Urea Cycle Marker Screen

Cross-check urea-cycle markers against user-selected screening cutoffs.

Description

A two-marker screen compares arginine and orotidine with supplied cutoffs.

A two-marker screen compares arginine and orotidine with supplied cutoffs. The combined flag requires both a low first marker and high second marker.^[1]

Cross-check urea-cycle markers against user-selected screening cutoffs.

When to use Urea Cycle Marker Screen

Use this tool to cross-check urea-cycle markers against user-selected screening cutoffs.

Prepare the measured profile, formula counts, upstream model outputs or caller-defined reference criteria requested. Keep paired entries aligned and units, sample basis and preprocessing consistent.

How to use Urea Cycle Marker Screen and understand its results

Prepare the measured profile, formula counts, upstream model outputs or caller-defined reference criteria requested. Keep paired entries aligned and units, sample basis and preprocessing consistent.
Enter arginine, orotidine, arginineMinimum, orotidineMaximum using the field table and calculation rules, then run the tool.
Read arginineLow, orotidineHigh, crossCheckFlag. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
arginine	Arginine	number	Required
orotidine	Orotidine	number	Required
arginineMinimum	Arginine minimum	number	Required
orotidineMaximum	Orotidine maximum	number	Required

Enter nonnegative marker concentrations and finite compatible cutoffs. Return each strict comparison and their conjunction; equality does not flag a marker.

crossCheck=(arginine<minimum) AND (orotidine>maximum)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
arginineLow	Arginine low	boolean
orotidineHigh	Orotidine high	boolean
crossCheckFlag	Cross check flag	boolean

json

{
  "input": {
    "arginine": 10,
    "orotidine": 5,
    "arginineMinimum": 8,
    "orotidineMaximum": 4
  },
  "output": {
    "arginineLow": false,
    "orotidineHigh": true,
    "crossCheckFlag": false
  }
}

Limitations and assumptions

Cutoffs are not clinical reference ranges embedded by the tool. This does not diagnose a urea-cycle condition or evaluate sample context.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use TMAO Risk Band: Classify TMAO concentration against caller-supplied research bands, not a clinical diagnosis. For a complementary task, use Porphyrin Pattern: Find excess porphyrin intermediates against caller-provided reference limits.

References

Urea Cycle Marker Screen — tool.io

Similar or alternative tools

TMAO Risk Band
Classify TMAO concentration against caller-supplied research bands, not a clinical diagnosis.
Porphyrin Pattern
Find excess porphyrin intermediates against caller-provided reference limits.