1. Introduction {#sec0005}
===============

While bariatric surgery is widely accepted as the treatment of morbid obesity, effectively lowering body weight and resolving obesity-related comorbidities, the choice of bariatric technique is still debatable, as many factors must be taken into account. Compared to the gold standard Roux-en-Y gastric bypass (RYGB), laparoscopic mini-gastric bypass (MGB) is a relatively new and popular method in some centers, owing to its easier technique, shorter learning curve and operative times, impressive weight loss (WL), and lower complications [@bib0005].

This technique incorporates a long gastric tube created from the incisura angularis to the angle of His over a 36-F bougie and an antecolic loop gastroenterostomy approximately 200 cm distal to the ligament of Treitz, causing malabsorption and consequently WL. More than 200 cases have been performed in our center with successful results; however, WL is sometimes achieved at the price of malnutrition and its related problems. Its effect on liver function, moreover, has not specifically been studied yet, including its possible effect on non-alcoholic fatty liver disease (NAFLD).

We hereby present a case of morbidly obese patient undergoing MGB, who showed biopsy-proven progression of NAFLD nearly nine months after surgery. This work has been reported in line with the SCARE criteria [@bib0010].

2. Presentation of case {#sec0010}
=======================

A 57 year-old middle-eastern nonalcoholic morbid obese female presented to our bariatric center with an initial body mass index (BMI) of 42.8 kg/m^2^ (weight = 118 kg, height = 166 cm) and obesity related health problems including hypertension (under treatment by metoprolol and captopril) and diabetes mellitus (diagnosed 6 months previously and under control at the time of presentation by lifestyle modifications). She was taking 50 mcg levothyroxine pills daily for hypothyroidism and was euthyroid. She had been selected as part of the Tehran Obesity Treatment Study (TOTS), which enrolls and follows up morbidly obese patients requiring surgical intervention [@bib0015].

Her preoperative evaluations revealed grade-I fatty liver with increased liver echogenicity and span in ultrasonography. Other evaluations including cardiac, pulmonary, and blood biochemistries were insignificant. Viral markers were also negative for hepatitis viruses. Moreover, no other cause for liver disease was identified. She underwent MGB without any incidents, and wedge and needle liver biopsies were performed at the time of the operation ([Table 1](#tbl0005){ref-type="table"}). The biopsy was assessed by a specialized liver pathologist using hematoxylin & eosin, Masson's trichrome, and Iron staining, and was scored according to the NAFLD activity score (NAS) criteria [@bib0020], which is the sum of steatosis grade (0--3), hepatocyte ballooning grade (0--2), and lobular inflammation grade (0--3) in microscopic assessment ([Table 1](#tbl0005){ref-type="table"}). Result showed a score of 2 from a possible maximum of 8. Steatosis was seen in 5--33% of the specimen and inflammation in \<2 foci/200x, with no signs of ballooning. Moreover, there were no features of fibrosis ([Fig. 1](#fig0005){ref-type="fig"}A).Fig. 1(A) Photomicrograph at primary bariatric surgery, showing ballooning (arrow) and steatosis (arrowhead). (B) Photomicrograph at revisional surgery, showing more prominent ballooning (arrows), steatosis (arrowhead), and neutrophilic satellitosis (circles).Fig. 1Table 1Liver biopsy reports at the time of primary and revisional surgeries (at 9 months) and NAFLD activity score (NAS).Table 1Biopsy detailsMGBRevisional surgery (9 months)ItemExtentSCORESteatosisGrade[a](#tblfn0005){ref-type="table-fn"}^,^[b](#tblfn0010){ref-type="table-fn"}*\<5%*05--33%1✓\>33--66%2✓\>66%3LocationZone 30✓✓Zone 11Azonal2Panacinar3Microvesicular steatosis[b](#tblfn0010){ref-type="table-fn"}Not present0✓Present1✓  InflammationLobular inflammation[a](#tblfn0005){ref-type="table-fn"}^,^[b](#tblfn0010){ref-type="table-fn"}No foci0\<2 foci/200x1✓2--4 foci/200x2\>4 foci/200x3✓Microgranulomas[b](#tblfn0010){ref-type="table-fn"}Absent0✓Present1✓Large lipogranulomasAbsent0✓✓Present1Portal inflammation[c](#tblfn0015){ref-type="table-fn"}None to minimal0✓More than minimal1✓  Liver cell InjuryBallooning[a](#tblfn0005){ref-type="table-fn"}^,^[b](#tblfn0010){ref-type="table-fn"}None0✓Few balloon cells1Many cells/prominent ballooning2✓Acidophil bodiesNone to rare0✓✓Many1Pigmented macrophages[c](#tblfn0015){ref-type="table-fn"}None to rare0✓Many1✓MegamitochondriaNone to rare0✓✓Many1  Other findingsMallory's hyalineNone to rare0✓✓Many1Glycogenated nuclei[b](#tblfn0010){ref-type="table-fn"}None to rare0✓Many1✓Iron depositionAbsent0✓✓Present1  Fibrosis stageNone0✓✓Perisinusoidal or periportal1Mild, zone 3, perisinusoidal1AModerate, zone 3, perisinusoidal1BPortal/periportal1CPerisinusoidal and portal/periportal2Bridging fibrosis3Cirrhosis4Total score27[^1][^2][^3]

