Roux-en-Y Gastric Bypass as a Treatment for Hepatic Iron Overload: An Exploratory Study

Identification of Predictors of Non-alcoholic Steatohepatitis and Its Severity in Individuals Undergoing Bariatric Surgery

BACKGROUND

As obesity reached epidemic proportions, non-alcoholic fatty liver disease (NAFLD) also had a worrisome parallel increase. The non-invasive differentiation of non-alcoholic steatohepatitis (NASH) from uncomplicated NAFLD remains an important challenge in current clinical practice.

OBJECTIVE

To identify predictors of the occurrence and severity of NAFLD and NASH.

METHODS

This is an analytical cross-sectional study which included individuals undergoing bariatric surgery. Participants were histologically classified according to the presence NASH and severity of NAFLD. Demographic, clinical, anthropometric, and biochemical aspects were analyzed and compared.

RESULTS

Out of 171 individuals, 87.7% were female and the mean age was 38.4±9.3 years. The average BMI was 38±3.0 kg/m2. NAFLD was histologically confirmed in 74.9%; the commonest histopathological abnormalities were macrovesicular steatosis (74.9%) and ballooning (40.4%). Simple steatosis occurred in 30.4%, 44.4% presented with NASH, and 31% had severe NAFLD. NASH associated with higher levels of ALT (0.03), ALP (0.02), and glucose (0.02). Cutoff values were, respectively, 23 U/L, 67 U/L, and 81 mg/dL. Their concomitant use provided an 83.1% specificity for NASH. Severe NAFLD associated with diabetes (p=0.02), higher BMI (p=0.01), AST (p=0.04), ALT (p<0.01), ALP (p=0.01), glucose (p=0.02), and ferritin (p<0.01). BMI over 39.3 kg/m2 and ferritin over 178 ng/mL concomitantly provided a 70.5% accuracy for severe NAFLD.

CONCLUSIONS

NASH and severe NAFLD associated with higher levels of ALT, ALP, and glucose. Severe NAFLD associated with higher BMI and higher ferritin levels in this group. The concomitant evaluation of these laboratory tests could help ruling out NASH and safely screening severe NAFLD.

Impact of pre-operative weight loss on non-alcoholic fatty liver disease histopathology and insulin resistance in individuals undergoing bariatric surgery: a propensity matched cross-sectional comparison

BACKGROUND

The effect of weight loss (WL) on histopathological aspects of non-alcoholic fatty liver disease (NAFLD) may provide further insights into the dynamics of hepatic recovery after WL.

OBJECTIVE

To analyze the effects of pre-operative WL on insulin resistance- and NAFLD-related histology in individuals undergoing bariatric surgery (BS) with or without pre-operative WL.

DESIGN AND SETTING

A matched cross-sectional study was conducted at a public university hospital and a private clinic in Campinas, Brazil.

METHODS

An analytical, observational, cross-sectional study was conducted using prospectively collected databases of individuals who underwent BS and liver biopsy at either a public tertiary university hospital (with pre-operative WL) or a private clinic (without pre-operative WL). Random electronic matching by gender, age, and body mass index (BMI) was performed and two paired groups of 24 individuals each were selected.

RESULTS

Of the 48 participants, 75% were female. The mean age was 37.4 ± 9.6. The mean BMI was 38.9 ± 2.6 kg/m2. Fibrosis was the most common histopathological abnormality (91.7%). Glucose was significantly lower in the WL group (92 ± 19.1 versus 111.8 ± 35.4 mg/dL; P = 0.02). Significantly lower frequencies of macrovesicular steatosis (58.3% versus 95.8%; P = 0.004), microvesicular steatosis (12.5% versus 87.5%; P < 0.001), and portal inflammation (50% versus 87.5%; P = 0.011) were observed in the WL group.

CONCLUSION

Pre-operative WL was significantly associated with lower frequencies of macro- and mi- crovesicular steatosis, portal inflammation, and lower glycemia, indicating an association between the recent trajectory of body weight and histological aspects of NAFLD.

Microvesicular Steatosis in Individuals with Obesity: a Histological Marker of Non-alcoholic Fatty Liver Disease Severity

BACKGROUND

In non-alcoholic fatty liver disease (NAFLD), steatosis can manifest through two distinct forms: macrovesicular (macroS) and microvesicular (microS).

OBJECTIVE

To investigate the prevalence of microS and its association with biochemical parameters and NAFLD-related histological findings in individuals with obesity.

METHODS

This is an observational retrospective cross-sectional study, enrolling individuals who underwent bariatric surgery and liver biopsy at a university hospital. A 1:2 propensity matching was performed to pair microS with isolated macroS; this matching enrolled variables "age," "gender," "body mass index (BMI)," and "obesity-associated medical problems." Clinical, biochemical, and histopathological aspects were then analyzed and compared.

RESULTS

Of 115 participants, 88.7% were female; average age was 40.5 ± 5 years and mean BMI was 37.9 ± 3.3 kg/m². Steatosis occurred in 82.6% (67.8% isolated macroS and 14.8% microS). MicroS is significantly associated with higher levels of alanine aminotransferase (ALT) (39.8 ± 26.4 vs. 26.7 ± 17.5; p = 0.04) and glucose (103.8 ± 52.6 vs. 83.3 ± 10.8; p = 0.03) and higher frequencies of moderate to severe macroS (41.2% vs. 2.0%; p < 0.001), portal fibrosis (100% vs. 50%; p < 0.001), perisinusoidal fibrosis (100% vs. 55.9%; p < 0.001), lobular inflammation (100% vs. 41.1%; p < 0.001), and portal inflammation (100% vs. 41.1%; p < 0.001). An independently positive association was observed between intensities of microS and macroS (p < 0.001).

CONCLUSION

MicroS is significantly associated with higher levels of ALT and glucose and higher frequencies of moderate to severe macroS, hepatocellular ballooning, portal fibrosis, perisinusoidal fibrosis, lobular inflammation, and portal inflammation. These findings indicate that microS could be considered a reliable histological marker of NAFLD severity.