subsequently developed generalized tonicclonic seizures due to hyponatremia (with a sodium level
of 115 mmol/L). He needed sodium replacement through
an intravenous drip of 3% saline and was stabilized with
oral sodium chloride 20%. Urine osmolality was elevated,
serum osmolality remained normal, and copeptin levels
were low. He was discharged after a 10-day hospital stay.
During follow-up, hyponatremia recurred despite his
typical fluid intake of 1,200 mL/day. He was instructed to
limit his fluid intake to 600–700 mL, which successfully
normalized his serum sodium levels. Serum levels of
adrenocorticotropic hormone, the aldosterone-to-renin
ratio, thyroid function tests, and serum cortisol were all
within normal ranges. Plasma AVP was unusually low (4.0
pmol/L). Whole exome sequencing (WES) confirmed a likely
pathogenic hemizygous variant in AVPR2 gene located on
chromosome Xq28, which was inherited from his mother.
He is the only child, born from a non-consanguineous
marriage, with no other significant family medical history.
Conclusion
Nephrogenic syndrome of inappropriate antidiuresis
(NSIAD), is an uncommon, yet clinically significant
condition. This case highlights the importance of considering a broad range of differential diagnoses when a patient presents with hyponatremic seizure. Furthermore,
obtaining a detailed family history is essential to identify
potential hereditary factors that could contribute to the
condition and for genetic counseling.
Child
;
Nephrogenic Syndrome of Inappropriate Antidiuresis
6.Analysis of FBN1 gene mutations in six Chinese pedigrees affected with Marfan syndrome.
Xianhong DING ; Hongliang CHEN ; Yang LU ; Mengyi XU ; Bingjie HU ; Yicheng FANG ; Bo SHEN
Chinese Journal of Medical Genetics 2025;42(1):41-50
OBJECTIVE:
To determine the types of genetic variants in six Chinese pedigrees affected with Marfan syndrome (MFS) and analyze their clinical characteristics and molecular pathogenesis.
METHODS:
Six MFS pedigrees presented at the Taizhou Enze Medical Center (Group) between 2017 and 2022 were selected as the study subjects. Clinical data of pedigrees were retrospectively analyzed. Peripheral blood samples were collected from the probands and their family members for the extraction of genomic DNA. Whole exome sequencing (WES) was carried out. Candidate variants of the FBN1 gene were verified by Sanger sequencing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), pathogenicity of the candidate variants was assessed. AlphaFold3 and PyMOL software were used for homology modeling of the FBN1 protein and analysis of its three-dimensional structure and amino acid sequence conservation. This study was approved by the Medical Ethics Committee of Taizhou Enze Medical Center (Group) (Ethics No. 20231002).
RESULTS:
Cardiovascular system abnormalities were noted in all pedigrees, ocular abnormalities were present in pedigrees 2 and 5, skeletal system abnormalities were presented in pedigrees 1, and 4 to 6. FBN1 gene mutations were identified in all pedigrees, including c.1957_1958dupGT (p.Asp654fs), c.5014T>A (p.Cys1672Ser), c.8135delC (p.Pro2712fs), c.2302G>T (p.Glu768*), c.3473A>G (p.Glu1158Gly) and c.6169C>T (p.Arg2057*), with each involving a different exon. Four variants were rated as pathogenic, one as likely pathogenic, and one as variant of uncertain significance. Among these, c.5014T>A (p.Cys1672Ser), c.1957_1958dupGT (p.Asp654fs), c.8135delC (p.Pro2712fs), and c.2302G>T (p.Glu768*) were unreported previously. Bioinformatic analysis with SIFT and PolyPhen-2 predicted that the c.5014T>A (p.Cys1672Ser) and c.3473A>G (p.Glu1158Gly) variants were deleterious. Protein homologous sequence alignment analysis revealed that the four novel mutation sites are highly conserved across various species. Homology modeling of the FBN1 protein three-dimensional structure indicated that the six variant sites in the amino acid sequence are all close to hydrogen bonds and may alter the secondary and tertiary structures to varying degrees, thereby confirmed the relationship between the variants and MFS.
CONCLUSION
Four novel variants of the FBN1 gene have been discovered in this study, which has enriched the mutational and phenotypic spectrum of MFS and provided a basis for disease diagnosis and genetic counseling.
Adolescent
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Adult
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Child
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Female
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Humans
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Male
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Middle Aged
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Young Adult
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China
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East Asian People/genetics*
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Exome Sequencing
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Fibrillin-1/genetics*
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Marfan Syndrome/genetics*
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Mutation
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Pedigree
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Retrospective Studies
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Adipokines
7.Analysis of clinical characteristics and NF1 gene variants in a child with Neurofibroma-Noonan syndrome.
Pingping WANG ; Lianshu HAN ; Suhong YANG ; Jianmei ZHANG ; Zhanli LIU
Chinese Journal of Medical Genetics 2025;42(4):419-423
OBJECTIVE:
To explore the clinical characteristics and genetic etiology of a child with Neurofibromatosis-Noonan syndrome (NFNS).
