MRO's: Specimen Validity Testing

[salutations]

When it comes to urine specimen validity testing, SAMHSA* is clear about the dilute, substituted, and invalid criteria for creatinine (Cr) and specific gravity (SG) but fails to provide guidance regarding other potential, interesting results. I am therefore curious, what is the MRO's interpretation of:

1. low Cr (>= 2 but < 20 mg/dL) AND normal SG (>= 1.0030)?
2. low SG (> 1.0010 but < 1.0030) AND normal Cr (>= 20 mg/dL)?
3. high Cr† (> 200 mg/dL) AND normal SG?
4. high SG† (> 1.0200) AND normal Cr?
5. both high Cr AND high SG?

* http://beta.samhsa.gov/sites/default/files/mro-manual.pdf:

  Reporting Criteria  | Creatinine  &&  Specific Gravity
===========================================================
(IITF) Neg. - Dilute  |  >5, <20    &&  >1.0010, <1.0030
-----------------------------------------------------------
  Pos./Neg. - Dilute  | >=2, <20    &&  >1.0010, <1.0030
===========================================================
     Substituted      |    <2       &&  <1.0010 OR >=1.0200
===========================================================
       Invalid        |    <2       &&  >1.0010, <1.0200
-----------------------------------------------------------
       Invalid        |   >=2       &&  <= 1.0010
===========================================================
Adulterated: Endogenous substance not of normal physiolo-
             gical conc. (>= Limit of Quantification)

† outside of SG > 1.0200 (with concurrent Cr < 2 mg/dL) as part of the substituted criteria:

1. are there even upper limits defined for Cr or SG? If so, what are they really?
2. What is the limit of quantification for Cr or SG?

Thank you for reading my post. Also, please let me know if this even in the correct section; I sort of assumed that MRO's are required to be Pathologists.

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