Material and Method: Patients diagnosed with obesity followed at the pediatric gastroenterology outpatient clinic between June 2020 and November 2021 were included in this study. The patients were divided into two groups based on the presence of hepatosteatosis. Neutrophil-to lymphocyte ratio (NLR) and plateletto-lymphocyte ratio (PLR) were compared between the two groups.

Results: There were 34 patients in the group without steatosis and 35 patients in the group with steatosis. Obese patients in the non-steatosis group had a mean body weight of 67.5 kg, mean height of 151.5 cm, mean BMI of 27.8 and a mean BMI SDS of 2.4. Obese patients in the non-steatosis group had a mean body weight of 62 kg, mean height of 150 cm, mean BMI of 27.1 and a mean BMI SDS of 2.3. There was no significant difference between the groups in terms of body weight, height, BMI and BMI SDS values (p>0.05). When the groups were compared, the steatosis group showed higher NLR and PLR compared to non-steatosis group. The NLR values were 0.94 (0.78-1.54) in the non-steatosis group and 1.57 (1.05-2.21) in the steatosis group (p =0.005). The PLR values were 83.9 (67.3-111.7) in the non-steatosis group and 106.6 (93.4-138.2) in the steatosis group (p =0.003).

Conclusion: NLR and PLR can be used as simple, easy and independent markers for the prediction of steatosis in obese patients.

It is known that obesity complications that affect the morbidity and mortality in adults also occur in children and adolescents. Non-alcoholic fatty liver disease (hepatosteatosis), one of the well-recognized complications of obesity, is also the most common liver disease all over the world. Hepatosteatosis is defined as the presence of steatosis in more than 5% of hepatocytes in the absence of significant alcohol intake, medication use or a genetic disease⁴. Non-alcoholic steatohepatitis (NASH) develops in one-quarter of individuals with hepatosteatosis and subsequent progression to liver cirrhosis occurs in one-fourth of them.

The complete blood count (CBC) is an easy and inexpensive test that includes leukocyte, neutrophil, lymphocyte and platelet counts, all of which are used as inflammatory markers. Neutrophilto-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are inexpensive and widely available hemogram parame-ters. While the neutrophil-to-lymphocyte ratio is used as a predictor of systemic and local inflammation, the platelet-to-lymphocyte ratio serves to predict inflammation and platelet aggregation. Elevations of these two ratios are considered as a predictor of poor prognosis. Both parameters are also used to predict prognosis in rheumatic diseases, COPD, pulmonary thromboem-bolism and concomitant community-acquired pneumonia as well as for the prediction of cardiovascular and renal complications in diabetic patients^5-9. Hepatosteatosis affects one-half of obese children. Therefore, it would be useful to diagnose hepatosteatosis in obese children as early as possible. While ultrasonography is widely used for the diagnosis of hepatosteatosis, it could be more readily detected by a routine complete blood count. The aim of this study was to investigate the utility of NLR and PLR in predicting steatosis, a severe complication of obesity, in obese pediatric patients.

Hemoglobin, neutrophil, lymphocyte and leukocyte counts were obtained from the CBC reports. For hemogram analysis, an adequate amount of venous whole blood samples was drawn into vacuum K2-EDTA blood collection tubes with a purple cap after 8-12 hours of fasting. The blood tubes were then inverted 8-10 times and tested on an automated analyzer (Cell-Dyn Ruby Analyzer; Abbott, Abbott Park, IL) within 6 hours of collection. Neutrophil-to-lymphocyte ratio and plateletto- lymphocyte ratio were calculated. NLR was calculated by dividing neutrophil count by lymphocyte count, and PLR by dividing neutrophil count by platelet count. Age, sex and anthropometric measurements of the patients were noted.

Patients with an active infectious disease, diabetes mellitus, systemic hypertension, hyperlipidemia, chronic disease, syndromic obesity or hypothyroidism and smokers were excluded from the study.

Steatosis was classified into three grades according to abdominal ultrasound findings: Grade 1, only mild diffuse increase in the echogenicity of the liver; Grade 2, moderate increase in the echogenicity of the liver with slightly impaired visualization of intrahepatic vessels; Grade 3, marked increase in the echogenicity of the liver with poor or no visualization of intrahepatic vascular structures and posterior segment of the right lobe of the liver. Patients were divided into two groups based on the presence of hepatosteatosis. Approval was obtained from the local ethics committee prior to initiation of the study.

Statistical Analysis
Statistical analysis was conducted to evaluate two groups according the presence of hepatosteatosis in obese patients. Kolmogorov-Smirnov test was used to check whether numerical laboratory and demographic data followed a normal distribution. Independent samples t-test or Mann–Whitney U test was used for comparison of two groups as appropriate. All statistical analyses were performed using IBM SPSS for Windows, version 23.0 (IBM Corp.; Armonk, NY) soft-ware package, and the level of significance was set at 0.05.

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Table 1: Demographic characteristics of obese patients with or without hepatosteatosis.