METHODS:
A child with NFNS who was treated at the Department of Endocrinology of Hangzhou Children's Hospital in January 2024 was selected as the study subject. Clinical data of the child was collected by retrospective analysis. Peripheral venous blood samples (2 mL each) were collected from the child and his parents. Genomic DNA was extracted, and trio-whole exome sequencing (Trio-WES) of the family was carried out. Sanger sequencing was used to perform family verification on the candidate variants. The identified variants were classified for pathogenicity according to the Standards and Guidelines for the Interpretation of Sequence Variants established by the American College of Medical Genetics and Genomics (ACMG) (hereafter referred to as the "ACMG guidelines"). This study has been approved by the Medical Ethics Committee of Hangzhou Children's Hospital (Ethics No. 2021-06).
RESULTS:
The child was a 7-year and 4-month-old male. He has short stature, numerous café-au-lait spots on the neck and trunk, and special facial features such as a full forehead, wide interpupillary distance, a low nasal bridge, and low-set ears. The results of Trio-WES showed that the he had harbored the NF1 gene c.3773G>T (p.W1258L) mutation, which was verified by Sanger sequencing to be de novo in origin. The NF1 gene was associated with NFNS, which has an autosomal dominant inheritance. According to the ACMG guidelines, this variant was judged to be a likely pathogenic variant (PS2+PM2+PP3+PP2). No pathogenic variant in genes associated with Noonan syndrome, such as PTPN11, SOS1, RAF1, RIT1, and KRAS, was found.
CONCLUSION
The child with NFNS has clinical features such as short stature, special facial features, and café-au-lait spots. The c.3773G>T (p.W1258L) variation in the NF1 gene may be the genetic etiology of the NFNS child in this study. The results of this study has enriched the variation spectrum of the NF1 gene.
Child
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Humans
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Male
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Exome Sequencing
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Mutation
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Neurofibromatosis 1/genetics*
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Neurofibromin 1/genetics*
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Noonan Syndrome/genetics*
8.Analysis of MECP2 gene variants and X chromosome inactivation in four children with Rett syndrome.
Chen WEI ; Rong QIANG ; Wenwen YU
Chinese Journal of Medical Genetics 2025;42(5):568-573
OBJECTIVE:
To investigate the X-chromosome inactivation (XCI) patterns and origin in four children with Rett syndrome (RTT), and to explore the genetic basis of their phenotypic variability.
METHODS:
Four pediatric RTT cases diagnosed at Northwest Women's and Children's Hospital between August 1, 2022 and October 31, 2024 were enrolled. Clinical data were collected, and whole exome sequencing (WES) and Sanger sequencing were performed on the children and their parents to identify pathogenic variants. XCI analysis and linkage studies were conducted to determine the origin of variants and assess skewed XCI. This study was approved by the Medical Ethics Committee of the Northwest Women's and Children's Hospital (Ethics No. 21-036).
RESULTS:
WES and Sanger sequencing revealed that the four children carried the following MECP2 (NM_001110792.2) variants. c.916C>T (p.Arg306Cys), c.842delG (p.G281Afs*20), c.763C>T (p.R255X), and c.686C>T (p.Pro229Leu). The c.916C>T variant was maternally inherited, while the other three were de novo. All four variants have been previously reported: c.916C>T, c.842delG, and c.763C>T were classified as pathogenic, whereas c.686C>T was deemed likely pathogenic. XCI analysis demonstrated skewed inactivation in child 2 and 3 and their mothers, with maternal X-chromosome recombination during gametogenesis observed in child 3. All variants were located on the maternal X chromosome.
CONCLUSION
Skewed XCI is a common pathogenic mechanism in MECP2-related RTT, and MECP2 variants may exhibit a maternal origin bias. Clinical evaluation should incorporate XCI status for comprehensive genetic analysis.
Child
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Humans
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Chromosomes, Human, X/genetics*
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Exome Sequencing
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Methyl-CpG-Binding Protein 2/genetics*
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Mutation
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Rett Syndrome/genetics*
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X Chromosome Inactivation/genetics*
9.Exploration of the pathogenic mechanism of a novel c.661_664dup (p.P222Lfs*60) variant of SOX10 gene.
Huiying LI ; Peipei CHEN ; Pingping LIU ; Shanshan YU ; Xiaodan JIN ; Shuang ZHAO
Chinese Journal of Medical Genetics 2025;42(5):574-578
OBJECTIVE:
To explore the pathogenic mechanism of a child with Waardenburg syndrome type 4C due to a c.661_664dup (p.P222Lfs*60) variant of SOX10 gene through in vitro experiments.
METHODS:
A child diagnosed at the Handan First Hospital was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples were collected from the child and his parents. Following extraction of genomic DNA, trio-whole exome sequencing was carried out. Pathogenicity of candidate variant was determined by bioinformatic analysis and reference to the guidelines from the American College of Medical Genetics and Genomics (ACMG). Candidate variant was verified by Sanger sequencing. Expression plasmids of wild-type SOX10 and the c.661_664dup (p.P222Lfs*60) variant were constructed and transiently transfected into 293T cells to determine the expression at the RNA and protein levels. The 293T cells transiently transfected with the wild-type/mutant SOX10 were treated with 10 ug/mL cycloheximide (CHX) for 0, 4, 8, 24 h, respectively, and the degradation rate of target protein was detected by Western blotting assay. This study has been approved by the Ethics Committee of Handan First Hospital (Ethics No. HDYY-LW-25053).
