Abstract
This study aims to investigate the potential impact of nonalcoholic fatty liver disease (NAFLD) on the risk or severity of community-acquired pneumonia (CAP) in children and adolescents aged 6 to 17 years. Non-contrast chest computed tomography (CT) scans and laboratory data from patients aged 6 to 17 years with respiratory symptoms or fever between July and December 2023 were retrospectively analyzed. NAFLD and its severity were diagnosed based on a liver-spleen CT value ratio. The incidence and distribution of NAFLD across each age group were calculated. Abdominal circumference was measured using CT with specialized software. Chest CT scores quantified the severity of CAP, while inflammatory indices assessed positive C-reactive protein levels and white blood cell counts. Patients with NAFLD were assigned to the observation group, with non-NAFLD patients matched by age and sex served as the control group in a 1:1 ratio. One-way analysis of variance and independent sample rank-sum tests were used to analyze differences in chest CT scores, abdominal circumference, and inflammatory indices. Among 4740 eligible cases, the incidence of NAFLD increased with age, with an overall rate of 5.30%, and was more common in boys. The NAFLD group showed significantly higher abdominal circumference and inflammatory indices than those of the non-NAFLD group (P < .05). There were no significant intergroup differences in chest CT scores or sex (all P > .05). The chest CT score, proportion of males, and abdominal circumference were significantly higher in the moderate-to-severe NAFLD group than that in the mild NAFLD group (all P < .05). No significant intergroup differences were observed in age or inflammatory indices (all P > .05). Patients with moderate-to-severe NAFLD had higher chest CT scores than those with mild NAFLD. Moderate-to-severe NAFLD was associated with an increased risk or severity of CAP in children and adolescents aged 6 to 17 years.
Keywords: acquired pneumonia, alcoholic fatty liver disease, community, computed tomography, non
1. Introduction
The term nonalcoholic fatty liver disease (NAFLD) is also known as metabolic-associated fatty liver disease.[1] This term reflects the pathophysiological processes of adipose tissue metabolism in the liver. Although the exact cause of NAFLD remains unclear, genetic susceptibility and intestinal microecology are thought to contribute to its development. The hepato-intestinal axis, explained by the “multiple hit theory,” is considered a key factor.[2] The diagnosis of pediatric NAFLD is a significant health concern that is increasingly paralleling the childhood obesity epidemic.[3,4] It is now the most common chronic liver disease in children and adolescents. Diagnosis is a positive, yet exclusionary, process. It is primarily suspected in overweight/obese children and adolescents and confirmed by imaging – most commonly ultrasound. Crucially, other liver disease etiologies, such as viral, autoimmune, or metabolic disorders, must be systematically ruled out. While elevated serum alanine aminotransferase levels can suggest liver injury, liver biopsy remains the gold standard for definitively diagnosing nonalcoholic steatohepatitis and staging fibrosis.[5]
NAFLD, often incidentally detected on medical imaging, is more prevalent in adults, with a global incidence of 14 to 32%, most common in the Middle East and least common in Africa.[6,7] Studies employing various research methods have shown significant variations in the prevalence of NAFLD in children, especially before and after the emergence of COVID-19.[8–10]
In 2017, Nseir et al[11] first identified an association between NAFLD and community-acquired pneumonia (CAP) in adults. Subsequent studies have emphasized NAFLD’s role as a contributing factor to pathogenic mechanisms in pulmonary infections and as an independent predictor of mortality in severe CAP cases.[12,13] The risk factors that increase the susceptibility of children and adolescents to pneumonia can be classified into several key areas, including host factors, environmental factors, sources of infection, and prevention.[14] Studies on the impact of NAFLD on lung infections in children and adolescents are limited, leaving its effects on respiratory infections in this age group unclear. Chest computed tomography (CT) scans are widely used to detect lung inflammation, providing visual insights into distribution patterns and severity. The chest CT scoring system for pneumonia, particularly widely used for COVID-19 pneumonia, provides a semi-quantitative assessment of the extent and severity of lung involvement.[15,16] Additionally, chest CT mediastinal window images can provide insights into liver and spleen conditions, although not comprehensive assessments, offering a “window” to observe potential NAFLD in patients.[17–19] Our objective was to assess the impact of NAFLD on children and adolescents aged 6 to 17 years with respiratory symptoms or fever using non-contrast chest CT imaging.
