MYOSITIS
Although myalgias occur commonly in SLE, true myositis is relatively rare. On study of SLE patients in NIH found a prevalence of myositis of 8 %28 In most of these patients, myositis usually involves proximal upper and lower extremities. Histologic findings in SLE myositis are often less pronounced than those observed in polymyositis.
RENAL INVOLVEMENT
Renal involvement in SLE can be in the form of
1) Immune complex glomerulonephritis ( most common)
2) Tubulointerstitial disease
3) Vascular disease.
Tubulointerstitial disease has been observes in upto 66% of SLE renal biopsy specimens. and is characterised by inflammatory cell infiltrates, tubular damage and interstitial fibrosis. The presence of tubulointerstitial disease …show more content…
Class III Focal Lupus Nephritis
Active or inactive, focal ,segmental, or global endocapillary or extracapillary glomerulonephritis involving less than 50 % of all glomeruli,typically with focal subendothelial immune deposits,with or without mesangial alterations.
Class IV Diffuse Lupus Nephritis
Active or inactive diffuse, segmental or global endocapillary or extracapillary glomerulonephritis involving greater than 50 % of all glomeruli typically with diffuse subendothelial immune deposits, with or without mesangial alterations. This class is divided into diffuse segmental lupus nephritis, when less than 50 percent of the involved glomeruli have segmental lesions, and diffuse global glomerulonephritis when greater than 50 % of the involved glomeruli will have global lesions. Segmental is defined as a glomerular lesion involving less than half of the glomerular tuft.
Class V Membranous Lupus Nephritis
Global or segmental subepithelial immune deposits, or their morphologic sequelae by light microscopy and by immunofluorescence or electron microscopy, with or without mesangial alterations
Class V may occur with class 3 or class 4 in which case both are …show more content…
But the spot ratio is not standard as the ratio is not representative of the findings in a timed collection. .Many experts therefore currently recommend calculation of the 24 hour urine protein-creatinine ratio for proteinuria assessment.
KIDNEY BIOPSY
When a patient with SLE has laboratory or clinical features that suggest the presence of nephritis, a renal biopsy should be performed to confirm the diagnosis, evaluate the degree of disease activity and determine an appropriate course of treatment. Immunofluorescence studies are an important supplement to the findings on light microscopy Immunofluorescence reveals the type and pattern of immune complex deposition. Lupus nephritis is characterised by a granular pattern of immunofluorescence along the glomerular basement membrane , mesangium, and/or tubular basement membranes. The characteristic findings of lupus nephritis are sometimes referred to as the “full house” pattern, because, IgM,IgG, IgA, C3, C1q are all found in the deposits. Electron microscopy is useful in more precisely localizing the sites of immune complex deposition. The finding of tubuloreticular inclusion bodies is strongly suggestive of the diagnosis of lupus
Although myalgias occur commonly in SLE, true myositis is relatively rare. On study of SLE patients in NIH found a prevalence of myositis of 8 %28 In most of these patients, myositis usually involves proximal upper and lower extremities. Histologic findings in SLE myositis are often less pronounced than those observed in polymyositis.
RENAL INVOLVEMENT
Renal involvement in SLE can be in the form of
1) Immune complex glomerulonephritis ( most common)
2) Tubulointerstitial disease
3) Vascular disease.
Tubulointerstitial disease has been observes in upto 66% of SLE renal biopsy specimens. and is characterised by inflammatory cell infiltrates, tubular damage and interstitial fibrosis. The presence of tubulointerstitial disease …show more content…
Class III Focal Lupus Nephritis
Active or inactive, focal ,segmental, or global endocapillary or extracapillary glomerulonephritis involving less than 50 % of all glomeruli,typically with focal subendothelial immune deposits,with or without mesangial alterations.
Class IV Diffuse Lupus Nephritis
Active or inactive diffuse, segmental or global endocapillary or extracapillary glomerulonephritis involving greater than 50 % of all glomeruli typically with diffuse subendothelial immune deposits, with or without mesangial alterations. This class is divided into diffuse segmental lupus nephritis, when less than 50 percent of the involved glomeruli have segmental lesions, and diffuse global glomerulonephritis when greater than 50 % of the involved glomeruli will have global lesions. Segmental is defined as a glomerular lesion involving less than half of the glomerular tuft.
Class V Membranous Lupus Nephritis
Global or segmental subepithelial immune deposits, or their morphologic sequelae by light microscopy and by immunofluorescence or electron microscopy, with or without mesangial alterations
Class V may occur with class 3 or class 4 in which case both are …show more content…
But the spot ratio is not standard as the ratio is not representative of the findings in a timed collection. .Many experts therefore currently recommend calculation of the 24 hour urine protein-creatinine ratio for proteinuria assessment.
KIDNEY BIOPSY
When a patient with SLE has laboratory or clinical features that suggest the presence of nephritis, a renal biopsy should be performed to confirm the diagnosis, evaluate the degree of disease activity and determine an appropriate course of treatment. Immunofluorescence studies are an important supplement to the findings on light microscopy Immunofluorescence reveals the type and pattern of immune complex deposition. Lupus nephritis is characterised by a granular pattern of immunofluorescence along the glomerular basement membrane , mesangium, and/or tubular basement membranes. The characteristic findings of lupus nephritis are sometimes referred to as the “full house” pattern, because, IgM,IgG, IgA, C3, C1q are all found in the deposits. Electron microscopy is useful in more precisely localizing the sites of immune complex deposition. The finding of tubuloreticular inclusion bodies is strongly suggestive of the diagnosis of lupus