Diagnostic ultrasound ( PDFDrive )

1660 PART V Pediatric Sonography
A
B
C
FIG. 48.52 Internal Jugular Phlebectasia.
Child was referred because
of bluish pulsation beneath the skin.
(A) Transverse ultrasound of the carotid
and jugular vein with Valsalva shows
dilation of the internal jugular vein. (B)
Without Valsalva, the internal jugular
vein is smaller in caliber, but still ectatic.
(C) Longitudinal image again shows
ectasia of the internal jugular vein.
istulas may develop. 45 FNA and surgical incision may be necessary
to resolve the infection. 187
Acute lymph node enlargement in children can be unilateral
or bilateral. he anterior cervical nodes, which drain the mouth
and pharynx, are most oten afected. 187 In 80% of cases, acute
unilateral pyogenic lymphadenitis is secondary to S. aureus or
group A beta-hemolytic streptococci. 74,187,191 Many patients have
respiratory tract infection, pharyngitis, tonsillitis, or otitis media
in conjunction with tender, warm, and erythematous lymph
nodes. A less common cause of acute bacterial lymphadenitis
includes actinomycosis in a patient with poor dental hygiene.
he etiology of bilateral cervical lymphadenopathy tends
to be viral, including rhinovirus, parainluenza virus, and
inluenza. 191 Epstein-Barr virus can be diicult to diferentiate
from bacterial infections because the infection may be associated
with exudative tonsillitis. In a patient with Epstein-Barr virus,
the presence of difuse lymphadenopathy and hepatosplenomegaly
may help conirm the diagnosis. 5 Noting the age of the child
and the sites involved may provide other clues 192 (Tables 48.3
and 48.4).
Subacute or chronic infection occurs when cervical lymph
nodes enlarge slowly and are only minimally tender without
substantial cellulitis. Diferential diagnosis includes bacterial
causes such as atypical mycobacteria, Mycobacterium tuberculosis,
Nocardia, or cat-scratch disease; viral pathogens; or fungal
infection such as histoplasmosis. 187,190 Most mycobacterial infections
are caused by variant strains of Mycobacterium aviumintracellulare-scrofulaceum
complex. 187 Infection typically is
unilateral and occurs in children aged 1 to 5 years. M. tuberculosis,
when it involves the cervical nodes, is thought to represent an
extension of the primary pulmonary lesion or to be associated
with acquired immunodeiciency syndrome (AIDS). 45 Nodes on
sonography with low attenuation centers and small calciications
suggest mycobacterial infection. 77,144 Nocardia typically is seen