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neonates born to mothers not previously exposed to pertussis or with inadequate vaccination These neonates will not have passive immunity from maternal antibodies It can present either as an early- or late-onset pneumonia after contact with an infected family member or sibling Neonates with pneumonia present with respiratory distress and increase in nasal and respiratory secretions Signs and symptoms similar to neonatal sepsis can be nonspecific ( Table 96.7 ) Viral infection with RSV, influenza, parainfluenza viruses, adenovirus, and metapneumovirus can produce a similar presentation Apnea is a common presentation in RSV infection All neonates with suspected pneumonia should receive a complete workup, including CBC, CRP, blood, urine, and CSF cultures CXR may show patchy infiltrates with air bronchograms, diffuse haziness, or lobar or segmental consolidation Pleural effusions are common but CXRs may also be normal in 15% of cases CXR in babies with C trachomatis may show hyperinflation with infiltrates Nasopharyngeal aspirates can be sent for direct immunofluorescence or PCR to diagnose chlamydial pneumonia Neonatal pneumonia should be differentiated from other pulmonary etiologies (pneumothorax) and nonpulmonary etiologies of respiratory distress (e.g., choanal atresia, tracheoesophageal fistula, CHD, and metabolic etiologies) Empiric treatment with broad-spectrum antibiotics is indicated similar to neonatal sepsis Supportive treatment including intravenous fluids, correction of electrolyte disturbances, and respiratory support should be initiated as needed Therapy should be tailored according to the organism Oral erythromycin or azithromycin is indicated for chlamydial infection Mothers and their partners should also be treated Infants born through a vaginal canal infected with chlamydia are at high risk of contracting pneumonia or conjunctivitis They should be observed for emergence of signs and symptoms Efficacy of antibiotic prophylaxis is unknown Urinary Tract Infections in the Newborn UTIs occur in 0.1% to 1% of neonates They are more common in uncircumcised males because of limited retraction and increased bacterial burden in the foreskin This holds true up to year of age, after which the incidence is higher in females E coli is responsible for 50% to 80% of UTIs E coli has increased virulence factors that facilitate adherence and propagation of the organisms Other gramnegative bacteria can be etiologic agents but gram-positive organisms may also contribute Infectious spread to the urinary system can occur hematogenously from bacteremia (30% of cases) or from an ascending infection Twenty to 50% of neonates who develop a UTI will have a congenital abnormality of the genitourinary tract that facilitates stasis of urine or propagation of bacteria (e.g., hydronephrosis, posterior urethral valves, ectopic ureter, duplication of the collecting system, renal dysplasia) VUR may be the only abnormality Signs and symptoms are similar to those of neonatal sepsis ( Table 96.7 ) Fever and poor feeding are the most common presenting symptoms Direct hyperbilirubinemia, prolonged jaundice, or new onset of jaundice in a newborn after days of life is suspicious for a UTI One percent to 2% of babies with UTI will develop meningitis Neonates suspected of having a UTI should undergo a full sepsis workup including blood, urine, and CSF cultures Urinalysis alone for diagnosis of UTI lacks specificity and sensitivity Infants frequently void, which does not allow for an adequate concentration of nitrites or leukocyte esterase to form in the urine Urine culture should be obtained by catheterization or suprapubic aspiration and not from a bagged specimen Presence of more than 10,000 colony-forming units/mL in a catheterized urine culture with positive urinalysis or dipstick is significant Neonates should be admitted for observation and intravenous antibiotics after obtaining cultures Other Viral Infections of the Newborn Neonates often develop specific viral infections that have characteristic manifestations different from bacterial infection The goal of treatment is to determine differences between these viral infections and neonatal sepsis Often this is not possible until after admission and testing CLINICAL PEARLS AND PITFALLS Sixty percent to 80% of mothers who transmit HSV to their newborns have not had a history of a prior genital infection Consider HSV in neonates who have abnormal liver function tests Enteroviral infections are more severe in the neonate than children resulting in meningitis, acute fulminant hepatitis, and heart failure from myocarditis Consider sending enteroviral PCR from a CSF sample in babies with signs and symptoms of neonatal sepsis and high liver functions Neonatal Herpes Simplex Virus Infection Neonatal HSV disease can result from infection with HSV-1 or HSV-2 It is still very rare, occurring in only 1:3,200 deliveries Infection occurs through vertical transmission in utero (congenital infection) (5%), or while passing through an infected birth canal (intrapartum) (85%), or from contact with infected oral secretions (postpartum) (10%) Maternal HSV infection can be described as first-episode