99391
Periodic preventive medicine re-evaluation and management, established patient; infant (age younger than 1 year)
CPT 99391 is a comprehensive preventive medicine evaluation and management (E/M) service for an established patient who is an infant, specifically defined as a child younger than one year of age. This code represents a well-child visit where the primary focus is health maintenance, disease prevention, and the monitoring of normal developmental milestones. The service encompasses several distinct components: an age-appropriate history, a comprehensive physical examination, counseling or anticipatory guidance, and the ordering of appropriate laboratory or screening tests. The history typically involves reviewing the interval history since the last visit, feeding patterns (breastfeeding or formula), sleep hygiene, elimination patterns, and parental concerns. The physical examination is multisystem and thorough, including the measurement of length, weight, and head circumference, which are then plotted on standardized growth charts to monitor trends. A developmental assessment is performed to ensure the infant is meeting age-specific cognitive and motor milestones. Anticipatory guidance is a critical element, where the provider discusses safety (e.g., car seats, safe sleep environments), nutrition, and what to expect in the coming months. This code is specifically for established patients; if the infant is new to the practice, code 99381 would be used instead. It is important to note that immunizations and certain standardized screening instruments (such as formal developmental or behavioral screens) are not bundled into this code and should be reported separately. If a significant, separately identifiable acute or chronic illness is addressed during the same encounter, an additional E/M code (99212-99215) may be reported with modifier 25.
Clinical Indications
- Routine well-child examination for an infant under 12 months
- Monitoring of physical growth (weight, length, head circumference)
- Assessment of developmental milestones
- Nutritional counseling and breastfeeding/formula guidance
- Review and update of immunization status
- Anticipatory guidance regarding safety and injury prevention
- Screening for behavioral or social-emotional concerns in the family environment
Procedure Steps
- Obtain an age-appropriate history including birth history and interval health status
- Review nutritional intake and growth patterns
- Perform a comprehensive multisystem physical examination
- Measure and record anthropometric data (weight, length, head circumference)
- Conduct a developmental surveillance assessment
- Provide age-specific anticipatory guidance (e.g., SIDS prevention, car seat safety)
- Review and provide recommendations for the immunization schedule
- Order or perform indicated screening tests (e.g., lead, hemoglobin, or metabolic screens)
- Coordinate follow-up care or referrals to specialists if abnormalities are identified
Coding Guidelines
- Code 99391 is exclusively for established patients under the age of 1 year.
- Do not report 99391 for a new patient; use 99381 for the initial preventive visit.
- Immunization administration and the vaccine products are reported separately from the preventive medicine service.
- Standardized screening instruments (e.g., 96110 for developmental screening) are reported separately.
- If a separate medical problem is addressed that requires significant additional work, report the appropriate office visit code (99212-99215) with modifier 25.
- Preventive medicine codes are not time-based; they are based on the age and status of the patient.
- The comprehensive nature of the exam and history is required; it is not defined by the three key components of sick-visit E/M codes.