Diagnostic ultrasound ( PDFDrive )

1632 PART V Pediatric Sonography
A
B
FIG. 48.9 Viral Salivary Gland Infection. (A) Mononucleosis of parotid gland in 10-year-old child. Transverse scan shows a swollen, mildly
inhomogeneous parotid with enlarged intraparotid lymph nodes. (B) Color Doppler comparison sonograms of the submandibular glands shows
decreased echogenicity and increased vascularity in the left and normal appearance of the right.
FIG. 48.10 Bacterial Parotid Infection. Split screen gray-scale and color Doppler images show a swollen, heterogeneous hypervascular parotid
gland in a 17-day-old neonate infected with Staphylococcus.
Inlammatory Lesions
Most salivary gland pathology in children is caused by inlammatory
lesions, which can be acute or chronic. he acute form
may be secondary to viral or bacterial etiologies. he chronic
form includes a long diferential diagnosis (e.g., human immunodeiciency
virus [HIV], Sjögren syndrome, sialoadenitis,
sarcoidosis, other granulomatous processes).
Acute Salivary Gland Inlammation. In children, viral
salivary gland infections are the most common cause of acute
inlammation. 18 Endemic viruses, including mumps, mononucleosis,
and cytomegalovirus (CMV), are the most common viral
causes, causing painful unilateral or bilateral swelling of the
salivary tissue. In 85% of cases, the parotid gland is involved.
Although less prevalent with the advent of immunization, mumps
is still the most common cause of parotitis. 11 Mumps, a highly
contagious worldwide infection spread by airborne droplets, is
typically encountered in the winter and spring and primarily
afects children younger than 15 years. 18 he incubation period
for this virus is 14 to 21 days, but the infection is contagious 3
days before the onset of swelling until the resolution of the
swelling. 19 With ultrasound, viral salivary infections show a
difusely enlarged gland that may have a normal, heterogeneous
and/or hypoechoic echotexture with increased vascularity 20,21
(Fig. 48.9). Frequently there is bilateral involvement, although
unilateral involvement may be seen in up to one-third of patients. 21
Bacterial infection is rare in children, primarily afecting the
parotid gland. Staphylococcus aureus is the most common
cause. 11,15,18,22 Children younger than age 1 year, especially premature
infants (35%-40% cases), immunosuppressed patients,
and children with severe dental and gingival disease are particularly
vulnerable. Infection is typically unilateral and associated
with fever, dehydration, and gland pain and edema. Proposed
etiologies include infection in the mouth or stasis of salivary
low through the ducts. 18 Using ultrasound, the parotid gland
appears enlarged and heterogeneous in echotexture with discrete,
hypoechoic nodules representing enlarged intraparotid lymph
nodes 11-13 (Fig. 48.10). here may be dilation of the central parotid
ducts. 21 Adjacent cervical lymphadenopathy is common. In
patients with uncomplicated parotitis, treatment is primarily