1. What is the I/T Ratio?

The I/T (Immature/Total) ratio is a calculation used in neonatal medicine to assess the maturity of white blood cells. It compares the number of immature neutrophils to the total neutrophil count, providing valuable information about infection and inflammatory status in newborns.

2. How Does the Calculator Work?

The calculator uses the I/T ratio formula:

Where:

• \( Immature\ Count \) — Number of immature neutrophils
• \( Total\ Count \) — Total neutrophil count (mature + immature)

Explanation: The ratio provides a simple yet effective way to quantify the proportion of immature neutrophils in the total neutrophil population, which is particularly useful in neonatal sepsis evaluation.

3. Importance of I/T Ratio Calculation

Details: The I/T ratio is a valuable screening tool for early detection of neonatal infections. An elevated ratio (>0.2) often indicates bacterial infection and may prompt further diagnostic testing and early intervention in newborns.

4. Using the Calculator

Tips: Enter the immature neutrophil count and total neutrophil count. Both values must be valid (immature count ≤ total count, total count > 0). The calculator will compute the ratio automatically.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal I/T ratio in newborns?
A: In healthy term infants, the I/T ratio is typically less than 0.2. Values above 0.2 may suggest infection and require clinical correlation.

Q2: When should I/T ratio be measured?
A: The I/T ratio is most commonly used in the evaluation of neonates with suspected sepsis, particularly in the first 72 hours of life when clinical signs may be subtle.

Q3: Are there limitations to the I/T ratio?
A: While useful, the I/T ratio should be interpreted in clinical context. It may be elevated in non-infectious conditions such as perinatal stress, maternal fever, or meconium aspiration.

Q4: How accurate is the I/T ratio for detecting sepsis?
A: The I/T ratio has good sensitivity (approximately 60-90%) for early-onset sepsis but should be used as part of a comprehensive sepsis evaluation including clinical assessment and other laboratory markers.

Q5: Can I/T ratio be used in preterm infants?
A: Yes, though normal values may differ slightly. Preterm infants may have slightly higher baseline I/T ratios, and interpretation should consider gestational age and clinical context.