A Chinese girl with delayed puberty due to 17α-hydroxylase deficiency: the diagnosis, treatment and monitoring approach.

Summary: 17α-hydroxylase deficiency (17α-OHD) is a rare form of congenital adrenal hyperplasia. We report the case of a teenage girl with 17α-OHD who presented with delayed puberty, hypergonadotropic hypogonadism and hypertension. We illustrate the clinical approach in workup, the subsequent management and monitoring of this rare condition.

Hyperammonemia in a girl who inherited a likely pathogenic variant of the ornithine transcarbamylase gene from her asymptomatic father-A peculiar pattern of X-linked recessive inheritance.

A three-year-old Chinese girl presented with hyperammonemia was diagnosed biochemically and genetically (heterozygous for a novel likely pathogenic missense variant c.476T>A) as having ornithine transcarbamylase (OTC) deficiency, a rare X-linked recessive urea cycle disorders. Extensive family genetic screening eventually revealed paternal gonadosomatic mosaicism.

In-house multiplex ligation-dependent probe amplification assay for citrin deficiency: analytical validation and novel exonic deletions in SLC25A13.

Citrin deficiency is one of the most common inborn errors of metabolism in East Asians, which may manifest as neonatal cholestasis, failure to thrive and dyslipidaemia, or recurrent hyperammonaemic encephalopathy. Its molecular diagnosis requires confirmation of the presence of biallelic pathogenic variants in SLC25A13 gene by sequencing, and analysis for a common insertion IVS16ins3kb. However, patients with compatible biochemical features but only one monoallelic pathogenic variant have remained a diagnostic challenge.

Denosumab versus alendronate in long-term glucocorticoid users: A 12-month randomized controlled trial.

Objectives: To compare the efficacy of denosumab and alendronate on raising spine bone mineral density (BMD) in long-term glucocorticoid (GC) users.

Methods: Adult patients receiving long-term prednisolone (≥2.5 mg/day for ≥1 year) were recruited and randomized to either subcutaneous denosumab (60 mg/6 months) or oral alendronate (70 mg/week).

Toxicity from illegitimate slimming agents - a 10-year case series at a tertiary toxicology laboratory in Hong Kong.

Context: This retrospective case-series study aims to provide an overview of the clinical, biochemical and analytical findings in patients who presented with toxicity related to the use of illegitimate slimming agents in Hong Kong from the perspective of a tertiary referral toxicology laboratory.

Methods: All clinical cases referred to the Hospital Authority Toxicology Reference Laboratory, Hong Kong with clinical suspicion of illegitimate slimming agent-related toxicity between January 2008 and December 2017 were reviewed retrospectively. The use of illegitimate slimming agents included the use of (1) deregistered slimming agents, (2) drug analogues that were not registered drugs, (3) registered drugs not approved for the indication of weight reduction (whether prescribed by a doctor or not), and (4) prescription-only slimming agents without a doctor's prescription.

Case Report: The first probable Hong Kong Chinese case of -related acute recurrent rhabdomyolysis in a boy with two novel variants.

Recurrent rhabdomyolysis is frequently ascribed to fatty acid ß-oxidation defects, mitochondrial respiratory chain disorders and glycogen storage-related diseases. In recent years, autosomal recessive mutations have been identified as a prevailing cause of severe rhabdomyolysis in children in Western countries. We report the first probable Hong Kong Chinese case of recurrent severe rhabdomyolysis in early childhood caused by variants.

Founder Mutation c.1516A>C in KLHL40 Is a Frequent Cause of Nemaline Myopathy With Hyponatremia in Ethnic Chinese.

KLHL40-related nemaline myopathy is a severe autosomal recessive muscle disorder. The current study describes 4 cases of KLHL40-related nemaline myopathy in Hong Kong ethnic Chinese presenting within 3 years, which are confirmed with clinicopathologic features and genetic studies. The incidence is estimated to be at least 1 in 45 226 livebirths (at least 1 in 41 608 among ethnic Chinese livebirths) in Hong Kong.

Adulteration of proprietary Chinese medicines and health products with undeclared drugs: experience of a tertiary toxicology laboratory in Hong Kong.

Aims: Proprietary Chinese medicines (pCMs) and health products, generally believed to be natural and safe, are gaining popularity worldwide. However, the safety of pCMs and health products has been severely compromised by the practice of adulteration. The current study aimed to examine the problem of adulteration of pCMs and health products in Hong Kong.

Improvement of bone mineral density after enzyme replacement therapy in Chinese late-onset Pompe disease patients.

Objective: Late-onset Pompe disease (LOPD) is a lysosomal storage disease resulted from deficiency of the enzyme acid α-glucosidase. Patients usually develop a limb-girdle pattern of myopathy and respiratory impairment, and enzyme replacement therapy (ERT) is the only specific treatment available. Recently, LOPD has been associated with low bone mineral density (BMD), but the effect of ERT on BMD is inconclusive.

NMR-based urinalysis for rapid diagnosis of β-ureidopropionase deficiency in a patient with Dravet syndrome.

Background: Beta-ureidopropionase deficiency is a rare inborn error of metabolism (IEM) affecting pyrimidine metabolism. To-date, about 30 genetically confirmed cases had been reported. The clinical phenotypes of this condition are variable; some patients were asymptomatic while some may present with developmental delay or autistic features.

Electronic chemical pathology consultation service and dried blood spot metabolic screening in hospital patients.

Aim: Inborn errors of metabolism (IEM) are an unpopular and difficult subject and most clinicians are unfamiliar with them. Although chemical pathologists have a long-standing practice in advising test strategy and result interpretation especially from primary care, such consultations are usually informal, unstructured and those related to IEM are infrequently requested. This study aims to provide a formal electronic consultation service and to apply tandem mass spectrometry-based dried blood spot metabolic screening (DBSM) as a rapid first-line test for patients suspected of IEM.

Aconite poisoning over 5 years: a case series in Hong Kong and lessons towards herbal safety.

Background: Aconite poisoning is a severe, life-threatening poisoning related to the use of traditional Chinese medicine (TCM). Despite current legislation, repeated poisoning cases are steadily encountered.

Objective: The aim of the study was to summarize the clinical features and to elucidate the causative and contributory factors leading to aconite poisoning.

Phenylketonuria in Hong Kong Chinese: a call for hyperphenylalaninemia newborn screening in the Special Administrative Region, China.

Hyperphenylalaninemia is one of the commonest inborn errors of metabolism affecting approximately 1 in 15,000 livebirths. Among Chinese, BH4 deficiency leading to hyperphenylalaninemia is much commoner than in Caucasians. Exact diagnosis is important for the treatment and genetic counseling.

Analysis of inborn errors of metabolism: disease spectrum for expanded newborn screening in Hong Kong.

Background: Data of classical inborn errors of metabolism (IEM) of amino acids, organic acids and fatty acid oxidation are largely lacking in Hong Kong, where mass spectrometry-based expanded newborn screening for IEM has not been initiated. The current study aimed to evaluate the approximate incidence, spectrum and other characteristics of classical IEM in Hong Kong, which would be important in developing an expanded newborn screening program for the local area.

Methods: The laboratory records of plasma amino acids, plasma acylcarnitines and urine organic acids analyses from year 2005 to 2009 inclusive in three regional chemical pathology laboratories providing biochemical and genetic diagnostic services for IEM were retrospectively reviewed.