Pediatric emergency medicine trisk 520
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given empirically, with coverage directed toward enteric organisms. Blood
cultures should be drawn prior to antibiotic administration.
ALAGILLE SYNDROME
AS is another cause of cholestasis in a newborn or infant, and is secondary to
bile duct paucity. AS is a progressive disorder. Infants with AS may not have
biliary paucity if their biopsy is performed before 6 months of life. In contrast,
90% of infants over 6 months of age will demonstrate biliary paucity on
biopsy. The majority (95%) of patients less than 1 year of age will
demonstrate cholestasis on laboratory evaluation, while their synthetic
function is typically intact. Hepatomegaly under 1 year of age is common.
Over months to years, however, patients’ hepatic disease tends to worsen as
the biliary tract deteriorates. With time, 10% to 50% of patients who initially
present in infancy will develop severe portal hypertension, cirrhosis, or liver
failure and 20% to 50% will require liver transplant.
In addition to bile duct paucity, AS is associated with three of five clinical
features: cholestasis, cardiac skeletal, ocular abnormalities, and characteristic
facies (Verkade, 2016) ( Table 91.4 ). Additional genetic mutations have been
associated with AS, and aids in the diagnosis. On physical examination, ED
providers may see syndromic facies, jaundice, excoriations secondary to
extreme pruritus, hepatosplenomegaly, stigmata of portal hypertension ( Table
91.2 ), xanthomas, heart murmur, or sequelae of congenital heart disease, such
as cyanosis. In addition to cholestatic disease, congenital heart disease is the
most common abnormality seen in AS, and is the highest cause of mortality in
infancy. It may be seen in as many as 90% of patients with AS. The most
common types of congenital heart disease include pulmonic valve stenosis,
tetralogy of Fallot, pulmonary atresia, truncus arteriosus, ASD, and VSD. The
mortality rates of patients with tetralogy of Fallot and AS are higher than
patients without AS. Intracranial bleeding is also common in patients with AS
and is a major cause of mortality. Renal disorders are very common in AS,
occurring in about 40% to 50% of patients. These include, but are not limited
to, renal artery stenosis, solitary kidney, dysplastic kidneys, renal tubular
acidosis, and juvenile nephronophthisis.
There are many reasons for an infant to present with cholestasis, and the ED
provider who is treating a patient with, or suspected of AS, must understand
the high potential for additional congenital abnormalities in addition to liver
disease. While phenotypes and congenital abnormalities can vary greatly, it is
the comorbidities that are the likely cause for morbidity and mortality in the
infancy period.
TABLE 91.4
CHARACTERISTICS OF ALAGILLE SYNDROME
Classic Alagille syndrome criteria
1. Bile duct paucity plus
2. 3 of 5 major criteria:
• “Alagille Facies”
• Cholestasis (conjugated hyperbilirubinemia)
• Congenital heart disease
• Vertebral anomalies
• Ocular anomalies
Additional clinical characteristics
Hepatic: chronic cholestasis, portal hypertension, liver fibrosis, liver
cirrhosis, liver failure, hepatocellular carcinoma
Cardiac: tetralogy of Fallot, pulmonic valve stenosis, pulmonary atresia,
truncus arteriosus, aortic stenosis, ASD and VSD
Ocular: posterior embryotoxon, Axenfeld anomaly, Rieger anomaly,
congenital macular dystrophy, cataracts, exotropia, strabismus, retinal
fundus hypopigmentation
Vertebral: butterfly vertebrae, shortened digits, spina bifida occulta, fusion
of adjacent vertebrae, rickets, osteopenia/osteoporosis, pathologic
fractures
Facial features: prominent forehead, macrocephaly, hypertelorism, deep set
eyes, upslanting palpebral fissures, depressed nasal bridge, sinus
abnormalities, large ears
Renal: renal tubular acidosis, renal insufficiency,
small/ectopic/horseshoe/single kidneys, renal cysts
Vascular: stroke, intracranial bleeding, cerebral artery anomalies, vascular
malformations, moyamoya syndrome, renal artery stenosis
Endocrine: pancreatic exocrine insufficiency, insulin-dependent diabetes
mellitus, hypogonadism
Gastrointestinal: malabsorption, failure to thrive, malrotation, microcolon,
atresia
Other: growth retardation, mental retardation, learning difficulties
