Google Search: “How Do You Diagnose G6PD (Glucose-6-Phosphate Dehydrogenase) Deficiency”

Today, I review, and link to the results of the Google Search: How Do You Diagnose G6PD (Glucose-6-Phosphate Dehydrogenase) Deficiency.

All that follows is from the above resource.

AI Overview

G6PD deficiency diagnosis involves blood tests, primarily a quantitative G6PD enzyme assay (gold standard) or rapid fluorescent spot tests, to measure enzyme activity, often combined with CBC for signs of anemia and genetic testing for definitive mutation identification, especially for females or family screening. Diagnosis relies on clinical history (triggers like fava beans/medications), blood work showing hemolytic anemia (low hemoglobin, high reticulocytes), and confirming low G6PD enzyme levels, though testing during an acute crisis can be misleading. 

Key Diagnostic Tests

• G6PD Enzyme Assay (Quantitative):

  Measures actual enzyme activity in red blood cells (RBCs); the gold standard using spectrophotometry.

• Fluorescent Spot Test:

  A rapid screening tool (like the Beutler test) that checks if RBCs produce NADPH, failing to fluoresce if deficient.

• Complete Blood Count (CBC):

  Shows signs of hemolytic anemia (low hemoglobin, increased reticulocytes).

• Genetic Testing:

  Identifies specific mutations in the G6PD gene for confirmation, crucial for family studies or ambiguous results.

When Testing is Recommended

• Family history of G6PD deficiency or unexplained anemia.

• Coming from regions where the condition is common (e.g., Africa, Asia, Mediterranean).

• Before starting certain medications (like primaquine).

• Newborn screening in high-prevalence areas.

Important Considerations

• Timing:

  Avoid testing during an acute hemolytic episode as it can give false normal results; repeat testing later is often needed.

• Females:

  Diagnosis can be harder in females due to X-chromosome inactivation; genetic testing or quantitative assays are key.

• Symptoms:

  Look for jaundice (newborns), dark urine, pallor, fatigue, and an enlarged spleen after exposure to triggers like fava beans, infections, or certain drugs.