She was under routine postoperative follow-up at 1, 3, 6, and 12 months, and received supplementation for vitamins and minerals (Pharmaton^®^, Boehringer Ingelheim Inc., Ingelheim am Rhein, Germany), as well as ursodiol, regularly. She was also following her post-operative protocol of at least 70--100 g/day of protein intake without any difficulties. Her blood indices and WL results are provided in [Table 2](#tbl0010){ref-type="table"}.Table 2Patient's preoperative and postoperative weight indices and blood values.Table 2VariableNormal valuesPreoperativePostoperative3 months8 monthsRevisional surgeryWeight, kg55--69118967170BMI, kg/m^2^20--2542.835.125.725.4EWL%----44.895.997.9FBS, mg/dL70--100110829066HbA1c, %\<5.75.55----ALT, U/L7--5531283864AST, U/L8--48282633104ALP, U/L45--1151671678268Total bilirubin, mg/dL0.4--1.511.11.51.2TSH, U/mL0.39--6.162.5--3.6--Total Protein, g/dL6.3--7.9----5.25.2Albumin, g/dL3.5--55.2--2.53.3Calcium, mg/dL8.5--10.210.1--8.18.5Magnesium, mg/dL1.6--2.92--2.11.9Zinc, mcg/dL70--110101--89135Copper, mg/dL80--155119--131--Vitamin B12, pg/mL211--946175----1196Vitamin D3, ng/mL\>3066.7----70Plasma Iron, mcg/dL39--14988--91--WBC, 10^3^/mcL4--106.153.85.215.71RBC, 10^6^/mcL4.2--5.44.1--3.893.02Hemoglobin, g/dL12--15.5141111.28.8Hematocrit, %35--4542.433.833.827.1MCV, fL77--98----86.989.7Platelet, 10^3^/McL150--450262219314278[^4]

At postoperative month eight, she presented with edema, vague abdominal pain, nausea, and vomiting and was admitted. She had lost significant weight during this period, approximating her ideal body weight (BMI = 25.7 kg/m^2^, excess weight loss = 95.9%). Her blood workup revealed mild anemia, mildly elevated liver enzymes, as well as moderate to severe hypoalbuminemia (2.5 g/dL). Hepatitis markers were rechecked and confirmed negative. A liver ultrasound study revealed grade-II fatty liver. Upper endoscopic assessment was insignificant and showed the small stomach pouch with mild erythema at gastro-jejunal anastomosis site. Other evaluations failed to find an etiology for her liver dysfunction. She received total parenteral nutrition and intensive intravenous protein, lipid, and nutrient supplementation. Her condition had not improved one week later, with rising liver enzymes, at which time revisional surgery was decided. A gastrogastrostomy was performed successfully, and another liver biopsy done concurrently, demonstrating a NAS of 7/8 ([Table 1](#tbl0005){ref-type="table"}). Steatosis was seen in 33--66% of the specimen with \>4 foci/200× of inflammation and prominent ballooning. No features of fibrosis were present ([Fig. 1](#fig0005){ref-type="fig"}B).

She began to recover afterwards, and her liver function normalized. She was discharged from the hospital after one week in good health.