2. Materials and methods
Non-contrast chest CT scans and inflammatory markers, including serum C-reactive protein (CRP) levels and white blood cell (WBC) counts, were retrospectively analyzed in pediatric patients aged 6 to 17 years with respiratory symptoms or fever between July 1, 2023 and December 31, 2023. Patient information was acquired through Picture Archiving and Communication System or Hospital Information System during the case collection and screening phase, and was anonymized prior to subsequent analysis.
2.1. Inclusion criteria
Upper respiratory symptoms or fever within the past week, such as cough, runny nose, or pharyngeal discomfort; Non-contrast chest CT imaging; and WBC counts and serum CRP levels.
2.2. Exclusion criteria
Fever caused by non-respiratory diseases; noninfectious lesions evident on non-contrast chest CT, such as tumors, excluding tuberculosis; Follow-up chest CT scan; Interval between WBC count, serum CRP level, and non-contrast chest CT examination > 2 days; Antibiotic intervention before treatment; Inherited or congenital disorders leading to pulmonary diseases.
NAFLD was assessed by quantifying liver and spleen densities on mediastinal window images from non-contrast chest CT scans. The densities were expressed as CT values (HU). NAFLD was diagnosed when the liver-to-spleen density ratio (RL-S) was ≤ 1.0. Mild, moderate, and severe NAFLD were defined by RL-S values ranging from 0.8 to 1.0, 0.5 to 0.8, and ≤0.5, respectively.[17–19] Patients with NAFLD were assigned to the observation group, with non-NAFLD patients matched by age and sex served as the control group in a 1:1 ratio. Abdominal circumference was measured using ImageJ software (Version 1.53c) (http://imagej.nih.gov/ij) on the aforementioned images, with appropriate window width settings. The magic wand tool obtained abdominal circumference values in millimeters (mm) (Fig. 1).
Figure 1.
(A) Examples of evaluating NAFLD and abdominal circumference using CT images. Two circular regions of interest (ROIs) of approximately 150 mm2 were placed on the CT images of the liver and spleen. The ratio of the mean CT values was calculated as [(0 + (−15) HU)/2]/ [(46 + 47) HU/2] = −0.16, classifying the case as severe nonalcoholic fatty liver disease (NAFLD). (B) Examples of evaluating NAFLD and abdominal circumference using CT images. The abdominal circumference was measured as 949 mm using ImageJ software. CT = computed tomography.
The scoring criteria for the inflammatory indices are as follows:
WBC counts exceeding the normal reference level (one point), otherwise zero points.
Serum CRP levels exceeding the normal reference level (one point) or zero points. The inflammatory index scores ranged from 0 to 2.
The chest CT score was calculated using lung window images from non-contrast chest CT scans. Based on previous research,[15,16] a score of 4 points was assigned when pulmonary exudation or solid shadows occupied 3/4 or more of each lung lobe, while a score of 3 points was assigned for involvement greater than or equal to 1/2 but <3/4 of each lung lobe. A score of 2 points was assigned for involvement greater than or equal to 1/4 but <1/2, and 1 point for involvement <1/4. Absence of pneumonia resulted in a score of zero. The final chest CT score, with 5 lobes, ranged from 0 to 20.
Statistical analyses were conducted using IBM SPSS Statistics (version 19.0; Chicago). The Kolmogorov–Smirnov test assessed normality, with data expressed as mean ± SD for normal distribution or median (Q25, Q75) for non-normal distribution. One-way analysis of variance and independent sample rank-sum tests were used to analyze differences in chest CT scores, abdominal circumference, and inflammatory indices between the 2 groups and among the observed subgroups. Statistical significance was set at P < .05.
