A previous blog post (NAFLD Guidelines 2012) described comprehensive, up-to-date NAFLD guidelines from AASLD, AGA, and ACG. Another group of experts from ESPGHAN (European Society for Pediatric Gastroenterology, Hepatology, and Nutrition) has also published a position paper on the diagnosis of NAFLD in children; coincidentally, these were published recently as well (JPGN 2012; 54: 700-13).
While there is some overlap in the information between the two guidelines, there are some notable differences. The JPGN manuscript does include a nice differential diagnosis list which can cause fatty liver disease (Table 2), including some rare entities like Dorfman-Chanarin syndrome, Cantu syndrome, Madelung lipomatosis, and numerous medications. This review has more emphasis on etiology.
Table 3 lists a recommended workup in children with suspected NAFLD:
- Standard liver function tests/blood counts/coagulation studies
- Fasting glucose & insulin
- Lipid profile
- Glucose tolerance test & glycosylated hemoglobin
- Calculation of HOMA-IR, markers of insulin resistance
AND Tests to exclude other liver diseases:
- Lactate, uric acid, iron, ferritin, pyruvate
- Copper, ceruloplasmin, 24-hour urinary copper
- Sweat test
- Celiac serology (TTG IgA and serum IgA)
- α-1-antitrypsin levels and phenotype when indicated
- Amino and organic acids
- Plasma free fatty acids and acyl carnitine profile
- Urinary steroid metabolites
- Other specific tests as suggested by evaluation (eg. viral hepatitis panel, serum immunoglobulins, liver autoantibodies)
When one looks at the recommended diagnostic algorithm (Figure 1) and tests outlined, these guidelines are not nearly as practical as the NAFLD guidelines from AASLD, AGA, and ACG and often contradictory between the tables/figures and the text. How much would it cost for the recommended testing if/when extrapolated to the vast numbers of individuals with these disorders? In addition, a much more limited diagnostic approach is suggested in the final section than outlined in Table 3 and Figure 1.
Imaging: these authors advocate LFTs and ultrasonography in all obese children (> 3 years) and adolescents. If normal LFTS and sonography, the algorithm suggests the use of MRI if clinical signs of insulin resistance. Later, the authors conclude “MRI is not cost-effective.”
Liver Biopsy: while the authors state that there is “no present consensus or evidence base to formulate guidelines” for liver biopsy, this is not well-reflected in their diagnostic algorithm in which arrows point to liver biopsy in almost everyone –either early liver biopsy or eventual biopsy in patients with persistent disease. Accepted liver biopsy indications, according to the executive summary, include the following:
- Exclude other treatable disease
- Suspected advanced disease
- Before pharmaceutical/surgical treatment
- Research purposes
My conclusion about this position paper is it is less helpful than the AASLD/AGA/ACG guidelines. In fact, when extensive diagnostic testing is recommended by experts, it is fortunate that other expert guidelines are available that support a more cost-effective approach. In NAFLD cases that seem atypical and especially in the very young patient, this reference may still be helpful.