A 5-day-old boy presents with cough and nasal congestion. He is born at 38 weeks' gestation to a primigravida mother via normal vaginal delivery. Antenatal serologies are unremarkable, and the mother is negative for Group B Streptococcus. Apgar scores are 8 and 9 at 1 and 5 minutes, respectively. Birth growth parameters are appropriate for gestational age. The mother reports experiencing an upper respiratory tract infection during the week preceding delivery.Initially, the infant exhibits mild nasal congestion managed with saline nasal washes. At 20 hours of life, jaundice is noted. The mother's blood type was B+, and the infant's was O+. A routine qualitative G6PD test is normal. Total serum bilirubin is 7.8 mg/dL. Direct Coombs test is negative too. Because of unexplained early hyperbilirubinemia, a partial sepsis workup, including complete blood cell count with differential and CRP (C-reactive protein), was performed and demonstrated no abnormalities. The infant receives 1 day of phototherapy and is discharged on day of life 3 without active issues. Intermittent nasal congestion with mild, clear secretions persists during the initial hospital stay, managed with saline nasal washes. He had no cough, breathing difficulties, or feeding problems at that time.The parents report adequate feeding with good sucking ability and no respiratory distress initially. On the day of presentation, the infant develops cough and decreased oral intake. The parents deny observing any choking episodes or gasping noises during feedings.On examination, the infant is alert, active, and moving all extremities well. Vital signs are a temperature of 37.2°C, heart rate of 155 bpm, respiratory rate of 60 breaths per minute, and oxygen saturation at 94% on room air. Profuse, thick, yellowish nasal secretions are present. Auscultation revealed fine crackles bilaterally. No other abnormalities are noted. Transcutaneous bilirubin is elevated at 16.4 mg/dL.The presence of unusual sticky yellowish nasal secretions, diffuse crackles, and unexpectedly nonproportional mild respiratory distress prompted a specific test that clinched the diagnosis.The infant is admitted to the neonatal intensive care unit for management of respiratory symptoms and hyperbilirubinemia. Shortly after admission, the oxygen saturation drops to 88% on supplemental oxygen via nasal cannula and is placed on nasal continuous positive airway pressure (CPAP) with a positive end-expiratory pressure of 6 cmH2O and an FiO2 of 0.25, which stabilizes oxygen saturation above 95%.Initial workup includes a normal complete blood count with differential, negative CRP and procalcitonin, normal electrolytes, normal renal function, and sterile blood culture. Chest radiography demonstrates bilateral prominent bronchovascular markings, central peribronchial cuffing, and patchy, faint linear infiltrates located in the right and left lower lobes as well as the left upper lobe (Figure 1).When evaluating a neonate with respiratory symptoms, several diagnoses should be considered, including in this case bacterial pneumonia, viral pneumonia, bronchiolitis, congenital anomalies, aspiration pneumonia, and atypical bacterial pneumonia.Given the unusual, profuse, sticky, and yellowish nasal secretions, a nasopharyngeal swab for a respiratory polymerase chain reaction (PCR) panel is performed just before admission that detects Mycoplasma pneumoniae, an unexpected pathogen in this age group. The mother's nasopharyngeal swab PCR is negative when done after admission.The infant is started on oral azithromycin at 10 mg/kg/d, and phototherapy is initiated for hyperbilirubinemia. Over 48 hours, the infant shows significant clinical improvement, with gradual weaning from CPAP to room air. Feeding tolerance improves gradually, and bilirubin levels decrease with phototherapy. The infant completes a 5-day course of azithromycin and is discharged in stable condition with normal vital signs, including oxygen saturation of 98% on room air.Mycoplasma pneumoniae is an atypical bacterial pathogen primarily recognized as a cause of community-acquired pneumonia in school-aged children and young adults.1Mycoplasma pneumoniae infection in neonates is exceedingly rare, with few documented cases in the literature.2,3 The organism lacks a cell wall, rendering it naturally resistant to beta-lactam antibiotics.4This case represents a rare presentation of Mycoplasma pneumoniae infection in a neonate, likely acquired through vertical transmission from the mother, who exhibited respiratory symptoms in the peripartum period. Although Mycoplasma pneumoniae is primarily transmitted via respiratory droplets, vertical transmission has been documented in rare instances, but the exact mechanism remains unclear.5 The negative maternal PCR could indicate clearance of the infection or a false-negative result.The clinical presentation of Mycoplasma pneumoniae infection in neonates differs from that in older children.6 Our patient's presentation with nasal congestion and mild respiratory symptoms initially mimicked a typical viral upper respiratory tract infection, which made the diagnosis challenging. Additionally, since the first day of life, he has had nasal congestion that is most likely related to the infection but has passed unnoticed.Diagnostic confirmation of Mycoplasma pneumoniae infection traditionally relied on serological testing, which has limitations in neonates because of maternal antibodies and an immature immune response. PCR testing of respiratory specimens has emerged as the gold standard for diagnosis, offering improved sensitivity and specificity.7Treatment of Mycoplasma pneumoniae infection in neonates presents a therapeutic challenge. Macrolides, including azithromycin, are the drugs of choice, but their use in neonates requires careful consideration of safety, dosing, and efficacy. The recommended dosage for azithromycin in neonates with Mycoplasma pneumoniae infection is 10 mg/kg/d for 5 to 7 days.8 Alternative antibiotics such as fluoroquinolones or tetracyclines are generally avoided in this age group because of potential adverse effects. With the increasing risk of resistance, especially to azithromycin after overuse during the COVID-19 pandemic, the other alternatives can be considered as off-label, especially in case of clinical deterioration.Our patient responded well to oral azithromycin therapy, showing clinical improvement within 48 hours of initiation. This aligns with previous case reports that documented good outcomes with early macrolide therapy in neonatal Mycoplasma pneumoniae infections.9 The concomitant hyperbilirubinemia in our patient was managed with phototherapy and likely represented a combination of physiologic jaundice and the mild hemolytic effect occasionally associated with Mycoplasma infections.10Mycoplasma pneumoniae should be considered in the differential diagnosis of neonates with respiratory symptoms, particularly with a maternal history of respiratory illness and when symptoms are refractory to standard treatments for more common neonatal respiratory conditions.Vertical transmission of Mycoplasma pneumoniae can occur and should be suspected when mothers exhibit respiratory symptoms in the peripartum period.Nasopharyngeal PCR is a valuable diagnostic tool for identifying atypical respiratory pathogens in neonates.Early diagnosis and appropriate antimicrobial therapy typically result in favorable outcomes in neonatal Mycoplasma pneumoniae infections.American Board of Pediatrics Neonatal–Perinatal Content SpecificationRecognize neonatal bacterial infections.Understand infections of the respiratory system and respiratory distress syndrome.
Hassoun et al. (Mon,) studied this question.