Summary & Overview
CPT 0105U: KidneyIntelX™ Risk Score for Rapid Kidney Function Decline
Headline: New CPT code 0105U identifies KidneyIntelX™, an algorithm-based biomarker test that predicts rapid decline in kidney function.
CPT code 0105U designates a Proprietary Laboratory Analyses (PLA) test — KidneyIntelX™ from RenalytixAI — that integrates immunoassay measurements of tumor necrosis factors and kidney injury molecule–1 with clinical data to generate a risk score for rapid kidney function decline. Nationally, PLA codes like 0105U matter because they identify single-manufacturer, lab-specific diagnostics that can affect coverage, utilization tracking, and clinician adoption of precision diagnostics.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical intent and operational context for 0105U, plus discussion of payer coverage patterns, billing and service-line considerations, and benchmarking context where available. The publication summarizes how the test is reported, its typical laboratory site of service, and the clinical scenario it targets — risk stratification for patients at risk of rapid kidney decline.
The report does not provide clinical recommendations. It delivers actionable reference material for billing, coding, and policy teams: what 0105U represents, which major payers are relevant, and which topics (coverage variability, reimbursement framework for PLA codes, and clinical context) readers should review when evaluating adoption or contract terms.
Billing Code Overview
CPT code 0105U is a Proprietary Laboratory Analyses (PLA) code for the KidneyIntelX™ test from RenalytixAI. The test combines an immunoassay procedure that detects tumor necrosis factors and kidney injury molecule–1 with clinical data fed into an algorithm to produce a score that predicts the probability of rapid decline in kidney function in a patient.
Service Type: Proprietary laboratory diagnostic algorithm combining biomarker immunoassay and clinical data
Typical Site of Service: Clinical laboratory or reference laboratory processing with results reported to ordering clinician
Clinical & Coding Specifications
Clinical Context
A 64-year-old patient with type 2 diabetes mellitus and stage 3 chronic kidney disease is seen in nephrology clinic for progressive albuminuria and declining estimated glomerular filtration rate (eGFR). The clinician orders the KidneyIntelX™ test (0105U) to integrate plasma biomarkers (including tumor necrosis factor receptors and kidney injury molecule-1) with clinical variables and generate a validated risk score for rapid kidney function decline. Blood is drawn in clinic or at an outpatient laboratory, labeled per laboratory instructions, and shipped to the proprietary lab that performs the KidneyIntelX™ assay. Results are returned to the ordering nephrologist and incorporated into the patient’s care plan to guide monitoring frequency, medication adjustments, and referral decisions. Typical site of service is an outpatient clinic or independent clinical laboratory performing the proprietary analysis. The service is laboratory-based and supplies an algorithm-derived report rather than a procedure performed in an inpatient operative setting.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | No modifier information | Used when no specific modifier applies or payer does not require a modifier |
11 | Office/Outpatient | Use when service is provided in an office or outpatient clinic setting |
26 | Professional component | Use when reporting only the professional component if separated by the performing laboratory and ordering clinician |
52 | Reduced services | Use if test was partially completed or limited for clinical reasons |
53 | Discontinued procedure | Use if specimen collection or processing was attempted but discontinued for documented medical reasons |
55 | Postoperative services only | Rare for lab; use only if reporting relates to post-op management distinct from global care |
62 | Two surgeons | Not typical for lab test; apply only if two practitioners share responsibility for related procedural care |
78 | Return to operating room for a related procedure during the postoperative period | Not typical; include only if clinically applicable to a related surgical event |
80 | Assistant surgeon | Not typical for lab testing; apply only if an assistant surgeon is billable for a related operative service |
AD | Medical team - physician supervisor | Use when a physician supervises a medical team responsible for specimen collection or coordination |
QK | Medical direction of two or more qualified health professionals | Use when the physician provides medical direction for multiple nonphysician staff performing related services |
QX | CRNA service: medically directed by anesthesiologist | Not typically applicable to this lab test; exclude unless related anesthesia services are billed |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
2080P0208X | Nephrology | Ordering specialists who commonly use KidneyIntelX™ to risk-stratify CKD patients |
207Q00000X | Clinical Pathology | Laboratory directors and pathologists overseeing biomarker immunoassays and reporting |
207L00000X | Clinical Laboratory | Clinical laboratory personnel responsible for specimen processing and testing |
207LP2900X | Molecular Pathology | Specialty overseeing algorithmic molecular or biomarker-based analyses |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
E11.22 | Type 2 diabetes mellitus with diabetic chronic kidney disease | Diabetes is the most common cause of progressive CKD; KidneyIntelX™ risk stratification is used in this population |
N18.3 | Chronic kidney disease, stage 3 (moderate) | Intermediate-stage CKD where prediction of rapid decline informs monitoring and interventions |
N18.4 | Chronic kidney disease, stage 4 (severe) | Advanced CKD where risk scoring may influence referral timing and therapeutic decisions |
N18.9 | Chronic kidney disease, unspecified | Used when stage is not documented; test may still be ordered to clarify risk |
R80.9 | Proteinuria, unspecified | Presence of proteinuria/albuminuria is a major driver for prognostic algorithms like KidneyIntelX™ |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
81003 | Urinalysis, by dipstick or tablet reagent for bilirubin, glucose, hemoglobin, ketones, leukocytes, nitrite, pH, specific gravity, etc., non-automated, with microscopy if performed | Often ordered alongside 0105U to assess urine abnormalities and albuminuria status as part of kidney evaluation |
82043 | Microalbumin; urine | Used to quantify albuminuria, a key clinical variable considered when evaluating CKD risk and interpreting KidneyIntelX™ results |
82565 | Creatinine; serum, plasma or blood, quantitative | Serum creatinine and derived eGFR are essential clinical inputs for interpretation of the KidneyIntelX™ algorithm |
36415 | Collection of venous blood by venipuncture | Commonly billed for the blood draw required to obtain specimens for the KidneyIntelX™ assay when billed separately |
99000 | Handling and/or conveyance of specimen for transfer from the physician's office to a laboratory | Used when specimen transport or handling services are billed for sending samples to the proprietary testing laboratory |