Clinical and molecular characterization of Indian patients with fructose‐1, 6‐bisphosphatase deficiency: Identification of a frequent variant (E281K)

Fructose‐1, 6‐bisphosphatase deficiency is an autosomal recessive disorder of gluconeogenesis caused by genetic defect in the FBP1 gene. It is characterized by episodic, often life‐threatening metabolic acidosis, liver dysfunction, and hyperlactatemia. Without a high index of suspicion, it may remain undiagnosed with devastating consequences. Accurate diagnosis can be achieved either by enzyme assay or gene studies. Enzyme assay requires a liver biopsy and is tedious, invasive, expensive, and not easily available. Therefore, genetic testing is the most appropriate method to confirm the diagnosis. Molecular studies were performed on 18 suspected cases presenting with episodic symptoms. Seven different pathogenic variants were identified. Two common variants were noted in two subpopulations from the Indian subcontinent; p.Glu281Lys (E281K) occurred most frequently (in 10 patients) followed by p.Arg158Trp (R158W, in 4 patients). Molecular analysis confirmed the diagnosis and helped in managing these patients by providing appropriate genetic counseling. In conclusion, genetic studies identified two common variants in the Indian subcontinent, thus simplifying the diagnostic algorithm in this treatable disorder.     

Insulin-like growth factor-1 expression in reflux nephropathy

Background Reflux nephropathy (RN) is recognised as a major cause of end-stage renal failure in children and young adults. Insulin-like growth factor-1 (IGF-1), a peptide growth factor produced by collecting ducts, and its receptor, insulin-like growth factor-1 receptor (IGF-1R), are present in the glomeruli and basolateral membrane of renal proximal tubular cells. Exogenous IGF-1 has been shown to enhance proliferation and reduce apoptosis of tubular cells following renal injury.Methods We designed this study to investigate the expression of IGF-1 in RN. The kidney specimens from 15 children with RN were obtained at the time of nephrectomy. Control material included normal kidney specimens obtained from adult patients during partial nephrectomy for an incidentaloma. Single-label immunofluorescence histochemistry was carried out using polyclonal antibodies to IGF-1 and IGF-1R employing laser scanning confocal microscopy. Double-label immunofluorescence histochemistry was carried out using monoclonal antibodies to vimentin and clusterin to assess tubulointerstitial fibrosis. IGF-1 and IGF-1R gene expression were evaluated by in situ hybridisation (ISH). The TUNEL method was utilised to assess tubular apoptosis.Results In the normal kidney there was strong IGF-1 and IGF-1R immunoreactivity in the proximal tubules, whereas IGF-1 and IGF-1R immunoreactivity was markedly reduced in RN specimens. Strong IGF-1 and IGF-1R mRNA expression was observed in the proximal tubules in normal kidneys, whereas IGF-1 and IGF-1R mRNA expression was undetectable in RN. Renal tubulointerstitial expression of vimentin and clusterin was markedly increased in RN kidneys. Decreased IGF-1 and IGF-1R expression in RN strongly correlated with severity of tubular apoptosis in RN compared with controls.Conclusion These data suggest that the downregulation of IGF-1 and IGF-1R may play an important role in the pathogenesis of RN, at least in part by increasing interstitial collagen deposition and tubular apoptosis.     

Correlation of Antenatal Ultrasound Parameters with the Postnatal Outcome of Bilateral Fetal Hydronephrosis

The Journal of Obstetrics and Gynecology of India - To determine the role of antenatal parameters in predicting the outcome of bilateral fetal hydronephrosis. Total 50 antenatal women with...     

Renal parenchymal damage in sibling vesicoureteric reflux

Aim: To compare the incidence of renal damage in siblings of patients with vesicoureteric reflux (VUR) who presented with a documented history of urinary tract infection (UTI) with asymptomatic siblings who were diagnosed with reflux during a screening programme for hereditary VUR. Methods: Medical and radiological records of the VUR patients (1990-2000) were examined for age, gender, mode of presentation, reflux grade and renal damage. Results: VUR was noted in 226 siblings (352 ureters) in 107 families. Of the 119 siblings of index patients, 64 were investigated for a documented UTI and 55 with no history of UTI were detected during screening for sibling reflux. Dimercaptosuccinic acid scan revealed reflux nephropathy in 25 (26%) of the 97 renal refluxing units (RRU) of siblings who presented with a UTI and in 6 (7%) of the 89 RRU of asymptomatic siblings who underwent screening voiding cystourethrography ( p = 0.0006). Mild renal damage was present in 20 (21%) RRU of siblings with UTI and in 2 (2%) RRU of the screened siblings (p 3 0.001). Moderate to severe renal damage was present in 5 (5%) RRU of siblings with UTI and in 4 (4%) RRU of the screened siblings (p 3 0.05). Conclusion: This study demonstrated that the incidence of mild renal scarring was much higher in siblings who presented with UTI than in asymptomatic siblings. However, the incidence of moderate and severe renal scarring among asymptomatic siblings was comparable to that in siblings with VUR and UTI.     

The development of excitatory neurons in the chick cloaca

Introduction

The enteric nervous system of the chick embryo hindgut is derived from the vagal and sacral neural tube. Nerve cells from these regions produce various neuronal phenotypes, including inhibitory and excitatory nerve cells, providing intrinsic innervation to the chick embryo cloaca. We hypothesised that the vagal and sacral neural tubes provide the cloaca, with phenotypically similar nerve cells. The aim of our study was to investigate the origin of excitatory neurotransmission in the developing cloaca.

Materials and methods

Chicken embryos were incubated until the 10–12 somite stage (ss). To study the vagal neural tube contribution to the cloaca, this region was microsurgically ablated in ovo and replaced with the corresponding region from age-matched quail embryos. To study the sacral neural tube contribution to the cloaca, the vagal neural tube was ablated at the 10–12 ss, but not replaced with quail neural tube, thus, only the sacral neural crest cells remained. All embryos were harvested at E12 and E14, embedded in paraffin wax and serially sectioned. Immunohistochemistry was carried out on all embryos using human natural killer-1, quail non-chick perinuclear, choline acetyltransferase (ChAT) and substance P (SubP) antibodies.

Results

Choline acetyltransferase- and SubP-positive neurons were seen to originate in both the vagal and the sacral neural tube. The vagal neural tube provided the majority of the nerve cells to the chick embryo cloaca and expressed both ChAT and SubP in both the myenteric and submucosal plexus. The sacral neural tube contributed a lesser amount of nerve cells to the chick embryo cloaca, but was also seen to produce both ChAT- and SubP-positive nerve cells in both ganglionated plexus.

Conclusion

This study shows, for the first time, that the excitatory ChAT- and SubP-expressing neurons in the developing cloaca originate in both the vagal and the sacral neural tube. These results highlight the origin of phenotypically similar nerve cells in both regions of the neural tube, providing new insights into the developmental origin of the intrinsic innervation of the persistent cloaca.     

Systematic review and meta-analysis of enterocolitis after one-stage transanal pull-through procedure for Hirschsprung’s disease

Purpose  

The transanal one-stage pull-through procedure (TERPT) has gained worldwide popularity over open and laparoscopic-assisted one-stage techniques in children with Hirschsprung’s disease (HD). It offers the advantages of avoiding laparotomy, laparoscopy, scars, abdominal contamination, and adhesions. However, enterocolitis associated with Hirschsprung’s disease (HAEC) still remains to be a potentially life-threatening complication after pull-through operation. The reported incidence of HAEC ranges from 4.6 to 54%. This meta-analysis was designed to evaluate postoperative incidence of HAEC following TERPT procedure.