This study was approved by the authors’ affiliated institutions (approval no. KZXYLL001 and KZYYJH2025-017-02), and informed consent was waived due to the retrospective design of the study.
3. Results
3.1. Overall situation
From July to December 2023, 6421 children and adolescents aged 6 to 17 years underwent non-contrast chest CT examinations, of whom 4740 met the inclusion criteria for this study. A total of 668 patients were further analyzed. A patient flowchart is presented in Figure 2.
Figure 2.
Process of the patients’ enrollment. *, The non-NAFLD group matched by age and sex served as the NAFLD group in a 1:1 ratio. NAFLD = nonalcoholic fatty liver disease.
The incidence of NAFLD varied across age groups, ranging from 0.61% at 6 years to 7.01% at 17 years, with an overall mean incidence of approximately 5.30%. Notably, the incidence rate increased with age in both sexes; however, boys aged ≥ 10 years exhibited higher rates than girls, except those aged ≥ 16 years (Fig. 3).
Figure 3.
Overview of the NAFLD in ages 6–17 yr. NAFLD = nonalcoholic fatty liver disease.
3.2. NAFLD and non-NAFLD groups
The abdominal circumference was significantly higher in the NAFLD group than in the non-NAFLD group [910.00 (817.00, 1007.00) vs 776.50 (709.75, 844.00), P < .001]. The inflammatory index was also significantly higher in the NAFLD group [1 (1, 2) vs 1 (0, 1), P < .001], indicating significant differences between the 2 groups. No significant difference was observed in the chest CT scores between the 2 groups [1 (0, 2) vs 1 (0, 2), P = .152]. Similar findings were observed in the male and female subgroups within the NAFLD group, with no significant sex differences (P > .05). Detailed results are provided in Tables 1–5.
Table 1.
Comparison of the infection index, chest CT score, and abdominal circumference between the NAFLD group and the non-NAFLD group.
| Type | Non-NAFLD group (n = 334) | NAFLD group (n = 334) | Z | P | |
|---|---|---|---|---|---|
| Infection index | Total | 1 (0, 1) | 1 (1, 2) | −7.156 | <.001 |
| 6–9 yr (n = 60) | 0 (0, 1) | 1 (1, 2) | −3.827 | <.001 | |
| 10–13 yr (n = 97) | 1 (0, 1) | 1 (0, 2) | −2.758 | .006 | |
| 14–17 yr (n = 177) | 1 (0, 1) | 1 (1, 2) | −5.468 | <.001 | |
| Chest CT score | Total | 1 (0, 2) | 1 (0, 2) | −1.431 | .152 |
| 6–9 yr (n = 60) | 2 (1, 4) | 2 (1, 3) | −0.807 | .420 | |
| 10–13 yr (n = 97) | 2 (0, 3) | 1 (0, 2) | −2.337 | .019 | |
| 14–17 yr (n = 177) | 0 (0, 1) | 0 (0, 1) | −0.243 | .808 | |
| Abdominal circumference (mm) | Total | 776.50 (709.75, 844.00) | 910.00 (817.00, 1007.00) | −12.99 | <.001 |
| 6–9 yr (n = 60) | 660.50 (612.25, 709.50) | 796.50 (737.25, 854.75) | −6.616 | <.001 | |
| 10–13 yr (n = 97) | 749.00 (702.50, 806.00) | 881.00 (827.50, 931.50) | −8.732 | <.001 | |
| 14–17 yr (n = 177) | 823.00 (769.50, 890.00) | 984.00 (899.00, 1056.00) | −10.672 | <.001 | |
CT = computed tomography, NAFLD = nonalcoholic fatty liver disease.
Table 5.
