Should a 4-month-old infant with an ear tag and no audible murmur undergo an echocardiogram (echo) and ultrasound of the kidneys, ureters, and bladder (USG KUB) as part of their diagnostic workup?

Echocardiography and Renal Ultrasound in a 4-Month-Old with Ear Tag and No Murmur

An echocardiogram is NOT indicated in this 4-month-old infant with an isolated ear tag and no audible cardiac murmur, as the absence of a murmur or other abnormal cardiac findings makes this a Class III indication (not appropriate) according to ACC/AHA guidelines. 1 However, hearing assessment is strongly recommended given the significantly elevated risk of hearing impairment associated with preauricular tags. 2, 3 Renal ultrasound should be considered if there are additional congenital anomalies or clinical concerns, but is not routinely indicated for an isolated ear tag alone. 1

Cardiac Evaluation Decision Algorithm

When Echocardiography IS Indicated (Class I - Strongly Recommended)

ACC/AHA guidelines specify that echocardiography is definitively indicated for: 1, 4

• Cyanosis, respiratory distress, or abnormal arterial pulses in a neonate 1, 4
• Loud or abnormal murmur in an infant or older child 1, 5
• Failure to thrive with abnormal cardiac findings 1, 4
• Cardiomegaly on chest radiograph 1, 6
• Most ECG abnormalities 1
• Presence of a syndrome associated with heart disease 1, 4

When Echocardiography IS NOT Indicated (Class III - Not Appropriate)

ACC/AHA guidelines explicitly state that echocardiography is not appropriate for: 1

• An asymptomatic heart murmur in a child that is positively identified by an experienced observer as functional or innocent 1
• By extension, no murmur at all in an otherwise asymptomatic child 1

Critical Distinction for This Case

The key clinical finding is that no murmur is currently heard. 1 While history and physical examination by a skilled observer are usually sufficient to distinguish functional from pathologic murmurs, the complete absence of a murmur in an otherwise asymptomatic infant with only an isolated ear tag does not meet criteria for echocardiography. 1

Hearing Assessment - STRONGLY RECOMMENDED

Evidence for Hearing Evaluation

All infants with preauricular tags or pits require hearing assessment, as they have a significantly elevated risk of permanent hearing impairment: 2, 3

• Prevalence of hearing impairment: 8 per 1,000 infants with ear tags/pits versus 1.5 per 1,000 without (odds ratio 4.9 after risk adjustment) 3
• In low-risk infants specifically: 3.4 per 1,000 with tags/pits versus 0.5 per 1,000 without 3
• Hearing impairment types detected: Both conductive and sensorineural 2

Recommended Hearing Assessment Protocol

For a 4-month-old infant, the diagnostic audiological test battery should include: 1

• Auditory brainstem response (ABR) testing using air-conducted tone bursts for frequency-specific assessment 1
• Click-evoked ABR testing using both condensation and rarefaction stimuli 1
• Otoacoustic emissions (OAE) testing - transient evoked or distortion product 1, 3
• Tympanometry using a 1000-Hz probe tone (appropriate for infants under 6 months) 1
• Clinician observation of the infant's auditory behavior 1

Timing Considerations

• Hearing loss should be confirmed by no later than 3 months of age per AAP/JCIH guidelines 1
• At 4 months, this infant is slightly beyond the ideal window but should still undergo immediate comprehensive audiological evaluation 1
• If hearing loss is confirmed, amplification should be fitted within 1 month of diagnosis 1

Renal Ultrasound Considerations

When Renal Imaging IS Indicated

Renal ultrasound (USG KUB) should be performed if: 1

• Multiple congenital anomalies are present (19% of infants with ear tags have associated anomalies) 2
• Clinical signs suggesting renal involvement (hematuria, proteinuria, hypertension, palpable masses) 1
• Syndromes associated with renal anomalies (e.g., branchio-oto-renal syndrome, CHARGE syndrome) 1

When Renal Imaging May NOT Be Indicated

For an isolated ear tag without other anomalies or clinical concerns: 1, 2

• ACR Appropriateness Criteria do not specifically address isolated ear tags as an indication for renal imaging 1
• The 19% rate of associated anomalies in one study suggests careful physical examination is warranted, but routine renal imaging for isolated ear tags is not standard 2

Clinical Caveat

Perform a thorough physical examination looking for other congenital anomalies before deciding on renal imaging. 1, 2 If the ear tag is truly isolated with normal growth, development, and physical examination, renal ultrasound may be deferred with close clinical follow-up. 1, 2

Summary Algorithm for This Case

1. Echocardiogram: NOT indicated - No murmur and no other cardiac findings 1
2. Hearing assessment: STRONGLY indicated - Comprehensive audiological evaluation including ABR 1, 2, 3
3. Renal ultrasound: Consider based on complete physical examination - Indicated if additional anomalies present; may defer if truly isolated ear tag 1, 2