primary infection, first-episode nonprimary infection, and recurrent infection First-episode primary infections occur in mothers who have never been previously exposed to infection First-episode nonprimary infections occur when a mother has had HSV-1 previously and then becomes infected with HSV-2 (or vice versa) since HSV-1 and HSV-2 share significant cross reactivity Recurrent maternal infection implies that the mother has had a previous exposure and has formed protective antibodies that are conveyed to the baby but is having a reactivation Recurrent infections are responsible for 50% of the cases of neonatal HSV because recurrent maternal outbreaks occur more commonly than primary infections However, primary infections are more severe in nature than recurrent episodes due to the absence of maternal antibodies and shedding of higher quantities of HSV for longer periods of time About 30% of pregnant women will have serologic evidence of HSV-2, the majority without prior history of symptoms or infection Complete perinatal history may reveal the occurrence of genital outbreaks before or shortly after birth History of contact with a person who has had cold sores or presence of breast lesions in breast-feeding mothers may be helpful Maternal history of a genital infection is often unclear due to the possibility of asymptomatic or subclinical infections It is estimated that 60% to 80% of women whose infants develop HSV not have a prior history of genital infection or symptoms Mothers with a history of recurrent HSV infection have a 2% chance of transmitting infection to their newborn at delivery during active shedding The chance of transmission increases to 57% in first-episode primary maternal infection and 25% in first-episode nonprimary infection History may also reveal the presence of risk factors such as a primary infection, vaginal delivery, prolonged rupture of membranes (>4 to hours), use of fetal scalp electrode, or disruption of the skin during vacuum extraction HSV disease in neonates is usually symptomatic It can present in two forms: (a) Congenital HSV infection from an in utero transmission (characterized by vesicular skin lesions, or scarring, neurologic lesions [microcephaly, hydranencephaly, intracranial calcifications, hypertonicity, or seizures] and ocular findings [chorioretinitis, microphthalmia, cataracts, or optic atrophy]) or (b) neonatal HSV, which may present to weeks after discharge from the newborn nursery Neonatal HSV, like neonatal sepsis, can have nonspecific symptoms ( Table 96.7 ) Neonatal HSV classically produces three presentations (skin, eyes, mouth [SEM] [45%], CNS disease [30%], or disseminated HSV [25%]) Fever occurs in 30% of neonates with HSV, whereas 20% present with hypothermia While HSV is uncommon, the overall incidence of HSV in febrile neonates is approximately 1% Neonates presenting with fever, irritability, and CSF pleocytosis should be worked up for HSV disease, particularly if seizures occur SEM disease presents with vesicular eruptions usually 10 to 12 days after birth Clusters of vesicles appear on the skin and mucous membranes without involvement of any other organ system, particularly the scalp for neonates born with cephalic presentations Herpetic keratitis can lead to corneal scarring CNS disease presents with mucocutaneous lesions that appear around 17 to 19 days, as well as neurologic manifestations (seizures, bulging anterior fontanelle, and lethargy) Absence of skin lesions does not rule out CNS disease; 30% to 60% of infants with CNS disease not have mucocutaneous lesions Neonates with disseminated disease typically present at about 10 to 12 days with septic shock These infants have the worst prognosis Multiple organ systems involvement produces acute hepatitis, respiratory distress, pneumonia, pleural effusions, adrenal disease, neurologic manifestations, pneumatosis intestinalis, and disseminated intravascular coagulopathy Again, absence of skin lesions (up to 40%) does not exclude disseminated disease Neonates suspected of having HSV disease should undergo a full sepsis workup including CBC, urinalysis and urine culture, blood culture, liver functions, lumbar puncture, and HSV cultures Isolation of HSV by culture (blood, CSF, and surface cultures) (swabbing the conjunctiva, mouth, nasopharynx, and ending with the rectum then placing swabs in one viral media containing tube) remains the definitive diagnostic method HSV cultures can be obtained from skin lesions Diagnosis of HSV can also be confirmed by PCR from CSF samples CSF PCR for HSV should be accompanied by surface cultures CSF will show mild pleocytosis with abundant mononuclear cells, elevated protein level, normal glucose concentration, and a negative Gram stain Infants suspected of having any form of HSV disease, even SEM, should have a lumbar puncture performed Blood HSV PCR can also be obtained but not enough data are available to recommend its routine use Liver functions may show elevated alanine aminotransferase (ALT) Electroencephalogram (EEG) may show nonspecific findings but occasionally temporal lobe seizures may be seen Transfer of maternal antibodies makes serologic tests in neonates difficult to interpret and therefore not useful