Summary of ROC curve analysis for abdominal circumference and NAFLD.
| Age groups | cutoff values (mm) | Sensitivity | Specificity | Youden J | AUC | P | |
|---|---|---|---|---|---|---|---|
| 6–9 yr | Total (n = 120) | 708 | 85.00% | 75.00% | 0.600 | 0.850 | <.001 |
| Male (n = 82) | 726 | 87.80% | 78.05% | 0.659 | 0.894 | <.001 | |
| Female (n = 38) | 708 | 73.70% | 78.90% | 0.526 | 0.760 | .002 | |
| 10–13 yr | Total (n = 194) | 831 | 74.20% | 86.60% | 0.608 | 0.863 | <.001 |
| Male (n = 160) | 831 | 78.70% | 86.20% | 0.651 | 0.873 | <.001 | |
| Female (n = 34) | 743 | 94.10% | 70.60% | 0.647 | 0.855 | <.001 | |
| 14–17 yr | Total (n = 354) | 941 | 63.80% | 93.80% | 0.576 | 0.828 | <.001 |
| Male (n = 266) | 947 | 72.93% | 93.23% | 0.662 | 0.852 | <.001 | |
| Female (n = 88) | 867 | 68.20% | 84.10% | 0.523 | 0.792 | <.001 | |
AUC = area under curve, CT = computed tomography, NAFLD = nonalcoholic fatty liver disease, ROC = receiver operating characteristic.
Table 2.
Comparison of the infection index, chest CT score, and abdominal circumference between male patients in the NAFLD group and the non-NAFLD group.
| Type | Non-NAFLD group (n = 254) | NAFLD group (n = 254) | Z/t | P | |
|---|---|---|---|---|---|
| Infection index | Total | 1 (0, 1) | 1 (1, 2) | −6.45 | <.001 |
| 6–9 yr (n = 41) | 0 (0, 1) | 1 (0, 2) | −2.546 | .011 | |
| 10–13 yr (n = 80) | 1 (0, 1) | 1 (0, 2) | −2.437 | .015 | |
| 14–17 yr (n = 133) | 1 (0, 1) | 1 (1, 2) | −5.539 | <.001 | |
| Chest CT score | Total | 1 (0, 2) | 1 (0, 2) | −1.618 | .106 |
| 6–9 yr (n = 41) | 2 (1, 4) | 2 (1, 3) | −0.809 | .418 | |
| 10–13 yr (n = 80) | 2 (0.25, 3) | 1 (0, 2) | −2.63 | .009 | |
| 14–17 yr (n = 133) | 0 (0, 1) | 0 (0, 1) | −0.197 | .844 | |
| Abdominal circumference (mm) | Total | 789.00 (729.50, 858.00) | 929.00 (841.50, 1018.25) | −12.048 | <.001 |
| 6–9 yr (n = 41) | 665.00 (613.50, 722.50) | 799.00 (753.50, 865.00) | −6.149 | <.001 | |
| 10–13 yr (n = 80) | 761.49 ± 78.82 | 890.24 ± 81.47 | −10.159 | <.001 | |
| 14–17 yr (n = 133) | 832.00 (782.00, 904.00) | 1007.00 (921.50, 1076.00) | −9.918 | <.001 | |
CT = computed tomography, NAFLD = nonalcoholic fatty liver disease.
Table 3.
Comparison of the infection index, chest CT score, and abdominal circumference between female patients in the NAFLD and the non-NAFLD groups.
