The "point of no return" and the rate of progression in the natural history of IgA nephritis.
BACKGROUND
Based on the observation of 7 patients with chronic IgA nephritis and on a course to end-stage renal failure after several years, D'Amico et al. [1993] reported on a "point of no return" at 2.5 to 3 mg/dl serum creatinine. After exceeding this limit all 7 patients exhibited an irreversible progressive renal failure.


METHODS
Therefore, 115 patients with IgA nephritis from the "German Glomerulonephritis Therapy Study" were examined in order to look for the existence of such a "point of no return".


RESULTS
Three different courses could be distinguished: a stable chronic course with constantly normal or only minor elevated serum creatinine lasting for years (91 patients), a progressive course with continuously increasing serum creatinine (22 patients), and a rare (only 2 patients) early acute course with a short-term increase of serum creatinine followed by a rapid return to the normal range. After exceeding 3 mg/dl serum creatinine no remissions were observed in the progressive cases. Sixteen patients showed a rapid, continuously progressive course until end-stage renal failure with exactly the same progression as the 7 patients of D'Amico et al. Six patients of the 22 progressors were not observed long enough. The serum creatinine level doubled on average from 3 to 6 mg/dl within 10 months.


CONCLUSIONS
Our study confirmed the existence of a "point of no return" at 3 mg/dl (265 micromol/l) during the natural course of chronic IgA nephritis.
Schöll
U
U
Nephrology, Medical Department, Hospital, University Ulm, Germany.
Wastl
U
U
Risler
T
T
Braun
N
N
Grabensee
B
B
Heering
P
P
Schollmeyer
P
P
Zäuner
I
I
Stein
G
G
Fünfstück
R
R
Keller
F
F
D000293:Adolescent; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D003404:Creatinine / Q000097:blood*; D018450:Disease Progression; D005260:Female; D005922:Glomerulonephritis, IGA / Q000097:blood* / Q000150:complications; D006801:Humans; D007676:Kidney Failure, Chronic / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis
D003404:Creatinine