Page 125 - Concise Pathology for Exam Preparation ( PDFDrive )

110 SECTION I General Pathology

TABLE 5.11. Year 1997 revised criteria for the classification of SLE

1. Malar rash Fixed erythema, flat or raised over the malar eminences
2. Discoid rash Erythematous raised patches with adherent keratotic scaling and follicular plugging
3. Photosensitivity Skin rash due to exposure to UV light
4. Oral ulcers Oral or nasopharyngeal ulceration
5. � Arthritis Nonerosive arthritis involving two or more peripheral joints causing tenderness,
swelling and effusion
6. � Serositis Pleuritis (history of pleuritic pain or rub or effusion), pericarditis (ECG documen-
tation or pericardial rub or effusion)
7. � Renal disorder Persistent proteinuria (.0.5g/dl) and cellular casts (RBC, haemoglobin, granular,
tubular or mixed)
8. Neurological disorder Seizures and psychosis (unexplained)
9
9. � Haematological disorder Haemolytic anaemia with reticulocytosis, leucopenia (,4x10 cells/L), lymphope-
9
nia (,1.5x10 cells/L) and thrombocytopenia (,100x10 9 cells/L)
10. � Immunologic disorder Anti-ds DNA, anti-Sm antibody; positive findings of antiphospholipid syndrome
(increased IgM or IgG anticardiolipin antibodies, positive test for lupus antico-
agulant, false positive serologic test for syphilis confirmed by negative TPI or
FTABS)
11. � Antinuclear antibodies Positive antinuclear antibodies (in the absence of drugs known to be associated
with drug-induced SLE)

Kidneys
• �Light microscopic involvement is seen in 60–70% cases; whereas, immunofluorescence
(IF) and electron microscopic (EM) changes are seen in most cases.
• �Five morphological patterns are recognized based on WHO morphologic criteria:

1. Class I: Rare; no changes seen on light microscopy; however, IF or EM can identify
immune complex deposition in the mesangium.

2. Class II: Also called mesangial lupus glomerulonephritis, this comprises 20% of all
cases and manifests with minimal clinical symptoms. It is morphologically character-
ized by:
(a) Increased intercapillary mesangial matrix and cells

(b) Granular mesangial deposits of immunoglobulins and complement on IF

3. Class III: Also called focal proliferative glomerulonephritis, this manifests with mild
to moderate haematuria and proteinuria. It is morphologically characterized by:

(a) Involvement of less than 50% of all glomeruli.
(b) Swelling and proliferation of endothelial and mesangial cells.

(c) Neutrophilic infiltrate; fibrinoid deposits, and intercapillary thrombi. Extracapil-

lary proliferation with crescent formation may also be seen.
4. Class IV: Also called diffuse proliferative glomerulonephritis, this is overtly symp-

tomatic and shows the following morphological features:

(a) More than 50% glomeruli are affected.

(b) Involvement of the entire glomerulus is labelled ‘global’ (IV-G) glomerulonephri-
tis and part of the glomerulus is labelled ‘segmental’ (IV-S) glomerulonephritis

(c) There is proliferation of endothelial, mesangial and epithelial cells.

(d) Epithelial crescents may be seen in Bowman’s space.

(e) Also present are fibrinoid necrosis and hyaline thrombi in glomeruli.
5. Class V: Also called membranous glomerulonephritis. It comprises 15% of all cases

and manifests with severe proteinuria with nephrotic syndrome. Main light micro-
scopic change is widespread thickening of capillary walls.
6. Class VI: Advanced sclerosing lupus nephritis represents end-stage renal disease

wherein .90% glomeruli are sclerosed.
• �The immune complexes may be deposited in the basement membrane, mesangium,
subepithelial zone (between basement membrane and visceral epithelial cells, as in
membranous glomerulonephritis) and subendothelial zone (between basement mem-
brane and endothelium). When extensive, subendothelial deposits create a peculiar
thickening of the capillary wall called ‘wire loop lesions’.
mebooksfree.com