| Type | Non-NAFLD group (n = 80) | NAFLD group (n = 80) | Z/t | P | |
|---|---|---|---|---|---|
| Infection index | Total | 1 (0, 1) | 1 (1, 2) | −3.129 | .002 |
| 6–9 yr (n = 19) | 1 (0, 1) | 1 (1, 2) | −3.059 | .002 | |
| 10–13 yr (n = 17) | 0 (0, 1) | 1 (0, 1.5) | −1.305 | .192 | |
| 14–17 yr (n = 44) | 1 (0, 1) | 1 (0.25, 2) | −1.388 | .165 | |
| Chest CT score | Total | 1 (0, 3) | 1 (0, 2) | −0.058 | .954 |
| 6–9 yr (n = 19) | 3 (0, 4) | 3 (0, 3) | −0.387 | .699 | |
| 10–13 yr (n = 17) | 1 (0, 3.5) | 1 (0, 3) | −0.036 | .971 | |
| 14–17 yr (n = 44) | 0 (0, 1.75) | 0 (0, 1) | −0.112 | .911 | |
| Abdominal circumference (mm) | Total | 747.18 ± 91.12 | 854.85 ± 125.95 | −5.617 | <.001 |
| 6–9 yr (n = 19) | 640.00 (611.00, 708.00) | 765.00 (683.00, 804.00) | −2.745 | .006 | |
| 10–13 yr (n = 17) | 735.00 (681.50, 794.50) | 834.00 (771.50, 870.50) | −3.531 | <.001 | |
| 14–17 yr (n = 44) | 789.36 ± 79.43 | 906.48 ± 116.27 | −5.517 | <.001 | |
CT = computed tomography, NAFLD = nonalcoholic fatty liver disease.
Table 4.
Comparison of the infection index, chest CT score, and abdominal circumference between sexes in the NAFLD and the non-NAFLD groups.
| Infection index | Chest CT score | Abdominal circumference (mm) | ||||
|---|---|---|---|---|---|---|
| Non-NAFLD | NALFD | Non-NAFLD | NALFD | Non-NAFLD | NALFD | |
| Female (n = 160) | 1 (0, 1) | 1 (1, 2) | 1 (0, 3) | 1 (0, 2) | 791.00 (716.50, 876.00) | 854.85 ± 125.95 |
| Male (n = 508) | 1 (0, 1) | 1 (1, 2) | 1 (0, 2) | 1 (0, 2) | 847.00 (768.25, 945.75) | 933.24 ± 123.73 |
| Z/t | −0.72 | −0.324 | −0.577 | −0.423 | −5.147 | 4.921 |
| P | .472 | .746 | .564 | .672 | <.001 | <.001 |
CT = computed tomography, NAFLD = nonalcoholic fatty liver disease.
3.3. NAFLD group subgroups
Further analysis of patients with NAFLD revealed a significantly higher proportion of males in the moderate-to-severe NAFLD group than in the mild NAFLD group (P = .002). Chest CT score and abdominal circumference were significantly higher in the moderate-to-severe NAFLD group than in the mild NAFLD group (all P < .05). The 2 groups had no significant differences in age or inflammatory indices (all P > .05). Further details are provided in Table 6.
Table 6.
Comparison of parameters pertaining to mild and moderate-to-severe NAFLD.
| Type | Mild NAFLD (n = 249) | Moderate-to-severe NAFLD (n = 85) | χ2/t/Z | P |
|---|---|---|---|---|
| Sex (female/male) | 70/179 | 10/75 | 9.297 | .002 |
| Age (yr) | 12.98 ± 3.16 | 13.12 ± 3.18 | −0.336 | .737 |
| Infection index | 1 (1, 2) | 1 (1, 2) | −0.281 | .779 |
| Chest CT score | 1 (0, 2) | 1 (0, 2) | −2.179 | .029 |
| Abdominal circumference (mm) | 891.63 ± 122.60 | 981.38 ± 122.58 | −5.828 | <.001 |
CT = computed tomography, NAFLD = nonalcoholic fatty liver disease.
4. Discussion
The NAFLD is commonly identified on non-contrast chest CT scans obtained for the evaluation of pneumonia in children and adolescent patients. The global prevalence of NAFLD in children and adolescents has significantly increased in recent years, primarily due to changes in lifestyle patterns during the COVID-19 pandemic.[8,9] Few studies have explored the association between NAFLD and respiratory symptoms or fever in children and adolescents, particularly its potential correlation with CAP in this age group. Although pneumonia of different etiologies presents with distinct chest CT features, such as lobar pneumonia often associated with bacterial infection, the interstitial patterns are typically seen in viral pneumonia. The design of this study precludes the definitive differentiation of causative factors, with the sampling data suggesting that these factors are often multifactorial or interrelated. However, this does not diminish the importance of stratifying pathogenic factors. In contrast, further research on etiological stratification will help deepen our understanding of the relationship between NAFLD and CAP.