RESULTS:
The child was found to harbor a heterozygous c.661_664dup (p.P222Lfs*60) variant of the SOX10 gene, which was unreported previously. The variant did not significantly alter the expression of SOX10 at the mRNA level but the protein level. After the CHX treatment, the degradation of mutant SOX10 protein had slowed down.
CONCLUSION
The mutant SOX10 may affect the expression of downstream genes by affecting the degradation rate of its protein product.
Humans
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HEK293 Cells
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Mutation
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SOXE Transcription Factors/metabolism*
;
Waardenburg Syndrome/genetics*
;
Child
10.Clinical characteristics and treatment of two children with Lesch-Nyhan syndrome.
Guang'e YANG ; Conglei SONG ; Fan HE ; Kaili ZHANG ; Bin YANG
Chinese Journal of Medical Genetics 2025;42(6):691-699
OBJECTIVE:
To explore the clinical, genetic, therapeutic and prognostic characteristics of two children with Lesch-Nyhan syndrome (LNS) in order to enhance understanding of this disease and formulate more effective therapeutic strategies.
METHODS:
Clinical data were collected from two children clinically diagnosed with LNS who were treated at Anhui Provincial Children's Hospital from April 2023 to January 2024. Data were retrospectively collected and included clinical manifestations (symptoms, signs, laboratory and imaging findings), treatment course, and results of follow-up. Peripheral venous blood samples were obtained from child 1 and his parents. Whole-exome sequencing (WES) was performed. Candidate variants were validated by Sanger sequencing. Standard bioinformatic analysis of the raw WES data was conducted, including quality control, alignment, variant calling, and annotation. Candidate pathogenic variants were filtered using population frequency databases (e.g., gnomAD), disease databases (e.g., OMIM, ClinVar), and multiple in silico pathogenicity prediction tools (e.g., SIFT, PolyPhen-2, CADD). Phenotype matching was integrated using Human Phenotype Ontology (HPO) terms. Pathogenicity classification of variants was performed according to the American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Interpretation of Sequence Variants (2015). This study was approved by the Medical Ethics Committee of Anhui Children's Hospital, Children's Hospital of Fudan University (Ethics No.: EYLL-2014-027).
RESULTS:
Child 1, a 4-year-old boy, had presented with developmental delay for over 3 years, accompanied by abnormal postures and involuntary lip-biting. Physical examination revealed limb dystonia, anxious expression, lower lip damage, and communication difficulties. Laboratory tests showed hyperuricemia and renal stones. Genetic testing identified a hemizygote variant of the HPRT1 gene, c.135G>T (p.Arg45Ser), inherited from an asymptomatic carrier mother, which confirmed the diagnosis of LNS. This variant was absent from population databases (gnomAD, 1000 Genomes, dbSNP). Protein function prediction tools consistently indicated it as a pathogenic or likely pathogenic variant (SIFT, PolyPhen-2, CADD, and REVEL scores all reached pathogenic thresholds). Protein structural modeling revealed that the variant may disrupt the hydrogen-bonding network compromising the tetramer stability. ACMG classification designated it as likely pathogenic (PM1+PM2_Supporting+PM5+PP3). The patient was treated with benhaxol hydrochloride, baclofen, and clonazepam to improve his neurological symptoms, in addition with treatment with febuxostat from the Nephrology Department to manage his purine metabolism. After one year of follow-up, the patient's abnormal posture showed slight improvement, self-injurious behavior persisted but was managed with protective gloves, blood uric acid levels normalized, and renal stones decreased. Case 2, a 13-year-old boy, was hospitalized to the Nephrology Department due to urinary tract infection. Following successful control of the infection, his limb dystonia has worsened, leading to his transfer to the Neurology Ward. The patient had a history of delayed motor and language development, abnormal postures, and lip-biting self-injurious behavior, with elevated blood uric acid levels, leading to the diagnosis of LNS. His parents had declined genetic testing due to financial constraints. Following discharge, the patient did not adhere to the prescribed medication regimen or attend scheduled outpatient visits. The patient had died by the time of the 4-month follow-up contact.
CONCLUSION
Variants of the HPRT1 gene probably underlay the LNS in the two children, and the HPRT1 is the only known pathogenic gene for LNS. Early genetic diagnosis, strict adherence to multidisciplinary comprehensive treatment, and intensive intervention for self-injurious behaviors are crucial for improving the quality of life and prolonging the survival of children with LNS.
Humans
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Male
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Lesch-Nyhan Syndrome/diagnosis*
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Exome Sequencing
;
Child, Preschool
;
Phenotype
;
Infant
;
Child
;
Female
;
Retrospective Studies
;
Mutation


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