Laboratory workup of the patients showed significantly higher neutrophil and leukocyte counts and lower lymphocyte count in the group with hepatosteatosis (Table 2).

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Table 2: Laboratory results of obese patients with or without hepa-tosteatosis.

Consistently, NLR and PLR were significantly higher in the group with hepatosteatosis. Median (interquartile ranges) NLR values were 0.94 (0.78-1.54) in patients without steatosis and 1.57 (1.05-2.21) in patients with steatosis (p =0.005). Median (interquartile ranges) PLR values were 83.9 (67.3-111.7) in patients without steatosis and 106.6 (93.4-138.2) in in patients with steatosis (p =0.003) (Figure 1).

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Figure 1: Box plots of neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in obese patients with or without hepatosteatosis.

Increased prevalence of obesity is associated with increased prevalence of obesity-related disorders. Many health issues are associated with obesity, including cardiovascular disease, hypertension, type 2 diabetes and hepatosteatosis¹⁴. The liver is an important site for the synthesis of acute phase proteins. Monokines IL-1, IL-6 and TNF-α, which are synthesized and released by stimulated monocytes are considered as me-diators of acute phase proteins in the liver¹⁵. Inflammatory cytokines are secreted by the adipose tissue and cause liver disease. After being synthesized in a local lesion at the initial stage of inflammation, IL-6 moves to the liver via bloodstream, leading to a rapid induction of several acute phase proteins (16). Hepatosteatosis is a well-known complication of obesity and the most common liver disease across the globe. Hepatosteatosis is defined as steatosis affecting more than 5% of the liver weight in the absence of excessive alcohol intake, medication use or a genetic disorder⁴. Hepatosteatosis is of significance because 25% of affected patients develop steatohepatitis and 25% of them develop liver cirrhosis. While the incidence of fatty liver disease ranges from 10 to 77% in obese children, 38% of children with fatty liver disease are obese. In line with previous reports, hepatosteatosis was identified in 50.7% of the obese patients in the current study. Hepatosteatosis is infrequent in children under 8 years of age, and the mean age at presentation is 12 years¹⁷. Consistently, the mean age of the patients with hepatosteatosis was 136 months in our study. Children with hepatosteatosis are mostly obese and asymptomatic. Hepatosteatosis has gained significance worldwide due to its common occurrence in the general population and its progression to liver cirrhosis and liver failure. With an alarmingly increasing prevalence across the globe, obesity is a major nutritional problem that affects 25-30% of children^18,19.

In obesity, leptin and other chemokines are involved in the transmigration of bone marrow-derived monocytes into fat tissue, resulting in increases in IL-6, TNF-α and many other cytokines. In turn, this leads to an elevation of acute phase proteins such as CRP. All of these events explain the chronic low-grade inflammation that actively contributes to changes in hematologic parameters ². In obese individuals, inflammatory cells infiltrate into adipose tissue and inflammatory cells and adipocytes induce chronic systemic inflammation by producing cytokines^20,21. Neutrophils, lymphocytes and platelets are major components of blood that are involved in inflammatory process ²². In recent years, it has been shown that NLR and PLR are mark-ers of systemic inflammation and may be correlated with prognosis in a number of cardiovascular diseases, malignancies and chronic inflammatory conditions. Both NLR and PLR can be easily measured and have emerged as practical markers that can provide valuable information for the diagnosis and prognosis of various diseases. Increased neutrophil count and elevated NLR have been demonstrated in obese patients in a study by Atmaca et al.²³. In a study by Aydın et al. involving obese adolescents, greater NLR was found in obese patients with hepatosteatosis than in healthy controls²⁴. In a study by Furuncuoğlu et al.²⁵ in 223 obese patients aged 18 to 65 years, higher white blood cell and neutrophil counts were detected in obese individuals versus control group. Similarly, neutrophil count and NLR were found to be higher in obese patients with hepatosteatosis compared to patients without hepatosteatosis and the difference between the two groups was significant. Platelets interact with endothelial cells, leukocytes and progenitor cells, thereby triggering migration of inflammatory cells into the site of injury and release of inflammatory cytokines in abundance and eventually, creating an inflammatory environment in the lesion area. İn inflammatory events, the platelet count increases and lymphocyte count decreases, resulting in an increase in the platelet/lymphocyte ratio²⁶. NLR and PLR can be easily obtained through peripheral blood count to identify inflammation. Both NLR and PLR measurements cost less and are more valuable compared to some other markers including IL-6, IL-8 and TNF-alpha. In this study, obese patients with steatosis showed higher neutrophil and platelet counts and lower lymphocyte count compared to obese patients without steatosis.

A number of limitations should be noted for this study. First, this was a single-center study with a limited sample size. Secondly, due to the retrospective design of the study, we cannot exclude the possibility that potential preanalytical errors in routine evaluation of hemogram analysis may have been overlooked. Nevertheless, preanalytical process for hemogram analysis is thoroughly followed at our center.

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