This study found the overall incidence of NAFLD among children and adolescents aged 6 to 17 years with respiratory symptoms or fever to be 5.30%, similar to the 5% reported by Nobili et al[20] but lower than the 13% incidence of NAFLD in the general population reported in a meta-analysis.[9] This may be attributed to the study’s relatively young population, and the impact of different imaging methods on examination results should not be overlooked.[21] Conversely, this suggests that NAFLD may not be as severe in children and adolescents in the authors’ region. Contrary to the findings of Anderson et al,[22] which showed a different trend, the incidence of NAFLD gradually increased with age in our study. The incidence of NAFLD was higher in boys than in girls, with a statistically significant difference observed after the age of 10 years, consistent with the results of a sex-divided NAFLD prevalence study by Lee et al.[9]
Abdominal circumference measurement is the simplest method for assessing abdominal obesity[23] and can be easily performed. The size and quantity of adipocytes in obese children increase at approximately 6 years of age, associated with elevated serum CRP levels.[24] Our findings show that abdominal circumference in children and adolescents with NAFLD was higher than that in the non-NAFLD group across all sexes and age groups, providing a set of cutoff reference values for NAFLD at different ages. The positive correlation between abdominal obesity and NAFLD[8] is widely accepted, and our study supports this hypothesis. Given the intricate association between abdominal obesity, abdominal circumference, and NAFLD, it is reasonable to postulate that an elevated abdominal circumference is indicative of more severe abdominal obesity, and that such obesity exacerbates pulmonary inflammation. This suggests that NAFLD may not act as an independent contributor to the development of CAP. In this study, the average abdominal circumference among patients was 92.9 cm, consistent with the results of Song et al.[8] However, there was a significant difference in abdominal circumference between children and adolescents without NAFLD. Our study yielded an abdominal circumference of 78.9 cm, compared to Song et al’s[8] result of 68.1 cm. This discrepancy may be due to lifestyle changes during the COVID-19 pandemic, such as excessive caloric intake, reduced physical activity, or differences in measurement methods. This study performed non-contrast chest CT scans after deep inspiration while holding their breath, which may have caused increased measurement.
Chronic low-grade inflammation is closely associated with NAFLD,[6] although the underlying mechanism remains unclear. Serum CRP, a nonspecific inflammatory marker produced in response to pathogenic microorganisms, has high sensitivity in detecting metabolic disorders, cardiovascular diseases, and hypertension.[25] It can also serve as a diagnostic marker for NAFLD.[26] WBC count is an essential biomarker for managing children with respiratory symptoms or fever; however, it is less effective than CRP and procalcitonin.[5] In this study, the inflammatory index of the NAFLD group was significantly higher than that of the non-NAFLD group, confirming the strong association between NAFLD and inflammation. There was no significant difference in the inflammatory index between the mild and moderate-to-severe NAFLD groups, likely due to the inclusion of individuals with respiratory or fever symptoms, which introduced a background of chronic low-grade inflammation that is inherent to NAFLD.
In the wake of the COVID-19 pandemic, the world, including the authors’ region, has witnessed numerous surges of respiratory infections. Limited research suggests that children with NAFLD have higher rates of COVID-19 infection than those without NAFLD.[27] The “second strike” hypothesis indicates that excessive lipid accumulation in liver cells leads to cytotoxic events, triggering inflammatory responses.[28] Meanwhile, the multiple strike theory expands our understanding of the interaction between the liver axis, inflammation, and intestinal microbes,[29] deepening our knowledge of NAFLD. Studies have revealed a complex bidirectional relationship between NAFLD and COVID-19.[27] While research on CAP and NAFLD in children is limited, studies in adults have shown that NAFLD independently predicts patient prognosis.[6,30] In this study, we assessed NAFLD severity and found that the chest CT score was significantly higher in the moderate-to-severe NAFLD group than in the mild NAFLD group. Our study found that NAFLD was positively correlated with the severity of CAP in children and adolescents, similar to the correlation observed in adults.[30] Given the physiological differences between children, adolescents, and adults, further investigation is needed into the complex bidirectional relationship[27] and the interaction between NAFLD and pulmonary infection in pediatric populations.
