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Calculate urine saturation with the EQUIL-2 algorithm

equil2.Rd

Calculate urine saturation with the EQUIL-2 algorithm

Usage

equil2(
  sodium_mEq_L,
  potassium_mEq_L,
  calcium_mg_dL,
  magnesium_mg_dL,
  ammonia_mEq_L,
  chloride_mEq_L,
  phosphate_mg_dL,
  sulfate_mg_dL,
  oxalate_mg_dL,
  citrate_mg_dL,
  pH,
  urate_mg_dL
)

Arguments

sodium_mEq_L, potassium_mEq_L, ammonia_mEq_L, chloride_mEq_L

Concentration of the given species in mEq/L (or a unit value that can be converted to mEq/L)

calcium_mg_dL, magnesium_mg_dL, phosphate_mg_dL, sulfate_mg_dL, oxalate_mg_dL, citrate_mg_dL, urate_mg_dL

Concentration of the given species in mg/dL (or a unit value that can be converted to mg/dL)

pH

The urine pH

Value

A data.frame with three columns:

  • "species" indicating the chemical species

  • "super_saturation" is the supersaturation ratio. This is SS as defined in Werness 1985.

  • "neg_delta_Gibbs" which is the negative of the change in Gibbs free energy of transfer from a supersaturated to a saturated solution (the value is negative for under-saturated solutions, zero for solutions at the solubility product, and positive for supersaturated solutions). This is DG as defined in Werness 1985.

Details

This program is intended for research use, only. The code within is translated from Visual Basic code based on Werness, et al 1985 to R. The Visual Basic code was kindly provided by Dr. John Lieske of the Mayo Clinic.

References

Werness PG, Brown CM, Smith LH, Finlayson B. Equil2: A Basic Computer Program for the Calculation of Urinary Saturation. Journal of Urology. 1985;134(6):1242-1244. doi:10.1016/S0022-5347(17)47703-2

Examples

# Example values from https://files.labcorp.com/testmenu-d8/sample_reports/306266.pdf
equil2(
  sodium_mEq_L=units::set_units(45, "mmol_sodium/L"),
  potassium_mEq_L=units::set_units(55, "mmol_potassium/L"),
  calcium_mg_dL=units::set_units(15, "mg_calcium/dL"),
  magnesium_mg_dL=units::set_units(15, "mg_magnesium/dL"),
  ammonia_mEq_L=units::set_units(10, "ug_ammonia/dL"),
  chloride_mEq_L=units::set_units(75, "mmol_chloride/L"),
  phosphate_mg_dL=units::set_units(100, "mg_phosphate/dL"),
  sulfate_mg_dL=units::set_units(20, "mEq_sulfate/L"),
  oxalate_mg_dL=units::set_units(10, "mg_oxalate/L"),
  citrate_mg_dL=units::set_units(400, "mg_citrate/L"),
  pH=5.5,
  urate_mg_dL=units::set_units(50, "mg_urate/dL")
)
#>           species super_saturation neg_delta_Gibbs
#> 1 Calcium Oxalate     2.751276e+00     1.309105783
#> 2        Brushite     1.006634e+00     0.008552342
#> 3  Hydroxyapatite     1.280275e+04     2.718439456
#> 4       Uric Acid     4.524588e+00     3.905145139
#> 5    Sodium Urate     1.550834e+00     0.567578360
#> 6  Ammonium Urate     1.493353e-04   -11.394850707