Early indicators of renal dysfunction in silicotic workers

Scand J Work Environ Health. 1994 Jun;20(3):180-3. doi: 10.5271/sjweh.1411.


Objectives: The aim of this study was to determine whether silicosis is associated with renal alterations detectable in urinary or blood-borne indicators of nephrotoxicity.

Methods: The study used a cross-sectional design. The subjects comprised 116 male workers who had been exposed to silica for at least two years and had been diagnosed as having silicosis and 61 age-matched referents. The considered outcome measures were the concentrations of beta, -microglobulin and creatine in serum and the urinary excretion of albumin, retinol-binding protein, and beta-N-acetyl-D-glucosaminidase.

Results: Compared with the referents, the silicotic subjects excreted, on the average, slightly higher amounts of albumin, retinol-binding protein, and beta-N-acetyl-D-glucosaminidase. This increase did not correlate with the duration of exposure or the stage of silicosis and was not associated with an elevation in serum creatinine. The concentration of beta2-microglobulin in the serum of silicotic subjects showed a tendency to rise that became significant in the subgroup with pseudotumoral opacities. This effect, which did not correlate with markers of nephrotoxicity, is however more likely the consequence of silicosis-associated inflammatory reactions than of decreased renal filtration.

Conclusions: The present study confirms that silicosis is associated with some infraclinical renal alterations. However, in the absence of a relationship with length of exposure or severity of silicosis, the implication of silica in their causation needs to be examined further.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylglucosaminidase / blood
  • Acetylglucosaminidase / urine
  • Adult
  • Aged
  • Aged, 80 and over
  • Albuminuria
  • Case-Control Studies
  • Causality
  • Creatinine / blood
  • Creatinine / urine
  • Cross-Sectional Studies
  • Humans
  • Kidney Diseases / complications
  • Kidney Diseases / diagnosis*
  • Kidney Diseases / urine
  • Male
  • Middle Aged
  • Retinol-Binding Proteins / urine
  • Severity of Illness Index
  • Silicosis / complications*
  • Silicosis / urine
  • Time Factors
  • beta 2-Microglobulin / urine


  • Retinol-Binding Proteins
  • beta 2-Microglobulin
  • Creatinine
  • Acetylglucosaminidase