This study had some limitations. First, the diagnostic criteria for NAFLD were based on the ratio of CT values between the liver and spleen, which may differ slightly from the gold standard liver biopsy. Meanwhile, the assessment of liver and spleen CT images was limited, as only the mid and upper segments were included. This may compromise the accuracy and reliability of quantitative fat evaluation – particularly in the setting of heterogeneous intrahepatic fat distribution, and most notably among patients with mild NAFLD. Second, the study cohort of patients who underwent non-contrast chest CT consisted of those with more severe clinical symptoms or with radiographic findings inconsistent with their symptomatology, which may have introduced selection bias. Third, although we used a random ratio to establish a negative control group for NAFLD, potential case selection bias may still exist. Finally, the risk factors that increase the susceptibility to pneumonia in children and adolescents are not stratified. Subsequent stratified studies are needed to clarify the relationship between NAFLD and CAP in children and adolescents.
5. Conclusions
In summary, the prevalence of NAFLD in children and adolescents with respiratory symptoms or fever is relatively low but increases with age. Notably, boys aged ≥ 10 years show a consistently higher NAFLD incidence than girls. Abdominal circumference was a significant factor across all age groups and NAFLD severities. While the exact role of NAFLD in CAP remains unclear, patients with moderate-to-severe NAFLD tend to have higher chest CT scores. These findings indicate a potential role for NAFLD in the pathogenesis of CAP in children and adolescents. Therefore, early detection and effective management of NAFLD should be prioritized to optimize the health and well-being of children and adolescents.
Acknowledgments
We would like to thank Wenjie Yang (MD, from ruijin Hospital, shanghai jiaotong university school of medicine, China) for her help in thoughtful suggestions with this paper. We also thank Editage (www.editage.cn) for English language editing.
Author contributions
Conceptualization: Juntao Cao, Guang Yang.
Data curation: Hanwen Shi, Ruilin Gu.
Formal analysis: Juntao Cao, Hanwen Shi, Ruilin Gu, Huijuan Tu, Guang Yang.
Funding acquisition: Huijuan Tu.
Investigation: Hanwen Shi.
Methodology: Ruilin Gu.
Project administration: Juntao Cao, Huijuan Tu, Jianchun Tu.
Resources: Guang Yang.
Software: Juntao Cao.
Supervision: Jianchun Tu, Guang Yang.
Visualization: Jianchun Tu.
Writing – original draft: Hanwen Shi, Ruilin Gu.
Writing – review & editing: Juntao Cao, Guang Yang.
Abbreviations:
- CAP
- community-acquired pneumonia
- CRP
- C-reactive protein
- CT
- computed tomography
- NAFLD
- nonalcoholic fatty liver disease
- WBC
- white blood cell
This work was supported by Suzhou Applied Basic Research Technology Innovation Project (No. SYWD2024076). The funding source has no role in the collection, analysis, or interpretation of the data or in the decision to submit the manuscript for publication.
The authors have no conflicts of interest to disclose.
The datasets generated during and/or analyzed during the current study are not publicly available, but are available from the corresponding author on reasonable request.
How to cite this article: Shi H, Gu R, Tu H, Tu J, Yang G, Cao J. Impact of nonalcoholic fatty liver disease severity on community-acquired pneumonia in children and adolescents aged 6 to 17 years: A retrospective CT-based study. Medicine 2026;105:16(e48414).
HS and RG contributed to this article equally.
Contributor Information
Hanwen Shi, Email: 3144670785@qq.com.
Ruilin Gu, Email: 297392906@qq.com.
Huijuan Tu, Email: jianchun_tu@126.com.
Jianchun Tu, Email: jianchun_tu@126.com.
Guang Yang, Email: xyyg1987@163.com.
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