A 31 year old Chinese man developed the nephrotic syndrome, and wasfound to have some of the clinical features of renal vein thrombosis such as a rapid deterioration in renal function and great variability in proteinuria. Radiological studies confirmed the diagnosis of bilateral renal vein thrombosis. The clinical features and pathogenesis of renal vein thrombosis are discussed.
A 31-year-old Malay female presented with nephrotic syndrome without renal impairment. Renal biopsy features were in keeping with immunotactoid glomerulopathy (ITG). Non-Congophilic deposits were seen causing thickening of the glomerular capillary basement membrane with segmental accentuation, and widening of the mesangium. Immunofluorescence examination showed moderate amounts of IgG and C3 in the glomerular capillary walls with some in the mesangium. Ultrastructurally, 20-nm thick fibrils with microtubular organisation were present predominantly in the subendothelial region with similar fibrils in the mesangium. Although immunotactoid glomerulopathy and fibrillary glomerulonephritis (FG) have been recognised as entities with extracellular fibrillary material in the kidney, to date much remains to be clarified regarding these 2 conditions. While the renal biopsy findings in this patient are consistent with ITG, her clinical presentation is unlike that of usual ITG in that she is of a much younger age and has no associated haemopoietic disorder. Response to initial treatment of 8 weeks of prednisolone therapy was poor.
Adequately biopsied renal tissue received in the Department of Pathology, University Hospital, Kuala Lumpur from 1,000 consecutive Malaysian patients during an eleven year period between 1970 and 1981 was reviewed. The youngest patient was 6 days old and the oldest 80 years. Both sexes were equally represented. The majority of the patients were Chinese (71%) with Malays and Indians comprising most of the remainder. Over half the patients (50.4%) presented with the nephrotic syndrome. Other modes of presentation included systemic lupus erythematosus, proteinuria and haematuria separately or in combination and hypertension. Minimal change (25.7%) and proliferative glomerulonephritis (24.8%) were present in about equal numbers and together accounted for over half of the cases (50.5%). Lupus nephritis was the third most common diagnosis (18.4%). In addition, there were patients with focal glomerulonephritis (5.4%), membranous glomerulonephritis (5.5%), Berger's disease (5.8%), amyloidosis (0.6%) and end stage renal disease (4.0%).
Galloway-Mowat syndrome (GAMOS) is an autosomal-recessive disease characterized by the combination of early-onset nephrotic syndrome (SRNS) and microcephaly with brain anomalies. Here we identified recessive mutations in OSGEP, TP53RK, TPRKB, and LAGE3, genes encoding the four subunits of the KEOPS complex, in 37 individuals from 32 families with GAMOS. CRISPR-Cas9 knockout in zebrafish and mice recapitulated the human phenotype of primary microcephaly and resulted in early lethality. Knockdown of OSGEP, TP53RK, or TPRKB inhibited cell proliferation, which human mutations did not rescue. Furthermore, knockdown of these genes impaired protein translation, caused endoplasmic reticulum stress, activated DNA-damage-response signaling, and ultimately induced apoptosis. Knockdown of OSGEP or TP53RK induced defects in the actin cytoskeleton and decreased the migration rate of human podocytes, an established intermediate phenotype of SRNS. We thus identified four new monogenic causes of GAMOS, describe a link between KEOPS function and human disease, and delineate potential pathogenic mechanisms.