Hill et al developed an index for evaluating renal biopsies from a patient with lupus nephritis. One component is the tubulointerstitial activity index (TIAI). The authors are from Hopitaux Broussais, St. Louis, Henri Mondor and Bichat in Paris.
Patient selection: lupus nephritis
Specimen: renal biopsy
Parameters:
(1) tubular cell pyknosis (tubpyk)
(2) tubular nuclear activation (tubact)
(3) tubular cell necrosis (tubnec)
(4) tubular cell flattening (tubflat)
(5) macrophages in tubular lumens (macrlum)
(6) epithelial cells in tubular lumens (eplum)
(7) interstitial inflammation (intinfl)
|
Change
|
Score
|
|
none
|
0
|
|
mild
|
1
|
|
moderate
|
2
|
|
severe
|
3
|
where:
• All histologic changes are scored equally.
total tubulointerstitial activity index =
= SUM(points for all 7 parameters)
Interpretation:
• minimum score: 0
• maximum score: 21
• The higher the score the greater the tubulointerstitial activity.
Performance:
• The relationship with activity of lupus nephritis requires exclusion of other cause of tubulointerstitial change such as medications.