3. Discussion {#sec0015}
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NAFLD is an extremely prevalent counterpart of morbid obesity, in up to 90% of this population, and ranges from mild fatty liver changes and steatosis to non-alcoholic steatohepatitis (NASH), with the possibility of progression to liver fibrosis with longstanding disease [@bib0025]. Bariatric surgery in general has shown impressive results on resolution of this condition, in up to 85% of the patients [@bib0030]. However, evidence regarding the effect of various bariatric techniques on NAFLD is incomprehensive, and nearly nonexistent regarding MGB. This report provides a probably unprecedented effect of MGB on liver function, proven by histology.

This overall beneficial effect of bariatric surgery has been shown in different parameters of the liver function, including histologic features of NAFLD, asparate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, and gamma glutamyl transferase [@bib0030], [@bib0035]. This improvement has been shown to be similar in the few available studies between malabsorptive (RYGB) and restrictive techniques (sleeve gastrectomy) [@bib0040], [@bib0045], with the exception of adjustable gastric banding, which demonstrated lower improvement rates [@bib0050]. This can probably be explained by the lower WL achieved by this procedure.

The association between improvement of NAFLD and the magnitude of WL has been consistently observed in the literature [@bib0030]. However, it is suggested that NAFLD improvement could be through non-weight dependent mechanisms as well [@bib0055], and a link was also observed between significant improvement of NAS and ALT normalization much sooner than significant WL goals have been achieved [@bib0060]. On the other hand, three case reports have been published for deteriorating liver function after bariatric surgery despite successful weight loss results, one after bilio-intestinal bypass surgery [@bib0065], another after biliopancreatic diversion surgery [@bib0070], and the third was a patient of ours after MGB. The present case, however, is surprising because it shows severe deterioration of liver histology from NAS 2--7, as early as nine months after surgery.

Although there is no convincing explanation for this presentation, rapid WL is a common feature; our patient achieved her ideal body weight in as early as 9 months. There may also be a link between the mechanism of weight loss and specific bariatric procedures, as shown in a study of comparison between RYGB and MGB in 50 patients, where MGB patients demonstrated significantly poorer liver function tests at one year, despite better WL results [@bib0075]. In addition, the surgical technique itself is of particular importance and will affect the postoperative course. Similar to what Lee et al. reported in their experience with a tailored bypass limb length according to BMI [@bib0080], we suggest individualizing the MGB surgical technique in each patient by measuring bowel length during the operation and then deciding the length of bypassed limb. This may lead to a more controlled and sustained WL, which can help minimize unfavorable postoperative events.

4. Conclusion {#sec0020}
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This case report serves to highlight the importance of future comprehensive studies comparing the effect of different procedures on liver function, NAFLD, and NASH. Their results may consequently affect the choice of bariatric technique for individuals with liver conditions such as NAFLD.

Conflict of interest {#sec0025}
====================

None.

Funding {#sec0030}
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This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Ethical approval {#sec0035}
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This study has been approved by the Human Research Review Committee of the Endocrine Research Center, Shahid Beheshti University of Medical Sciences, No. 2ECRIES 93/03/13.

Consent {#sec0040}
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Informed consent was obtained from the individual included in the study. Ethical approval for this study was obtained from the Human Research Review Committee of the Endocrine Research Center, Shahid Beheshti University of Medical Sciences (No. 2ECRIES 93/03/13).

Author contribution {#sec0045}
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MAKM -- data collection and interpretation, writing the paper, critical revision of the manuscript.

MB -- study design, data collection and interpretation, critical revision of the manuscript.

NR --data collection, final approval of the manuscript.

AK -- IFSO-certified surgeon, data collection, final approval of the manuscript.

Guarantor {#sec0050}
=========

Maryam Barzin, MD, PhD.

[^1]: Components of liver biopsy used in NAS calculation.

[^2]: Signifying deterioration.

[^3]: Signifying improvement.

[^4]: BMI, body mass index; EWL, excess weight loss; FBS, fasting blood sugar; HbA1c, glycosylated hemoglobin level; ALT, alanine aminotransferase; AST, aspartate aminotransferase; ALP, alkaline phosphatase; TSH, thyroid stimulating hormone; WBC, white blood cells; RBC, red blood cells; MCV, mean corpuscular volume.
