#4044 FOCAL SEGMENTAL GLOMERULOSCLEROSIS DUE TO A3243G POINT MUTATION IN THE MTDNA CODING FOR TRNALEU(UUR)

Abstract Background and Aims Mitochondrial Diseases represent a heterogeneous set of maternally inherited diseases that arise by mutations either the mitochondrial DNA (mtDNA) or in genes nuclear (nDNA) linked to cell cross-talk. Many mtDNA code for different are wide spectrum kidney manifestations ranging from focal segmental glomerulosclerosis (FSGS), tubule-interstitial disease (TIN), nephrotic syndrome (NS), proximal distal tubulopathy. Renal disorders poorly recognized clinical practice often misdiagnosed other conditions like FSGS, Alport Syndrome, steroid-resistant syndrome. The guanine adenine point mutation (A–>G) at position 3243 has emerged as most common found patient with FSGS accompained diabetes mellitus deafness. Focal Segmental Glomerulosclerosis, (FSGS) is prevalent histologic finding patients mutations. Epidemiologic studies have shown about 1% diabetic populations Europe Japan this mutation. Method A 34-year-old man presented evaluation recently diagnosed Type II serum creatinine 3.9 mg/dL range proteinuria (3.2 gr/die). His family history included mellitus, chronic disease, coronary artery hypertension. medical hypertension, dyslipidemia, sensorineural hearing loss which had initially developed during adolescence. Serum was reportedly elevated years before presentation, urinalysis showed mild no microhematuria, white cells, casts. Results On his blood pressure 150/90 mmHg, peripheral leg edema. Laboratory results 3.4 mg/dl (eGFR 23 ml/min), HbA1c 7.2%, albumin 2.8 gr/dL. Urinalysis protein (3+), glucose (+1) hematuria. Urinary protein-creatinine ratio 3 mg/g. C3 C4, immunoglobulins, liver enzymes were normal; autoimmunity tested negative (ANCA, Anti-PLA2r, Anti antobodies). biopsy performed. Light microscopy revealed glomeruli obliteration glomerular capillaries collagenous sclerosis (Fig. 1). Both Jones methenamine silver stain Masson's trichrome 1B, C) collagen deposition capillaries. Tubular atrophy fibrosis also present. Immunofluorescence negative. diagnosis not otherwise specified (NOS FSGS) made. Interestingly electron abnormalities tubular cells. In particular, cytoplasm appears be whiffed mitochondria enlarged size altered shape 2). Mithocondria appeared dysmorphic extensive reduction cristae 2 arrows). screened substitution detected. received histological features due an A3243G associated Conclusion This case underscores role identifying mithocondrial related nephropathies. Even more important evaluate cases familial loss, cardiomyopathy diabetes.