Abstract
Neonatal suppurative parotitis is very rare. One review of the English-language literature spanning 35 years found only 32 cases. Most cases are managed conservatively with antibiotic therapy; early antibiotic treatment reduces the need for surgery. The predominant organism is Staphylococcus aureus. We report a new case of neonatal suppurative parotitis in a 3-week-old boy. The patient was diagnosed on the basis of parotid swelling, a purulent exudate from a Stensen duct, and the growth of pathogenic bacteria in culture. He responded well to 9 days of intravenous antibiotic therapy. We also discuss the microbiologic and clinical patterns of this disease.
Introduction
Neonatal suppurative parotitis is an uncommon disease, with an incidence of 3.8/10,000 hospital admissions for neonates. 1 Spiegel et al reviewed the English-language literature spanning 35 years and found only 32 cases. 1 We describe a new case of neonatal suppurative parotitis, and we discuss its microbiologic and clinical patterns.
Case report
A 3-week-old, full-term boy with no perinatal complications presented with a 1-day history of restlessness, irritability, reduced feeding, and increased frequency of stool. His mother had also noticed redness and swelling in the left preauricular area, which was tender to touch. The neonate was admitted to the hospital. His weight was 4.16 kg (9.17 lb), his fontanelles were normal, and his temperature was 37.2°C (98.96°F). Examination revealed a 2 × 3-cm erythematous swelling in the left preauricular area; the skin over the area was warm and tender. Intraorally, pus was seen exuding from the left Stensen duct. Findings on the reminder of the physical examination were unremarkable.
A swab of the pus was taken for culture and sensitivity analysis. Laboratory tests revealed a hemoglobin level of 16.7 g/dl, an erythrocyte sedimentation rate of 20 mm/ hr, and a white blood cell count of 15.9 × 10 9 /L with a differential of 58% neutrophils, 28% lymphocytes, and 8% monocytes. Ultrasound examination of the swelling demonstrated an enlarged left parotid gland with multiple hypoechoic areas, findings that are consistent with parotitis. No evidence of abscess collection or significant adenopathy was detected.
Based on the clinical presentation and ultrasound findings, the patient was diagnosed with acute suppurative parotitis. He was treated with intravenous flucloxacillin (not available in the U.S.) at 200 mg/kg/day and gentamicin at 5 mg/kg/day. After 48 hours, the erythema, edema, and other symptoms had resolved. His breast-feeding and sleep patterns returned to normal, and treatment was continued for 7 more days. A heavy growth of Staphylococcus aureus was seen on culture.
Discussion
Neonatal suppurative parotitis appears to affect normal healthy infants who become colonized by bacteria within the first few days of life. The skin and umbilicus are the first sites of contamination, which then spreads to the nose and nasopharynx. The oral cavity gradually becomes colonized with alpha-hemolytic streptococci in 90% of cases and staphylococci in 5 to 10%. 2
The most commonly reported causative organism in neonatal suppurative parotitis is S aureus. In 2002, MacDorman et al reported that S aureus was the culprit in 55% of cases. 3 Less frequently isolated organisms were Streptococcus viridans, Streptococcus pyogenes, Peptostreptococcus spp, and coagulase-negative staphylococci (a combined 22% of cases). Gram-negative bacilli (16%) and anaerobic bacteria (4%) were also found. In 2005, 2 cases of neonatal suppurative parotitis were reported in the German literature, both in 2-week old patients.4,5 In both cases, the infection was caused by S aureus.
The parotid gland is purely serous and very susceptible to infection secondary to stasis and dehydration—unlike the submandibular gland, which is a mixed serous and mucous gland with a mucus content that has bacteriostatic properties. 2 Premature neonates present special problems. It is not uncommon for a premature neonate to be dehydrated. Dehydration of the oral mucosa can predispose a neonate to ascending infection of the parotid. As is the case among neonates overall, the most common bacteria involved in premature neonates is S aureus.3,6
The presence of purulent discharge expressed from a Stensen duct is considered pathognomonic of acute neonatal suppurative parotitis. Other typical signs and symptoms include parotid gland swelling, tenderness, erythema, and warmness. Characteristic laboratory findings include a positive culture for bacteria and an increased white blood cell count with a predominance of neutrophils. 7
In infants with an unusual clinical presentation, ultrasound examination can help guide the diagnosis.2,8,9 Ultrasonography is helpful when making a specific diagnosis such as sialectasis. It can also help determine whether a parotid swelling has arisen secondary to enlargement of adjacent tissue or to the presence of an intraparotid mass, including an abscess.9,10
Most cases of neonatal suppurative parotitis are managed conservatively with antibiotic therapy.1,8 Early antibiotic treatment reduces the need for surgery.7,11 The optimal duration of therapy is unknown, but our experience, and that of others, suggests 7 to 10 days or at least until the lesion has resolved. If prompt clinical improvement does not occur or if the swelling becomes fluctuant, incision and drainage should be performed. 8
Historically, the reported complications of neonatal suppurative parotitis include salivary fistula, facial palsy, deep neck space infections, mediastinitis, and extension of the infection into the external ear, all of which are associated with a poor prognosis. However, during the past 2 decades, most affected patients have achieved a rapid and complete recovery with the early use of parenteral antibiotics.1,2,9