Non-diabetic glycosuria as a diagnostic clue for acute tubulointerstitial nephritis in patients with azotemia.
BACKGROUND
Glycosuria is one of the manifestations of acute tubulointerstitial nephritis (ATIN), but may also be observed in other renal diseases. In this study, we investigated the value of non-diabetic glycosuria as a diagnostic clue for ATIN.


METHODS
We retrospectively reviewed the medical records of adult patients who underwent a kidney biopsy as an evaluation for serum creatinine > 1.4 mg/dL. Patients with proteinuria in the nephrotic range, diabetes mellitus, or transplanted kidney were excluded. The laboratory abnormalities suggestive of tubular injury were compared between 28 patients (14 men and 14 women, mean age 48.5 ± 14.1 years) with ATIN and 116 patients (76 men and 40 women, mean age 53.1 ± 15.0 years) with other diagnoses.


RESULTS
In ATIN, glycosuria (≥ 1+ on dipstick; 68%) was more frequent than hypophosphatemia (18%), hypouricemia (18%), hypokalemia (18%), and tubular proteinuria (40%). In other diagnoses, glycosuria (≥ 1+) was detected in 7 (6%) patients; 6 of them had the histological diagnosis of antineutrophil cytoplasmic antibody-associated glomerulonephritis. The presence of glycosuria (≥ 1+) had 68% sensitivity and 94% specificity for ATIN, with the positive likelihood ratio of 11.24 and the negative likelihood ratio of 0.34. Pyuria and low total CO2 were equally and more sensitive (68% and 71%, respectively) than glycosuria (≥ 1+), but had no diagnostic value due to low specificities (58% and 60%, respectively).


CONCLUSION
In non-diabetic, non-nephrotic patients undergoing a kidney biopsy for azotemia, 1+ or higher glycosuria, if present, was a good predictor of the diagnosis of ATIN.
['Lee|Taeyeon|T|', 'Yang|Won Seok|WS|']
D000328:Adult D000368:Aged D053099:Azotemia D001706:Biopsy D003404:Creatinine D005260:Female D006029:Glycosuria D006801:Humans D007008:Hypokalemia D007668:Kidney D008297:Male D008875:Middle Aged D009395:Nephritis, Interstitial D011507:Proteinuria D012189:Retrospective Studies D012680:Sensitivity and Specificity
glycosuria Acute tubulointerstitial nephritis hypophosphatemia hypouricemia hypokalemia anti-neutrophil cytoplasmic antibody