What ICD-10 codes cover the medical necessity for Porphobilinogen (PBG), Quantitative, Random Urine testing?

ICD-10 Codes for Medical Necessity of Porphobilinogen (PBG) Quantitative Random Urine Testing

The primary ICD-10 codes that justify medical necessity for PBG quantitative random urine testing are E80.0 (Hereditary erythropoietic porphyria), E80.1 (Porphyria cutanea tarda), E80.20 (Unspecified porphyria), and E80.21 (Acute intermittent (hepatic) porphyria). 1

Primary Diagnostic Codes

• E80.0 - Hereditary erythropoietic porphyria
• E80.1 - Porphyria cutanea tarda
• E80.20 - Unspecified porphyria
• E80.21 - Acute intermittent (hepatic) porphyria
• E80.29 - Other porphyria (includes hereditary coproporphyria and variegate porphyria)

Secondary Supporting Codes

• R10.0-R10.9 - Abdominal and pelvic pain (common in acute porphyria attacks)
• G62.9 - Polyneuropathy, unspecified (neurological symptoms in acute porphyrias)
• R11.0-R11.2 - Nausea and vomiting (common in acute attacks)
• K76.9 - Liver disease, unspecified (liver involvement in hepatic porphyrias)
• N18.1-N18.9 - Chronic kidney disease (complication of acute hepatic porphyrias)

Clinical Indications for Testing

PBG quantitative testing in random urine is primarily indicated for:

1. Suspected acute porphyria attacks - Characterized by:

   • Severe abdominal pain
   • Nausea and vomiting
   • Autonomic disturbance
   • Neurological symptoms

2. Monitoring known porphyria patients - For:

   • Treatment response assessment
   • Disease activity monitoring
   • Evaluation of chronic complications

Testing Considerations

• Random urine samples are sufficient and preferred over 24-hour collections 1
• Samples must be protected from light to prevent degradation 1
• Results should be normalized to creatinine for proper interpretation 1
• Urine creatinine should be >2 mmol/L for reliable interpretation 1

Diagnostic Algorithm

1. For patients with acute symptoms (abdominal pain, neurological symptoms):

   • Order random urine PBG (normalized to creatinine)
   • If PBG >10 mg/g creatinine, acute hepatic porphyria is confirmed 1
   • If normal, acute porphyria is excluded as the cause of current symptoms

2. For asymptomatic screening (family history):

   • Genetic testing is preferred after consultation with a specialist porphyria laboratory 2

Important Caveats

• PBG levels may remain elevated for months to years after an acute attack in AIP but fall quickly in HCP or VP 1
• Testing is most informative when done during symptomatic periods 1
• If only ALA is elevated (without PBG elevation), consider lead poisoning or hereditary tyrosinemia 1
• Urine total porphyrins should not be used alone as a screening test for acute hepatic porphyrias 1

By using these appropriate ICD-10 codes and following the testing guidelines, medical necessity for PBG quantitative random urine testing can be properly established for patients with suspected or confirmed porphyrias.