BACKGROUND: Dent disease type I is a rare X-linked recessive renal tubular disease resulting from pathogenic variants in the CLCN5 gene. Due to the rarity of Dent disease type I and the diversity of its phenotypes, its clinical diagnosis is complex and poses a challenge to clinicians.
METHODS: A foetus and a child from a 36-year-old pregnant woman with a birth history of abnormal children were enrolled in this study. Pregnant women undergo amniocentesis for prenatal diagnosis at the gestational age of 12+ 3 weeks. Chromosomal microarray (CMA) analysis and whole-exome sequencing (WES) were employed to investigate the chromosomal copy number and single gene variants. Literature retrieval and data analysis were performed for genotype and phenotype collection analysis.
RESULTS: No chromosomal abnormalities or CNVs were detected in the entire family through karyotype and familial CMA analyses. WES identified a nonsense pathogenic variant in CLCN5 of the X chromosome, c.1942 C > T (exon 11, NM_000084), which was inherited from his mother, who exhibited regular clinical features.
CONCLUSIONS: This study suggests that children with low-molecular-weight proteinuria and hypercalciuria should undergo prompt genetic testing to exclude Dent disease.

Dent\'s disease is an X-linked inherited renal tubular disorder characterized by proteinuria, hypercalciuria, nephrocalcinosis, nephrolithiasis, rickets, and end-stage renal disease. Almost 60% of patients have causative mutations in the CLCN5 gene (Dent 1), and 15% of affected individuals have mutations in the OCRL1 gene (Dent 2). The aims of this study are to identify CLCN5 mutations in Iranian families with Dent\'s disease and to characterize the associated clinical syndromes.
We studied 14 patients from 13 unrelated Iranian families with a clinical diagnosis of Dent\'s disease. Proteinuria was detected in all patients. Nephrolithiasis was found in 5 patient, and hematuria in 2 patients. Most of the affected individuals had nephrocalcinosis. PCR-sequencing for the CLCN5 gene was performed in all 14 patients. Next-generation sequencing (NGS) has also been performed in one patient who we did not find causative mutation.
We identified four different CLCN5 mutations including one missense mutation (c.731C>T), one nonsense mutation (c.100C>T), and two novel mutations, consisting of one frameshift mutation (c.1241_1242dupAA) and one splicing mutation (c.805-2A>G). We also identified one OCRL1 mutation, one splicing mutation (c.1466 + 1G>A), using NGS.
This is the first report to characterize mutations in the CLCN5 gene in Iranian patients with Dent\'s disease and expands the spectrum of CLCN5 mutations by reporting two novel mutations, c.1241_1242dupAA and c.805-2A>G.

Dent disease is a rare X-linked recessive inherited tubular disease. In this multicenter study, the clinical presentation and genetic background of Chinese children with Dent disease are studied to improve the cognition and diagnostic ability of pediatricians. In this prospective cohort, we described the genotype and phenotype of a national cohort composed of 45 pediatric probands with Dent disease belonging to 45 families from 12 different regions of China recruited from 2014 to 2018 by building up the multicenter registration system. The CLCN5 gene from 32 affected families revealed 28 different mutations. The OCRL gene from 13 affected families revealed 13 different mutations. The incidence of low-molecular-weight proteinuria (LMWP) in both Dent disease type 1 populations and Dent disease type 2 populations was 100.0%; however, the incidence of other manifestations was not high, which was similar to previously reported data. Therefore, LMWP is a key clinical feature that should alert clinicians to the possibility of Dent disease. A high amount of LMWP combined with positive gene test results can be used as the diagnostic criteria for this disease. The diagnostic criteria are helpful in reducing the missed diagnosis of this disease and are beneficial for protecting the renal function of these patients through early diagnosis and early intervention.

Combination analgesia is often recommended for the relief of severe pain. This was a double-blind, 5-arm, parallel-group, placebo-controlled, randomised, single-dose study designed to compare the efficacy and tolerability of a novel single-tablet combination of ibuprofen and paracetamol with that of an ibuprofen/codeine combination, and a paracetamol/codeine combination, using the dental impaction pain model. Subjects with at least 3 impacted third molars and experiencing moderate to severe postoperative pain were randomised to receive: 1 or 2 tablets of a single-tablet combination of ibuprofen 200mg/paracetamol 500mg; 2 tablets of ibuprofen 200 mg/codeine 12.8mg; 2 tablets of paracetamol 500mg/codeine 15mg; or placebo. Results for the primary endpoint, the sum of the mean scores of pain relief combined with pain intensity differences over 12hours, demonstrated that 1 and 2 tablets of the single-tablet combination of ibuprofen/paracetamol were statistically significantly more efficacious than 2 tablets of placebo (P<0.0001) and paracetamol/codeine (P⩽0.0001); furthermore, 2 tablets offered significantly superior pain relief to ibuprofen/codeine (P=0.0001), and 1 tablet was found noninferior to this combination. Adverse events were uncommon during this study and treatment emergent adverse events were statistically significantly less frequent in the groups taking the ibuprofen/paracetamol combination compared with codeine combinations. In conclusion, 1 or 2 tablets of a single-tablet combination of ibuprofen 200mg/paracetamol 500mg provided highly effective analgesia that was comparable with, or superior to, other combination analgesics currently indicated for strong pain. A single-tablet combination of ibuprofen 200mg/paracetamol 500mg provides highly effective analgesia, comparable or superior to other combination analgesics indicated for strong pain.