Glomerular Proteinuria Predicts the Severity of Acute Kidney Injury in Puumala Hantavirus-Induced Tubulointerstitial Nephritis.
BACKGROUND
Puumala virus (PUUV)-induced hemorrhagic fever with renal syndrome is common in many European countries. The typical renal histologic lesion is acute tubulointerstitial nephritis. We examined the type and kinetics of urine protein excretion and prognostic significance of proteinuria for the severity of acute kidney injury (AKI) in acute PUUV infection.


METHODS
The amount of dipstick albuminuria at hospital admission was analyzed in 205 patients with acute PUUV infection. Dipstick albuminuria at admission was graded into 3 categories: 0-1+, 2+, and 3+. In 70 patients, 24-h urinary excretion of protein, overnight urinary excretion of albumin, immunoglobulin (Ig) G, and α1-microglobulin also were measured over 3 consecutive days during the hospital stay.


RESULTS
Maximum median daily proteinuria, overnight albuminuria, and IgG excretion were observed over 5 days, while that of creatinine values was observed 9 days after the onset of the disease. The medians of maximum plasma creatinine levels during hospital stay were different in the 3 categories of dipstick albuminuria: 0-1+: 98 µmol/L (58-1,499), 2+: 139 µmol/L (71-829), and 3+: 363 µmol/L (51-1,285; p < 0.001). Dipstick albuminuria ≥2+ at admission could be detected in 89% of the patients who subsequently developed severe AKI. Glomerular proteinuria, but not tubular proteinuria (α1-microglobulin), correlated with the severity of the emerging AKI.


CONCLUSIONS
In acute PUUV infection, maximum median proteinuria values preceded the most severe phase of AKI by a few days. A highly useful finding for clinical work was that a quick and simple albuminuria dipstick test at hospital admission predicted the severity of the upcoming AKI.
National Reference Centre for Hantaviruses, University Hospitals Leuven, Leuven, Belgium.
Paula S
PS
Mantula
Tuula K
TK
Outinen
Jan P G
JPG
Clement
Heini S A
HSA
Huhtala
Ilkka H
IH
Pörsti
Antti
A
Vaheri
Jukka T
JT
Mustonen
Satu M
SM
Mäkelä
D000293:Adolescent; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006480:Hemorrhagic Fever with Renal Syndrome / Q000150:complications*; D006801:Humans; D007678:Kidney Glomerulus / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009395:Nephritis, Interstitial / Q000150:complications*; D011507:Proteinuria / Q000150:complications* / Q000473:pathology; D029262:Puumala virus / Q000472:pathogenicity*; D012720:Severity of Illness Index; D055815:Young Adult
Acute kidney injury; Acute tubulointerstitial nephritis; Albuminuria; Hantavirus; Proteinuria; Puumala virus