Urinalysis Urine is dark. Specific gravity is greater than 1020 osm. Proteinuria is observed. Haematuria – RBCs and red cell casts are present on microscopy – (Perform FBE to check for anaemia) Leukocytes Creatinine level increased
Asymptomatic urinary abnormalities Isolated proteinuria without haemturia – May be early sign of glomerular lesion- i.e. membranous GN, IgA nephropathy, diabetic nephropathy or amyloidosis Haematuria with/without sub-nephrotic range proteinuria – SLE, Henoch-Schonlein purpura, post-infectious GN
Blood FBE ESR, CRP for inflammation U + E’s LFT’s Serum albumin (low in nephrotic syndrome) Glucose- to exclude diabetes Serum complement (low in SLE) Auto-antibodies: serum immunoglobulins, ANCA (Wegener’s granulomatosus, anti-ss-DNA (SLE)
Imaging Chest radiography – needed in patients with a cough, with or without haemoptysis (ie, Wegener granulomatosis, Goodpasture syndrome, pulmonary congestion). Abdominal CT is needed if visceral abscesses are suspected; also look for chest abscesses. Echo For pts with new cardiac murmur or a positive blood culture rules out endocarditis or a pericardial effusion. Renal US: – to evaluate kidney size as well as to determine the extent of fibrosis. – A kidney size of less than 9 cm is suggestive of extensive scarring and a low likelihood of reversibility CT scan of the head for patient with malignant hypertension or altered mental status.
Biopsy Candidates for biopsy: – individual or family history of renal disease, atypical presentation: – massive proteinuria – nephrotic syndrome – rapid rise in creatinine level without resolution.
Post-strep GN – Biopsy shows diffuse, florid, acute inflamm at the glomerulus – No necrosis, but occaisonal crescents – Neutrophils and deposition of IgG and complement – Light microscopy of biopsy sample shows acute inflammation of glomerulus with neutrophils
IgA nephropathy (commonest form of GN) – Elevated IgA complex in mesangium – Biopsy shows mesangial cell proliferation and increased matrix
Wegener’s granulomatosus – C- ANCA that reacts with proteinase 3